User Manual
Thymatron® System IV

Somatics LLC
720 Commerce Drive, Suite 101
Venice, Florida 34292
Technical Support
USA and Canada(800) 642 – 6761 or +1-847-234-6761
Fax: (847) 234 – 6763
E-mail: sales@thymatron.com

UM-TS4, Rev. 22

Thymatron® System IV Instructions for Use
User's Manual for Thymatron® System IV
Prescription use only – Federal law restricts this device to sale by or on theorder of a physician.
CAUTION

Electroconvulsive Therapy (ECT) is a complex medical procedure. Its proper and safe conduct requires astaff of licensed healthcare professionals who are trained and have experienced in-person supervision
with the associated procedures, have received clinical privileges for ECT from the appropriate hospitalcommittee, and have carefully read and are thoroughly familiar with the medical literature concerning
the risks, benefits, complications, and methods of ECT. Specifically, practitioners intending to use theThymatron System IV should be familiar with ECT-related concerns including medical conditions that
affect risks, adverse effects, pre-ECT evaluation, medications used during ECT, ECT procedures andtechniques, physiological phenomena, consent, ECT unit staffing, evaluation of outcome, and postcourse ECT management. Practitioners should keep current with information about these concerns
published in major textbooks, in major journals of psychiatry, and by professional psychiatricorganizations. They should also be familiar with the FDA final order of December 26, 2018 (83 FR
66103-66124). Clinicians who administer ECT should participate in continuing education about ECT.
It is essential that doctors planning to use the Thymatron® System IV device read and follow thewarnings and recommendations of the Task Force Report of the American Psychiatric Association as set
forth in “The Practice of Electroconvulsive Therapy” (APA, 2001), which states, in part, that "A small
minority of patients treated with ECT later report devastating cognitive consequences. Patients may
indicate that they have dense amnesia extending far back into the past for events of personal significanceor that broad aspects of cognitive function are so impaired that the patients are no longer able to engage
in former occupations...in some patient self-reports of profound ECT-induced deficits may reflect
objective loss of function...In rare cases, ECT may result in a dense and persistent retrograde amnesia
extending to years..."
It is essential to read all of the information in the Safety Information section of this manual, pages 6–10.
Copyright© 1999; 2000; 2001; 2002; 2003; 2004; 2005; 2006; 2009; 2013; 2015; 2016; 2018; 2019; 2024
Somatics LLC. All rights reserved. No portion of this manual may be reproduced by any means without thepermission of Somatics LLC.

Technical
SupportUSA and
Canada(800) 642 – 6761 or +1-847-234-6761
Fax: (847) 234 – 6763
E-mail: sales@thymatron.com

1Thymatron® System IV Instructions for Use
Contents
INTENDED USE ............................................................................................................................................... 6
INTENDED PATIENT POPULATION................................................................................................................. 6
SAFETY INFORMATION .................................................................................................................................. 6
WARNINGS ............................................................................................................................................. 6
PRECAUTIONS........................................................................................................................................ 7
ADVERSE EVENTS .......................................................................................................................................... 9
SERIOUS ADVERSE EVENTS................................................................................................................... 9
OTHER RISKS.......................................................................................................................................... 9
RISKS OF COGNITIVE MEMORY EFFECTS.............................................................................................10
TECHNIQUE OF ECT.......................................................................................................................................11
TO THE TREATING PHYSICIAN......................................................................................................................11
RISK REDUCTION FEATURES ........................................................................................................................11
RISK OF PROLONGED SEIZURES AND CARDIAC ARRHYTHMIAS ........................................................11
RISK OF THYMATRON® COMPONENT FAILURE ..................................................................................12
EFFICACY AND SAFETY OF THE THYMATRON® ECT DEVICE .....................................................................12
EFFICACY OF THE THYMATRON® ECT DEVICE ...................................................................................12
SAFETY OF THE THYMATRON® ECT DEVICE.......................................................................................16
RISK OF BRAIN INJURY .....................................................................................................................16
MEMORY AND COGNITIVE RISKS .....................................................................................................17
REFERENCES .........................................................................................................................................20
DISCLAIMER / WARRANTIES.........................................................................................................................24
SPECIFICATIONS............................................................................................................................................25
EXPLANATION OF SIGNS AND SYMBOLS .....................................................................................................27
INSTALLATION ..............................................................................................................................................28
OPERATING INSTRUCTIONS..........................................................................................................................282

Thymatron® System IV Instructions for Use
POWER ON/OFF......................................................................................................................................28
SELF TEST..............................................................................................................................................28
PERCENT ENERGY DIAL .......................................................................................................................28
LIGHT-EMITTING FUNCTION DISPLAYS ...............................................................................................29
SAFETY MONITOR CIRCUIT ALARM TEST............................................................................................30
FRONT PANEL JACKS ............................................................................................................................30
FLEXDIAL™ OPERATION ......................................................................................................................31
PAPER LOADING INSTRUCTIONS..........................................................................................................33
STIMULUS CABLE CONNECTION ..........................................................................................................33
MONITORING CABLE CONNECTION .....................................................................................................33
LEAD-WIRE CONNECTIONS ..................................................................................................................34
SEIZURE MONITORING CONSIDERATIONS ...........................................................................................34
MONITORING ELECTRODES APPLICATION ..........................................................................................34
CHANNELS 3 & 4 SELECTION ................................................................................................................35
STIMULUS ELECTRODES APPLICATION ...............................................................................................35
IMPEDANCE TEST (FOR STATIC IMPEDANCE) ......................................................................................36
MOUTH PROTECTION............................................................................................................................37
BASELINE EEG COLLECTION ................................................................................................................37
STIMULUS DOSE SELECTION ................................................................................................................38
STIMULUS PROGRAMS: FACTORY PROGRAMMED ..............................................................................39
STIMULUS PROGRAM SELECTION ........................................................................................................39
FREQUENCY SELECTION ......................................................................................................................40
PULSEWIDTH SELECTION .....................................................................................................................40
STIMULUS DOSE FOR BILATERAL, BITEMPORAL, BIFRONTAL, LART ECT .........................................40
STIMULUS DOSE FOR UNILATERAL ECT ..............................................................................................40
STIMULUS TITRATION PROCEDURE .....................................................................................................403

Thymatron® System IV Instructions for Use“BENCHMARK” METHOD FOR SETTING AND ADJUSTING STIMULUS .................................................41
TYPICAL COURSE OF TREATMENT ...............................................................................................................41
TARDIVE SEIZURE.................................................................................................................................42
WORSENING OF PSYCHIATRIC SYMPTOMS..........................................................................................42
MANIC SYMPTOMS ...............................................................................................................................42
TREATMENT STIMULUS ADMINISTRATION .........................................................................................42
SEIZURE MONITORING .........................................................................................................................43
GAIN AND POSITION SETTINGS ............................................................................................................45
TURN OFF PRINTING IN A CHANNEL ....................................................................................................47
CHANGING EEG GAIN RAPIDLY............................................................................................................47
SEIZURE QUALITY MEASURES .............................................................................................................47
BASELINE RETENTION..........................................................................................................................48
TO ENABLE/DISABLE SEIZURE QUALITY MEASURES ..........................................................................48
EEG FREQUENCY MEASURES ...............................................................................................................48
PRINTER PAPER SPEED SELECTION......................................................................................................49
POWER SPECTRAL ANALYSIS (FFT) SELECTION ..................................................................................49
USER SPECIFIED FLEXDIAL™ SELECTIONS .........................................................................................49
TRANSFERRING DATA BETWEEN A PC AND THYMATRON® SYSTEM IV ............................................50
INPUT HOSPITAL NAME FOR THE PRINTED REPORT ........................................................................51
DOWNLOAD PRE-RECORDED TREATMENT DATA FROM PC FOR REPRINTING BY THYMATRON®
SYSTEM IV .........................................................................................................................................51
FLEXDIAL™ DATA IN: DATA IN ........................................................................................................51
UPLOAD TREATMENT DATA AUTOMATICALLY TO A PC.................................................................52
DISPLAY EEG/EMG/ECG ON THE PC SCREEN ....................................................................................52
OUTPUT TREATMENT DATA MANUALLY .........................................................................................53
REPRINT THE LAST TREATMENT ......................................................................................................54
FLEXDIAL™ DATA OUT: REPRINT ....................................................................................................544

Thymatron® System IV Instructions for Use
SET DATE & TIME IN PRINTED REPORT ............................................................................................54
ELECTROMAGNETIC COMPATIBILITY (EMC) ...............................................................................................55
GENERAL NOTES...................................................................................................................................55
LIST OF CABLES AND ACCESSORIES ....................................................................................................55
ELECTROMAGNETIC EMISSIONS ..........................................................................................................56
ELECTROMAGNETIC IMMUNITY ..........................................................................................................57
INDEX ............................................................................................................................................................61
ADDENDUM I (FIRMWARE CHANGES) ..........................................................................................................63
ADDENDUM II (ELECTRODE PLACEMENT) ...................................................................................................64
ADDENDUM III (INSTRUCTIONS TO PATIENT) ..............................................................................................70
ADDENDUM IV (FLEXDIAL FLOW CHART) ...................................................................................................74
ADDENDUM V (MOCA TEST) .........................................................................................................................75
ADDENDUM VI (INSTRUCTIONS FOR LEGACY METAL OLD TYPE STIMULUS ELECTRODES) .....................76
ADDENDUM VII. TABLES OF STIMULUS DETAILS FOR EACH % ENERGY SETTING OF THE DOSE DIAL .....785

Thymatron® System IV Instructions for Use
INTENDED USE
Type of Device:

The Thymatron® System IV is an ECT device

Device usage:

Therapeutic device

Application area:

For use in treating catatonia, severe major depressive episodes (MDE)
associated with major depressive disorders (MDD) or bipolar disorder (BPD) inpatients age 13 years and older who are treatment-resistant or who require a
rapid response due to the severity of their psychiatric or medical condition.
Alternative available treatments that may or may not be as effective as ECT
include various behavioral and pharmacological interventions.

Users:

Medical Doctors, Psychologists, Neurologists

INTENDED PATIENT POPULATIONThis device is intended to be used as part of the ECT treatment procedure with patients of age 13 years andolder, under treatment by a medical doctor, a psychologist or a neurologist, with a condition as described in the
Intended Use. Patients must be capable of giving informed consent or have a legally recognized substitute. For
each ECT session, patients should be assessed to be in sufficiently good medical condition to tolerate theprocedure.
ECT does not reliably treat PTSD, other anxiety disorders, personality disorders, or medical disorders that cause
symptoms of major depression, and the Thymatron System IV is not intended for use in treating such disorders.
Anxiety disorders, PTSD, personality disorders, and medical disorders can underlie major depression or coexist
with it, causing suicidality or other depressive symptoms.

SAFETY INFORMATION
Please read the following important safety requirements before using the Thymatron® System IV ECTInstrument.
WARNINGS
Various medical conditions are associated with substantially increased risk from ECT, including
risk of death. These include unstable or severe cardiovascular conditions (recent myocardial
infarction, unstable angina, poorly-compensated congestive heart failure, severe valvular cardiac
WARNINGdisease), vascular aneurysms susceptible to rupture with increased blood pressure, increased
intracranial pressure, recent cerebral infarction, severe chronic obstructive pulmonary disease,asthma, pneumonia and anesthesia risk level ASA 4 or 5. Pulmonary risks of ECT associated withgeneral anesthesia and neuromuscular blocking agents include hypoxemia, hypoventilation,
aspiration, and upper-airway obstruction.
ECT device use may be associated with disorientation, confusion, and memory problems.
WARNING

6

Thymatron® System IV Instructions for Use

WARNINGWARNINGWARNING

When used as intended this device provides short term relief of symptoms. The long-term safety
and effectiveness of ECT treatment has not been demonstrated, and long-term follow-up may beneeded.
Some patients who were suicidal before receiving ECT eventually committed suicide after
receiving ECT, including after receiving ECT with a Thymatron® device.
Administering ECT to a patient with an implanted DBS device can damage the DBS device or
cause it to malfunction and cause injury to the patient.

PRECAUTIONS
For patients with brain tumor, brain aneurysm, myocardial infarction, coronary insufficiency, heart
failure, or aortic aneurysm medical specialists in Neurology or Cardiology should be consulted todetermine additional precautions needed, if any.
Do not remove the top or bottom covers of the Thymatron® System IV. There are no user
serviceable parts inside. Any servicing must be performed by qualified service personnel.
Do not use any cables or lead wires that appear to be damaged.
The Thymatron® System IV device is defibrillator protected. Nevertheless, for safety reasons, allcable connections between the Thymatron® System IV ECT Instrument and the patient must be
disconnected prior to initiation of the defibrillation stimulus.
Avoid the risk of accidental shock to medical personnel. Do not contact the patient, or any
conductive surface touching the patient, unless wearing electrically insulated gloves. If holding thepatient’s jaw or touching the patient's head during the electrical stimulus, make sure to use
electrically insulating gloves.
Do not subject the Thymatron® System IV device to extreme moisture, and do not use it after it has
been partially or totally immersed in liquid or when a significant amount of liquid has been spilledon it. Power the unit off and have it checked by a qualified technician before powering it on or
using it again.
Only use the Thymatron® System IV device with the Somatics’ Treatment and Monitoring Cables.

The Treatment and Monitoring Cables are not interchangeable and cannot be inserted into thewrong front panel connector. Attempting to force the Treatment Cable into the connector intended
for the Monitoring Cable (and vice versa) will damage both the connector and the cable.
The ECG function of the Thymatron® System IV device is used only to obtain a heart rate to help
assess the efficacy of the seizure; it is not intended to be used to make diagnoses. Do not use theThymatron® System IV ECG function to monitor the patient's heart for any other purpose.

7Thymatron® System IV Instructions for Use
The EMG function of the Thymatron® System IV device is used only to obtain an estimate of the
motor seizure duration to help assess the efficacy of the seizure; it is not intended to be used tomake diagnoses. Do not use the Thymatron® System IV EMG function to monitor the patient's
muscle or nerve activity for any other purpose.
The built-in electroencephalogram (EEG) functions are used only to assist in identifying theefficacy of the induced seizure and its endpoint. Do not use these EEG functions for any otherpurpose. Absence of EEG activity does not prove that seizure activity is absent, because seizure
may occur outside EEG detectability. Seizure can occur while EEG shows nothing.
Do not dispose of your Thymatron® System IV device in the general waste. As per Directive
2002/96/EC for the disposal of electrical and electronic equipment, please contact the manufacturer
for instructions.
Prior to initiating ECT on a patient with a cochlear implant, healthcare professionals should discuss
the issue with an otolaryngologist or audiologist and review the cochlear implant Instructions for
Use.
Thymapad® electrodes are single-use only and must be discarded after the treatment. The
Thymatron® System IV Treatment Cable, Monitoring Cable and lead wires can be cleaned bywiping them off with a Germicidal Disposable Cloth. Steel stimulus electrodes may be cleaned
with soapy water or alcohol. The Thymatron® device has no special requirements for restrictedenvironment during transport or storage, beyond Standard Sub-clause 10.1 criteria.
EEG, EMG and ECG are shown only to assess treatment quality and must not be used formonitoring or diagnosis.

In English speaking countries: Please check annually on the website Thymatron.com for the latest version of
the Thymatron User's Manual.
It is the policy of Somatics LLC, recorded in 2018, that the product life of the Thymatron(R) System IV device
is ten years from invoice date, after which it is no longer suitable for clinical use.
In the USA: In the interests of avoiding litigation we provide here our warning that Scientology and its affiliate
CCHR have threatened to sue ECT device makers and psychiatrists in the USA who do not deliver a warningthat ECT can cause brain damage, regardless of any evidence about it. 7/3/24.

8

Thymatron® System IV Instructions for Use
ADVERSE EVENTS
As with any therapy, ECT has risks. Certain patients will experience adverse events in conjunction withelectroconvulsive therapy. Patients should be made aware of these risks and confirm that they fully understandthem prior to consenting to therapy.
Per FDA requirements, the treating doctor should include in the written Informed Consent form of each ECT
patient a statement of the potential adverse effects from ECT as described in this manual.
The most common reported adverse effects of ECT are: Headache. Muscle soreness. Mild to moderate
pain/discomfort, including jaw pain. Nausea. Disorientation immediately after seizure induction. Memory
dysfunction (see further discussion below).

SERIOUS ADVERSE EVENTS
Recent estimates in the medical literature of the mortality rate associated with ECT are 1 per 10,000 patients or
1 per 80,000 treatments.
Other serious adverse events have occurred, including adverse reaction to anesthetic agents / neuromuscular
blocking agents; adverse skin reactions (e.g., skin burns); cardiac complications, including arrhythmia,
ischemia/infarction (i.e., heart attack), acute hypertension, hypotension, and stroke; cognition and memory
impairment; brain injury; dental/oral trauma; general motor dysfunction; physical trauma (i.e., if inadequate
supportive drug treatment is provided to mitigate unconscious violent movements during convulsions)
including fractures, contusions, injury from falls, dental or oral injury; hypomanic or manic symptoms (e.g.,treatment- emergent mania, postictal delirium or excitement); neurological symptoms (e.g., paresthesia,
dyskinesias); tardive seizures; prolonged seizures; non-convulsive status epilepticus; pulmonary complications(e.g., aspiration/inhalation of foreign material, pneumonia, hypoxia, respiratory obstruction such as
laryngospasm, pulmonary embolism, prolonged apnea); visual disturbance; auditory complications;onset/exacerbation of psychiatric symptoms; partial relief of depression enabling completed suicide;
homicidality; substance abuse; coma; falls; and device malfunction (creating potential risks such as excessive
dose administration), and death.
Certain patients are more likely to experience severe adverse events, including those with pre-existing cardiac
illness, compromised pulmonary status, a history of brain injury, or medical complications after earlier coursesof anesthesia or ECT. Concurrent administration of antipsychotic (neuroleptic) medication may increase therisks of adverse cardiac, pulmonary, and neurological events, and falls. Concurrent administration of stimulants
may increase the risks of cardiac and neurological complications, such as prolonged seizure. All of thisinformation should be assessed in developing the treatment plan for a particular patient.
OTHER RISKS
Completed suicide in ECT patients has a reported rate of 0.5 per 100 patient years, but higher in patients
recently discharged after hospitalization with suicidality. Studies have shown that partial improvement along
the course of ECT, before remission is obtained, can enable suicidal behavior or suicide in patients previously

9Thymatron® System IV Instructions for Use
too ill to plan or commit suicide. Likewise, suicide is a concern after ECT treatment; for instance, one study
found that ECT patients had a slightly higher suicide rate within seven days after their last ECT treatment thannon-ECT inpatients (Munk-Olsen et al., 2007). A meta-analysis found that 30% of patients with treatmentresistant depression attempt suicide, with a rate for completed suicide of 0.47 per 100 patient years which
included similar incidence following DBS, VNS and ECT (Bergfeld et al., 2018).
ECT may result in worsening of an underlying medical condition either by: (1) ineffective treatment or (2) thetreatment itself, particularly when it exacerbates the symptoms.

RISKS OF COGNITIVE MEMORY EFFECTS
Cognitive side effects are experienced in varying types and severity by ECT patients. ECT treatment may be
associated with disorientation, confusion and memory problems, including short-term (anterograde) and longterm (retrograde or autobiographical) memory loss following treatment. These side effects tend to go away
within a few days to a few months after the last treatment with ECT. However, incomplete recovery is
possible. In rare cases, patients may experience permanent memory loss or other deficiency in cognition orfunction.
FDA regulations require that each patient receiving ECT have his cognitive status monitored prior to
beginning ECT and throughout the course of treatment via a formal neuropsychological assessment which
includes evaluation of specific cognitive functions (e.g., orientation, attention, memory, executive function).
Neuropsychology consultation should help select tests for individual patients. One tool that may be helpful inmonitoring along the course is the MoCA (Moirand et al, 2018). Maximum MoCA score is 30, normal is 26 orhigher. Add one point if patient is not educated past high school. See Addendum V and:https://www.parkinsons.va.gov/resources/MOCA-Test-English.pdf. Additional tests may be desirable, such as
for autobiographical memory.
Studies have shown that the methods used in ECT administration have a significant impact on the nature andmagnitude of cognitive deficits. In general, the American Psychiatric Association recognizes that thefollowing treatment parameters are each independently associated with more pronounced cognitive side
effects:• Bilateral electrode placement;• Sine wave stimulation;• High electrical dosage relative to seizure threshold;• Closely spaced treatments;• Larger numbers of treatments;• Concomitant psychotropic medications;• High dosage of barbiturate anesthetic agents.

10Thymatron® System IV Instructions for Use
TECHNIQUE OF ECTUsers of ECT devices should carefully follow the specific ECT treatment techniques and procedures outlined in
Chapters 6-11 of the American Psychiatric Association’s “The Practice of Electroconvulsive Therapy:
Recommendations for Treatment, Training and Privileging – A Task Force Report” (2001).
ECT requires general anesthesia with neuromuscular blocking agents and supported ventilation. These should
be administered by a qualified anesthetic specialist.
Requisite pre-ECT medical and psychiatric assessments in every patient include pertinent medical andpsychiatric history, complete physical examination, ECT anesthesia assessment, dental assessment, and anyother clinically appropriate studies as determined by the treating psychiatrist.
Prior to ECT, the patient should ingest nothing by mouth for at least eight hours. At the start of the ECTprocedure, monitoring and stimulus electrodes are attached. Then general anesthesia is given with aneuromuscular blocking agent and hyperventilation with oxygen. When the muscles are fully relaxed, a mouth
protector is inserted and the electrical stimulus then applied.
During the treatment, EMG, ECG and EEG are monitored for occurrence of generalized seizure and until the
seizure terminates. ECG usually shows heart rate acceleration at seizure onset and deceleration at seizure end.
Typical minimum motor seizure is 20 sec. If the seizure lasts less than 20 sec., consider repeating the stimulus at
an appropriately higher dose. EEG shows brain electrical activity. Endpoints can differ among these because
they reflect different locations in the brain. If seizure continues beyond about 100 seconds, consider termination
by infusing intravenous propofol, midazolam, methohexital or similar short-acting agent. Ventilation iscontinued until spontaneous respiration returns. After ECT, the patient is observed for an hour or longer, withvital sign, lung auscultation, and cognitive function checks.

TO THE TREATING PHYSICIANThe U.S. Food and Drug Administration (FDA) requires that patients receive in writing and understandthe statements listed in Addendum III before receiving ECT. You may duplicate and disseminate these"Instructions to Patients" without limitation. Delivery of this required information about ECT should be
witnessed and documented in medical records.

RISK REDUCTION FEATURESRISK OF PROLONGED SEIZURES AND CARDIAC ARRHYTHMIASThe two most frequent complications during an ECT treatment session are excessively long seizures andirregular heart rhythms (Nuttall et al, 2004), both of which can be detected by routine monitoring during thetreatment. The Thymatron®’s integral brain-wave monitor (electroencephalogram, EEG) enhances the safety of
ECT by allowing the treating doctor to detect signs of a prolonged seizure so it can be terminated withintravenous medication. However, a brain seizure can occur or continue without accompanying EEG activity.
Likewise, a heart monitor (electrocardiogram, ECG) allows the treating doctor to detect irregular heartbeat
patterns as they occur so that they can be managed with intravenous medication. The Somatics Thymatron®

11Thymatron® System IV Instructions for Use
monitors start recording automatically as soon as the ECT stimulus is delivered and continue until they areturned off by the doctor.
In addition to the paper EEG record, the Somatics Thymatron® device has an auditory EEG monitor thatallows the user to tell without looking at the paper EEG whether or not EEG signs of seizure have stopped. In
a study of 82 consecutive ECTs using this auditory EEG, physicians determined the occurrence and theduration of the induced EEG seizure with a high degree of accuracy (Swartz and Abrams, 1986).
RISK OF THYMATRON® COMPONENT FAILURE
In the extremely rare event of catastrophic failure of an ECT device component, there is a remote possibility ofdelivering an electrical stimulus dose in excess of that set by the operator, potentially causing excessive
memory disturbance. To prevent such an occurrence, the Somatics Thymatron® device includes an
independent separate redundant safety circuit that automatically measures the electrical charge of the output
each time the stimulus button is pressed and prevents delivery of any stimulus charge exceeding by more than
5% that set by the operator. To test the integrity of the electrical connection to the patient, the Somatics
Thymatron® device includes a static impedance test initiated by a button press. The test current is too small to
be felt. This test helps assure good electrode contact and prevent excessive heat release onto the skin.

EFFICACY AND SAFETY OF THE THYMATRON® ECT DEVICE
The below review of the clinical research literature on electroconvulsive therapy (ECT) focuses on the risks andbenefits of the most widely-used Thymatron® ECT device models: the DG, DGx, and System IV. 1 This review
emphasizes controlled studies with random assignment, blind ratings and statistical validation; older
impressionistic reports without validated observations are not included. For each of the three topics (i.e.,
Efficacy of the Thymatron® ECT Device, Risks of Brain Injury, and Memory and Cognitive Risks) the most
pertinent study on the topic is summarized first, followed by brief summaries of other studies that are germaneto the topic.
Several old reports not involving a Thymatron® ECT device stated concern about potential adverse effects of
ECT on brain function, but the technique of ECT and electronic design of the devices used for this treatment
have since advanced to mitigate those concerns. An old study claiming brain injury in cats receiving electricallyinduced convulsions (Alpers and Hughes, 1942) failed to use muscle-relaxant drugs before stimulation or propercomparison animals. Breggin (1979) emphasized cerebral petechial hemorrhages (small blood spots on thebrain), but when animals were restrained from banging their heads no petechiae occurred (Siekert et al, 1950).
A prospective study in patients receiving modern ECT that employed blindly-analyzed serial magnetic
resonance images obtained before, 2-3 days after ECT, and 6 months later did not support the existence of brain
injury (Coffey et al, 1991).
EFFICACY OF THE THYMATRON® ECT DEVICE
Petrides et al (2001), in a National Institutes of Mental Health (NIMH)-supported 4-hospital collaborative study,
1 The DG, DGx and Thymatron System IV deliver the same electricity. The Thymatron IV differs from previous models in monitoringand in ways that the doctor can select the electrical stimulus. Somatics no longer sells the DG or DGx

12Thymatron® System IV Instructions for Use
used a Thymatron® DGx device to prospectively treat 253 patients with nonpsychotic (n=176) and psychotic(n=77) unipolar major depression with bilateral ECT at 50% above titrated threshold. Included were patients
aged 18 to 85 years with primary major depression, unipolar type, with or without psychosis, and a baseline
Hamilton Depression scale score >20. Excluded were those with a lifetime diagnosis of bipolar illness,schizophrenia, or schizoaffective disorder, a medical contraindication to ECT, a systemic or neurologicalcondition that might affect mood, failure to respond to a trial of ECT or a lithium-tricyclic antidepressantcombination during the present episode, and substance dependence during the past year. Of the total sample,
56% were female and mean age was 56 years.
A standard ECT protocol was administered with bilateral electrode placement, seizure threshold determination,
dosing at 50% above the titrated seizure threshold, and monitoring seizure efficacy by the duration of EEG-and
EMG-monitored seizures. Patients were rated with the 24-item Hamilton depression scale and aneuropsycholical test battery 24-72 hours before the first ECT and after each subsequent ECT before thefollowing treatment. Remission was defined as 2 consecutive post-ECT-treatment Hamilton Depression Rating
Scale scores <11, and a decrease of at least 60% on this scale from baseline on this scale. Chi-squared analyses
were used to evaluate the relationship between unadjusted remission status and psychosis status. Multivariate
logistic regression analyses were used to evaluate the relationship between remission status and psychosis
status, adjusted for the effects of confounding or moderator variables; such analysis compared the longitudinal
profile of total Hamilton scale scores measured 24-72 hours after each ECT for the psychotic and nonpsychotic
depression groups. Most patients achieved scores of ≤10 and >60% reduction in scores for the first 8 ECTs
administered, meeting the criteria for remission. For 217 completers of the acute treatment course, the overallremission rate was 87%, with a 95% remission rate for psychotic depression and 83% for non-psychotic
depression patients. Side effects among study dropouts included confusion, memory loss, headache, andnausea.
Earlier, the efficacy of ECT had been supported by several controlled trials against antidepressant medications
and by several double-blind, random assignment comparisons of genuine versus sham ECT. Some of thesestudies are summarized below.
ECT versus AntidepressantsGreenblatt, Grosser, and Wechsler (1964) included for study all severely depressed patients admitted to 3
state hospitals in Boston. All patients were randomly assigned to receive a course of 9 ECTs (n=28), or
imipramine 200-250 mg/day (n=73). At the end of the one-year study period (after which systematic
treatment assignment was discontinued), 76% of the ECT sample was rated markedly improved by acentral team of Massachusetts Mental Health Center physicians, compared with 37% of the imipramine
sample (p<.01 by chi-square).
Shepherd M et al. (1965) conducted a collaborative double-blind trial designed by the Clinical Psychiatry
Committee of the British Medical Research Council, in which patients with endogenous depression wererandomly assigned to receive a minimum of 4 weeks of treatment with ECT (n=58), the tricyclic
antidepressant imipramine (n=58), or placebo (n=58). On completion of 4 weeks of treatment physicians’
blind global outcome assessments showed 84% of the ECT group to be improved, compared with 72% of
those on imipramine; 71% of the ECT group showed no or only slight depressive symptoms, comparedwith 52% of the imipramine group (chi-squared = 8.75, p<0.0005).
Genuine ECT vs. Sham ECT
Brandon et al. (1984) randomly assigned 95 major depressives to courses of either genuine (n=53) or sham(n=42) bilateral ECT. Eighteen patients failed to complete a full course of treatment, leaving 77 who

13Thymatron® System IV Instructions for Use
completed the trial. Treatment was administered twice per week with a maximum of 8 ECT treatments. On
the blindly-administered Hamilton depressive rating scale, the improvement in the group given realtreatment was significantly greater than that in the group given simulated (sham) treatment both at 2 weeks(p=0.014) and at 4 weeks (p=0.0001). At follow-up at 12 and 28 weeks, there was no difference between
the treatment groups. At the end of the 4-week trial consultants who were blind to the allocation oftreatment rated the patients who had received real treatment as having made a significantly greater
improvement than the patients who had received simulated treatment (p<0.0005).
In the Nottingham study, Gregory et al. (1985) randomly assigned 60 depressives to genuine unilateral ECT(n=19), genuine bilateral ECT (n=21) or sham ECT (n=20) to be administered twice weekly, withapproximately 8 ECTs in total per patient. Results on the blindly-administered Hamilton Depression Rating
Scale showed improvements of 31 points in the unilateral ECT group, 28 points in the bilateral ECT group,and 14 points in the sham ECT group. However, longer-term follow-up did not identify such differences
between the groups.
Abbott et al (2013) reported twelve DSM-IV manic-depressive depressed patients treated with a Thymatron®
System IV, rated on the Hamilton scale before and after a course of ECT. They exhibited a statisticallysignificant mean depression scale improvement of 27.6 points. Nine patients achieved remission; three did not.
Azuma et al (2007) studied 14 treatment-resistant depressives who received bilateral ECT with a Thymatron®
System IV. Statistically significant improvement in Hamilton Depression Scale scores was achieved, with 43%
scoring under 8 points on this scale post-ECT. Postictal suppression measured by the Thymatron® System IV
significantly predicted therapeutic outcome.
Heikman et al (2002) used a Thymatron® DGx ECT device to treat 24 major depressives randomly assigned tohigh-dose right unilateral ECT, moderate-dose right unilateral ECT, or low-dose bifrontal ECT. Blindlyobtained Hamilton Depression scale scores at baseline and after the ECT course showed an overall 66%
improvement, with the highest improvement (73%) recorded for the high-dose right unilateral group. 13 patients
experienced remission from depression and nine did not.
Heikman et al. (2002b) separately reported that depression showed remission to ECT with a Thymatron ® DGx
ECT device in 2 of 24 patients whose depression was of low severity or was accompanied by a somatic or
psychiatric comorbidity. Among patients with higher severity and no comorbidity remission was achieved inten and not in six.
Huang CJ et al (2017) studied 95 inpatients with depression receiving at least 6 ECT sessions with a
Thymatron® device. Quality of life, symptom severity, and functioning were assessed before and after ECT on
the Hamilton Depression scale and the Modified Work and Social Adjustment Scale CT. All measures showedstatistically significant improvements after treatment without notable adverse effects. After ECT, HAMD
scores averaged 6.6 (normal) and ranged from 1 to 34 (severe depression).
Kellner, et al (2005) used a Thymatron® DGx to administer ECT to 131 highly suicidal unipolar major
depressives, out of 455 unipolar depressives admitted to hospital for ECT. Suicidal intent was scored atbaseline and before each ECT session with item 3 on the 24-item Hamilton Depression Rating Scale. Suicide
ratings of these 131 patients ultimately dropped to zero, including for the 13 patients who had actuallyattempted suicide. Of the 355 patients who received ECT during the study, 304 achieved remission – defined14

Thymatron® System IV Instructions for Use
as two consecutive Hamilton depression scale ratings ≤10 and a ≥60% reduction in Hamilton depression scale
total score – and 51 did not. Two males, aged 76 and 80, suicided during the study.
Lin CH et al (2013) studied 55 treatment-resistant major depressives (44 unipolar, 11 bipolar) who received
ECT with a Thymatron® System IV. Treatment-resistant depression was defined as a failure to respond toaggressive interventions of three or more kinds of antidepressants with adequate dosages and durations. The
severity of depression was measured using the 17-item Hamilton Rating Scale for Depression (HAMD-17) andthe Clinical Global Impression-Severity (CGI-S) administered by trained psychiatrists before ECT, after every
3 sessions of ECT, and at the end of ECT. The intraclass correlation coefficient of between-rater reliability was
0.95. Scores on both scales showed statistically significant reductions in depression severity after the end of
ECT: The HAMD-17 fell from 30.8 to 7.3 (p<0.001) and the CGI-S fell from 6.3 to 2.8 (p<0.001).
Lin CH et al. (2018) compared responses to depression in patients treated with ECT using a Thymatron®
System IV and patients treated with fluoxetine. ECT produced response in 96 of 104 patients (92%) and not 8
patients, versus a response in 66 of 112 patients (59%) and not in 46 with fluoxetine. ECT patients responded
faster and more frequently experienced headache.
Prudic et al. (2004) performed a study using undisclosed ECT devices including sine wave devices, in whichclinical remission from depression was obtained in 30.3% to 46.7% at hospitals in the New York City
community. Relapse after initial remission was more frequent in patients with a comorbid personality disorder.
The authors hypothesized but did not establish a cause of the low efficacy.
Ranjkesh et al (2005) randomly assigned 39 DSM-IV patients with major depression to receive courses of 8
bifrontal, bitemporal, or right unilateral ECT with a Thymatron® DGx ECT device. Blindly-obtained
Hamilton Depression scale ratings at baseline and after the 8th ECT revealed 73% improvement overall.
In Sackeim et al. (1993), a study that did not did not use a Thymatron device, 59% of patients who responded
to ECT relapsed within twelve months.
Tran et al (2017) presented the case of a 25-year-old woman hospitalized for a major depressive episode andsuicidality in the context of bipolar 1 disorder, whose symptoms fully remitted with 1 ECT with a Thymatron®
device.
Williams et al (2008) used a Thymatron® DGx ECT device to administer 1.5 times threshold bitemporal ECT
to 515 patients with DSM-IV unipolar major depression, obtaining a 68% reduction in Hamilton Depression
scale scores after treatment. Remission occurred in 329 patients (64%) and not in 186.
In Winokur, et al. (1990), a study conducted before Thymatron devices were available and when sine wave
ECT devices were common, patients experienced more rehospitalizations after ECT than matched patients
who did not receive ECT. The authors did not establish a cause.

15Thymatron® System IV Instructions for Use
SAFETY OF THE THYMATRON® ECT DEVICERISK OF BRAIN INJURY
Sartorius et al. (2016) conducted a prospective, MRI-based study of whole brain gray matter volume and voxelbased cortical thickness in depressed patients with a mean age of 52 years who received a course of titrated right
unilateral ECT with a Thymatron® System IV device. 20 psychiatric inpatients with a Major Depressive
Episode (mean Hamilton Depression Scale score=31.8, mean Mini-Mental State Examination score=27.9)
entered the study, of whom 18 received pre- and post-ECT MRIs. Statistically significant whole brain graymatter increases were observed in the temporal lobe regions of interest, including hippocampus, amygdala, andhabenula, as well as an increase of cortical thickness in temporal lobe and insula. The authors concluded thatthe data (1) widely excluded white matter loss as an indirect cause of grey matter growth, and (2) added support
to the hypothesis that ECT enables cerebral plasticity, in contrast to older claims that ECT induces brain
damage. No adverse side effects were reported.
Bai T et al. (2019) studied 61 depressed patients receving ECT with a Thymatron® System IV device comparedwith 23 healthy controls. ECT was found to increase local activity of the dorsomedial prefrontal cortex andenhanced connectivity with the posterior cingulate cortex that was positively correlated with clinicalimprovement. These findings support the functional plasticity of the dorsomedial prefrontal cortex and its
potential reorganization by ECT that may underlie its antidepressant effect. The study reported no signs of
injury.
Bouckaert et al. (2016) obtained structural magnetic resonance images in 88 severely depressed elderly patients
who received courses of ECT with a Thymatron® System IV device. Following ECT, there was a statisticallysignificant improvement in Montgomery-Asberg Depression Rating Scale (MADRS) scores, a statisticallysignificant but short-lived increase in hippocampal volume, and no change in serum levels of brain-derived
neurotrophic factor. The authors concluded that ECT-induced hippocampal growth is a transient phenomenon
possibly related to ECT-induced normalization of physical activity levels. They reported no signs of injury.
Cano et al. (2017) studied 12 patients with treatment-resistant depression who received bilateral ECT with a
Thymatron® System IV device and compared them with 10 healthy controls on high-resolution structural MRI
and hippocampal metabolite concentrations before and after a course of treatment. ECT-induced regional graymatter volume increases in the left medial temporal lobe revealed a statistically significant positive association
with clinical improvement, which was not true for neuroinflammatory changes as measured by hippocampal
metabolites. The authors concluded that structural, but not metabolic, changes in the left medial temporal lobe
are useful neuroimaging biomarkers of ECT-induced clinical improvement in treatment-resistant depression.
Cano et al. (2018) used MRI to assess whole-brain gray matter volume in 24 subjects with treatment-resistantdepression before and after courses of bilateral or right-unilateral ECT given with a Thymatron® System IV
device. Bilateral ECT induced bilateral gray matter volume increases in the limbic system, compared withgray matter volume increases limited to the right hemisphere after right-unilateral ECT, which may reflect theoccurrence of neuronal increase.
Doddi SR et al. (2018) reported a 72 year old man with severe depression following a subarachnoid hemorrhage
demonstrated on CT who received 9 bifrontal ECTs 33 days post-hemorrhage with a Thymatron® System IV

16

Thymatron® System IV Instructions for Use
device, with dramatic improvement in sequential Montgomery-Asberg Depression Scale scores, and MiniMental State Scores that ranged from 28-30, all within the normal range. A repeat CT scan after the first ECT
showed no intracranial hemorrhage or any other acute intracranial process. Five months later he remained in fullremission without signs of injury.
Ende et al. (2000) used proton magnetic resonance spectroscopic imaging to study hippocampal effects of theThymatron® DG ECT device as reflected in N-acetylaspartate signals. In 17 patients receiving either unilateralor bilateral ECT (all of whom improved with treatment), no differences were found from 30 control subjects inhippocampal N-acetylaspartate signals, failing to provide evidence for ECT-induced hippocampal atrophy orcell death.
Gryglewski G et al. (2018) carried out Magnetic Resonance Imaging scans in 14 patients with unipolar
treatment-resistant depression before and after courses of right unilateral ECT administered with a Thymatron®
System IV device. Increases in volume of the right hippocampus, right amygdala, and right putamen by wereobserved, localized in the basal and lateral nuclei, and the corticoamygdaloid transition area of the amygdala,
the hippocampal-amygdaloid transition area and the granule cell layer of the dentate gyrus. Cortical thickness
increased in the temporal, parietal and insular cortices of the right hemisphere. These lateralized ECT-induced
structural changes occurred in hippocampal subfields and amygdala nuclei that have been implicated in thepathophysiology of depression and support the potential for neuroplasticity in adulthood.
Hirano J et al. (2017) used task-related functional near-infrared spectroscopy to compare 108 healthy controls
with 30 patients with major depressive disorder or bipolar depression before and after an ECT seriesadministered with a Thymatron® System IV device. Pre-ECT, patients exhibited statistically significantly
smaller oxyhemoglobin values in the bilateral frontal cortex during a verbal fluency task than healthy controls,values that increased statistically significantly after ECT. A decrease in depression severity was significantly
correlated with an increase in oxyhemoglobin values in the right ventrolateral prefrontal cortex. Impaired
functional responses, observed during the cognitive task in depressed patients, were normalized after ECT,
suggesting that the acute therapeutic effects of ECT may reduce abnormal functional responses to cognitive
tasks in the frontal brain regions of depressives.
Kranaster L et al. (2014) analyzed serum levels of the established brain injury markers protein S-100 andneuron-specific enolase in 19 patients with depression at baseline and throughout courses of ECT administeredwith a Thymatron® System IV ECT device. Protein S-100 and enolase levels remained stable throughout thetreatment course, failing to support the presence of neuronal cell injury markers in patients receiving ECT.
Sartorius et al. (2018) obtained whole brain magnetic resonance imaging scans in 92 major depressives before
and after ECT administered with a Thymatron® System IV device. Stastically significant gray matter volume
increases were observed in the hippocampus and amygdala that did not correlate with psychopathology, age,gender or number of ECT sessions.
MEMORY AND COGNITIVE RISKS
Possible cognitive side effects of ECT include disorientation, orbital-frontal syndrome, forgetting (retrograde
amnesia), learning impairment (anterograde amnesia), and delirium. Possible causes of delirium include tardive
seizure and occult seizure. Cognitive side effects can be affected by treatment method including stimulus dose,17Thymatron® System IV Instructions for Useelectrode placement, stimulus pulse width, anesthesia details, long seizure duration, neurological and medical
conditions, and medications. Case reports suggest that some medications (e.g., lithium) predispose to cognitive
deficits, and others (e.g., memantine, rivastigmine) may decrease them (Alizadeh et al., 2015; van Schaik et al.
2015).
Nuninga et al. (2018) compared 48 depressed patients and 19 healthy controls to investigate the effects ofbilateral ECT on cognition in depression in a longitudinal case-controlled study. Included were patients aged
>18 years with a diagnosis of unipolar or bipolar depression and an indication for ECT. Excluded were thosewith past or present medical condition or brain pathology, prior ECT within 6 months, or present
pregnancy/lactation. Patients underwent various cognitive tests – including of working memory, verbal
fluency, visuospatial abilities, verbal/visual memory and learning, processing speed, inhibition, attention andtask-switching, and premorbid IQ – at baseline (n = 43), after ten bitemporal ECT sessions with a Thymatron®
System IV (n = 39), and six months after the tenth ECT session (n = 25). Healthy controls underwent the same
cognitive assessment at baseline and after five-weeks. Clinical response was defined as a 50% reduction in
Hamilon depression scale score compared to baseline. The overall effects of ECT on cognition were assessed
via a multivariate repeated measures mixed model; a univariate mixed model was used to investigate theeffects of ECT separately on each cognitive variable. Within the patient group, transient adverse cognitive side
effects were observed for verbal memory and learning, and verbal fluency. None of the cognitive domains
tested showed persisting impairments after six months. Autobiographical memory was not assessed. The
authors concluded that the data show that although bilateral ECT has short-term negative cognitive effects that
could be explained by a decrease in cognitive performance, a lack of learning effects, or a combination of both,these negative effects on cognition appear to recede 6 months post-ECT.
Ng et al (2000) used a Thymatron® DGx to treat 32 major depressives with courses of right-unilateral ECT(mean = 9.4). The mean percentage recall of Personal Memory test items recorded at baseline was 68% after
6 ECTs, 72% at treatment endpoint, and 87% one month later. Wechsler Adult Intelligence Scale scores did
not change with ECT.
Obbels J et al. (2018) assessed 110 subjects (mean age 73) with unipolar major depression who were referredfor ECT. Subjects underwent baseline cognitive testing and then received an average of 14 treatments with a
Thymatron® System IV device (right unilateral, 60%; bilateral, 7%; initially unilateral switched to bilateral,33%). The same cognitive testing was repeated 6 months after the last ECT, though 26% of subjects declined
retesting at this follow-up. There were no statistically significant changes from baseline to 6 months post-ECT
in any of the neuropsychological assessments (visual memory, verbal memory, delayed recall, and executivefunction). In examinations of patient-level data, cognition statistically significantly improved in 14% of patientsand significantly declined in 12%.
In a series of 81 elderly depressed patients treated with a Thymatron® System IV device, Mini-Mental State
Examination scores were not below pretreatment levels one week post-ECT, although some patients had
exhibited preexisting brain atrophy (Oudega et al., 2014). In another series of 65 similarly treated elderly
patients, deficits in executive function and processing speed appeared only transiently (Dybedal et al., 2016).
Schat et al (2007) used a Thymatron® DGx ECT device to treat 83 DSM-IV medication-free patients withunipolar depression who had been evaluated at baseline on tests of behavioral (everyday) and semantic
memory. One year after a course of bilateral or unilateral ECT, neither everyday nor semantic memory scores

18Thymatron® System IV Instructions for Use
were reduced from baseline; bilateral ECT was associated with improved semantic memory scores.
Mohn & Rund (2016) evaluated a group of 31 patients with major depressive disorder prior to and 6 weeks
after non-standardized ECT. Statistically significant improvements were found six weeks after ECT inprocessing speed, attention/vigilance, and visual learning, with other cognitive domains unchanged frombaseline.
Smith GE et al (2010) conducted a randomized controlled trial in unipolar major depressives, comparing
multiple memory test effects after 12 and 24 weeks of ECT with the Thymatron® System IV device andpharmacotherapy with a nortriptyline-lithium combination. Twelve-week objective anterograde memory
scores and 24-week subjective memory scores were statistically significantly improved for both treatmentgroups compared with baseline. There were no clinically significant memory outcome differences between
ECT and drug therapy for depression.
van Oostrom et al (2018) studied 19 medication-free treatment-resistant major depressives. They underwent awhole-brain magnetic resonance imaging scan and a neuropsychological examination one week before andwithin 1 week after the course of ECT with a Thymatron® System IV device. With ECT, hippocampal
volumes increased statistically significantly; this increase correlated with a decrease in cognitive functioning.
The authors concluded that their findings tentatively suggested that the temporal increase in hippocampal
volum after treatment, which may result from neurotrophic processes and is thought to be crucial for the antidepressive effect, is also related to the temporary cognitive side effects of ECT. Earlier, Bouckaert et al.
(2016) had reported statistically significant but short-lived ECT-induced increases in hippocampal volume,
concluding that their data suggested that hippocampal volume increase after ECT was a transient phenomenon
possibly related to ECT-induced normalization of physical activity levels. They reported no signs of injury.
Verwijk et al (2014) assessed global cognitive function, memory, and executive functions in 42 depressed
patients before and one week and 6 months after courses of ECT administered with a Thymatron® System IV
device. There was no decline for any of the neurocognitive tests after ECT. Medium to large post-ECT
improvements in neurocognitive functioning one week post-ECT were statistically significant for the MiniMental State Examination, Visual Association Test, 10 Words Verbal Learning Test, and Expanded Mental
Control Test.
Ziegelmayer C et al (2017) examined neurocognitive performance in a sample of 20 treatment-resistant ECTnaive depressed subjects. Cognitive functioning was assessed at baseline, 1 week, and 6 months after 12 to 15
unilateral ECTs with a Thymatron® System IV device. No adverse effects were observed in any of thecognitive domains examined.
Falconer et al (2010) treated 24 patients with severe depression with a course of bilateral ECT administeredwith a Thymatron® DGx device. Patients were assessed before ECT, during ECT, within the week after ECT
and 1 month after ECT with a battery of visual memory tests including spatial and pattern recognition
memory, pattern-location associative learning, and delayed matching. Patients showed significant impairments
in visual and visuospatial memory both during and within the week after ECT. Other deficits resolved within 1month following ECT, but not those in spatial recognition memory. Later testing was not reported.

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Thymatron® System IV Instructions for Use
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Thymatron® System IV Instructions for Use
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Electroconvulsive Therapy Is Related to Increased Hippocampal Volume: Exploring the Role of Brain
Plasticity. J ECT 34:117-123.
Van Schaik AM, Rhebergen D, Henstra MJ, et al. (2015), Cognitive impairment and electroconvulsive therapy
in geriatric depression, what could be the role of rivastigmine? A case series. Clinics and Practice 5:68-72.
Verwijk E, Comijs HC, Kok RM, et al. (2014), Short- and long-term neurocognitive functioning after
electroconvulsive therapy in depressed elderly: a prospective naturalistic study. Int Psychogeriatr. 26:315-24.
Williams MD, Rummans T, Shampson S, et al. (2008), Outcome of ECT by race in the CORE multi-site study.
JECT 24:117-21.
Winokur G, Coryell W, Keller M, Scheftner WA (1990), Relationship of ECT to course in affective illness: a
Collaborative Study. Eur Arch Psychiatry Clin Neurosci. 240(1):54-59.
Ziegelmayer C, Hajak G, Bauer A, et al. (2017), Cognitive Performance Under Electroconvulsive Therapy(ECT) in ECT-Naive Treatment-Resistant Patients With Major Depressive Disorder. J ECT 33:104-110.

23

Thymatron® System IV Instructions for Use

DISCLAIMER / WARRANTIES
Please note that nothing in this manual constitutes, or should be construed as, a claim by Somatics LLC that
confusion, cognitive impairment, or memory loss (short-term, long- term, recent, remote, transient, or
persistent), or structural brain change (brain injury) cannot occur as the result of ECT or the general anesthesia
administered with ECT.
Many patients experience temporary loss of recent or remote memories with ECT, particularly with traditional
bilateral ECT. A few patients have reported experiencing persisting loss of memories or memory functions after
ECT. Mental and physical illnesses, anesthesia, medications, and postponement of treatment each have their own
adverse effects, which can be substantial.

The outcome of ECT treatment depends on many clinical aspects outside the ECT device, including the physical,
psychiatric and emotional condition of the patient prior to and at ECT, details of the ECT treatment other thanthe ECT device settings, including anesthesia and medication exposure. By using the Thymatron® System IV
device, the user accepts responsibility for describing details of those and of pre-existing conditions including
brain injury and atrophy, and cognitive difficulties, and for disclosing all appropriate information about risks of
ECT to patients, their families and their guardians (if any).

Somatics, LLC warrants that reasonable care has been used in the design and manufacture of this medical
device. Handling, storage and preparation of this medical device as well as other factors relating to the patient,diagnosis, treatment, and other matters beyond the control of Somatics, LLC directly affect this medical device
and the results obtained from its use. Further, no representation or warranty is made that a Somatics, LLC
product will not fail or cause temporary or permanent cognitive deficits. Somatics, LLC disclaims responsibility
for any medical complications directly or indirectly resulting from the use of this product.

Except as expressly provided by this limited warranty, SOMATICS, LLC IS NOT RESPONSIBLE FOR ANY
DIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES BASED ON ANY DEFECT, FAILURE OR
MALFUNCTION OF ITS PRODUCTS WHETHER THE CLAIM IS BASED ON WARRANTY,CONTRACT, TORT OR OTHERWISE.
THIS WARRANTY IS IN LIEU OF AND EXCLUDES ALL OTHER WARRANTIES NOT EXPRESSLYSET FORTH HEREIN, AND SOMATICS, LLC MAKES NO WARRANTY—EXPRESS OR IMPLIED—INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OR COMPLIANCE WITH ANY
FEDERAL, STATE OR LOCAL LAW, RULE OR REGULATION. IN ADDITION, SOMATICS, LLC
EXPRESSLY DISCLAIMS TO THE FULLEST EXTENT ALLOWED BY LAW, RULE OR REGULATION
ANY WARRANTY PROVIDED UNDER ANY LAW.

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Thymatron® System IV Instructions for Use
SPECIFICATIONSSTIMULUS OUTPUT
Current: 0.9 amps constant current, limited to 450 volts, isolated from line
current Frequency: 10 to 70 Hz, in 10 Hz increments (to 140 Hz in LOW
0.25/0.3 Programs) Pulsewidth: 0.25 to 1.5 ms, in 0.25 ms increments (0.3
ms is available)
Duration: 0.08 to 8.00 s in increments of equal charge
Maximum output: Standard maximum output across 220 ohms impedance, 504 mC (99.8 joules).
Actual (delivered) treatment output shown on printed report in mC
RECORDING
4 recording channels: channels 1 & 2, EEG; channel 3, EMG; channel 4, ECG.
8 user selectable gain positions for EEG channels (10, 20, 50, 100, 200, 500, 1,000 and 2000 μV/cm) and EMG
or ECG channels (50, 100, 200, 500, 1000, 2000, 5000 and 10,000 μV/cm)
REQUIREMENTS 100-130 volts (120 volts) AC, 60 Hz, single phase. 150 VA. (220-240 volt,
50/60 Hz, switchable)
STIMULUS GENERATION
Waveform: bipolar, brief pulse, square wave
IMPEDANCE
Static Impedance Test: 0 to 3000 ohms static (+/- 100 ohms) at 800 Hz (L.E.D. and printed
report) Dynamic Impedance Measure: 0 - 500 ohms (printed report)
SEIZURE MONITORING
Channel specifications:
Maximum gain: EEG, 10 μV/cm; EMG 50 μV/cm; ECG
50 μV/cm Common mode rejection: 80 dB
Isolation: full, opto-electronic
Printer paper speed: user selectable: 10 - 50 mm/s
Seizure Quality Measures:
Postictal Suppression Index (EEG): range,
0-100% Average Seizure Energy Index(EEG)
Maximum Sustained EEG Power and Time to Peak EEG Power
Maximum Sustained EEG Coherence and Time to Peak EEG
Coherence Duke University EEG Measures
Power Spectral Analysis by Fast Fourier
Transform, (FFT) Peak Heart Rate: beats/min
Computer Seizure Endpoint Estimates by EEG and EMG

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Thymatron® System IV Instructions for Use
EEG Frequency Measures:
95% Spectral Edge
Frequency MedianFrequency
Relative Delta PowerDIMENSIONS
Weight: 22 lb.
Height: 5.5”
Width: 17.5”
Depth: 13.0”
The Thymatron® System IV Treatment Cable, Monitoring Cable and lead wires can be cleaned bywiping them off with a Germicidal Disposable Cloth. Steel stimulus electrodes may be cleaned withsoapy water or alcohol. Thymapad® electrodes are single use only and must be discarded after thetreatment.
The Thymatron® System IV has no special requirements for restricted environment during transport orstorage, beyond Standard Sub-clause 10.1 criteria.

26

Thymatron® System IV Instructions for Use
EXPLANATION OF SIGNS AND SYMBOLSFRONT PANEL
Warning note: Caution observe accompanying paperwork

Defibrillation proof applied part type BF (“Body Floating”).
B-The device has a special protection against electric shock, especially in regard to thepermissible leakage current and the reliability of the protective earth conductor connection
F-The device has and insulated (floating) application part.

REAR PANEL

0344

Declaration of conformity with the provisions of council directive 93/42/EEC concerning
medical devices
CSA (“Canadian standard association”) certified device

Waste Electrical and Electronic Equipment. Do not throw in standard garbage. Recycle ordispose of equipment according to regulatory requirements of your country.

Adhere to manual

The device must only be opened by manufacturer or an authorized representative
Fuses

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Thymatron® System IV Instructions for Use
INSTALLATION
Unpack the instrument, open the black case, and place the instrument on a firm, flat surface such as a hospital
cart. Check the instrument for any damage, and make sure the rear panel voltage designation matches that of
the electrical outlet to be used. Determine that all manuals and items are present. If required, have the Safety
Check performed as described in the Service Manual, Section 2.
Connect the power cable to the rear of the unit. Power the unit on and observe that the POWER switch lightcomes on, the SELFTEST runs successfully, and “BASELINE” is displayed. Load a pad of thermal paper as
per the instructions inside the paper door (see page 12). Turn the power switch off and on again to verify thatthe recorder prints the date and software version. This completes the installation.

OPERATING INSTRUCTIONSThe Thymatron® System IV features two front panel controls for display and selection of all treatment
choices: the PERCENT ENERGY stimulus dose dial and the FLEXDIAL™ function and option selector.
In addition, you will see a POWER switch (power on/off), an IMPEDANCE TEST button, a START/STOP
button (to manually control the 4-channel printer), a TREAT button (to deliver the treatment stimulus), twoalphanumeric L.E.D.s (the left one with 8 characters, the right one with 4 characters), and 5 individual dot
L.E.D.s (to indicate activation of the FlexDial™ selection mode, activation of the Safety Monitor alarm,
activation of monitoring ECG in channel 4, and whether the preset program or a user set selection is in effect).

POWER ON/OFF
Be sure the power cable is plugged into a grounded, 3-prong hospital-grade socket. Press the top half of thefront-panel POWER switch (labeled “I”) to turn the unit on; press the bottom half of the POWER switch(labeled “0”) to turn the unit off.
SELF TESTThe Thymatron® System IV automatically tests the integrity of all circuits. When the unit is powered on, aflashing nonsense symbol appears for several seconds in the 8-character L.E.D., followed by the flashingmessage “SELFTEST” for a few seconds, then a self-test confirmation report is printed and the words “NOBASE” appear, indicating that baseline EEG collection still has yet to be accomplished. (See IMPEDANCETEST procedure section for baseline EEG collection.)
The printed SELF TEST confirmation report will appear on the paper strip as:
Thymatron® System IV S/N [serial number here]
Date - Time S-IV version [software version] / [the number 60 or 50 Hz]
The Thymatron® S/N line can be replaced with the hospital’s name (see page 30).
PERCENT ENERGY DIAL
The PERCENT ENERGY dial is used to select the treatment stimulus dose. This dial has three functions

28

Thymatron® System IV Instructions for Usethat are displayed in the 4 character L.E.D. above the dial.
1. Rotating the dial displays the PERCENT ENERGY settings for each stimulus dose, followed
by a brief display of the corresponding stimulus charge in mC.
2. Pressing the dial displays the stimulus program currently in effect.
3. Pressing, holding in and then rotating the dial enables the operator to rapidly change stimulus
programs without using the FlexDial™.
To display the corresponding charge in mC again, rotate the PERCENT ENERGY dial in either
direction and then back again to the desired setting.
LIGHT-EMITTING FUNCTION DISPLAYSThe Thymatron® System IV front panel has two alphanumeric L.E.D.s (the left one with 8 characters,
and the right one with 4 characters), plus 5 individual dot L.E.D.s.
The 8-character L.E.D. is located above the IMPEDANCE TEST button.
•

It displays the message “SELFTEST” immediately after the unit is powered on.

•

It displays the message “NO BASE” following completion of the self-test procedure and before
baseline EEG collection has been initiated.

•

It displays the message “TESTING” for 1 second when the IMPEDANCE TEST button ispressed. It then displays the static impedance value in ohms and maintains it until the button
is released.

•

It displays the message “BASELINE” from the time the IMPEDANCE TEST button isreleased until baseline EEG is obtained, about 6-10 seconds.

•

It displays the message “READY” when baseline EEG collection has been successfully accomplished.

•

After the “TREAT” button is pressed and released, it shows the time elapsed in seconds since
the end of the treatment stimulus.

•

It displays the flashing message “REPORT” when the START/STOP button is pressed togenerate and print the end-of-treatment report.

•

It displays the designations and values of all FlexDial™ functions and options during their selection.

The 4-character L.E.D. is located above the PERCENT ENERGY dial.
•

It displays the different PERCENT ENERGY values as the dial is rotated. It then briefly displays themC of charge corresponding to each PERCENT ENERGY dial setting.

•It displays the stimulus program in effect when the dial is pressed.

•

It displays the options for the stimulus programs when the dial is pressed, held in and rotated.
Releasing the dial selects that program.
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Thymatron® System IV Instructions for Use
Dot L.E.D.s are located on the front panel.
•

The L.E.D. labeled “FLEXDIAL” flashes when the FlexDial™ is activated.

•

The L.E.D. labeled “SAFETY MONITOR ACTIVATED” flashes when the Safety Monitor
has been activated.

•

The L.E.D. labeled “PRESET” lights when the LOW 0.5 program is in effect.

•

The L.E.D. labeled “USER SET” lights when a user set selection is in effect.

•

The L.E.D. directly above the “EEG/ECG/EMG” monitoring jack stays lit unless channel 4 isbeing used to monitor the patient’s ECG. When channel 4 is connected, the light goes off.

SAFETY MONITOR CIRCUIT ALARM TESTThe Thymatron® System IV has a Safety Monitor Circuit test button on the back panel labeled “ALARM
TEST”. This test can be performed annually or as hospital regulations require. The Safety Monitor Circuit
test is performed as follows:
1. Power on the Thymatron® System IV and connect the ECT stimulus cable.
2. Rotate the PERCENT ENERGY dial to any setting.
3. Connect the ECT stimulus cable banana plugs to a 200 ohm, 10 watt load resistor (or insert
these banana plugs into the designated jacks of the ECTOBRAIN™ II testing device).
4. First press and hold down the rear panel “ALARM TEST” button. Next, press and hold the“TREAT” button, and then release the “ALARM TEST” button.
5. Continue pressing the “TREAT” button while the Thymatron® System IV goes through the fullcycle of stimulus warning signal and stimulus indicator tones, then release the “TREAT” button.
At the end of the stimulus indicator tones the “SAFETY MONITOR ACTIVATED” dot L.E.D. will go on
and a high-pitched, continuous signal tone will sound until the unit is powered off. This shows the alarm
signal is operating correctly. If the indicator light and alarm signal tone do not occur, do not use the unit totreat patients until it has been examined and cleared by authorized biomedical personnel.
FRONT PANEL JACKSECT Stimulus JackThis 2-pin jack labeled “ECT” is located below and to the left of the IMPEDANCE TEST button. It
accepts the plug from the ECT stimulus cable.
EEG/ECG/EMG Monitoring JackThis 9-pin jack labeled “EEG/ECG/EMG” is located below and to the right of the IMPEDANCE TEST
button. It accepts the plug from the EEG/ECG/EMG monitoring cable.

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Thymatron® System IV Instructions for Use
It is impossible to insert the plug from the stimulus cable into the monitoring jack and viceversa. Forcing the wrong cable in will break the connector.

FLEXDIAL™ OPERATIONThe FlexDial™ has 18 different user-selectable functions, plus the ability to change EEG gain while theprinter is running. All functions and options can be displayed, then selected with alternating rotations andpresses of the FlexDial™, according to the following general principles:
1. Rotating the FlexDial™ in either direction provides a sequential display of all functions or options in thatparticular level. You can reach any other function or option in the same level by rotating the dial.
2. Pressing the FlexDial™ selects the function or option displayed in the 8-character L.E.D. and advances tothe next choice.
3. Pressing, holding in, and rotating the FlexDial™ while the printer is running allows the operator to rapidlychange the gain in all EEG channels.
To Enter FLEXDIAL™ Mode:
With power on, press the FlexDial™. The most recently selected function in the “SETTING” level will appear
in the 8-character L.E.D. The FlexDial™ dot L.E.D. will flash to indicate that you are now in the FlexDial™
mode.
These function headings (e.g., “SETTING”, “PROGRAMS”, “INDEXES”, etc.) do not change a particularsetting, but are the FlexDial™ locations from which to select a range of related options. For example,
selecting the “PROGRAMS” function, leads you to the options of: the traditional DGx program, three Low
Charge Rate programs, the Intermittent (Pulse Volley) stimulus mode, and the USER mode.
NOTE: Pressing the FlexDial™ will select the above program being displayed. Once a function or option is
selected with the FlexDial™ it remains in effect until changed, even when the unit is powered off.
To Exit FLEXDIAL™ Mode:
There are two ways to exit FlexDial™ mode: Pressing the START/STOP button of the printer orpressing the IMPEDANCE TEST button. The FlexDial™ dot L.E.D. will stop flashing upon exit.
1. Pressing the START/STOP button locks in the selection, generates a printed report of the 13
FlexDial™ selections in effect and exits the FlexDial™ mode.
2. Pressing the IMPEDANCE TEST button locks in the selections and exits the FlexDial™ mode
without generating a printed report.
FLEXDIAL™ Mode Procedure
For the remainder of this manual, selection of FlexDial™ functions and options will be shown by thefollowing shorthand notation with the explanation listed below:

31Thymatron® System IV Instructions for Use

FLEXDIAL™ [function] [options]•

Press the FlexDial™ to display the most recently adjusted FlexDial™ function.

•

Rotate the FlexDial™ in either direction to display the desired function.

•

Press the FlexDial™ to flash-display the option in effect for that function.

•

Rotate the FlexDial™ to flash-display the other options.

•

Press the FlexDial™ to select the desired option and advance to the next option (if there isone) or to return to FlexDial™ function level.

•

Press the IMPEDANCE TEST or START/STOP button to lock in the option and to exit the
FlexDial™ mode.

Example:FLEXDIAL™ CH 3-4 EMG-ECG, EEG-EEG means
1. Press the FlexDial™ to display the most recently-adjusted FlexDial™ function.
2. Rotate the FlexDial™ in either direction to display the “CH 3-4” function.
3. Press the FlexDial™ to flash-display the option in effect.
4. Rotate the FlexDial™ to flash-display the options, EMG-ECG or EEG-EEG.
5. Press the FlexDial™ to select the desired option and return to FlexDial™ function level, “CH 3-4”.
6. Press the IMPEDANCE TEST or START/STOP button to lock in the option and to exit the FlexDial™ mode.
FLEXDIAL™ Functions and What They Control
Function

Selects these options

SETTING

Resets to factory specifications, loads up to 8 user set selections

CHANN. 1

Channel 1 gain and position settings

CHANN. 2

Channel 2 gain and position settings

CHANN. 3

Channel 3 gain and position settings

CHANN. 4

Channel 4 gain and position settings

FREQUENC

Stimulus frequency (10 Hz – 70 Hz in 7 steps)

P-WIDTH

Stimulus pulsewidth (0.25 ms – 1.5 ms in 6 steps) (0.3 ms available)

PROGRAMS

Selects from 5 factory pre-programmed or user stimulus programs

SAVE USRStores up to 8 user set selections

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Thymatron® System IV Instructions for Use
CH 3-4

Enables channels 3-4 to monitor either EMG-ECG or EEG-EEG

ENDPOINT

Enables endpoint detection of EEG, EMG, HR measures, prolonged seizure alert
signal and Baseline Retention, BLV

INDEXES

Enables seizure quality measures

EEG FREQ

Selects one of three EEG measures

PRINTOUT

Enables printer and FFT printout, sets paper speed

UPLOAD

Enables sending treatment data to a PC automatically

DATA OUT

Reprints treatment just given; sends treatment data to PC

DATA IN

Accepts hospital’s name from PC for the printed report;
Accepts treatment data for re-printing treatment record

CLOCK

Sets month, day, year, hour, and minute on printed report

Additionally, pressing, holding in, and rotating the FlexDial™ while the thermal printer is runningwill change the gain in all EEG monitoring channels.
The 0.3 ms pulsewidth is available as an option at no charge. If the Thymatron® System IV has 0.3
pulsewidth enabled, please change all 0.25 in the manual listing to be 0.3.
If the 0.3 ms pulsewidth is enabled, there are no 0.25 ms pulsewidth settings. All other pulsewidths areavailable.
Flow Chart for FLEXDIAL™ controller: See Addendum IV.
PAPER LOADING INSTRUCTIONSThe Thymatron® System IV printer paper holder is located just below Somatics’ logo on the right sideof the front panel. Press the arrow on the top cover release bar to open the printer cover door. Remove
the cardboard sheets and place the fan folded paper pad inside. Make sure the black squares are on theright side and the warning strips on the bottom of the pad and to the left side. Feed a double sheet into
the printer, just below the roller. The printer will automatically advance the paper and stop. Press the
START/STOP button twice to feed the paper to the next black square. The display will show
“FORMFEED” when it advances to the next black square. The “FORMFEED” will always indicate thatthe paper will advance to the next black square and stop.
STIMULUS CABLE CONNECTION
Connect the plug of the black ECT stimulus cable into the jack labeled “ECT”, located on the lower
left front panel.
MONITORING CABLE CONNECTION
Connect the plug of the gray EEG/ECG/EMG monitoring cable into the jack labeled “EEG/ECG/EMG”,
located on the lower left front panel, just to the right of symbol of the human figure inside a box.
The Treatment and Monitoring Cables are not interchangeable. They cannot be inserted into
the wrong connector. However, forcing them into the wrong place will damage theconnectors or the cables.

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Thymatron® System IV Instructions for Use
LEAD-WIRE CONNECTIONSThe Thymatron® System IV is shipped with 9 standard length (24 inch) lead-wires: 4 red, 4 black, and 1
green. Also included are 2 extra length (60 inch) brown lead-wires for recording EMG from the leg, if desired.
Any combination of channels (from 1 to 4) can be used to monitor the patient. Not all channels need to be
used. However, channel 1 must be used to obtain baseline EEG and seizure endpoints.
Plug the red lead-wires into the receptacles for channels 1, 2, 3 & 4 indicated by red dots at the flared end of
the gray monitoring cable and plug the black lead-wires into the corresponding receptacles for channels 1, 2, 3
& 4 indicated by black dots. Plug the green lead-wire into the green receptacle marked “Iso Gnd”. If
monitoring EMG from the leg, insert the brown lead-wires into the channel 3 receptacles (in any order) insteadof the red and black lead-wires. The ordinary lifespan of a lead-wire is one year. With infrequent use somewill last longer. Replacement lead-wires are available separately from the entire monitoring cable.

SEIZURE MONITORING CONSIDERATIONS
Somatics’ stick-on, snap monitoring electrodes, [Cat. # EEDS] are ideal for EEG, ECG and EMG monitoring.
Their size and rectangular shape facilitate fronto-mastoid and bifrontal application without interfering with thestimulus electrodes. Prepare the skin sites by vigorously rubbing with an alcohol swab and wiping dry.
Polarity of recording electrodes can be important for EEG recording, so carefully follow the instructions
below. Each recording channel takes one negative and one positive lead-wire, designated as black and red,respectively. On the monitoring cable, the holes facing the label are designated red (positive), and those on theside opposite from the label are designated black (negative). The 2 long lead-wires for recording EMG fromthe foot are color- coded brown for quick recognition since polarity is not an issue with either EMG recording.
The green ground lead-wire always plugs into the green-coded socket labeled ISO-GRND; only one ground isrequired no matter how many channels you monitor.
MONITORING ELECTRODES APPLICATION
We recommend two-channel EEG monitoring because it takes full advantage of all the special and uniquemonitoring features of the Thymatron® System IV, and with the splitter included, requires only one morelead- wire than single-channel EEG monitoring. If you do choose single-channel EEG monitoring, we
recommend a left fronto-mastoid placement because it can demonstrate seizure generalization to the left
hemisphere when giving right unilateral ECT.
Regardless of how many channels you choose to monitor, Channel 1 must always be used for EEG in order toobtain a baseline EEG sample for the determination of the EEG endpoint and the EEG indexes, channel 3
must always be used to monitor EMG, channel 4 must always be used to monitor ECG, and the green ISOGRND channel must always be used for the ground.
The preferred 4-channel monitoring configuration using the splitter (EEG in channels 1 & 2, EMG in channel
3, and ECG in channel 4)
EEG: fronto-mastoid EEG electrode placements are recommended. Place a monitoring electrode in the centerof the forehead, another electrode over the left mastoid bone, and a third electrode over the right mastoid bone.
Plug the two narrow ends of the splitter into the black positions for channel 1 and 2. Then connect a black
lead- wire to the channel 1 position on the splitter, leaving the channel 2 position on the splitter empty.
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Thymatron® System IV Instructions for Use
Connect this black lead-wire to the top front forehead monitoring electrode. Connect two red lead-wires tochannel 1 & 2 red positions and clip the ends to the corresponding mastoid electrodes. Apply a monitoring
electrode to either shoulder as a ground and connect it to the green lead-wire.
ECG: The great advantage of monitoring ECG with the Thymatron® System IV rather than (or in addition to)equipment provided by the anesthetist is that you get a permanent record of the heart rate printed every threeseconds on the recording strip, plus an end-of-treatment printout of the baseline and peak heart rates, to help
you assess the efficacy of the seizure just given.
Apply two monitoring electrodes over the anterior chest above and below the heart, spaced about 8” apart.
Connect the channel 4 red and black lead-wires to the precordial electrodes in any order of polarity and insert inthe channel 4 holes.
EMG: The purpose of monitoring EMG is to provide an automated and highly accurate estimate of the motor
seizure duration. Apply two monitoring electrodes spaced about 3” apart to a limb that has been cuffed toprevent the effects of the muscle-relaxant drug. Connect the channel 3 red and black lead-wires in any orderof polarity to monitor from the patient’s arm and plug into the channel 3 holes. (Use the brown 60 inch leadwires to monitor from the patient’s foot, as illustrated.)
A 3-channel monitoring setup (EEG in channel 1, EMG in channel 3, and ECG in channel 4)
For the preferred left fronto-mastoid EEG configuration, place one monitoring electrode above the left
eyebrow and the other electrode over the left mastoid bone. Connect the channel 1 lead-wires to themonitoring electrodes in any order of polarity (no splitter is used), and connect the ECG and EMG electrodes,
ground electrode, and lead-wires as described above.
For 3 or 4-channel EEG monitoring (primarily used for research) use the electrode placements of your choice,remembering to keep the polarity (relationship of red and black lead-wires) consistent for corresponding
channels on each side of the head. If you connect the red and black lead-wires to frontal and temporalmonitoring electrodes, respectively, on the left side of the head, be sure to maintain the same polarity
relationship when connecting the corresponding pair of frontal and temporal electrodes on the right side of thehead. Apply a monitoring electrode to either shoulder as a ground and connect it to the green lead-wire clip.
CHANNELS 3 & 4 SELECTION
EEG is always monitored from channels 1 & 2 and they are not user selectable. Channels 3 & 4 canmonitor either EMG and ECG or two more channels of EEG. To select the monitoring options forchannels 3 & 4, follow the procedure below:
FlexDial™ CH 3-4 EMG-ECG; EEG-EEG

STIMULUS ELECTRODES APPLICATION
Instructions for legacy metal old type stimulus electrodes are in Addendum VI.
Apply Thymapad™ adherent stimulus electrodes [Cat. # EPAD] electrodes supplied with theThymatron® System IV according to the directions, “Use of Thymapad™ Disposable ECT Stimulus
Electrodes”. Clean the patient’s skin sites by rubbing vigorously with a saline moistened swab and pat
35

Thymatron® System IV Instructions for Use
dry. Do not use solvents (e.g., alcohol) with Thymapad™ stimulus electrodes. Spread 1-2 drops of PreTac solution over the site and rub into the skin with a fingertip until dry. Remove a Thymapad™ fromits wrapper, peel it from the plastic backing, and apply it firmly to the bare skin.
Insert the banana plug from the ECT stimulus cable into the plastic receptacle at the end of each
Thymapad™ wire, until the entire conducting surface of each banana plug is covered and no metalshows. Press firmly again on each Thymapad™ to ensure it is fully applied and then test the static
impedance. Impedance testing is necessary for safety.
For conventional bitemporal stimulus electrode placement, clean the skin sites over the temples asabove. Remove a Thymapad™ from its wrapper and apply it firmly to the bare skin of the temple. Applya second Thymapad™ to the other temple.
For bifrontal placement, place the center of each Thymapad™ 5 cm above the lateral angle of each orbit,
about 14-15 cm apart. Before peeling the Thymapad™ from the backing, bend it to match the shape ofthe skull at each electrode site.
For Swartz’ left-anterior right-temporal (LART) placement, place the left-sided Thymapad™ above theleft eye, with its lateral edge bordering the bony ridge between the forehead and the temple. Before
peeling the left Thymapad™ from its backing, bend it to match the forehead’s curve. Place the rightfrontotemporal electrode exactly as described above for bitemporal ECT.
For right unilateral stimulus electrode placement, the d’Elia placement is recommended. Clean and dry
the skin over the patient’s right temple as above. Remove a Thymapad™ from its wrapper, peel it fromits plastic backing, and apply it firmly to the bare skin at the right temple. Part the hair on the right sideof the head near the vertex and moisten the scalp thoroughly with a saline-soaked gauze pad or saline
solution spray. Patients with dense, wiry hair may require full saline saturation of the hair and scalp area
directly under the electrode. Apply a Thymapad™ to the site, holding it firmly in place with the special
foam handle applicator supplied. (If the patient is bald at the near-vertex site, the upper Thymapad™ canbe applied directly to the bare scalp after cleaning and drying as described above.)

IMPEDANCE TEST (FOR STATIC IMPEDANCE)
Static impedance testing is necessary for safety. Be sure the front panel POWER button is on, the ECT
stimulus cable connected to the front panel and both stimulus electrodes are firmly applied. Press thefront panel IMPEDANCE TEST button and observe the static impedance displayed in ohms, in the 8digit L.E.D. Repeatedly checking impedance does not prevent ongoing monitoring or affect baseline
EEG collection.

DO NOT PRESS THE “TREAT” BUTTON WHEN TESTING THE IMPEDANCE.
CAUTION36

Thymatron® System IV Instructions for Use
The static impedance test checks the quality of the skin-to-electrode contact. With the Thymatron® System IV,
the static impedance should be greater than 100 ohms and less than 3000 ohms before the treatment stimulus
dose is administered. A static impedance reading of less than 100 ohms suggests a short circuit, probably in thestimulus cable. An impedance reading of 3000 ohms or more appears as the flashing number 3000; if this occurs
the impedance should be reduced by the following steps:
Try pressing firmly on each Thymapad™ again while testing the impedance. This is especially important for thevertex electrode with unilateral ECT, which should be pressed vigorously in place with the foam handle
applicator provided. Also, for unilateral ECT, make sure that the hair and scalp under the vertex stimulus
electrode are thoroughly moistened with a saline-soaked pad.
If necessary, remove the Thymapad™, pass it under running water, shake off the excess water, wait a few
minutes and then reapply the Thymapad™ by pressing it firmly into place.
Check to make sure the electrodes have not slipped or twisted.
Reposition the stimulus electrodes to minimize the amount of hair underneath.
Increase pressure on the stimulus electrode by pressing harder with the foam handle applicator.
Gently rub the skin under the stimulus electrodes with a fine emery board or Skin Prep tape (3-M) to remove the
top layer of dead cells and sebum. Reapply the stimulus electrodes exactly as before.
A common reason for high impedance is that one or more steps were omitted from skin site preparation. Pleasebe sure to follow each instruction step when using Thymapad™ stimulus electrodes. During cold weather skin
thickens and hardens, causing the static impedance to rise. Also, some patients have high readings despite allprocedures. Try applying skin lotion to the electrode sites between treatments and shortly after waking on ECT
days.
If the static impedance reading remains >3000 ohms after trying the above procedures, try replacing each
Thymapad™, the lead-wires or the stimulus cable, in that order.

MOUTH PROTECTION
During the ECT stimulus and seizure the jaw muscles commonly clench tightly. This poses risks of tooth
fracture or displacement and biting of tongue and cheeks. These can cause mouth bleeding with pulmonary
aspiration of blood. These risks are mitigated by inserting a mouth protector prior to the electrical stimulus.
Somatics' mouth protectors have channels for ventilation and are available in reusable (sterilizable) and singleuse types. They are accompanied by instructions for insertion.

BASELINE EEG COLLECTION
Prior to collecting a baseline EEG, be sure the automatic EEG endpoint detection feature of the Thymatron®
System IV is enabled; the EEG monitoring electrodes are properly applied to the patient; the monitoring cable37

Thymatron® System IV Instructions for Use

with attached lead-wires is connected to the front panel; and the lead-wires are clipped to the monitoring
electrodes.
When the IMPEDANCE TEST button is pressed and held, the word “TESTING”, will briefly appear in the 8digit L.E.D. Then a number ranging from 0 to >3000 ohm, representing the static impedance, will appear.
When the IMPEDANCE TEST button is released, the number is replaced by the message “BASELINE”. The“BASELINE” message indicates that baseline EEG collection is in progress. When baseline EEG collection
has been accomplished, the word “READY” will appear in the L.E.D. It normally takes about 6-10 seconds
for “READY” to appear.
However, moving the patient’s head, touching or moving the monitoring electrodes, lead-wires, or monitoring
cable during baseline EEG collection will prolong the process by introducing EEG artifact. The less thepatient and monitoring connections are moved or touched during baseline EEG collection, the sooner the“READY” message will appear, and the patient will be ready to treat. If necessary, stop ventilating the patient
for the few seconds it takes for the “READY” message to appear. Place the lead-wires so that they will not be
disturbed by the anesthetist. Each pair of wires can be taped together about every 6 inches to minimize
movement and artifact.
NOTE: If the “READY” message does not appear before the treatment stimulus dose is administered, there
will be neither an Ictal Line™ nor EEG endpoint determinations nor seizure quality measurements because anadequate baseline was not obtained. However, the treatment itself will not be affected.
It is not necessary for the Thymapad™ stimulus electrodes to be applied in order to obtain a baseline EEG
collection. Do not be concerned with an impedance reading >3000 ohms when no stimulus electrodes havebeen applied; baseline EEG collection will proceed anyway. Static impedance will be tested after the stimulus
electrodes have been applied. Repeated pressing of the IMPEDANCE TEST button does not interfere withbaseline EEG collection.
TIP: It is strongly recommended to initiate baseline EEG collection by pressing the IMPEDANCE TEST
button on the Thymatron® System IV’s front panel as soon as the monitoring electrodes and a groundelectrode have been applied., even before applying the Thymapad™ stimulus electrodes (e.g., while thepatient is fully awake and before anesthesia has been administered). This will provide the longest possible
period of baseline EEG collection, maximizing the likelihood that a good baseline will be collected by thetime the treatment stimulus is administered.
STIMULUS DOSE SELECTION
The Thymatron® System IV is shipped with the LOW 0.5 program enabled. This is the recommended choicefor the first treatment in all patients for whom there is no prior information concerning ECT response or
seizure threshold. When desired, the FlexDial™ can be used to select stimulus parameters specifically tailoredto the patient’s established requirements, or to select from among other factory- or user- set stimulus
programs.
However, we recommend use of the LOW 0.5 program wherever possible, because it provides a broadly
effective stimulus that is in the physiological range for most patients.
Rotate the PERCENT ENERGY dial to display the available stimulus settings (range: 5% to 100% ENERGY in
38

Thymatron® System IV Instructions for Use
5% increments). Stop rotating the dial at the desired PERCENT ENERGY setting. A 1-second display thenappears of the charge (mC) that corresponds to the PERCENT ENERGY setting, followed by a return to the
PERCENT ENERGY number.
NOTE: The stimulus dose in mC that corresponds to any PERCENT ENERGY figure shown in the L.E.D. canbe viewed again for 1 second by rotating the PERCENT ENERGY dial to either side and then back again.
Because stimulus duration is limited to a maximum of 8 seconds, the higher PERCENT ENERGY settings
may not be available when the user selects pulsewidth or frequency values at the lower end of their ranges.
Whenever the PERCENT ENERGY setting for a given pulsewidth and frequency would deliver a stimulus
exceeding 8 seconds, the message “>8 S” will appear.
However, all the factory-programmed preset programs shown in the next paragraph will work at all
PERCENT ENERGY settings.
Table 1 in Addendum VII shows all the standard dosages and stimulus parameters for each PERCENT
ENERGY setting.

STIMULUS PROGRAMS: FACTORY PROGRAMMED
There are 5 factory set stimulus programs. The “LOW” programs automatically adjust the frequency toprovide the longest stimulus duration available for a given PERCENT ENERGY setting; providing the
optimum stimulus for each dose. The LOW 0.5 program is the only preset program that will show as“PRESET” on the front panel L.E.D. All of these factory set programs can go to 100% and 504 millicoulombs
where available.
DGX Reproduces the standard stimulus of the Thymatron® DGx
LOWEST Automatically adjusts parameters to provide the lowest charge rate
LOW 0.25 Fixed 0.25/0.3 ms pulsewidth varies frequency to maximize duration (1 – 100%)
LOW 0.5 Fixed 0.5 ms pulsewidth, varies frequency to maximize duration
INTERMIT Intermittent pulse-volley stimulus mimics the Siemens Konvulsator
Please see Addendum VII for the Program Tables for the frequencies, pulse widths, pulse numbers anddurations for each Energy setting.
STIMULUS PROGRAM SELECTION
Any standard (factory-programmed) setting can be selected using the procedure listed below. Or, to quickly
change programs without the FlexDial™, press, hold in and rotate the PERCENT ENERGY dial. Releasing it
selects the program displayed.
FLEXDIAL™ PROGRAMS DGX, LOWEST, LOW 0.25/0.3, LOW 0.5, INTERMIT, USER
Press and hold in the PERCENT ENERGY dial at any time to display the stimulus program in effect.
Release the dial to return to the PERCENT ENERGY display.

39Thymatron® System IV Instructions for Use
FREQUENCY SELECTION
When a factory-programmed preset stimulus is in effect, frequency is automatically adjusted for any
given PERCENT ENERGY setting. Selecting a specific frequency takes the Thymatron® System IV
out of any preset program. To select a specific stimulus frequency:
FLEXDIAL™ FREQUENC 10 to 70 Hz

PULSEWIDTH SELECTION
When a factory-programmed preset stimulus is in effect, the pulsewidth is automatically adjusted for any
given PERCENT ENERGY setting. Selecting a specific pulsewidth takes the Thymatron® System IV out ofany preset program. To select a specific stimulus pulsewidth:
FLEXDIAL™ P-WIDTH 0.25 (0.3) to 1.5 ms
Because stimulus duration is limited to a maximum of 8 seconds, the higher PERCENT ENERGY settings
will not be available when manually setting the 0.25 (0.3) ms pulsewidth, which will provide stimuli only up
to the 50% ENERGY. However, when the LOW 0.25 (LOW 0.3) program is in effect, stimuli of up to 100%
ENERGY can be delivered because, for this program only, the frequency can go as high as 140 Hz.

STIMULUS DOSE FOR BILATERAL, BITEMPORAL, BIFRONTAL, LART ECT
For the initial treatment, select the LOW 0.5 program. The PERCENT ENERGY dial should be set toapproximately one-half the patient’s age (e.g., 25% for a 50 year-old). If no seizure activity results, thePERCENT ENERGY setting should be increased to 100% and the patient re-stimulated within 30-60 seconds
to maximize the likelihood of obtaining a therapeutically satisfactory seizure at the first treatment session.
Before the next treatment day, the patient’s history and records should be reviewed to ensure that dehydration
or ingestion of sedative-hypnotic or anticonvulsant medications have not contributed to the difficulty inobtaining a good seizure. Consideration should be given at the next treatment session to administering astimulus dose at the patient’s age or at maximum charge.

STIMULUS DOSE FOR UNILATERAL ECTSatisfactory therapeutic results can be obtained with right unilateral ECT by simply setting the PERCENT
ENERGY dial to approximate the patient’s age in years (e.g., 75% for a 72 year-old patient). If asatisfactory seizure is not obtained to the initial stimulus with right unilateral ECT, proceed as described in
the paragraphs above for bilateral ECT.
NOTE: Once a patient obtains a satisfactory seizure with a given PERCENT ENERGY stimulus dose withunilateral ECT, we do not recommend administering subsequent treatments with progressively lower
settings in an attempt to deliver the smallest stimulus that will still induce a seizure. This is because
minimum stimulus dosing has been associated with inadequate therapeutic efficacy for right unilateral ECT.
STIMULUS TITRATION PROCEDURE
For those who prefer to set the initial stimulus dose relative to the seizure threshold, a simple and40Thymatron® System IV Instructions for Usepractical stimulus titration schedule for unilateral ECT starts with an initial setting of between 1% and
5% ENERGY, followed by re-stimulations at between 5% and 10% ENERGY. Increase increments
until a seizure occurs, to a maximum of 4 stimulations in a treatment session (on average, fewer than
three stimuli are required). Once the seizure threshold is determined for a specific PERCENT
ENERGY setting, the recommended dosing level for unilateral ECT is 4-6 times that threshold value(e.g., 60% to 90% ENERGY for a threshold value of 15% ENERGY).
Because seizure thresholds for bitemporal and bifrontal ECT are higher than those for right unilateral
ECT, the initial dose for stimulus titration with bitemporal ECT should be between 5% and 10%
Energy, with 5% ENERGY increments as described above. The subsequent treatments should be
administered at doses approximately 2 times this threshold (e.g., 40% ENERGY for a patient with
20% ENERGY seizure threshold).

“BENCHMARK” METHOD FOR SETTING AND ADJUSTING STIMULUS
Because neither seizure duration nor seizure threshold are systematically related to the clinical efficacy
of an ECT treatment, you may wish to consider regulating the stimulus dose according to a physiologicalmeasurement that has been reported to correlate with treatment response (the "target measurement").
Possible target measurements include Postictal Suppression Index (PSI), Maximum Sustained Power(MSP), or peak heart rate (PEAK HR).
Unlike stimulus threshold titration, the benchmark method does not require administering consecutively
increasing sub-threshold stimulus doses until a seizure is obtained. Rather, at the first ECT treatment a highenough stimulus dose is given to induce an expected vigorous and effective seizure in virtually all patients.
The value for the benchmark measurement reported in the end-of-treatment report for this first ECT treatment
is then used as a target for all subsequent treatments.
Selection of the initial stimulus dose for the benchmark method can be made by the fixed-dose method or anage-based method. A fixed dose of 75-90% ENERGY should be high enough for most patients, regardless oftreatment electrode placement. Alternatively, the PERCENT ENERGY dial can be set to the patient’s age forunilateral ECT, or to 50-75% ENERGY of the patient’s age for the various bilateral placements: bitemporal,
bifrontal, or LART.
Dosage should be adjusted for subsequent treatments to maintain the selected variable (PSI, MSP, peak HR)
within about 5% of the established target, keeping in mind the often dramatic rise in seizure threshold across acourse of treatment. Lower target values suggest that the treatment was less than fully effective; this might beacceptable for selected patients but is clearly a matter of medical judgment.
Of course, as everywhere in medicine, clinical response is overriding. Patients whose EEG or peak heart rate
reflect a high seizure quality at lower dosage levels, but who are not showing clinical improvement, might
benefit from higher doses. Those who are enjoying a satisfactory clinical response despite apparently poor
quality seizures may require no dose adjustment.

TYPICAL COURSE OF TREATMENT
A typical acute course of treatment is two or three ECT sessions per week for between 6 and 10 total

41

Thymatron® System IV Instructions for Use
sessions. Some patients may need more treatments to achieve maximum improvement. Patients withcatatonia of malignant severity may benefit from more frequent ECT sessions at the beginning of
their course.
TARDIVE SEIZURE
A tardive seizure is a seizure that occurs after the ECT session. It is sometimes called a delayed onset
seizure. It is rare but dangerous, and fatality can occur. When it begins after an ECT session earlier thatday clonus or worsening delirium may be seen. Anticonvulsant treatment is typically immediate andvigorous, such as full anesthesia with propofol. These patients should be considered for transfer to the
ICU because of high risk for sudden cardiopulmonary arrest, a risk that lasts several days.
A different presentation of tardive seizure is onset of seizure at an ECT session in response toanesthesia alone, without an electrical stimulus. This can be managed in the same way an ECT seizureis, with insertion of a mouth protector, vigorous ventilation and seizure monitoring. If the seizure lasts
longer than about 100 sec consider termination with propofol.

WORSENING OF PSYCHIATRIC SYMPTOMS
As with any treatment, some patients may show worsening along the course of ECT, and discontinuationof the treatment becomes a consideration. Patients showing worsening should be suspected of having
delirium from the treatment or from combination with a complicating medical condition such as
Parkinson's disease or a medication such as a sympathomimetic agent, aminophylline or L-DOPA. New
onset of a medical condition should be considered, e.g., pneumonia, pulmonary embolus, MI,nonconvulsive status epilepticus, urinary tract infection. Patients with motor retardation or poverty ofthought before ECT may show apparent worsening when ECT decreases these initial symptoms, withagitation, self-harm or suicidal behavior that should mitigate with further ECT; suicide risk can increaseduring this time. Unrecognized alcohol or substance use disorder with withdrawal symptoms can also
cause worsening during a course of treatment.
MANIC SYMPTOMS
Patients treated with ECT may experience manic symptoms (including euphoria and/or irritability,
impulsivity, racing thoughts, distractibility, grandiosity, increased activity, talkativeness, and decreased
need for sleep) or a worsening of the psychiatric symptoms they are being treated for. Manic symptoms
can appear during a course of ECT for major depression or catatonia. When the full syndrome of manic
episode develops during ECT this is sometimes treated by simply continuing the course of ECT.
Another possibility is to stop ECT and treat the manic episode with medications. Sometimes only
disinhibition, intrusiveness, overfriendliness, impatience or indiscreet behavior appear. This may
represent orbital-frontal syndrome rather than mania. Orbital-frontal syndrome typically clears
spontaneously within one to two weeks after the ECT course is over, but can take a month or two.
TREATMENT STIMULUS ADMINISTRATION
Flip up the clear plastic hinged cover over the “TREAT” button. Press and hold the button down until
the treatment light comes on and then goes off again. While the “TREAT” button is held down, thefollowing events will occur:

42

Thymatron® System IV Instructions for Use
1. A one second continuous tone warning signal comes on, during which no current is delivered. If the
impedance is >3000, the warning tone is extended to 3 seconds. If the “TREAT” button is still pressed,
the treatment will be delivered.
2.

The “TREAT” button lights up and an intermittent buzzing tone sounds while the current is being
delivered.

3. The “TREAT” button light and buzzing tone both turn off when the treatment stimulus ends. The“TREAT” button can then be released.
4. The Audible EEG™ seizure monitor is activated (unless the volume is turned off) and the 4-channel
printer automatically starts to provide a paper recording. If the printer is already running when thetreatment stimulus is delivered, the printer will stop and automatically resume when the stimulus currentends.
5. The 8-digit L.E.D. on the front panel automatically displays the number of seconds elapsed since
the end of the stimulus.
NOTE: It is important to continue pressing the “TREAT” button until the light and buzzing tone stop.
Releasing the button early terminates the stimulus and delivers a smaller charge than intended. However,keeping pressure on the “TREAT” button after the stimulus ends, will not deliver additional stimulation.
When holding the patient’s jaw or touching the patient, make sure electrically insulated gloves are used.
SEIZURE MONITORINGThe Thymatron® System IV allows the physician to monitor the physiological variables of EEG, E CG,
and EMG. The paper tracing provides the wave forms and beats per minute for the ECG. The E E G and
EMG also appear on the tracings, with additional information provided.
EEG SEIZURE MONITORING
1. The Audible EEG™ seizure monitor
2. The EEG paper recording
3. The Ictal Line™ seizure indicator
4. The EEG endpoint and indexes determined values

AUDIBLE EEG™ SEIZURE MONITOR
This feature operates automatically when the “TREAT” button is pressed and released. The knob marked“VOLUME” on the back panel controls the volume of the tone. To inactivate this feature, turn thevolume control knob all the way counterclockwise.
The pitch of the Audible EEG™ signal varies with the amplitude of the EEG. It will waver and warble
intensely and rapidly during the initial tonic phase. It becomes increasingly irregular, with superimposed

43Thymatron® System IV Instructions for Use
staccato bursts, during the clonic phase, and tends to correspond to each muscular contraction. Seizure
termination is marked by a change to a nearly steady tone with little modulation or variability. EachThymatron® System IV is supplied with a cassette tape guide for the interpretation of the Audible
EEG™ seizure monitor.

EEG PAPER RECORDING
1. Paper EEG recording prior to the treatment stimulus can be initiated (after the EEG electrodes havebeen properly applied) by pressing the “START/STOP” button on the front panel. This will provide a
paper record of the patient’s baseline recording. The printer stops during treatment stimulus
administration.
2. Automatic paper EEG recording begins or resumes when the treatment stimulus ends. The EEG
recording continues through ictal and postictal periods, until the “START/STOP” button is pressed,
which generates the end-of-treatment report.
NOTE: Obtaining a paper baseline EEG record does not replace the baseline EEG collection procedures
described above.
ICTAL LINE™ SEIZURE INDICATOR
After baseline EEG collection is completed by the Thymatron® System IV and the “READY” message
light appears, a thin black line is printed along the top of the paper recording strip when the EEG
amplitude exceeds a specified baseline value. An unbroken, solid black line reflects continuous seizure
activity. A broken or intermittent line reflects waxing and waning, or intermittent seizure activity.
Complete cessation of the black line reflects EEG seizure termination, as determined by theThymatron® System IV. Wait several seconds before pressing the “START/STOP” button to terminate
recording because the computer takes that long to process and report the seizure endpoints and indices.

ENDPOINTS AND INDICES
A unique feature of the Thymatron® System IV, (U.S. patents: 4873981, 4878498, 5269302 and
5871517), provides two computer-determined estimates of the duration of the induced seizure, derived
from the EEG and EMG data.
Automatic EEG Seizure Endpoint Determination
The Thymatron® System IV continuously monitors the EEG for the endpoint of seizur e activity andprints the EEG seizure duration, in seconds, on the end-of-treatment report, provided the baseline EEG
collection procedures have been properly followed and the “READY” message has appeared. (If thetreatment stimulus is administered before the “READY” message appears, automatic EEG analysis
will not occur, and the end- of-treatment report will state the message “Baseline not available.”)44

Thymatron® System IV Instructions for Use
In about 10-20% of ECT treatments, the EEG endpoint is not readily determined (Abrams, 1997). Thistypically occurs when paroxysmal activity decreases too gradually to provide a clear visual endpoint, or
when the immediate post-seizure EEG contains high amplitude activity. In these circumstances, inability
to detect a precise EEG endpoint is expected with any method of examination. The Ictal Line™ mightshow an on-again- off-again broken line pattern, and the end-of-treatment report might state: “EEG
Endpoint is not detected”.

Automatic EMG (Motor) Seizure Endpoint Determination
The Thymatron® System IV is shipped with the EMG monitor enabled in channel 3. When EMG
monitoring electrodes have been properly applied, the lead-wires and monitoring cable connected, then
EMG tracing automatically appears on the paper record after the treatment stimulus ends.
The Thymatron® System IV continuously monitors the EMG for motor seizure activity and prints the
EMG endpoint seizure duration in seconds, on the end-of-treatment report. Baseline EMG collection isneither required, nor possible, in obtaining this measure.

CAUTION

The computer-derived endpoint seizure duration measures, including the Ictal Line™ seizure
indicator, are derived solely by calculation and are provided to aid, not replace, the physician’s
judgment. It is possible for seizure activity to continue in the brain after any or all of the computerreports indicate seizure termination. It is also possible for artifact to be interpreted by the computer
programs as seizure activity.

GAIN AND POSITION SETTINGS
The factory preset “GAIN” and “POSITION” settings should produce the best results. For those who preferindividualized settings, please note that “POSITION” is always set after “GAIN”, because positioning of the
tracing on the recording paper depends on the amplitude or gain of the signal. Thus, it is always necessary to set
the “GAIN” in a specific channel before setting the “POSITION”.
Enter the FlexDial function and rotate to Channel (n) where (n) is 1,2,3 or 4.
Press the FlexDial to display the current gain setting for channel (n).

Setting the gain for channel number [n] to off turns off printing of that channel.
You can adjust the gain for channel number [n} to between 10 and 2000 (microvolts).
Push the FlexDial in to display the Position of the tracing.
Setting the Position for channel number [n] to Auto selects automatic positioning
Setting Position for channel number [n} to a value between 0 and 800 determines its position.

45

Thymatron® System IV Instructions for Use
Push the FlexDial in again to return to channel selection.
Push the Impedance Test Switch to lock in new settings for gain and position.

NOTE: The amplitudes of the tracings decrease as the gain numbers increase.

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Thymatron® System IV Instructions for Use
TURN OFF PRINTING IN A CHANNEL
To turn off printing in a given channel, set the gain for that channel to “OFF”. If a given channel has been turnedoff, the other channels should be set to the “AUTO” position in order to evenly space the remaining tracings on
the paper.

CHANGING EEG GAIN RAPIDLY
TIP: To rapidly change the gain in all EEG channels, while the printer is running, press, hold in and then rotate
the FlexDial™ to print successive new gain values on the paper chart; release the FlexDial™ to lock in thedesired value when it appears.

SEIZURE QUALITY MEASURESThe Thymatron® System IV provides 7 Seizure Quality Measures under the “INDEXES” function level that canbe individually enabled/disabled. EEG monitoring must be enabled to obtain these measures. Their names and
FlexDial™ designations are as follows:

Average Seizure Energy Index

ASEI ON/OFF

Postictal Suppression Index

PSI

ON/OFF

Maximum Sustained Power and

MSP

ON/OFF

COH

ON/OFFTime to Peak Power
Maximum Sustained Coherence andTime to Peak Coherence
Duke University Amplitude Measures DUKE ON/OFF

The AVERAGE SEIZURE ENERGY INDEX (ASEI) integrates the total ictal EEG power across the entire
seizure and divides the result by the total seizure duration.
The POSTICTAL SUPPRESSION INDEX (PSI) measures the percentage decrease in ictal EEG amplitude
immediately following seizure termination.
The MAXIMUM SUSTAINED POWER (MSP) measure reports the mean value of the 10-second EEG segmentwith the highest average power recorded during the seizure.

47

Thymatron® System IV Instructions for Use

TIME TO PEAK POWER is the time elapsed from stimulus termination to the point of maximum EEG power.
The MAXIMUM SUSTAINED COHERENCE (COH) measure reports the mean value of the 5-second
EEG segment with the highest average coherence recorded during the seizure.
TIME TO PEAK COHERENCE is the time elapsed from stimulus termination to the point of maximum
EEG coherence.
DUKE UNIVERSITY AMPLITUDE MEASURES display the amplitudes of the 3 seizure segments(early ictal, mid-ictal, and post-ictal) reported by Duke University investigators to correlate with ECT
treatment response.

BASELINE RETENTION
Baseline Retention, BLV, found under ENDPOINTS, is the length of time the EEG baseline will be kept
in memory after the treatment. It can be set from 0 - 5 minutes. After this time a new EEG baseline mustbe acquired. This feature is useful for re-stimulation without acquiring a new EEG baseline.
TO ENABLE/DISABLE SEIZURE QUALITY MEASURESFLEXDIAL™ INDEXES: AESI ON/OFF, PSI ON/OFF, MSP ON/OFF, COH ON/OFF, DUKE ON/OFF
In the “INDEXES” function level, repeatedly pressing the FlexDial™ will show a sequential flashingstatus display (ON/OFF) for ASEI, PSI, MSP, COH, and DUKE measures, in that order. Rotating the
FlexDial™ will flash-display the enable/disable (ON/OFF) options, for each index. Press the FlexDial™
to select “ON” or “OFF” for each index and advance to the next. When the last index (DUKE) isenabled/disabled the display returns to INDEXES function level.

EEG FREQUENCY MEASURESThe Thymatron® System IV provides a continuously updated display of the user’s choice of one of 3
additional EEG measures: the 95% Spectral Edge Frequency (the EEG frequency below which 95% of thetotal EEG power is found), the Median Frequency (the EEG frequency above and below which 50% of power
is found) and the Relative Delta Power (the % EEG power found in the delta bandwidth: 1.5–3.5 Hz).
FLEXDIAL™ EEG FREQ: SP. EDGE, MID FREQ, % DELTA
SP. EDGE

95% Spectral Edge Frequency

MID FREQMedian EEG frequency% DELTA

Relative EEG power in the delta bandwidth

When EEG FREQ is enabled with one of these options, baseline EEG collection has been obtained and48

Thymatron® System IV Instructions for Use
the “READY” message appears, the values are continuously displayed in the 8-character L.E.D. Afterseveral seconds, the “READY” is replaced with the letter “R” to the right of the EEG values being
displayed.

PRINTER PAPER SPEED SELECTION
The Thymatron® System IV is shipped with the paper speed set to 25 mm/sec. Alternate paper speeds of
10 mm/sec and 50 mm/sec may be selected or the printing turned off entirely, as follows.
FLEXDIAL™ PRINTOUT: PRINT 10, PRINT 25, PRINT 50
TURN OFF PRINTING ENTIRELYFLEXDIAL™ PRINTOUT: PRINTOFF

POWER SPECTRAL ANALYSIS (FFT) SELECTION
After the paper speed has been selected by rotating and then pressing the FlexDial™, the FFT option(“ON” or “OFF”) flash-displays. FFT (“Fast Fourier Transform”) is an algorithm for extracting
frequency information from the EEG signal to perform a Power Spectral Analysis that displays the E E G
frequencies in various bandwidths for advanced clinical or research purposes. The Thymatron® System
IV is shipped with the FFT printout disabled; to enable this feature:
FLEXDIAL™ PRINTOUT: FFT ON, FFT OFF
USER SPECIFIED FLEXDIAL™ SELECTIONSThis feature allows the user to save and then recall up to 8 user-specified FlexDial™ selections in theThymatron® System IV memory. Individual doctors’ preferred range of FlexDial™ settings can besaved as “USER” selections, or specific FlexDial™ settings within a factory program can be saved,(e.g., turn channel 4 “OFF” and “UPLOAD” automatically.) Once the different user-specified selections
have been made and locked in by pressing the IMPEDANCE TEST button or the START/STOP button,
they may be saved as a USER selection as follows:
FLEXDIAL™ SAVE USR : SAVE US1-SAVE US8
After they have been saved, these user-specified selections can be recalled using the “SETTING” function ofthe
FlexDial™ shell by selecting from the options “SET US1” through “SET US8”. Be sure to remember orwrite down which number this specific configuration was saved as, so it can easily be recalled.
FLEXDIAL™ SETTING : SET US1 – SET US8When a user-specified FlexDial™ selection is in force, the “USER SET” dot L.E.D. on the front panel willlight.
RESET FLEXDIAL™ SETTINGS TO FACTORY VALUES

49

Thymatron® System IV Instructions for Use
The factory-programmed values listed below for the 13 FlexDial™-selectable settings can be reset as agroup as follows: Simply push the FlexDial™ three (3) times and press the Impedance Switch.
FLEXDIAL™ SETTING: RESET SETTING including channel Gain (G) and Position (P)Chann. 1… ....... G1--200 μV; P1--AUTO
Chann. 2…….…G2--200 μV; P2-AUTO Chann. 3…….…G3--1000 μV;
P3--AUTO Chann. 4…….…G4--1000
μV; P4--AUTO
FREQUENC .... Variable with LOW 0.5 program
P-WIDTH ........ 0.5mS
PROGRAMS….LOW 0.5
program CH. 3-4…
........................ EMGECGENDPOINT……EEG-ON; EMG-ON; HR-ON; PHR-ON; ESAOFF; BLV-2 INDEXES

ASEI-ON; PSI-ON; MSP-ON; COH-

ON; DUKE-OFF
EEG FREQ……FREQ. OFFPRINTOUT……PRINT-25;
FFT-OFF UPLOAD LOAD OFF
TIP: To quickly reset all values to factory settings right after the “SELFTEST” has been performed at power -on,press the FlexDial™ three times in a row, then press the IMPEDANCE TEST button.
To print a report showing all the FlexDial™ settings in effect at any given time, simply press the FlexDial™ to
enter any function level and then press the START/STOP button.

TRANSFERRING DATA BETWEEN A PC AND THYMATRON® SYSTEM IV
The Thymatron® System IV allows the operator either to send data (upload) or to receive data (input or
download) from a personal computer. The data transfers all require using the GENIE™ IV software tool,50

Thymatron® System IV Instructions for Use
which is included with the Thymatron® System IV. The data can be alphanumeric, such as the name ofthe hospital or patient information, or it can be digitized EEG, ECG, or EMG.
With the exception of the hospital’s name, all data to be downloaded must have been first uploaded to a
PC using the GENIE™ IV software tool. One reason for downloading this data to the Thymatron®
System IV would be to print a paper copy of an earlier treatment.
NOTE: All procedures listed below require the GENIE ™ IV software tool to be installed on a PC
connected to the Thymatron® System IV through the rear panel RS 232 serial port and the GENIE™ IV
software program opened to the proper section. Please consult the GENIE™ IV manual for further
details.

INPUT HOSPITAL NAME FOR THE PRINTED REPORTThis name will replace the Thymatron® System IV, S/N line on the start-up report.
FLEXDIAL™ DATA IN: DATA IN
1. Press the FlexDial™ to display the most recently adjusted FlexDial™ function.
2. Rotate the FlexDial™ until “DATA IN” is displayed.
3. Press the FlexDial™ once; “DATA IN” will flash-display.
4. Press the FlexDial™ again; “IN” will flash-display.

5. On the PC, from the GENIE™ IV software main menu, click on CONNECT

SEND NAME.

6. Type in hospital name in the “Name to Send” box and click “Send”.
7. Press the “IMPEDANCE TEST” or “START/STOP” button to exit the FlexDial™ mode.
DOWNLOAD PRE-RECORDED TREATMENT DATA FROM PC FOR REPRINTING BY
THYMATRON® SYSTEM IV
FLEXDIAL™ DATA IN: DATA IN
This feature allows for previously recorded treatment data to be sent back to the Thymatron® System
IV. Once the data has been received back in the Thymatron® System IV, it can then be reprinted using
the “REPRINT” option in the “DATA OUT” function level.
1.

Press the FlexDial™ to display the most recently adjusted FlexDial™ function.

2.

Rotate the FlexDial™ until “DATA IN” is displayed.

3.

Press the FlexDial™ once; “DATA IN” will flash-display.

4.

Press the FlexDial™ again; “IN” will flash-display.

5. On the PC, from the GENIE™ IV main menu, click on FILE OPEN. Highlight the file to be sent andclick OPEN. From the main menu, click on CONNECT SEND DATA.
51

Thymatron® System IV Instructions for Use
6. Transfer is complete when the display stops flashing and returns to “DATA IN”.
7. Press the “IMPEDANCE TEST” or “START/STOP” button to exit the FlexDial™ mode.
This treatment data will now replace that of the last treatment given and will stay in the Thymatron®
System IV memory until the unit is turned off or another treatment is given. To reprint this treatment on
a paper record, see the DATA OUT section below.
UPLOAD TREATMENT DATA AUTOMATICALLY TO A PC
This feature allows for the automatic transfer of the treatment data to a PC after the printed end-oftreatment report. The PC must be connected to the Thymatron® System IV and the Genie™ IV softwaretool opened to the correct function; please review the GENIE™ IV manual for further details. The
options are as follows:

LOAD OFF

Disables UPLOAD function and no data will be transferred.

LOAD RAW Sends all EEG data, including the FFT points and end-oftreatment report. LOAD FFTSends all FFT points and end-of-treatment report.
LOAD TXT

Sends ASCII file of the end-of-treatment report.

FLEXDIAL™ UPLOAD: LOAD OFF, LOAD RAW, LOAD FFT, LOAD TXT
1.

Press the FlexDial™ to display the most recently adjusted FlexDial™ function.

2.

Rotate the FlexDial™ until “UPLOAD” is displayed.

3.

Press and rotate the FlexDial™ to flash-display the above options.

4.

Press the FlexDial™ to select the desired option, usually “LOAD RAW”.

5.

Press the “IMPEDANCE TEST” or “START/STOP” button to exit the FlexDial™ mode.

After the patient is treated and the end-of-treatment report is printed, the Thymatron® System IV isready to send the data to the PC. Make sure all the connections are correct and the GENIE™ IV softwaretool is opened. From the GENIE™ IV main menu click on CONNECT AUTO UPLOAD. A small
screen will pop up showing the progress of the transfer. When the transfer is complete a new REPORT
screen pops up with the treatment date and time.
Note: The transferred file will be automatically saved as the “date and time” of the treatment. This file
can then be renamed and saved under the proper patient’s file by selecting from the GENIE™ IV main
menu FILESAVE AS.
DISPLAY EEG/EMG/ECG ON THE PC SCREEN

52

Thymatron® System IV Instructions for Use
This feature allows for real-time display of all enabled EEG/EMG/ECG channels via the PC screen,
providing a constantly updated display of the actual EEG/EMG/ECG tracings before and after thetreatment stimulus has been administered. This display will not affect the printed paper recording.
Before starting to display, make sure all the connections are correct and the GENIE™ IV software tool is
opened. From the GENIE™ IV main menu, click on WINDOW GRAPH. From the main menu, click on
TOOLS PLAY CONTROL and then TOOLS CHANNEL SETTING. Adjust the size of the graph screen
to allow for these two pop up screens. To start the display, follow the procedure below:
1. Press the IMPEDANCE TEST button to begin sending data.
2. Click on MONITOR in the PLAY CONTROL section.
The display will stop while the treatment stimulus is given with the “TREAT” button and it willautomatically re- start after the stimulus is completed. The display function will not interfere with thepaper recording function as both will proceed at the same time. When the “START/STOP” button ispressed, the display will also stop.
NOTE: To combine the display and automatic upload features, go to the GENIE™ IV main menu, click
on CONNECT AUTO UPLOAD. A small screen will pop up with the date & time for the name. Re-namethe file using the patient’s information, if desired and click UPLOAD. From the GENIE™ IV main
menu, click on WINDOWS GRAPH and then TOOLS PLAY CONTROL and TOOLS CHANNELSETTING as above.
OUTPUT TREATMENT DATA MANUALLY
This feature allows for manual transfer of the treatment data after the end of a given treatment. The
Thymatron® System IV stores only the last treatment in memory. If the unit is turned off or anothertreatment is given before data transfer, this data will be lost. This feature can be used when an
occasional treatment is to be stored on the PC. Make sure all the connections are correct and the
GENIE™ IV procedures are followed. Please review the GENIE™ IV manual. The options for “DATAOUT” are:
REPRINT
Reprints a complete record of the treatment just given or can be used to reprint thetreatment data just received from the PC.
RAW DATA

Sends all data including the FFT points and end-of-treatment report. FFT DATA
Sends the FFT points and end-of-treatment report.

RESULTS

Sends ASCII files of end-of-treatment report.

RETURN

Returns to the DATA OUT function level of the FlexDial™.

FLEXDIAL™ DATA OUT: REPRINT, RAW DATA, FFT DATA, RESULTS, RETURN
1. Press the FlexDial™ to display the most recently adjusted FlexDial™ function.
2. Rotate the FlexDial™ until “DATA OUT” is displayed.
3. Press and rotate the FlexDial™ to flash-display the options listed above.

53

Thymatron® System IV Instructions for Use
4. Press the FlexDial™ to select the desired option, usually “RAW DATA”.
5. The message “OUT” appears as the data is transferred to the computer.
6. If no treatment data is stored in memory the message “EMPTY” will flash and no data transfer will occur.
7. From the GENIE™ IV main menu, click on CONNECT RECEIVE DATA. The small pop up screen
will display the transfer progress. When finished, a new pop up screen, REPORT will contain the data.
This file may be saved using the main menu FILE SAVE AS feature.
8. When the transfer is complete, the FlexDial™ display returns to “DATA OUT”.
9. Press the “IMPEDANCE TEST” or “START/STOP” button to exit the FlexDial™ mode.
REPRINT THE LAST TREATMENTThe Thymatron® System IV automatically stores the last treatment in memory. If the recording paper
runs out or is damaged, the last treatment can be reprinted using this feature. This “REPRINT” feature
also allows for the reprinting of the treatment data just transferred to the Thymatron® System IV fromthe PC. In either case, the only treatment reprinted will be the last one in the memory.
Please note, if the Thymatron printer is re-started after the last treatment is printed and it runs for overthirty (30) seconds, that data will be considered the last treatment and the previous treatment just printed
before the re- start will be deleted from memory. Also, if the unit is turned off, another treatment istransferred from the computer or another treatment is given, the earlier treatment data will be lost. The
procedure for reprinting the treatment data is:
FLEXDIAL™ DATA OUT: REPRINT
While the treatment data is being reprinted, the “REPRINT” message will flash until all the data has
been reprinted, after which the printer will automatically stop, providing the original data contained an
end-of- treatment report.
SET DATE & TIME IN PRINTED REPORTTo change/reset the time or date, use the following procedure. Enter the FlexDial™ mode, rotate to the“CLOCK” function level and then alternate pressing and rotating the FlexDial™ to make the following
selections:
FLEXDIAL™ CLOCK: MONTH DAY YEAR HOUR MIN
MONTH

01 - 12DAY

01 - 31YEAR

00 - 99

HOUR

00 - 24

MIN

00 – 6054

Thymatron® System IV Instructions for Use
ELECTROMAGNETIC COMPATIBILITY (EMC)
GENERAL NOTES
1. An externally generated artifact is indicated if all the channels exhibit the same pattern superimposed on orinterfering with the signal. Try repositioning the electrode leads to eliminate this pattern.
2. A power mains artifact is indicated if all channels exhibit a thick solid line. Try repositioning the electrodeleads to eliminate this.
3. A large static discharge may cause the system to reset. The system would go through the “SELFTEST” again
and be ready to treat in about five seconds. To minimize static electricity, make sure to maintain sufficienthumidity in the treatment room and have a good grounding system on your mains.
4. A large high frequency pulse (e.g., as from electromagnetic imaging equipment) may cause the system toreset. The system would go through the “SELFTEST” again and be ready to treat in about five seconds. If thisoccurs make sure to identify the device(s) producing these pulses and maintain sufficient distance between theThymatron® System IV and the device(s) to prevent reoccurrence; if this is not possible, shielding may berequired.
5. This medical electrical equipment needs special precautions regarding Electromagnetic Compatibility (EMC)
and needs to be installed and put into service according to the EMC information provided in this chapter.
6. Portable and Mobile RF communications equipment can affect medical electrical equipment.
LIST OF CABLES AND ACCESSORIES
Article Number
Description#ECET-P

ECT Treatment Cable, black, Thymatron® System IV Plastic connector#ECEF-4

EEG/ECG/EM Monitoring Cable, gray, for System IV Plastic connector#ELDSC-9

Monitoring Lead Wires for Thymatron® System IV, 24” leads, set of 9

#ELDS-BR

Monitoring Lead Wires for Thymatron® System IV, 60” leads, set of 2

#ELDS-SPMonitoring Lead Wire, Splitter, two wires into one#ERTH

Remote Treatment Handle / Cable

CAUTIONUse of accessories and cabling other than those specified above, with the exception of those soldby Somatics LLC or its authorized representatives as replacement parts, may result in increased
emissions or decreased immunity of the Thymatron ® System.

55Thymatron® System IV Instructions for Use
ELECTROMAGNETIC EMISSIONS
Guidance and manufacturer’s declaration – electromagnetic emissions

Thymatron® ECT Systems are intended for use in the electromagnetic environment specified below. The
customer or the user of a Thymatron® System should assure that it is used in such an environment.
Emissions Test

Compliance

RF emissions
Group 1CISPR 11

RF emissions
Class ACISPR 11

Electromagnetic Environment - GuidanceThymatron® Systems use RF energy only for internal functions.
Therefore, RF emissions are very low and are not likely to cause any
interference in nearby electronic equipment.

Thymatron® Systems are suitable for use in all establishments other thandomestic and those directly connected to the public low-voltage power
supply network that supplies buildings used for Domestic purposes.

Harmonic emissions,
IEC 61000-3-2Class A

Voltage fluctuations/
Complies
flicker emissions
IEC 61000-3-3

CAUTIONThymatron® System should not be used adjacent to or stacked with any other equipment. If
adjacent or stacked use is necessary, performance of the Thymatron® System should be observed
to verify normal operation in the configuration in which it will be used.

56

Thymatron® System IV Instructions for Use
ELECTROMAGNETIC IMMUNITY
Guidance and manufacturer’s declaration – electromagnetic immunity
Thymatron® ECT Systems are intended for use in the electromagnetic environment specified below. The
customer or the user of a Thymatron® System should assure that it is used in such an environment.
IEC 60601 –Immunity Test
Compliance level Electromagnetic Environment - Guidance
Testing level
Electrostatic
discharge (ESD)
IEC 61000-4-2

Electrical fasttransient/burst
IEC 61000-4-4

Surge
IEC 61000-4-5±15 kV (Air)±8 kV (Contact)±1 kV for In/Out
ports±2 kV for Power EFT’s may cause artifacts on the printed
waveforms. These can be differentiated fromports
physiological waveforms. To minimize these±1 kV for In/Out effects, mains power quality should be that of a
ports
typical commercial or hospital environment.

±1 kV Differential
Mode±1 kV Differential
Mode
Mains power quality should be that of a typical±2 kV Common
Mode±2 kV Common
Mode±2 kV for Power
ports

0% UT for 0,5 cycles
Voltage dips, short
0% UT for 1 cycle
interruptions and
70% UT for 25
voltage variations on
cyclespower supply input
0%U
T for 250
lines
cyclesIEC 61000-4-11
Power frequency(50/60 Hz) magnetic
fieldElectrostatic discharge over air at ±15 kV
required in some cases a system re-start. After±8 kV (Contact) the system restart the system returned to normal
mode of operation.
±8 kV (Air)30 A/mFulfilledcommercial or hospital environment.

Mains power quality should be that of a typicalcommercial or hospital environment. If theThymatron® System shall be used continuously
during mains power interruptions, it isrecommended to power it from anuninterruptible power supply.
Power frequency magnetic fields should be atlevels characteristic of typical commercial or
hospital environment.

REMARK: UT is the main alternating voltage prior the application of the testing level57

Thymatron® System IV Instructions for Use
Guidance and manufacturer’s declaration – electromagnetic immunity
Thymatron® ECT Systems are intended for use in the electromagnetic environment specified below. The
customer or the user of a Thymatron® System should assure that it is used in such an environment.
IEC 60601 –Compliance
Immunity Test
Electromagnetic Environment - Guidance
Testing level
level
Portable and mobile RF communications equipment should be
used no closer to any part of the Thymatron® System,
including cables, than the recommended separation distancecalculated from the equation applicable to the frequency of thetransmitter.
Recommended separation distance:

Conducted HF
disturbances

3Vrms 150kHz V1 = 3 Vrms
to 80MHzIEC 61000-4-6
Radiated HF
disturbances
IEC 61000-4-3

3V/m 80MHz to E1 = 3 V/m
2,5GHzWhere P is the maximum output power rating of thetransmitter in watts (W) according to the transmitter
manufacturer and d is the recommended separation distance inmeters (m). Field strengths from fixed RF transmitters, as
determined by an electromagnetic site survey, a should be lessthan the compliance level in each frequency range. b
Interference may occur in the vicinity of equipment marked
with the following symbol.

Note 1: At 80 MHz and 800 MHz, the higher frequency applies.
Note 2: These guidelines may not be applicable in all cases. Electromagnetic propagation is affected byabsorption and reflection from structures, objects and people.
a Field strengths from fixed transmitters, such as base stations for radio (cellular/cordless) telephones and land
mobile radios, amateur radio, AM and FM radio broadcast cannot be predicted theoretically with accuracy. To
assess the electromagnetic environment due to fixed RF transmitters, an electromagnetic site survey should beconsidered. If the measured field strength in the location in which the Thymatron® System is used exceeds theapplicable RF compliance level above, the Thymatron® System should be observed to verify normal operation.
If abnormal performance is observed, additional measures may be necessary, such as reorienting or relocating
the Thymatron® System.
b Over the frequency range 150 kHz to 80MH, field strengths should be less than [V1] V/m.

58

Thymatron® System IV Instructions for Use
Recommended separation distances between portable and mobile RF communications
equipment and the Thymatron® System

Thymatron® ECT Systems are intended for use in the electromagnetic environment in which radiated RF
disturbances are controlled. The customer or the user of the Thymatron® System can help prevent
electromagnetic interference by maintaining a minimum distance between portable and mobile RFcommunications equipment (transmitters) ant the Thymatron® System as recommended below, according to the
maximum output power of the communications equipment specified below. The customer or the user of a
Thymatron® System should assure that it is used in such an environment.

Rated maximum
output power oftransmitter

Separation distance according to frequency of transmitterm
150 kHz to 80 MHz
80 MHz to 800 MHz
800 MHz to 2,5 GHz

W
0,01
0,1
1,0

0,12
0,38
1,2
3,8

0,12
0,38
1,2
3,8

0,23
0,73
2,3
7,3

10
12
12
23
100
For transmitters rated at a maximum output power not listed above, the recommended separation distance d inmeters (m) can be estimated using the equation applicable to the frequency of the transmitter, where P is the
maximum output power rating of the transmitter in Watts (W) according to the transmitter manufacturer.
Note 1 At 80 MHz and 800MHz, the separation distance for the higher frequency range applies
Note 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption
and reflection from structures, objects and people.
Note 3 Stated separation distances will assure safe operation of the Thymatron® System. However some noise
may be present on the printed waveforms.

59

EC DECLARATION OF CONFORMITY
To the Medical Device Directive 93/42/EEC

SOMATICS, LLC.
720 Commerce Drive
Venice, Florida 34292 USA

Represented in EEC by Schwind Benelux Medical Electronics B.V.,
Benedendorpsweg 117, 6862 WE Oosterbeek, The Netherlands

Declares that the distributed CE marked products conform to the types covered by the
EC Certificate Number 86253CE01, issued by DEKRA,
in accordance with Annex II of the Medical Directive 93/42/EEC
In addition, we ensure and declare that the distributed CE marked products,
as mentioned and falling within Class IIb meet the provisions of
the EC-Directive which apply to them.

This declaration is based on the application of the Quality System approved forthe manufacture and final inspection of the products concerned, in accordance with Annex II of the EC-Directive.
The conformity of the production quality assurance set out in Annex II.

This declaration is supported by the Quality System certification based on theharmonized standards ISO 13485:2016
Quality System Certificate No. 3819575

This Declaration of Conformity covers Thymatron Electroconvulsive Therapy Devices and is valid for all products
distributed by Somatics, LLC. bearing the CE mark, including the Thymatron® System IV, starting with serial No. 40020
and Thymatron System® II, starting with serial No. 40236 and ending with serial No. 41950

62

Thymatron® System IV Instructions for Use
INDEXA
ADDENDUM I (FIRMWARE CHANGES) 65
ADDENDUM II (ELECTRODE PLACEMENT) 67
ADDENDUM III (INSTRUCTIONS TO PATIENT) 73
ADDENDUM IV (FLEXDIAL FLOW CHART) 77
ADDENDUM V (MOCA TEST) 78
ADDENDUM VI (INSTRUCTIONS FOR LEGACY METAL OLD TYPESTIMLUS ELECTRODES) 79
ADDENDUM VII (TABLES OF STIMULUS DETAILS) 81
Adverse Events 9-10
Audible EEG™ seizure monitor 44, 45

Bbaseline EEG 28, 29, 34, 35, 37, 38, 39, 45, 46, 50
Baseline Retention 33, 49
Benchmark Method for Setting and Adjusting
Stimulus 42

C
CHANGING EEG GAIN RAPIDLY 48
CHANNELS 3 & 4 SELECTION 36D
DISPLAY EEG/EMG/ECG ON THE PC SCREEN 54
Duke University 26, 48, 49

E
EC DECLARATION OF CONFORMITY 63
EEG FREQUENCY MEASURES 49
EEG monitoring electrodes 38
EEG seizure duration 46
EEG Seizure Endpoint Determination 46
EEG SEIZURE MONITORING 45
ELECTROMAGNETIC COMPATIBILITY (EMC) 57
EMG (Motor) Seizure Endpoint Determination 46
EMG endpoint seizure duration 46
ENABLE/DISABLE SEIZURE QUALITY MEASURES 49
Enter FLEXDIAL™ Mode 31
Exit FLEXDIAL™ Mode 32
EXPLANATION OF SIGNS AND SYMBOLS 27

F
FFT 50FLEXDIAL™ [function] [options] 32
FLEXDIAL™ Functions and What They Control 33
FLEXDIAL™ Mode Procedure 32
FLEXDIAL™ OPERATION 31
FREQUENCY SELECTION 41
FRONT PANEL JACKS 31

G
GAIN AND POSITION SETTINGS 47

I
Ictal Line™ Seizure Indicator 45
IMPEDANCE TEST (FOR STATIC IMPEDANCE) 37
Input Hospital Name 52
INSTALLATION 28
INTENDED USE 6

L
LEAD-WIRE CONNECTIONS 34
LIGHT-EMITTING FUNCTION DISPLAYS 29

M
MAXIMUM SUSTAINED COHERENCE 49
MAXIMUM SUSTAINED POWER 48
Median EEG frequency 49
Median Frequency 26, 49
MONITORING CABLE CONNECTION 34
MONITORING ELECTRODES APPLICATION 35

O
OPERATING INSTRUCTIONS 28
Output Treatment Data Manually 55

P
PAPER LOADING INSTRUCTIONS 34
PERCENT ENERGY DIAL 29
Postictal Suppression Index (PSI) 42

61

Thymatron® System IV Instructions for UsePrecautions 7-9
Printer Paper Speed Selection 50
Program Selection 40
PULSEWIDTH SELECTION 41

R
REFERENCES 19

STIMULUS DOSE FOR BILATERAL 41
STIMULUS DOSE FOR UNILATERAL 41
STIMULUS DOSE SELECTION 39
STIMULUS ELECTRODES APPLICATION 36
STIMULUS OUTPUT 25
STIMULUS PROGRAM SELECTION 40
STIMULUS TITRATION 42
STIMULUS TITRATION PROCEDURE 42

Reprint the Last Treatment 56
RESET 51RESET FLEXDIAL™ SETTINGS TO FACTORY VALUES 51

S
SAFETY INFORMATION 7
SAFETY MONITOR CIRCUIT ALARM TEST 30
SEIZURE MONITORING 25, 35, 44
Seizure Quality Measures 26, 48
SET DATE & TIME IN PRINTED REPORT 56
Side effects 11, 17
SIGNS AND SYMBOLS 27
SPECIFICATIONS 25
Spectral Edge Frequency 26, 49
Stimulus cable 34
STIMULUS CABLE CONNECTION 34

T
The AVERAGE SEIZURE ENERGY INDEX (ASEI) 48
TRANSFERRING DATA 52
TREATMENT STIMULUS ADMINISTRATION 44
Turn off printing 48
TURN OFF PRINTING ENTIRELY 50U
UPLOAD TREATMENT DATA AUTOMATICALLY TO A PC 53
USER SPECIFIED FLEXDIAL™ SELECTIONS 50

W
Warnings 7

62

Thymatron® System IV Instructions for Use
ADDENDUM I (FIRMWARE CHANGES)
History of Firmware Changes to THYMATRON® SYSTEM IV

The software version of your Thymatron® System IV is printed at power-up.
Each of the following software upgrades includes all previous upgrades.
SOFTWARE
VERSIONDATE

DESCRIPTIONREQUIRESGENIE VERSION

4.31

6/1/99Initial software

4.5

4.32

6/15/99 Made DOS-compatible

5.00

9/1/00Added Real time PC monitoring
Palm® connection.

5.0

5.10

5/1/01

Added Diagnostic messages for EEG endpoint.

5.0

5.20

8/1/01

Added LOW 0.25 program

5.0

5.30

5/1/02

Added Automatic upload to PC
SEI upgraded to ASEI, SGI retired
Impedance test increased to 800 Hz.

6.3

5.40

11/15/02

Added EEG Frequency Measures

6.3

5.41

2/1/03Eliminates need for recalibration
after chip upgrade.

6.3

5.50

7/1/04

Improved algorithm for PSI
Change program via Percent Energy Dial
Change EEG gain while recording
2X Dose, (where available)

6.3

5.60

6/15/09 Adjusted baseline retention (BLV), 0-5 minutes
Reset EEG Baseline when pushing Impedance
Test & Energy Buttons simultaneously
Either 0.25 or 0.3 pulsewidths & 2X-LP

6.3

5.61

12/1/09 USER programs display up to 70 Hz

6.3

5.62

09/07/10

Reset “USER” mode to last frequency

6.3

5.63

11/03/10

Changed Baseline Validity settings

6.3

5.71

03/22/16

Added Driver code for rev B printer & 2X-DGx

6.8

5.72

01/10/18

Enabled Restart printer automatically

6.81b

5.80

11/12/18

Added 1% increments standard

6.81b

4.5

63

Thymatron® System IV Instructions for Use

ADDENDUM II (ELECTRODE PLACEMENT)
4 channel setup with Splitter -> 2 EEG, 1EMG, 1 ECG channel*
to Thymatron System IV ECTto Thymatron System IV EEG/ECG/EMG*Electrode connections for channel 1, 2 EEG, channel 3 EMG, channel 4 ECG recordingThymatron® System IV Instructions for Use

Electrode Splitter

C)

C)

C)

- C•h 1 1 • 2 1 • 3

1+0
ls0o

0
0
0

C)

1• 4
G
nd

to Thymatron System IV EEG/ECG/EMG

Thymatron® System IV Instructions for Use

4-channel setup -> 2 EEG, 1 EMG, 1 ECG channel*

to Thymatron System IV ECTto Thymatron System IV EEG/ECG/EMG*Electrode connections for channel 1 , 2 EEG, channel 3 EMG, channel 4 ECG recordingThymatron® System IV Instructions for Use

3 channel setup -> 1 EEG. 1 EMG, 1 ECG channel*

to Thymatron System IV ECTto Thymatron System IV EEG/ECG/EMG*Electrode connections for channel 1 EEG, channel 3 EMG, channel 4 ECG recording67Thymatron® System IV Instructions for Use

2 channel setup -> 1 EEG, 1EMG channel*

to Thymatron System IV ECTto Thymatron System IV EEG/ECG/EMG*Electrode connections for channel 1 EEG, channel 3 EMG recording68Thymatron® System IV Instructions for Use

1 channel setup -> 1 EEG channel*
to Thymatron System IV ECTto Thymatron System IV EEG/ECG/EMG*Electrode connections for channel 1 EEG recording69

Thymatron® System IV Instructions for Use

ADDENDUM III (INSTRUCTIONS TO PATIENT)
Safety Information

CAUTIONWARNINGFor patients with brain tumor, brain aneurysm, myocardial infarction, coronary insufficiency,
heart failure, or aortic aneurysm medical specialists in Neurology or Cardiology should be
consulted to determine additional precautions needed, if any.

When used as intended, this device provides short-term relief of symptoms. The long-term safety
and effectiveness of ECT treatment has not been demonstrated.

ECT device use may be associated with disorientation, confusion, and memory problems.
WARNING

ECT treatment may be associated with disorientation, confusion and memory loss, including short-term(anterograde) and long-term (autobiographical) memory loss following treatment. Based on the majority ofclinical evidence, these side effects tend to go away within a few days to a few months after the last treatment
with ECT. Although the incidence of permanent cognitive memory loss was not supported by the clinicalliterature, some patients have reported a permanent loss of memories of personal life events (i.e.,
autobiographical memory).
Patients treated with ECT may experience manic symptoms (including euphoria and/or irritability, impulsivity,
racing thoughts, distractibility, grandiosity, increased activity, talkativeness, and decreased need for sleep) or aworsening of the psychiatric symptoms they are being treated for. Depressed patients have committed suicideeven after ECT. Partial decrease in depression may increase risk of suicide.
The physical risks of ECT may include the following (in order of frequency of occurrence): Pain/somatic
discomfort (including headache, muscle soreness, and nausea); Skin burns; Physical trauma (including fractures,contusions, injury from falls, dental and oral injury); Prolonged or delayed onset seizures; Pulmonary
complications (hypoxemia, hypoventilation, aspiration, upper-airway obstruction); Cardiovascular complications(cardiac arrhythmias, heart attack, high or low blood pressure, and stroke); and death.

70Thymatron® System IV Instructions for Use

Clinical testing
Since FDA cleared the Somatics Thymatron ECT device for marketing in 1984, more than 4,300 Thymatrondevices have been used worldwide. Numerous clinical studies have evaluated use of the device in treating severe
depression. Rates of improvement for depressive illness have ranged from negligible to complete recovery, withmost studies reporting substantial improvement. No reports of significant clinical worsening have occurred.
No major adverse events or deaths have been reported in the medical literature naming the Thymatron ECT
device, nor have significant adverse effects been found in the numerous brain imaging and brain biochemical
studies performed to assess the impact of these treatments. The primary adverse effects of ECT with a
Thymatron device have been limited to relatively short-term, reversible disturbances of verbal and nonverbal
memory and general cognition, and most studies actually show improvement in these functions several weeks ormonths after treatment. A single study found impairment in spatial recognition memory continuing one monthafter ECT.

Typical course of treatment:
The Thymatron System IV works while the patient is unconscious from anesthesia, by delivering a brief,
controlled dose of electric current to the scalp in order to induce a brain seizure. This seizure changes chemicals
in the brain called neurotransmitters, which are understood to be effective in treating depression and catatonia.
During the seizure, the device measures the brain, muscle, and heart response to the electrical stimulus. The
seizure usually ends by itself after a minute or two; if not, it may be halted by the clinician via administration ofa known medication. A typical course of treatment is two to three sessions a week for two to three weeks. Somepatients require a longer treatment course.

Potential benefits:
Potential benefits of ECT include relief of the symptoms of catatonia, major depressive disorder, or bipolar
disorder for which the treatment was given.

Alternative treatments:
Alternatives to ECT treatment, depending on the primary diagnosis and the patient's condition, may include
antidepressant drugs, antianxiety drugs, lithium, antipsychotic drugs, behavioral therapy, and/or psychotherapy.

Selected References
Petrides et al (2001), in a National Institutes of Mental Health (NIMH)-supported 4-hospital collaborative study, used a
Thymatron® DGx device to prospectively treat 253 patients with nonpsychotic (n=176) and psychotic (n=77) unipolar
major depression with bilateral ECT at 50% above titrated threshold. Included were patients aged 18 to 85 years withprimary major depression, unipolar type, with or without psychosis, and a baseline Hamilton Depression scale score>20. Excluded were those with a lifetime diagnosis of bipolar illness, schizophrenia, or schizoaffective disorder, a
medical contraindication to ECT, a systemic or neurological condition that might affect mood, failure to respond to atrial of ECT or a lithium-tricyclic antidepressant combination during the present episode, and substance dependence
during the past year. Of the total sample, 56% were female and mean age was 56 years.
A standard ECT protocol was administered with bilateral electrode placement, seizure threshold determination, dosing
at 50% above the titrated seizure threshold, and monitoring seizure efficacy by the duration of EEG-and EMGmonitored seizures. Patients were rated with the 24-item Hamilton depression scale and a neuropsycholical test battery
24-72 hours before the first ECT and after each subsequent ECT before the following treatment. Remission was defined71

Thymatron® System IV Instructions for Use
as 2 consecutive post-ECT-treatment Hamilton Depression Rating Scale scores <11, and a decrease of at least 60% on
this scale from baseline on this scale. Chi-squared analyses were used to evaluate the relationship between unadjusted
remission status and psychosis status. Multivariate logistic regression analyses were used to evaluate the relationshipbetween remission status and psychosis status, adjusted for the effects of confounding or moderator variables; suchanalysis compared the longitudinal profile of total Hamilton scale scores measured 24-72 hours after each ECT for thepsychotic and nonpsychotic depression groups. Most patients achieved scores of ≤10 and >60% reduction in scores forthe first 8 ECTs administered, meeting the criteria for remission. For 217 completers of the acute treatment course, theoverall remission rate was 87%, with a 95% remission rate for psychotic depression and 83% for non-psychotic
depression patients. Side effects among study dropouts included confusion, memory loss, headache, and nausea.
Earlier, the efficacy of ECT had been supported by several controlled trials against antidepressant medications and by
several double-blind, random assignment comparisons of genuine versus sham ECT. Some of these studies are
summarized below.
ECT versus AntidepressantsGreenblatt, Grosser, and Wechsler (1964) included for study all severely depressed patients admitted to 3 statehospitals in Boston. All patients were randomly assigned to receive a course of 9 ECTs (n=28), or imipramine 200-250
mg/day (n=73). At the end of the one-year study period (after which systematic treatment assignment was
discontinued), 76% of the ECT sample was rated markedly improved by a central team of Massachusetts Mental
Health Center physicians, compared with 37% of the imipramine sample (p<.01 by chi-square).
Shepherd M et al. (1965) conducted a collaborative double-blind trial designed by the Clinical Psychiatry Committeeof the British Medical Research Council, in which patients with endogenous depression were randomly assigned toreceive a minimum of 4 weeks of treatment with ECT (n=58), the tricyclic antidepressant imipramine (n=58), or
placebo (n=58). On completion of 4 weeks of treatment physicians’ blind global outcome assessments showed 84% of
the ECT group to be improved, compared with 72% of those on imipramine; 71% of the ECT group showed no or only
slight depressive symptoms, compared with 52% of the imipramine group (chi-squared = 8.75, p<0.0005).
Genuine ECT vs. sham ECT
Brandon et al. (1984) randomly assigned 95 major depressives to courses of either genuine (n=53) or sham (n=42)
bilateral ECT. Eighteen patients failed to complete a full course of treatment, leaving 77 who completed the trial.
Treatment was administered twice per week with a maximum of 8 ECT treatments. On the blindly-administered
Hamilton depressive rating scale, the improvement in the group given real treatment was significantly greater than thatin the group given simulated (sham) treatment both at 2 weeks (p=0.014) and at 4 weeks (p=0.0001). At follow-up at
12 and 28 weeks, there was no difference between the treatment groups. At the end of the 4-week trial consultants
who were blind to the allocation of treatment rated the patients who had received real treatment as having made asignificantly greater improvement than the patients who had received simulated treatment (p<0.0005).
In the Nottingham study, Gregory et al. (1985) randomly assigned 60 depressives to genuine unilateral ECT (n=19),
genuine bilateral ECT (n=21) or sham ECT (n=20) to be administered twice weekly, with approximately 8 ECTs in
total per patient. Results on the blindly-administered Hamilton Depression Rating Scale showed improvements of 31
points in the unilateral ECT group, 28 points in the bilateral ECT group, and 14 points in the sham ECT group.
However, longer-term follow-up did not identify such differences between the groups.
Sartorius et al. (2016) conducted a prospective, MRI-based study of whole brain gray matter volume and voxel-based
cortical thickness in depressed patients with a mean age of 52 years who received a course of titrated right unilateral
ECT with a Thymatron® System IV device. 20 psychiatric inpatients with a Major Depressive Episode (mean
Hamilton Depression Scale score=31.8, mean Mini-Mental State Examination score=27.9) entered the study, of whom72

Thymatron® System IV Instructions for Use
18 received pre- and post-ECT MRIs. Statistically significant whole brain gray matter increases were observed in thetemporal lobe regions of interest, including hippocampus, amygdala, and habenula, as well as an increase of cortical
thickness in temporal lobe and insula. The authors concluded that the data (1) widely excluded white matter loss as
an indirect cause of grey matter growth, and (2) added support to the hypothesis that ECT enables cerebral plasticity,
in contrast to older claims that ECT induces brain damage. No adverse side effects were reported.
Nuninga et al. (2018) compared 48 depressed patients and 19 healthy controls to investigate the effects of bilateral
ECT on cognition in depression in a longitudinal case-controlled study. Included were patients aged >18 years witha diagnosis of unipolar or bipolar depression and an indication for ECT. Excluded were those with past or present
medical condition or brain pathology, prior ECT within 6 months, or present pregnancy/lactation. Patients
underwent various cognitive tests – including of working memory, verbal fluency, visuospatial abilities,
verbal/visual memory and learning, processing speed, inhibition, attention and task-switching, and premorbid IQ –at baseline (n = 43), after ten bitemporal ECT sessions with a Thymatron® System IV (n = 39), and six months after
the tenth ECT session (n = 25). Healthy controls underwent the same cognitive assessment at baseline and after fiveweeks. Clinical response was defined as a 50% reduction in Hamilon depression scle score compared to baseline.
The overall effects of ECT on cognition were assessed via a multivariate repeated measures mixed model; aunivariate mixed model was used to investigate the effects of ECT separately on each cognitive variable. Within thepatient group, transient adverse cognitive side effects were observed for verbal memory and learning, and verbal
fluency. None of the cognitive domains tested showed persisting impairments after six months. Autobiographicalmemory was not assessed. The authors concluded that the data show that although bilateral ECT has short-term
negative cognitive effects that could be explained by a decrease in cognitive performance, a lack of learning effects,
or a combination of both, these negative effects on cognition appear to recede 6 months post-ECT.

73

Thymatron® System IV Instructions for Use

ADDENDUM IV (FLEXDIAL FLOW CHART)

74

Thymatron® System IV Instructions for Use

ADDENDUM V (MOCA TEST)75

Thymatron® System IV Instructions for Use

ADDENDUM VI (INSTRUCTIONS FOR LEGACY METAL OLD TYPESTIMULUS ELECTRODES)CAUTION

In every case, be sure that before giving the electrical stimulus the patient is under anesthesia, thepatient's muscles are fully relaxed, oxygen is being administered, ventilation is supported, a mouth
protector is in place and the impedance is tested.

For bitemporal ECT with two electrode handles, insert one flat metal electrode in each of two handles. Plug thetreatment cable into the receptacles on the handles. Apply conductive electrode gel to the smooth flat surface ofeach electrode. When ready to deliver the electrical stimulus hold each electrode firmly on the intended site.
With a remote treat handle the treat button is on one handle. With no remote treat handle the TREAT button ispressed by a second person familiar with its operation. For bifrontal ECT this procedure is the same except
cupped metal electrodes are used. Likewise with left anterior right temporal placement the right electrode is flatand the left is cupped. For right unilateral ECT the temporal electrode is flat and the electrode near the vertex iscupped.
For bitemporal ECT using a rubber headstrap to hold the metal electrodes: This is usually done before anesthesia
so the patient can assist by holding his head up. Insert one flat electrode in the first hole of the perforated
headstrap and a second flat electrode 8 to 10 inches away, depending on the size of the patient's head. Position
the first electrode about one inch above the mid-point of an imaginary straight line between the external auditory
meatus and the outer canthus of the eye. This is usually on the flat part of the temple.
Then, while holding the first electrode in place, wrap the perforated strap across the forehead and position thesecond electrode over the same spot on the opposite temple. Wrap the strap around the back of the head andinsert another strap perforation onto the first electrode. Adjust strap position so the electrodes are located where
intended. Plug the treatment cable into the receptacles on the metal electrodes.
Then apply electrode gel to the flat surface of each electrode. When you are familiar with this method you may
apply the gel after both electrodes are in the strap before they are placed on the head. For bifrontal ECT thisprocedure is the same except cupped metal electrodes are used. Likewise with left anterior right temporal)
placement the right electrode is flat and the left is cupped.
For right unilateral ECT according to the placement of d'Elia using the perforated rubber headstrap, theheadstrap is used only to hold a flat electrode on the right temple. The procedure for this is similar to bitemporal
ECT except only one electrode is in the strap. Place a cupped electrode in an electrode handle, apply electrodegel, and place it over the scalp just lateral to the vertex. If the patient has hair near the vertex some physicians
clip this hair. Clipping is not necessary if abundant electrode gel is used, but this makes the area slippery andafter treatment the gel should be washed out.

76

Thymatron® System IV Instructions for Use

With all methods, impedance testing is done with both electrodes firmly applied and the treatment cableplugged into the electrode receptacles. The impedance TEST button is then pressed. If the result is above
3000 ohms one or both electrodes are not properly connected to the cable or to the head. Perhaps theelectrodes moved from the intended position, the cable is dislodged or broken, or more conductive gel isneeded.

77

ADDENDUM VII. TABLES OF STIMULUS DETAILS FOR EACH % ENERGY SETTING OF THE
DOSE DIAL
DGX program% Energy
Frequency, hz
Pulse width, ms
Pulse number
Duration, sec

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

6

11

17

22

28

34

39

45

50

56

62

67

73

78

84

90

95

101

106

112

118

123

0.08

0.17

0.27

0.35

0.45

0.73 0.82

0.92

1.38 1.48

1.57

1.67 1.75

1.85

1.95

2.03

Energy, % 23
Frequency, hz 30
Pulse width, ms 1.0
Pulse number 129
Duration, sec 2.13

24

25

26

27

90

95

100

0.55 0.63

28

29

30

35

40

1.02 1.10

4550

1.20 1.28

55

60

65

70

75

80

85

30

30

50

50

50

50

50

50

50

50

50

70

70

70

70

70

70

70

70

70

70

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

162

168

196

224

252

280

308

336

364

392

420

448

476

504

532

560

1.67 1.95

2.23

2.51 2.79

2.59 2.79

2.99

3.19 3.39

3.59

3.79

3.99

20

21

22

134

140

146

151

157

2.22

2.32

1.45

1.50

1.56 1.61

2.19 2.39

LOWEST CHARGE RATE program (0.25) (standard pulsewidth set)
% Energy1Frequency, hz 10
Pulse width, ms 0.25
Pulse number 22
Duration, sec 1.05
Energy, % 23
Frequency, hz 40
Pulse width, ms 0.25
Pulse number 515
Duration, sec 6.43

2

3

4

5

10

10

10

10

0.25

0.25

0.25

0.25

6

7

20

20

0.25 0.25

45

67

90

112

134

2.20

3.30

4.45

5.55

3.33 3.90

24

25

26

27

40

40

50

50

0.25

0.25

0.25

0.25

157

28

29

50

50

0.25 0.25

538

560

582

605

627

6.71

6.99

5.81

6.04

6.26 6.49

650

8

9

20

20

20

0.25 0.25

0.25

179

10

11

12

30

30

0.25 0.25

202

224

246

4.45 5.03

5.58

4.08 4.47

30

35

50

50

60

0.25 0.25

0.25

672

784

6.71 7.83

40

269

13

14

30

30

0.25 0.25
291

314

4.83 5.22

60

16

30

30

30

0.25 0.25

0.25

336

17

18

19

30

30

30

40

40

0.25 0.25

0.25

0.25

0.25

358

381

403

426

448

470

493

5.58 5.95

6.33

6.70 7.08

7.45

5.86

6.15

90

95

100

45

50

70

70

40

50

50

50

60

60

60

70

70

70

0.25 0.25

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

896 1008 1120

616

672

728

784

840

896

952 1008 1064

1120

7.46

7.69 6.71

7.27 7.83

6.99

7.46 7.93

7.19 7.99

55

15

65

70

75

80

85

7.19

7.59

7.99

LOW 0.25 CHARGE RATE program (standard pulsewidth set)
% Energy
Frequency, hz
Pulse width, ms
Pulse number
Duration, sec

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

10

10

10

10

10

20

20

20

20

20

30

30

30

30

30

30

30

30

30

30

40

40

0.25

0.25

0.25

0.25

0.25

0.25 0.25

0.25 0.25

0.25

0.25 0.25

0.25 0.25

0.25 0.25

0.25

0.25 0.25

0.25

0.25

0.25

22

45

67

90

112

134

179

202

224

246

291

336

358

381

403

426

448

470

493

1.05

2.20

3.30

4.45

5.55

3.33 3.90

4.45 5.03

5.58

4.08 4.47

5.58 5.95

6.33

6.70 7.08

7.45

5.86

6.15

Energy, % 23
Frequency, hz 40
Pulse width, ms 0.25
Pulse number 515
Duration, sec 6.43

24

25

26

27

90

95

100

40

40

50

50

0.25

0.25

0.25

0.25

157

28

29

50

50

0.25 0.25

538

560

582

605

627

6.71

6.99

5.81

6.04

6.26 6.49

650

30

35

50

50

60

0.25 0.25

0.25

672

784

6.71 7.83

40

269

45

50

70

70

314

4.83 5.22

80

85

110

120

120

130

140

140

0.25

0.25 0.25

0.25

0.25

0.25

896 1008 1120 1232 1344

1456 1568 1680 1792 1904 2016 2128

2240

7.46

7.28 7.84

0.25 0.25

7.19 7.99

55

60

80

90

0.25 0.25

7.69 7.46

65

70

100

100

0.25 0.25

75

7.63

7.46 7.93

7.75

7.60

8.00

20

21

22

LOW 0.50 CHARGE RATE program% Energy1Frequency, hz 10
Pulse width, ms 0.5
Pulse number 11
Duration, sec 0.50
Energy, % 23
Frequency, hz 20
Pulse width, ms 0.5
Pulse number 258
Duration, sec 6.43

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

10

10

10

10

10

10

10

10

10

20

20

20

20

20

20

20

20

20

20

20

20

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

67

78

90

101

112

123

134

146

157

168

179

190

202

213

224

235

246

4.45 5.00

5.55

3.05 3.33

4.18 4.45

4.73

5.03 5.30

5.58

5.85

6.13

90

95

100

22

34

45

56

1.05

1.65

2.20

2.75

24

25

26

27

3.30 3.85

28

29

30

35

40

45

50

3.63 3.90

55

60

65

70

75

80

85

20

20

30

30

30

30

30

30

30

40

40

40

50

50

50

60

60

60

70

70

70

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

0.5

325

336

392

448

504

560

616

672

728

784

840

896

952 1008 1064

1120

5.58 6.52

7.45

6.29 6.99

7.27 7.83

6.99

7.46 7.93

269

280

291

302

314

6.70

6.98

4.83

5.02

5.22 5.40

7.69 6.71

7.19

7.59

7.99

INTERMITTENT program% Energy
Frequency, hz
Pulse width, ms
Pulse number
Duration, sec

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

30

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

6

11

17

22

28

34

39

45

50

56

62

67

73

78

84

90

95

101

106

112

118

123

0.08

0.27

0.47

0.65

0.85

1.43 1.62

1.82

2.68 2.88

3.07

3.27 3.45

3.65

3.85

4.03

Energy, % 23
Frequency, hz 30
Pulse width, ms 1.0
Pulse number 129
Duration, sec 4.23

24

25

26

27

90

95

100

1.05 1.23

28

29

30

35

2.02 2.20

40

45

50

2.40 2.48

55

60

65

70

75

% Energy
Charge (mC)
Joules at 220Ω

85

30

30

50

50

50

50

50

50

50

50

50

70

70

70

70

70

70

70

70

70

70

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

162

168

196

224

252

280

308

336

364

392

420

448

476

504

532

560

3.27 3.85

4.43

5.01 5.49

5.09 5.49

5.89

6.29 6.69

7.09

7.49

7.89

134

140

146

151

157

4.42

4.62

2.85

3.00

3.06 3.21

4.29 4.69

Charge and Energy at the % Energy Settings of Stimulus Dose Dial
% Energy
Charge (mC)
Joules at 220Ω

80

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

5

10.1

15.1

20.2

25.2

30.2

35.3

40.3

45.4

50.4

55.4

60.4

65.5

70.1

75.6

80.6

85.7

90.7

95.8

101

106

110.9

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0

13.0

14.0

15.0

16.0

17.0

18.0

19.0

20.0

21.0

22.0

100

23

24

25

26

27

28

29

30

35

40

45

50

55

60

65

70

75

80

85

90

95

116

121

126

131

136

141

146

151 176.4

202

227

252

277

302

328

353

378

403

428

454

479

504

23.0

24.0

25.0

25.9

26.9

27.9

28.9

29.9

39.9

44.9

49.9

54.9

59.9

64.9

69.9

74.9

79.8

84.8

89.8

94.8

99.8

34.9