Evaluation of the Compuflo Epidural Instrument for Thoracic Epidural Space Identification
Phase: NA
Conditions: Anesthesia, Thoracic
Sponsor: University of Miami

Protocol Title: 
 
Evaluation of the Compuflo Epidural Instrument for Thoracic Epidural Space 
Identification 
 
NCT Number: NCT03376256 
 
Document Date: February 20, 2018  
 
 
Objectives: 
 
Purpose of this pilot study is to evaluate whether this injection pump technology, 
which is FDA approved for lumbar epidural anesthesia, is also capable of identifying 
the thoracic epidural space through measurement of pressure levels.  While this 
device is approved by the FDA for use in the procedure of the lumbar epidural, it is 
not actually used to perform the epidural procedure but rather to measure the 
epidural pressure. This study will likewise measure the epidural pressure. 
 
 
Background: 
 
A successful and safe performance of epidural anesthesia/analgesia in the 
perioperative setting relies on correct identification of the epidural space (ES) by the 
operator. Multiple methods for objective and more or less simple identification of the 
ES have been proposed such as waveform analysis (1), nerve stimulation (2), fiber 
optical or ultrasound guidance (3,4), and acoustic signal assistance (5). 
However, none of these suggested techniques is currently standard of care and most 
anesthesiologists and/or pain physicians still utilize the subjective manual feeling of 
a loss of resistance (LOR). 

Consequently, reported epidural failure rates using LOR for ES identification vary 
greatly and can range for instance for labor epidural analgesia from 1.5% up to 23%, 
if a standardized definition of epidural failure is applied (6,7).  Failure rates for 
epidural analgesia for postoperative pain management after major surgery are even 
higher and can reach up to 27% for lumbar and 32% for thoracic epidurals (8).  
Previously, the now FDA approved Compuflo Epidural Instrument has been 
demonstrated to successfully and safely identify the lumbar epidural space. This 
technology allows for real-time pressure readings at the epidural needle tip, which 
are displayed in digital and graphical fashion. 
This study is designed to evaluate this technology for ES identification when 
performing thoracic epidural anesthesia. 
 
1) Leurcharusmee P, Arnuntasupakul V, Chora De La Garza D, Vijitpavan A, Ah-Kye   
     S, Saelao A, Tiyaprasertkul W, Finlayson RJ, Tran DQ.  Reliability of Waveform   
    Analysis as an Adjunct to Loss of Resistance for Thoracic Epidural Blocks. 
    Reg Anesth Pain Med. 2015; 40: 694-7 
2) Tsui BC, Gupta S, Finucane B. Confirmation of epidural catheter placement using   
    nerve stimulation. Can J Anaesth. 1998; 45: 640-4 
3) Kuo WC, Kao MC, Chang KY, Teng WN, Tsou MY, Chang Y, Ting CK. Fiber-needle   
    swept-source optical coherence tomography system for the identification of the  
    epidural space in piglets. Anesthesiology. 2015; 122: 585-94 
4) Vallejo MC, Phelps AL, Singh S, Orebaugh SL, Sah N. Ultrasound decreases the   
    failed labor epidural rate in resident trainees. Int J Obstet Anesth.  
   2010;19: 373-8 
5) Lechner TJ, van Wijk MG, Maas AJ. Clinical results with a new acoustic device to  
     identify the epidural space. Anaesthesia. 2002; 57: 768-72 
6) Crawford JS. The second thousand epidural blocks in an obstetric hospital   
     practice. Br J Anaesth 1972; 44: 1277-1286 
7) Thangamuthu A, Russell IF, Purva M. Epidural failure rate using a standardised    

    definition. Int J Obstet Anesth. 2013; 22: 310-5 
8) Ready LB. Acute Pain: lessons learned from 25,000 patients. Reg Anesth Pain Med  
    1999; 24: 499-505 
 
 
 
 
 
 
 
Inclusion criteria: 
Patients aged between 18 and 80 years inclusive. Body mass index (BMI) between 
18.5 and 40 inclusive. Patients scheduled to undergo thoracic epidural anesthesia as 
part of the planned anesthetic management.  
 
Exclusion criteria: 
Patients younger than 18 years of age or older than 80 years of age. Patients with a 
BMI less than 18.5 or greater than 40. Patients with contraindications for thoracic 
epidural anesthesia. Patients with an allergy to local anesthetics. Patients with 
preexisting nerve damage.  Patients who are unable to provide informed consent.  
Individuals who are not yet adults, pregnant women, and prisoners will not be 
included. 
Procedures Involved:  

After IRB approval and patient informed consent, a total of 20 patients scheduled to 
receive thoracic epidural needle placement, as part of their scheduled medical 
management, will be enrolled in this prospective observational trial (NTC…) at the 
University of Miami Hospital and Jackson Memorial Hospital 
The study will be conducted in 2 phases. In Phase A, 10 patients will have their ES 
identified with the traditional LOR technique and the Compuflo Epidural Instrument 
will be solely used to obtain pressure readings once the ES has been reached. In Phase 
B 10 patients will have their ES identified with the Compuflo epidural Instrument and 
the LOR technique will be used for confirmation.  
Phase A – Thoracic Epidural Space Identification with traditional LOR: 
Patients will receive thoracic epidural anesthesia in the following fashion: 
After attaching American Society of Anesthesiologists standard monitors, patients 
will be placed in a sitting position. Following disinfection and preparation in the usual 
fashion, an epidural Tuohy needle will be introduced at a thoracic level o to a depth 
of approximately 3cm. The epidural Tuohy needle will then be connected to a 3-way 
stopcock with a loss of resistance syringe filled with normal saline connected to the 
in-line port and the Compuflo Epidural Instrument connected to the side-port. The 
stopcock will be turned “Open” to the LOR syringe and “Close” to the Compuflo 
Epidural Instrument. The operator will then advance the epidural Tuohy needle until 
a loss of resistance is perceived.  The stopcock will then be turned “Open” to the 
Compuflo Epidural Instrument and “Close” to the LOR syringe. The Compuflo 
Epidural Instrument will be started at an infusion rate of 0.050ml/sec of normal 

saline for 30 seconds. The pressure readings will be graphically and digitally 
recorded.  
The Compuflo Epidural Instrument will then be stopped and the stopcock will be 
disconnected from the Tuohy needle. After disconnection of the epidural Tuohy 
needle, an epidural catheter will be advanced at the discretion of the operator. After 
removal of the epidural needle and securing of the epidural catheter, a 3 mL epidural 
test dose consisting of lidocaine (15 mg/mL) with epinephrine (5 mcg/mL) will be 
given to rule out intrathecal or intravascular catheter position. Epidural anesthesia 
will then be established at the discretion of the operator by dosing the epidural 
catheter with a local anesthetic of their choice and a volume of their choice. Fifteen to 
thirty minutes after dosing the epidural catheter a blinded investigator will assess the 
patient for sensory and motor blockade.  Successful performance of epidural 
anesthesia will be defined as a loss of sensation to cold in at least one dermatome, 
either unilateral or bilateral. If an epidural catheter cannot be advanced into the 
epidural space, the epidural Tuohy needle will be withdrawn to a depth of 3cm or  
completely removed and inserted at a new puncture site and a new attempt of 
epidural Tuohy needle insertion and identification of the epidural space with the loss 
of resistance technique will begin. After a maximum of 3 failed attempts, epidural 
space identification will be considered unsuccessful 
 
 
Phase B – Thoracic Epidural Space Identification with the Compuflo Epidural 
Instrument: 
Patients will receive thoracic epidural anesthesia in the following fashion: 

After attaching American Society of Anesthesiologists standard monitors, patients 
will be placed in a sitting position. Following disinfection and preparation in the usual 
fashion, an epidural Tuohy needle will be introduced at a thoracic level o to a depth 
of approximately 3cm. The epidural Tuohy needle will then be connected to a 3-way 
stopcock with a loss of resistance syringe filled with normal saline connected to the 
in-line port and the Compuflo Epidural Instrument connected to the side-port. The 
stopcock will be turned “Close” to the LOR syringe and “Open” to the Compuflo 
Epidural Instrument. The Compuflo Epidural Instrument is started and set to infuse 
normal saline at a rate of 0.050ml/sec with a pressure limit of 100mmHg. The 
operator will then slowly advance the epidural Tuohy needle until the Compuflo 
Epidural Instrument indicates that the ES has been reached. This is achieved by 
observation of a drop of pressure of at least 50mmHg sustained for at least 5 seconds 
(“low pressure plateau”).  The Compuflo Epidural Instrument will then be stopped 
and the stopcock will be turned “Close” to the Compuflo Epidural Instrument and 
“Open” to the LOR syringe. Once the operator has confirmed correct ES identification 
with the LOR syringe, the stopcock will be disconnected from the Tuohy needle. 
After disconnection of the epidural Tuohy needle, an epidural catheter will be 
advanced at the discretion of the operator. After removal of the epidural needle and 
securing of the epidural catheter, a 3 mL epidural test dose consisting of lidocaine (15 
mg/mL) with epinephrine (5 mcg/mL) will be given to rule-out intrathecal or 
intravascular catheter position. Epidural anesthesia will then be established at the 
discretion of the operator by dosing the epidural catheter with a local anesthetic of 
their choice and a volume of their choice. Fifteen to thirty minutes after dosing the 

epidural catheter a blinded investigator will assess the patient for sensory and motor 
blockade.  Successful performance of epidural anesthesia will be defined as a loss of 
sensation to cold in at least one dermatome, either unilateral or bilateral. If an 
epidural catheter cannot be advanced into the epidural space, the epidural Tuohy 
needle will be withdrawn to a depth of 3cm or completely removed and inserted at a 
new puncture site and a new attempt of epidural Tuohy needle insertion and 
identification of the epidural space with the loss of resistance technique will begin. 
After a maximum of 3 failed attempts, epidural space identification will be considered 
unsuccessful. 
 
Follow up: 
 
Patients will be evaluated in a timeframe of 12h-24h after epidural catheter removal 
for potential complications. A sensory and motor exam will be performed. Patients 
will also be evaluated for any symptom of post-spinal-puncture headache. Patients 
who did not receive epidural anesthesia due to inability to identify the epidural space 
will be evaluated in the same fashion in a timeframe of 12-24h after attempted 
epidural anesthesia. 
 
Data collection: 
Data will be collected on case report forms. Demographic data of each patient 
(weight, height, age, gender) will be recorded at the beginning of each case.  
Pressure readings from the Compuflo Epidural Instrument will be recorded once the 
epidural space is reached in Phase 1 of the study, and throughout the procedure in 
Phase 2. Success rate of epidural anesthesia and complications will be recorded.  

Data will be stored in individual study folders and locked in a Division of Regional 
Anesthesia faculty office. 
 
Data management  
Demographical data and pressure readings will be analyzed by calculating a mean 
and standard deviation. Success rates and incidence of complications will be recorded 
in percentages and a median including 25th to 75th percentile range will be calculated. 
 
Risks/ Benefits 
In Phase 1 of the study, there will be no personal direct benefit and minimal risk for 
harm since the Compuflo Epidural Instrument will be solely used for the purpose of 
measuring pressures while the actual performance of thoracic epidural anesthesia 
will be with the traditional LOR method.  
In Phase 2 of the study, the patient may directly benefit from the more objective 
identification method of the epidural space with the Compuflo Epidural Instrument.  
A potential risk is electrical failure of the computerized injection pump; in such case, 
the operator will revert back to the traditional LOR technique. 
 
Setting: 
Research consents will be obtained in the operating room holding area of the 
University of Miami Hospital or Jackson Memorial Hospital, as applicable, for 
patients admitted the day of the procedure. In hospital patients will be consented 

the night prior to the procedure in their admitted locations. This study will  take 
place at University of Miami Hospital or Jackson Memorial Hospital.  
 
Resources available: 
Dr. Ralf E. Gebhard is a Professor of Clinical Anesthesiology and Director of the 
Division of Acute Pain Medicine and Regional Anesthesia in the Department of 
Anesthesiology, Perioperative Medicine and Pain Management at the University of 
Miami Miller School of Medicine.  He has conducted substantial previous research as 
the principal investigator in multiple clinical trials in the area of acute pain and 
regional anesthesia. Dr. Gebhard will be responsible for overseeing the recruitment, 
consent, collection and storage of data as well as performing the measurements 
described in the procedure section. 
Dr. Robyn Weisman is an Assistant Professor in Clinical Anesthesiology and in the 
Division of Acute Pain Medicine and Regional Anesthesia. She has participated in 
investigator-initiated research and authored manuscripts in anesthesiology 
previously and is well versed in research compliance. 
The study coordinators are experienced in conducting clinical research for clinical 
trials and investigator-initiated studies. They will assist the investigators in study-
related activities. 
Patient Recruitment Methods: 
Potential subjects will be identified by the study team based on the scheduled procedures 
to be done by the Regional Anesthesia team. Patients on the schedule will be pre-
screened using available medical data for exclusion criteria. If patients do not meet any of 

the exclusion criteria they will be visited by the Principal Investigator, Sub-investigator 
and/or Study coordinators on the morning of surgery or the night before depending on 
their admission status. If the subject is currently an inpatient at the hospital, the medical 
team taking care of the patient will be approached by the study team to get permission to 
approach the subject. Study details, risks, benefits and alternatives will be discussed with 
each potential subject. If the patient shows interest into the study, the PI will notify 
research personnel of potential participant to start the process of consent. Study 
information and informed consent document (attached) will be provided to each subject. 
If the patient agrees to the study a copy of the signed consent will be provided to the 
patient and one placed in the patient medical chart. The original document will be placed 
in the study specific subject folder.  
 
 
Local number of subjects: 
A total of 20 patients will be expected to be enrolled into this pilot study. 
 
Confidentiality: 
Data will be recorded on study sheets locked in a Division of Regional Anesthesia 
faculty office in a locked filing cabinet for the period of one year. Additionally, data 
will be stored on a password protected University of Miami computer in the 
Department of Anesthesiology in Suite 3075, 1400 NW 12th Avenue, Miami, Florida, 
33136. Only study personnel listed on the IRB protocol will have access to the data. 
All study records and documents, will be retaind for studies that are subject to both 

FDA and HIPAA regulations: According to HIPAA regulations will be retained for a 
minimum of six years following study closure. Our research department will retain 
all research data until the later of these dates. The data will be destroyed after this 
time in accordance with university policies. 
 
Consent process: 
Written informed consent will be obtained for each subject in English-speaking 
subjects only. Subjects who do not speak English will not be enrolled. Research 
consent will be obtained in the operating room holding area of University of Miami 
Hospital for patients admitted the day of the procedure. In hospital patients will be 
consented the night prior to the procedure in their admitted locations. 
Patient's identity and age will be verified prior to obtaining informed consent, as 
well as their understanding of risks and benefits and possible alternatives available 
explained before any informed consent signature from those patients willing to 
participate. The PI(s) with each study participant will:  
• Ensure each patient is given full and adequate oral and written information about 
the nature, purpose, possible risk, and benefit of the study. 
• Ensure each patient is notified that they are free to discontinue from the study at 
any time. 
• Ensure that each patient is given the opportunity to ask questions and allowed 
time to consider the information provided. 
• Ensure each patient provides signed and dated ICF before conducting any 

procedure specifically for the study. 
• Ensure the original, signed ICF(s) is/are stored in the investigator’s Study File. 
• Ensure a copy of the signed and dated ICF is given to the patient for future 
reference of the study. 
• Ensure that any incentives for patients who participate in the study as well as any 
provisions for patients harmed as a consequence of study participation are 
described in the ICF that is approved by an IEC/IRB. 
All potential subjects will be given ample time to review the consent form and discuss 
any questions and concerns with research personnel or study doctor, and will be 
provided with a copy of the signed ICF. Consent will be documented with a dated 
signature on the consent form from both the patient and the study personnel 
conducting the consent discussion.