Clinical trial NCT03140982: Is Anesthetic Loss of Consciousness a Top Down or Bottom up Phenomenon. What Does the Neurologic Examination Say?.
Official title: Is Anesthetic Loss of Consciousness a Cortical or Brainstem Phenomenon? What Does the Neurological Examination Say?
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Anesthesia; Functional
Keywords: propofol
pharmacology
anesthesic induction
drug titration
Lead sponsor: Universidad del Desarrollo
Sponsor class: OTHER
First posted: 2017-05-04
Enrollment: 16
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: comparison of the neurologic behavior between two group, a fast and a slow anesthesia induction
Primary purpose: DIAGNOSTIC

Brief summary: Using very slow or fast propofol intravenous injection, monitored using standard American Society of Anesthesiology (ASA) standard and SEDLine EEG (Med Tech), the patient was evaluate by a neurologist every 30 sec using the FOUR coma scale.

Detailed description: Clinical experimental randomized study, approved by the Ethic Committee, with informed consent, included ASA I- II adults, without neurological illness and normal physical exam.

The patient randomized in two groups, rapid induction (GR) with propofol in target controlled infusion (TCI) effect site mode using the phamacokinetic (PK) model from Marsh ke0 1,21 min-1 using a calculated target of 5.4 ug/ml (loss of counsciousness EC95) and slow induction (GL) 10 mg/kg/h with calculated effect site concentrations (CeCALC) same PK model.

The same neurologist, blind to the correspondent group, evaluated all the patients every 30 sec using the coma FOUR scale until loss of counsciousness (LOC), defined as a FOUR (E0 no eyes opening response and /or M0 no motor response). At LOC the existance of brainstem reflex was evaluated (B no pupil and corneal reflex), respiratory pattern (R apnoea), CeCALC and patient state index (PSI) SEDline™ was recorded during all the examination.

After LOC in both groups we maintain in GR the initial target (5.3 ug/ml) and the LOC CeCALC during 10 min without intervention, except respiratory support if it was required.

Frontal EEG 4 channel and spectrogram from SEDline monitor was extracted for each case and posterior analysis.

Fisher exact test was used to describe primary outcome and difference between B and R for each group. The difference in time to reach LOC LOC, Ce and PSI was analysed with T- Student.

Eligibility criteria: Inclusion Criteria: ASA 1-2 patients programmed for elective surgery, normal neurologic examination -

Exclusion Criteria: neurologic illness, receiving drugs that affect Central Nervous System during the last 48 hours

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Primary outcomes:
measure: loss of consciousness a cortical or brainsteam phenomenon
timeFrame: 1 year
Secondary outcomes:
measure: evaluation of the alfa band behavior after fast and slow inductions
timeFrame: 1 year
Other outcomes:
Locations:
city: Santiago
country: Chile
facility: Clinica Alemana de Santiago
state: Region Metropolitana
Study officials:
affiliation: Clinica Alemana Comité Cientifico
name: Pablo Lavados, MD
role: STUDY_CHAIR
References:
citation: Brown EN, Lydic R, Schiff ND. General anesthesia, sleep, and coma. N Engl J Med. 2010 Dec 30;363(27):2638-50. doi: 10.1056/NEJMra0808281. No abstract available.
citation: Mashour GA. Top-down mechanisms of anesthetic-induced unconsciousness. Front Syst Neurosci. 2014 Jun 23;8:115. doi: 10.3389/fnsys.2014.00115. eCollection 2014.
citation: Wijdicks EF, Bamlet WR, Maramattom BV, Manno EM, McClelland RL. Validation of a new coma scale: The FOUR score. Ann Neurol. 2005 Oct;58(4):585-93. doi: 10.1002/ana.20611.