Effect of Flumazenil on Recovery From General Anesthesia With Isoflurane

Effect of Flumazenil on Recovery From General Anesthesia With Isoflurane: a Randomized Controlled Trial

Background and objectives: The inhalational anesthetic isoflurane is widely used in general anesthetics. Its mechanism of action involves interaction with the receptor of gamma-amino butyric acid (GABA), which is also the binding site for benzodiazepines. Flumazenil, benzodiazepine antagonist, reverses the effects of these drugs in GABA receptors and could therefore also reverse the effect of isoflurane. In anesthesia practice, extubation and early anesthetic recovery reduce morbidity and incidence of complications. The objective of this trial is to determine whether the use of flumazenil may contribute to faster recovery from anesthesia. Methods: 40 patients scheduled to undergo general anesthesia with isoflurane were enrolled in this prospective, double-blind, randomized trial. Patients were randomized to receive, at the end of anesthesia, flumazenil or placebo as allocated into two groups. The anesthetic technique was standardized. The groups were compared concerning values of Cerebral State Index (CSI), heart rate, blood pressure and oxygen saturation from the application of flumazenil or placebo until 30 minutes after injection. Data regarding time to extubation, time to reach ten points in the Aldrete-Kroulic score (AK = 10) and Vigilance score (VS = 10) was also collected. ANOVA test was applied to analyze the results, considering p <0.05.

Study Overview

• Status: Completed
• Conditions: Adverse Effect of Other General Anesthetics
• Intervention / Treatment: Drug: saline; Drug: Flumazenil

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • São Paulo, Brazil, 05508-000
    • Hospital Universitário USP

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• patients scheduled to surgeries with general anesthesia,
• healthy or with minor diseases completely controlled by regular use of medications (ASA I or II according to the classification of physical state by the American Society of Anesthesiologists).

Exclusion Criteria:

• patients with past of chronic use of benzodiazepines and/or illicit drugs,
• seizures or panic disorder.

Study Plan

How is the study designed?

Design Details

• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: DOUBLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: saline; patients received 20 ml of saline during 1 minute, after end of surgery.	Drug: saline
Active Comparator: flumazenil; patients received 1 mg of flumazenil, after end of surgery	Drug: Flumazenil

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Time of recovery from a general anesthesia isoflurane based	up to 8 hours

Collaborators and Investigators

• Sponsor: University of Sao Paulo

Study record dates

Study Major Dates

• Study Start: January 1, 2011
• Primary Completion (Actual): September 1, 2012
• Study Completion (Actual): September 1, 2012

Study Registration Dates

• First Submitted: June 1, 2014
• First Submitted That Met QC Criteria: June 5, 2014
• First Posted (Estimate): June 6, 2014

Study Record Updates

• Last Update Posted (Estimate): June 6, 2014
• Last Update Submitted That Met QC Criteria: June 5, 2014
• Last Verified: June 1, 2014

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Protective Agents; GABA Modulators; GABA Agents; Antidotes; Flumazenil
• Other Study ID Numbers: 984/10