The Effect of Fixed Dose of Flumazenil on Recovery after Sedative Endoscopy by Midazolam

Kwon, Kye Hyoung; Park, Young Sook; Kim, Tae Hun; Jo, Yun Ju; Song, Moon Hee; Kim, Chung Hyeon; Kim, Seong Hwan

Abstract

BACKGROUND/AIMS: Midazolam is widely used as a form of conscious sedation during endoscopy because of its rapid onset and safety. However, its relatively long half-life and paradoxical reactions are still a concern for doctors and patients. Flumazenil is a competitive benzodiazepine antagonist that acts to reverse the sedative and hypnotic effects of midazolam but its role and adequate dose have not been fully documented. This study evaluated the effect of a fixed dose of flumazenil on the recovery from sedative endoscopy by midazolam.
METHODS
First study: 100 patients who received 0.05 mg/kg midazolam for conscious sedation were randomized into two groups: intravenous 0.25 mg flumazenil and a placebo. All patients were assessed using OAA/S (Observers Assessment of Alertness/Sedation Scale) scale (responsiveness, speech, facial expression and ptosis of eyelid) before the endoscopy, immediately after the procedure and every 5 minutes thereafter. The recovery time was defined as the time at which the OAA/S scale reached the pre-endoscopy level. Second study: In 40 patients, the OAA/S scale was assessed only after full recovery without any exogenous stimuli. The total dose of midazolam and the procedure time were assessed.
RESULTS
The flumazenil group demonstrated a significantly shorter recovery time than the placebo group (p<0.0001). These results were not affected by age, gender, total midazolam dose and procedure time. There was a larger difference in the recovery time between the two groups in the second study than in the first.
CONCLUSIONS
A fixed low dose flumazenil significantly reduced the recovery time after sedative endoscopy by midazolam. Flumazenil will be helpful for the early return to daily activities and for preventing post sedative complication.