Clinical Analysis of Flumazenil Administration in the Single Emergency Department for Unconscious Patients, Suspected Benzodiazepine Overdose

ABSTRACT

PURPOSE: Flumazenil is an effective benzodiazepine antagonist. However, serious adverse effects, including seizures, cardiac arrhythmias, and even death, have been reported in patients treated with flumazenil. These adverse effects are commonly associated with co-ingested tricyclic antidepressants and benzodiazepine withdrawal. Herein, we examined the safety, effectiveness, and risk of using flumazenil to treat suspected benzodiazepine overdose in the emergency department (ED). METHODS: This is a retrospective observational study of adult patients administered with flumazenil for a known or suspected benzodiazepine overdose in the ED between July 2010 and January 2016. The outcomes included mental status improvement, incidence of seizures, and intubation rate after flumazenil administration. RESULTS: Seventy-six patients were included in the analysis. Thirty-eight (50%) patients experienced clinically significant mental status improvement. One patient had a seizure (1.3%), despite 17 reported proconvulsant coingestants. No patient required endotracheal intubation, and no patient had arrhythmias after flumazenil administration. Flumazenil was given intravenously bolus in all cases, and the average dose was 0.44mg. There were no significant changes in the vital signs after flumazenil administration. CONCLUSION: Flumazenil was effective and associated with a low frequency of seizure. However, patients with contraindications may develop seizures. The benefits with respect to risk of adverse effects should be considered carefully in all patients.