Predictors of increased flumazenil requirements in emergency settings: A multicenter retrospective study.

INTRODUCTION

Flumazenil is commonly used as an antidote for benzodiazepine overdose. However, information regarding dosing practices in hospital emergency departments remains limited. This study aimed to identify the clinical factors associated with the administration of higher flumazenil doses in the emergency department setting.

METHODS

This was a retrospective observational study. Adult patients treated with flumazenil in eighteen Spanish emergency departments during 2023 were included. Patient comorbidities, drugs and toxics involved in the intoxication, and the doses of flumazenil administered were recorded. A logistic regression model was used to assess factors associated with increased dosing (>0.5 mg).

RESULTS

A total of 798 patients were included [51.4 years (SD: 21.4), 457 (57.3%) female]. Benzodiazepine intoxication was confirmed in 513 cases (64.3%). In addition, 45 (8.9%) patients presented concomitant intoxication with opioids, and 117 patients (22.8%) had concurrent alcohol use. The median dose of flumazenil was 0.75 mg (range: 0.125-23.1). In 338 patients (42.4%), flumazenil was delivered via continuous infusion. In the multivariate model, a significant association with higher dose was found with age younger than 65 years [OR: 2.12 (1.50-3.00)] and chronic benzodiazepine use [OR: 1.69 (1.22-2.35)].

CONCLUSIONS

Flumazenil dosing in emergency department is highly variable. Increased dose requirements were observed in younger patients and chronic benzodiazepine use.