# Recovery Time Following Continuous Midazolam Infusion During Dental Implant Surgery: A Prospective Observational Study

## TL;DR

This study found that patients sedated with midazolam during dental implant surgery can be discharged within 90-110 minutes after starting the drug.

## Contribution

The study provides specific recovery time data for midazolam sedation in dental implant surgery using bispectral index monitoring.

## Key findings

- Patients could be discharged within 90-110 minutes after midazolam administration.
- Awakening occurred when bispectral index reached ≥90, with discharge following a postanesthetic score of ≥9.
- Sedation duration of 50 minutes allowed for timely patient discharge.

## Abstract

Introduction: This study measured recovery time following sedation with a continuous midazolam infusion during implant surgery.

Methods: In this prospective observational study, we evaluated American Society of Anesthesiologists (ASA) I or II patients who underwent sedation with continuous midazolam infusion during implant surgery. The recovery time was measured at Nippon Dental University Hospital from December 2019 to July 2021. Patients under 18 years old with a history of drug allergies, obesity (body mass index of 26 kg/m2 or more), or regular use of antipsychotic, psychotropic, or hypnotic substances were excluded from the study. Midazolam was administered as a bolus dose of 0.05 mg/kg, followed by a continuous infusion to maintain a bispectral index (BIS) of 70-80. Midazolam was discontinued at the end of the procedure, and the awakening time was defined as that when the BIS was ≥90. After transfer to the recovery room, the patient’s condition was assessed using the postanesthetic discharge scoring system (PADSS) and then reassessed every 20 minutes. When the score reached ≥9, the patient was allowed to return home. The elapsed time from initiation of midazolam to when the PADSS score exceeded 9 was 90-110 minutes. Covariate variables were collected, including age (years), gender (male or female), weight (kg), local anesthetics (mL), surgical and sedation time (minutes), and induction and total dose of midazolam (mg).

Results: Forty-six patients participated in the study. Patients had a mean age of 59.4 (±12.1) years, a male-to-female ratio of 20:26, and a mean weight of 59.5 (±11.6) kg. Patients could be discharged within approximately 90-110 minutes of the start of midazolam administration.

Conclusion: If the 50 minutes of conscious sedation with midazolam were properly controlled, patients could be discharged within approximately 90-110 minutes of the start of midazolam administration. This means they can return home within 40-60 minutes after awakening.