The Optimal Dose of Midazolam for Promoting Sleep in Critically Ill Patients: A Pilot Study

Abstract

Objectives: Many critically ill patients treated in the intensive care unit (ICU) experience sleep disruption. For the sedation of critically ill patients, midazolam is commonly used. This pilot study was undertaken to identify the optimal dose of midazolam for the sound sleep in critically ill patients. Methods: This prospective study was conducted in medical ICU of a tertiary referral hospital. Polysomnography (PSG) recording was performed over 24 h to assess the quantity and quality of sleep in patients who sedated with midazolam. Results: Total nine patients were enrolled. However, the PSGs of three patients could not be interpreted because of artifact or coma at electroencephalography. Therefore, six patients were analyzed. Median total sleep time was 510.0 (IQR: 142.8-865.0) min. The majority of sleep was stage 1 (median 223.5 [IQR 70.8-388.0] min) and stage 2 (median 216.0 [26.0-528.0] min) with scant REM (median 9.5 [2.3-35.3] min) and absent stage 3 (0.0 min) sleep. The wake index and microarousal index were median 14.3 (IQR: 8.0- 25.6) and 16.5 (IQR: 9.9-24.9), respectively. The dose of midazolam showed positive correlation with total sleep time (r = 0.931, P = 0.011). Midasolam dose of 0.05 and 0.01 mg/kg/h showed more than 19 h and <3 h sleep, respectively. Conclusions: The quantity of sleep in critically ill patients was met with continuous infusion of 0.02-0.03 mg/kg/h midazolam. However, the quality of sleep was poor. Further study is required for the promotion of quality of sleep in these patients.