Standard- versus High-Dose Dexmedetomidine for Sedation in the Intensive Care Unit.

Dexmedetomidine is a commonly used sedative in the intensive care unit (ICU), however the use of higher, off label dosing has yet to be elucidated. A dose limitation protocol was implemented at our institution allowing for comparison of dexmedetomidine doses. The purpose of this study is to evaluate time spent within goal Richmond Agitation Sedation Scale (RASS) range with standard-dosing of dexmedetomidine ≤1 mcg/kg/hour (SD group) compared to high-dose >1 mcg/kg/hour (HD group). Secondary outcomes included days requiring mechanical ventilation, concomitant sedation, and incidence of hypotension or bradycardia. This retrospective chart review of adult ICU patients at a single academic medical center included patients who required at least 24 hours of mechanical ventilation and received dexmedetomidine monotherapy for at least 4 hours. Patients were excluded for intubations at an outside hospital, continuous neuromuscular blocking infusions, or Glasgow Coma Score ≤4. A total of 144 patients met inclusion criteria (n = 121 SD group and n = 23 HD group). The SD group spent a greater time within goal RASS range compared to the HD group (84.5% [IQR 47-100] vs 45.5% [IQR 30.1-85.4],  = .013). The SD group also had shorter durations of both dexmedetomidine infusion and mechanical ventilation, and required less concomitant sedation. There was no difference in hypotension or bradycardia. This study further adds to the literature that administration of high-dose dexmedetomidine does not appear to confer additional benefit over standard doses for ICU patients requiring mechanical ventilation. Application of this data may support lower institutional maximum doses.