Low-dose dexmedetomidine administered at night to critically ill adults reduced the incidence of delirium during intensive care unit (ICU) stays and patient-reported sleep quality remained unchanged, according to a study published in the American Journal of Respiratory and Critical Care Medicine.
Delirium in critically ill adults is independently associated with longer hospital stay and higher costs and may affect cognitive recovery. Although dexmedetomidine is associated with a lower incidence of delirium than midazolam and propofol in the ICU, it was not known whether dexmedetomidine simply caused less delirium or if it reduced delirium incidence.
Yoanna Skrobik, MD, FRCP, MSc, of the Department of Medicine at McGill University in Montreal, Quebec, Canada, and colleagues conducted a double-blind, placebo-controlled trial that randomly assigned 100 critically ill adults without delirium who were receiving sedatives to receive nocturnal intravenous dexmedetomidine or placebo until ICU discharge. All sedatives were halved during study infusions, but opioid medications were unchanged.
The investigators assessed delirium using the Intensive Care Delirium Screening Checklist every 12 hours throughout the time the patients were in the ICU and evaluated sleep each morning using the Leeds Sleep Evaluation Questionnaire.
A greater percentage of patients who received dexmedetomidine (80%) remained delirium free during the ICU stay than patients who received placebo (54%; P =.006). However, the average Leeds Sleep Evaluation Questionnaire score was similar in the 2 groups of patients, and the incidence of hypotension, bradycardia, or both did not differ significantly between the 2 groups.
The study has several limitations. First, the authors noted that only 26% of screened patients were enrolled, which may have compromised external validity. In addition, the study may have been too small to detect differences in the duration of mechanical ventilation and length of ICU stay. Furthermore, a difference in sleep-related outcomes may have become evident if other methods to evaluate sleep quality, such as polysomnography, had been used.
The researchers called for further evaluation of the role for nocturnal dexmedetomidine in patients admitted to the ICU with delirium.
Skrobik Y, Duprey MS, Hill NS, Devlin JW. Low-dose nocturnal dexmedetomidine prevents ICU delirium: a randomized, placebo-controlled trial [published online March 2, 2018]. Am J Respir Crit Care Med. doi:10.1164/rccm.201710-1995OC