Effectiveness of Quetiapine As a Sedative Adjunct in Mechanically Ventilated Adults Without Delirium

Background: Quetiapine is an atypical antipsychotic that is commonly used in the Intensive Care Unit (ICU). The utility of quetiapine as a sedative adjunct has not yet been evaluated, but has been described previously in studies evaluating quetiapine for delirium or delirium prophylaxis. Objective: To determine if adjunctive use of quetiapine reduces sedative dosage requirements among mechanically ventilated adults without delirium. Methods: This retrospective intrapatient comparator study included all mechanically ventilated adults admitted to a medical ICU who received quetiapine between July 1, 2013, and July 1, 2018. The primary outcome was the change in sedative dosage requirements over 24 hours following quetiapine initiation. Secondary outcomes included change in sedative dosage requirements 48 hours postquetiapine initiation, opioid dosage requirements 24 hours postquetiapine initiation, percent time at goal for both pain and sedation scores, depth of sedation, and QTc. Results: A total of 57 patients were included in the study cohort. There was no significant difference in 24-hour cumulative doses of propofol ( P = 0.10), dexmedetomidine ( P = 0.14), or benzodiazepines ( P = 0.14). During the 48-hour treatment period, there was a significant increase in dexmedetomidine requirements ( P = 0.03). There were no differences in 24-hour opioid dosage requirements, percent time at goal pain or sedation scores, depth of sedation, or QTc following quetiapine initiation. Conclusion and Relevance: Adjunctive use of quetiapine was not associated with a significant reduction in sedative dosage requirements 24 or 48 hours following initiation among mechanically ventilated adults without delirium.