Dexmedetomidine in the emergency department: assessing safety and effectiveness in difficult-to-sedate acute behavioural disturbance

Objectives: To investigate the safety and effectiveness of dexmedetomidine for sedating patients in whom previous attempts at sedation in the emergency department have failed. Methods: A study was carried out on dexmedetomidine for sedation of patients with acute behavioural disturbance for whom at least two previous attempts at sedation with other drugs had failed. Either a loading dose of dexmedetomidine was administered or a loading dose then an infusion. Administration was titrated to the sedative effect and vital signs. The sedation assessment tool was used to assess effectiveness, and adverse effects were recorded. Effective sedation was defined as a fall in the sedation assessment tool by two levels or more for an hour or more. Results: A total of 13 patients were given dexmedetomidine. Five of the 13 had a loading dose only. Of these five, successful sedation was achieved in two, and the other three were only briefly sedated during the loading dose. One patient had hypotension. Eight patients received an infusion after the loading dose. Three were successfully sedated, but one developed hypotension. Four patients required a decrease in the infusion rate for hypotension, and in three of these the rate decrease compromised the sedation and one of these required intubation for sedation. The final patient had persistent acute behavioural disturbance, which required intubation for management. Five of the eight patients developed hypotension, and, of the five, one had bradycardia and one went into atrial fibrillation. Conclusion: Intravenous dexmedetomidine for difficult-to-sedate patients with acute behavioural disturbance is not safe in the emergency department setting.