Adverse Hemodynamic Effects of Dexmedetomidine in Critically Ill Elderly Adults

Background: Dexmedetomidine is a currently recommended first-line sedative agent for critically ill patients requiring mechanical ventilation. Recent trials demonstrated no difference in clinical outcomes between patients treated with dexmedetomidine vs usual care, but significantly more hemodynamic adverse effects in the dexmedetomidine group. One subgroup analysis suggested a 90-day mortality benefit in elderly patients, but no distinction was made between groups regarding age when reporting adverse effects. Given potential decreased baroreceptor function in the elderly, adverse hemodynamic effects of dexmedetomidine may impact them more. Objective: To assess the incidence of adverse hemodynamic effects of dexmedetomidine in elderly ICU patients compared to other sedative agents to clarify the role of dexmedetomidine in this patient population. Methods: This was a single-center, retrospective study including mechanically ventilated elderly patients requiring sedative agents for ≥12 hours. The primary outcome evaluated was composite end point of incidence of bradycardia and hypotension. Secondary outcomes included incidence of each adverse event individually, hospital and ICU length of stay, and duration of mechanical ventilation. Results: There was no difference in adverse events between the two groups (58.7% vs 74.1% in the dexmedetomidine vs usual care groups, P =.074). There was no difference in hospital or ICU length of stay. Patients in the dexmedetomidine group were on the ventilator longer than patients in the usual care group with a median of 6 vs 3 days, respectively (P = 0.004). Conclusion: In this single-center, retrospective study dexmedetomidine had a similar incidence of adverse events in elderly patients compare to the usual care group.