Dexmedetomidine versus propofol/midazolam for long-term sedation during mechanical ventilation

To compare dexmedetomidine (DEX) with standard care (SC, either propofol or midazolam) for long-term sedation in terms of maintaining target sedation and length of intensive care unit (ICU) stay. A pilot, phase III, double-blind multicenter study in randomized medical and surgical patients (n = 85) within the first 72 h of ICU stay with an expected ICU stay of ≥48 h and sedation need for ≥24 h after randomization. Patients were assigned to either DEX (≤1.4 μg kg−1 h−1; n = 41) or SC (n = 44), with daily sedation stops. Non-inferiority of DEX versus SC was not confirmed. Target Richmond agitation–sedation score (RASS) was reached a median of 64% (DEX) and 63% (SC) of the sedation time (ns). The length of ICU stay was similar in DEX and SC. Patients with RASS target 0–3 (DEX 78%, SC 80%) were at target sedation 74% (DEX) and 64% (SC) of the time (ns), whereas those with RASS target −4 or less reached the target 42% (DEX) and 62% (SC) of the time (P = .006). Post hoc analyses suggested shorter duration of mechanical ventilation for DEX (P = 0.025). This pilot study suggests that in long-term sedation, DEX is comparable to SC in maintaining sedation targets of RASS 0 to −3 but not suitable for deep sedation (RASS −4 or less). DEX had no effect on length of ICU stay. Its effects on other relevant clinical outcomes, such as duration of mechanical ventilation, should be tested further.