Dexmedetomidine versus midazolam and propofol for sedation in critically ill patients: Mining the Medical Information Mart for Intensive Care data

Yiyan Song, Shaowei Gao, Wulin Tan, Zeting Qiu, Huaqiang Zhou, Yue Zhao


Background: The benefits of dexmedetomidine on reducing mortality and length of intensive care unit (ICU) stay are still controversial. We aimed to evaluate the superiority of dexmedetomidine by comparing it with midazolam and propofol.
Methods: Subjects who were given dexmedetomidine, midazolam and propofol exclusively as sedatives in the Beth Israel Deaconess Medical Center between 2001 and 2012 were identified from the Medical Information Mart for Intensive Care (MIMIC) III database. Univariate, multivariate and stratified analysis was performed to compare the mortality and length of ICU stay between the dexmedetomidine, midazolam and propofol groups. To compare the depth of sedation between the midazolam and propofol group, we used propensity score matching (PSM) to create comparable units and their Richmond Agitation Sedation Score (RASS) were analyzed.
Results: A total of 1,542 unique ICU records were identified in the MIMIC-III database, among which 163 belonged to the dexmedetomidine group and 531 belonged to the midazolam group and 848 belonged to the propofol group. Mortality was decreased in dexmedetomidine group compared with midazolam group (OR 15.25; 95% CI, 5.29–64.80, P<0.001) and propofol group (OR 5.51; 95% CI, 1.91–23.45, P=0.006). In patients with high Simplified Acute Physiologic Score (SAPS) II (>52), midazolam was related to a higher mortality (~50%). But competing risk analysis revealed that dexmedetomidine was associated with longer ICU stay (P<0.001). There was no significant difference in the RASS between propofol and midazolam group (P=0.300).
Conclusions: Dexmedetomidine was significantly related to lower mortality when compared with midazolam and propofol. Midazolam had a comparably higher mortality than propofol and dexmedetomidine in patients with high SAPS II. Propofol and midazolam were equivalent in sedative efficacy. Further evaluation is needed.