Sedation for mechanically ventilated postoperative patients in the intensive care unit: comparative study between propofol and dexmedetomidine

ABSTRACT

Alpha 2 agonist dexmedetomidine is a new sedative and analgesic drug, which has been recently approved by FDA for use in ICU sedation. Dexmedetomidine is pharmacologically much more selective on alpha 2 receptors than clonidine. In the present study dexmedetomidine was compared to propofol as infusion for sedating 20 patients [10 patients in each group] admitted to ICU for postoperative short-term mechanical ventiiatory support [8-10 hrs] after major surgical procedures. Additional analgesics were supplied using nalbuphine iv bolus doses. Depth of sedation was measured continuously by using bispectral index neurosonic 1400 monitor. Hemodynamic and ventilator variables were recorded hourly Depth of sedation was equivalent in both groups by bispectral index scale 56 [44-67] for propofol group versus 49 [42-57] for dexmedetomidine group with non-significant difference [P= 0.41] between both groups. Although dexmedetomidine group showed more alertness and cooperation during ventiiator support and more rapid and easy extubation [extubation time 33 minutes in propofol group versus 32 minutes in dexmedetomidine group] [p= 0.7], but these changes were statistically non-significant Also propofol group required almost three times analgesic doses than for dexmedetomidine group [240 mg versus 80 mg]. No significant difference was found in mean arterial blood pressure or central venous pressure between both groups However heart rate showed significant reduction in dexmedetomidine group than in propofol group [p= 0.026]. No adverse events were recorded when related to the sedative infusions used in this study. It could be concluded that dexmedetomidine is a safe and an effective sedative agent in ICU postoperative patients as it provides safe profile and reduces analgesic requirements