Sedation effects by dexmedetomidine versus propofol in decreasing duration of mechanical ventilation after open heart surgery.

OBJECTIVE: : The objective of this study was to compare the suitability (efficacy and safety) of dexmedetomidine versus propofol for patients admitted to the intensive care unit (ICU) after the cardiovascular surgery for the postoperative sedation before weaning from mechanical ventilation.

BACKGROUND: Sedation is prescribed in patients admitted to the ICU after cardiovascular surgery to reduce the patient discomfort, ventilator asynchrony, to make mechanical ventilation tolerable, prevent accidental device removal, and to reduce metabolic demands during respiratory and hemodynamic instability. Careful drug selection for sedation by the ICU team, postcardiovascular surgery should be done so that patients can be easily weaned from mechanical ventilation after sedation is stopped to achieve a shorter duration of mechanical ventilation and decreased the length of stay in ICU.

METHODS: A total of 50 patients admitted to the ICU after cardiovascular surgery, aged from 18 to 55 years and requiring mechanical ventilation on arrival to the ICU were enrolled in a prospective and comparative study. They were randomly divided into two groups as follows: Group D patients (n = 25) received dexmedetomidine in a maintenance infusion dose of 0.8 μg/kg/h and Group P patients (n = 25) received propofol in a maintenance infusion dose of 1.5 mg/kg/h. The patients were assessed for 12 h postoperatively, and dosing of the study drug was adjusted based on sedation assessment performed with the Richmond Agitation-Sedation Scale (RASS). The patients were required to be within the RASS target range of -2 to +1 at the time of study drug initiation. At every 4 h, the following information was recorded from each patient such as heart rate (HR), mean arterial pressure (MAP), arterial blood gases (ABG), tidal volume (TV), exhaled TV, maximum inspiratory pressure, respiratory rate and the rapid shallow breathing index, duration of mechanical ventilation, midazolam and fentanyl dose requirements, and financial costs.

RESULTS: The study results showed no statistically significant difference between both groups with regard to age and body mass index. Group P patients were more associated with lower MAP and HR than Group D patients. There was no statistically significant difference between groups with regard to ABG findings, oxygenation, ventilation, and respiratory parameters. There was significant difference between both the groups in midazolam and fentanyl dose requirement and financial costs with a value of P < 0.05.

CONCLUSION: Dexmedetomidine is safer and equally effective agent for the sedation of mechanically ventilated patients admitted to the ICU after cardiovascular surgery compared to the patients receiving propofol, with good hemodynamic stability, and equally rapid extubation time.