Impact of Dexmedetomidine on Hemodynamics, Plasma Catecholamine Levels, and Delirium Incidence Among Intubated Patients in the ICU--A Randomized Controlled Trial.

Objective: To investigate the impact of various sedative medications on hemodynamics and plasma levels of epinephrine (E) and norepinephrine (NE) in mechanically ventilated patients postoperatively in the intensive care unit (ICU).

Methods: Ninety-seven patients admitted to the ICU undergoing postoperative mechanical ventilation with tracheal intubation and continuous analgesic sedation following general anesthesia were randomly assigned to either the observation group (dexmedetomidine) (n = 49) or the control group (propofol) (n = 48) in this randomized controlled trial. Upon transfer to the ICU, vital signs (heart rate [HR], respiratory rate [RR], mean arterial pressure [MAP]) were recorded prior to the initiation of the sedation treatment (T0), at one-hour post sedation (T1) and two hours following tracheal extubation (T2), plasma levels of epinephrine (E) and norepinephrine (NE) were measured at these time points. The incidence of delirium was recorded in both groups.

Results: MAP between the two groups at both T0 and T1 At T2 plasma NE and HR were found to be lower in the observation group compared to the control group (P < 0.001). Among the patients receiving antihypertensive medication in the ICU, NE levels were significantly lower in the observation group compared to the control group (P = 0.019) Among the patients not receiving antihypertensive medication, both NE (P < 0.001) and MAP (P = 0.001) levels were lower in the observation group compared to the control group. The incidence of delirium in the observation group (dexmedetomidine) was not significantly different from that in the control group (propofol).

Conclusion: With dexmedetomidine sedation, blood pressure fluctuated less, plasma catecholamine levels were lower, and sympathetic inhibition was stronger in patients before and after extubation. However, it did not significantly reduce the incidence of postoperative delirium.