Combined use of dexmedetomidine and propofol in monitored anesthesia care: a randomized controlled study

Backgroud: Although propofol and dexmedetomidine have been widely used for monitored anesthesia care, their adverse effects necessitate the search for better methods. Therefore, we performed this randomized controlled trial to evaluate the combined use of propofol and dexmedetomidine. Methods: Eighty-seven adult patients undergoing hand surgery under brachial plexus block were randomly allocated to receive 1.6 mu g/ml of the target effect site concentration of propofol (P group) and infusion of 0.4 mu g/kg/h dexmedetomidine following a loading dose of 1.0 mu g/kg for 10 min (D group). The M group received a half-dose of both drugs simultaneously. The maintenance dose was adjusted to maintain an Observer Assessment of Alertness/Sedation score of 3. Cardiorespiratory variables, adverse effects, and drug efficacy were observed. Results: The significantly higher mean arterial pressure (mmHg) in the D group [P group 86.9 (12.6), D group 96.0 (12.2), M group 85.6 (10.6), p = 0.004)] and a significantly higher heart rate (beat/min) in the P group were observed [P group 67.3 (9.0), D group 57.8 (6.9), M group 59.2 (7.4), p < 0.001)]. The M group had a significant lower incidence of airway obstruction (p < 0.001) and the D group had a higher incidence of bradycardia requiring atropine (p = 0. 001). The P group had higher incidences of hypoxia (p = 0.001), spontaneous movement (p < 0.001) and agitation (p = 0.001). The satisfaction scores of the patients (p = 0.007) and surgeon (p < 0.001) were higher in the M group. Onset time was significantly longer in the D group (p < 0.001). Conclusions: The combined use of propofol and dexmedetomidine provided cardiovascular stability with decreased adverse effects. Additionally, it led to a similar onset time of propofol and achieved higher satisfaction scores.