Dexmedetomidine has a sedative analgesic property without respiratory depression. This study evaluated the efficacy of dexmedetomidine as an appropriate sedative drug for monitored anesthesia care (MAC) in outpatients undergoing cataract surgery on both eyes compared with combination of propofol and alfentanil.

Thirty-one eligible patients were randomly divided into two groups on the first operation day. Dexmedetomidine was administered in group D at 0.6 µg/kg/h, and propofol and alfentanil was infused concomitantly in group P at a rate of 2 mg/kg/h and 20 µg/kg/h, respectively. Sedation was titrated at Ramsay sedation score 3. Iowa satisfaction with anesthesia scale (ISAS) of the patients was evaluated postoperatively. Systolic blood pressure (SBP), heart rate (HR), respiration rate (RR), and peripheral oxygen saturation (SpO₂) were recorded throughout the surgery. For the second operation, the group assignments were exchanged.

Postoperative ISAS was 50.3 (6.2) in group D and 42.7 (8.7) in group P, which was statistically significant (P < 0.001). SBP was significantly lower in group D compared with group P from the beginning of the operation. HR, RR, and SpO₂ were comparable between the two groups. There were 8 cases (25.8%) of hypertension in group P, and 1 case (3.2%) in group D (P < 0.05). In contrast, 1 case (3.2%) of hypotension and 1 case (3.2%) of bradycardia occurred in group D.

Compared with the combined use of propofol and alfentanil, dexmedetomidine could be used appropriately for MAC in cataract surgery with better satisfaction from the patients and a more stable cardiovascular state.