Dexmedetomidine versus remifentanil infusion for controlled hypotension in shoulder arthroscopy: a comparative study

Study objective The correct performance of the shoulder arthroscopic technique requires appropriate visualization through a video camera which raises the need for providing satisfactory bloodless surgical field. The current study was conducted to evaluate the clinical efficacy of dexmedetomidine infusion compared to that of remifentanil for controlled hypotension in patients undergoing shoulder arthroscopy. Patients and methods Forty patients undergoing elective arthroscopic shoulder surgery under general anesthesia were enrolled in the current study. Patients were randomly distributed into one of two equal groups: dexmedetomidine group (D group) and remifentanil group (R group) according to the agent used for controlled hypotension. In group D, IV dexmedetomidine l mu g/kg was infused over 10 min before anesthesia induction, followed by a continuous infusion of 0.3-0.6 mu g/kg/h during the operation. In group R, 1 mu g/kg remifentanil IV bolus was administered before induction of anesthesia and continued 0.25-0.50 mu g/kg/min during the operation. In both groups, the drug infusion was titrated to achieve a mean arterial pressure (MAP) of 60-70 mmHg. Hemodynamic parameters, surgical field condition, recovery profile, and the incidence of perioperative adverse events were assessed. Results Controlled hypotension was achieved successfully in both study groups. There was no intergroup significant difference as regards the intraoperative MAP and heart rate (HR) recordings (P> 0.05) except for the significantly lower HR recorded after extubation,30 min and 1 h postoperative in group D when compared with group R (P< 0.05). The surgical field condition was satisfactory on surgeon assessment in both groups (P> 0.05). Extubation time, time to reach modified Aldrete score >= 9 and time to 1st postoperative analgesic requirement were significantly longer in the group D when compared with group R (P< 0.05). Postoperative Ramsay sedation score recordings were significantly higher in the group D when compared with group R (P< 0.05) except at 2 h postoperative recordings and all the VAS score recordings were significantly lower in group D when compared with group R (P< 0.05). There was no intergroup significant difference as regards the incidence of perioperative adverse events. Conclusion Both remifentanil and dexmedetomidine can induce adequate levels of hypotensive anesthesia and satisfactory surgical field visibility in patients undergoing shoulder arthroscopy under general anesthesia. Patients treated with dexmedetomidine had better quality and more extended postoperative analgesia but longer postoperative anesthesia recovery and higher postoperative sedation scores when compared with remifentanil.