Comparison of dexmedetomidine and midazolam for monitored anesthesia care combined with tramadol via patient-controlled analgesia in endoscopic nasal surgery: A prospective, randomized, double-blind, clinical study (2007)

Abstract Monitored anesthesia care (MAC) may be applied for septoplasty or endoscopic sinus surgery in which an adequate sedation and analgesia without respiratory depression are desired for comfort of both the patient and the surgeon. Several combinations with different agents have been used for this purpose in these patients. However, analgesic properties for these agents have not been reported. The aim of this study was to investigate the analgesic and sedative effects of dexmedetomidine or midazolam infusion combined with tramadol that was used via patient-controlled analgesia (PCA), and to document the effects of these drugs on early cognitive functions. This prospective, randomized, double-blind, clinical study enrolled patients undergoing septoplasty or endoscopic sinus surgery at the Abant Izzet Baysal University Hospital, Bolu, Turkey, between February and September 2006. Patients were randomly allocated in a 1:1 ratio into 1 of 2 groups: the dexmedetomidine group (group D) patients received IV dexmedetomidine 1 μg/kg for 10 minutes followed by continuous infusion of 0.5 μg/kg · h−1; and the midazolam group (group M) patients were administered a loading dose of IV midazolam 40 μg/kg for 10 minutes followed by infusion at the rate of 50 μg/kg · h−1. A 1-minute bolus dose of IV tramadol (1.5 mg/kg) was administered in both groups 10 minutes after the administration of the primary drug, and continued via infusion using a PCA device. After baseline measurements, systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), heart rate (HR), oxygen saturation, and rate of respiration were recorded after the loading dose of study drug, after the bolus tramadol dose, at 10-minute intervals during the operation, and twice in the recovery rooms; 5 minutes after arrival and 5 minutes before discharge. Verbal rating score (VRS) and Ramsay sedation score were determined at baseline (after surgery was started), every 10 minutes thereafter until the end of the operation, and 2 times during recovery. All patients were assessed with the Wechsler Memory Scale-Revised at baseline (preoperatively) and 4 hours after the operation. Seventy patients were enrolled in the study and randomly assigned to 1 of 2 groups: group D (sex, male/female, 23/12; mean [SEM] age, 32.53 [2.07] years; mean [SEM] weight, 73.03 [2.41] kg) or group M (sex, male/female, 21/14; mean [SEM] age, 34.43 [1.83] years; mean [SEM] weight, 67.90 [2.32] kg). All hemodynamic parameters (SAP, DAP, MAP, HR) were significantly higher in group M compared with group D from the onset of the surgery to discharge time (P < 0.05). Pain and sedation scores were similar in both groups, but the amount of PCA-administered rescue tramadol was significantly higher in group M (P = 0.001). A higher, though not statistically significant, prevalence of adverse events (ie, hypotension, bradycardia, and perioperative nausea and vomiting) were observed in group D. Postoperative logical verbal memory and digit span values were significantly higher in group D when compared with group M (P < 0.05). Postoperative digit span and visual reproduction scores were significantly higher than preoperative values in group D (P < 0.05). Postoperative personality functioning scores were significantly higher than preoperative values in group M (P < 0.05). Based on VRS, Ramsay sedation scores, and surgeon and anesthesiologist satisfaction scores, dexmedetomidine or midazolam combined with tramadol PCA provided adequate analgesia and sedation in these adult patients undergoing septoplasty or endoscopic sinus surgery with MAC. A significantly larger amount of rescue tramadol was used by group M, suggesting that a better analgesic effect was achieved with dexmedetomidine.