Özet:
Background and objective: The aim of this study was to evaluate the efficacy of dexmedetomidine, an alpha(2)- adrenoceptor agonist, on intraoperative bleeding, anaesthetic drug requirement and postoperative pain. Methods: Forty patients scheduled for elective tympanoplasty and septorhinoplasty operations under general anaesthesia were included in the study. The patients were randomly assigned to receive either a dexmedetomidine 1 mu g kg(-1) bolus 10 min before induction of anaesthesia plus 0.5 mu g kg(-1) h(-1) infusions during maintenance or placebo. Mean arterial pressure was maintained between 60 and 80 mmHg. Perioperative mean arterial pressure, heart rate, time to extubation and time to awakening were recorded. Bleeding during surgery was assessed by the surgeon, blinded to the study drugs, both intraoperatively and postoperatively as a final personal opinion about the whole surgical process. Results: The heart rate and mean arterial pressure were significantly lower during induction, operation and extubation in the dexmedetomidine group (P < 0.05). Blood losses were lower in the dexmedetomidine group (P < 0.05). Propofol dose required for induction, and fentanyl and isoflurane consumption were significantly reduced in the dexmedetomidine group (P < 0.05). The total amounts of nitroglycerin and meperidine used were higher in the control group (P < 0.05). Conclusions: Dexmedetomidine decreased bleeding, postoperative analgesic requirements and intraoperative anaesthetic requirements and was associated with more stable haemodynamic responses to anaesthesia. We conclude that dexmedetomidine is a useful adjuvant to decrease bleeding when a bloodless surgical field is requested.