The efficacy of dexmedetomidine versus melatonin in patients undergoing modified radical mastectomy

Abstract

Background Elderly patients are more susceptible to the adverse effects of anesthesia due to reduction of the margin of safety. So, premedication before operation in elderly patients has become an important issue. Objective The aim was to evaluate the efficacy of premedication with dexmedetomidine versus melatonin on sedation, analgesia, and inflammatory response in elderly patients. Patients and methods This study was conducted on 80 healthy female patients of American Society of Anesthesiologists physical status I, II scheduled for modified radical mastectomy under general anesthesia. The patients were randomly divided into two equal groups: Group I (n=40) received 5 mg melatonin and group II (n=40) received 1 μg/kg dexmedetomidine by intravenous infusion. The heart rate, mean arterial blood pressure, and oxygen saturation were measured perioperatively. Visual analog scale (VAS) for anxiety and pain and the sedation score were measured. Also, biochemical analyses for interleukin-6 (IL6) and liver function tests were measured and any adverse effects reported. Results There was no statistically significant difference in hemodynamics between the groups. VAS for anxiety was significantly lower in the melatonin group. VAS pain scores was significantly lower in the dexmedetomidine group (P=0.0001). The sedation score showed that the sedation level in the melatonin group was lower than dexmedetomidine groups preoperatively and postoperatively but with significant difference only at 30 min postoperatively. Plasma levels of IL6 before premedication (T0) showed highly significant difference between the studied groups (P Conclusion Premedication with dexmedetomidine has good postoperative analgesia and sedation with less inflammatory stress response than melatonin, with superiority of melatonin in the reduction of anxiety.