Abstract PR297

Abstract

Background & Objectives: General anaesthesia (GA) is the standard technique used for breast surgery but is associated with considerable postoperative pain, nausea and vomiting. Paravertebral block (PVB) has been suggested as an ideal alternative to GA for breast surgeries. Benefits include reduction in intraoperative analgesic and anaesthetic requirement, postoperative pain relief and reduction in postoperative nausea and vomiting. We aimed to assess the efficacy of morphine or dexmedetomidine as adjuvant in PVB for postoperative analgesia in patients undergoing modified radical mastectomy. Materials & Methods: Forty five women aged 18-60 years with unilateral carcinoma breast belonging to either ASA-1 or 2 undergoing modified radical mastectomy with or without axillary clearance were randomly assigned into group BM and BD where they received PVB with 20 ml of bupivacaine 0.25% with morphine 3 mg or dexmedetomidine 1 μg/kg, respectively. A standardised GA was induced after confirming the onset of PVB. Patient characteristics, intraoperative consumption of fentanyl and propofol were noted. Postoperatively, numerical rating scores for pain at rest and movement, nausea and vomiting, sedation scores, consumption of morphine, time of administration of first rescue analgesic and the duration of analgesia were recorded. Results: Patient demographics, duration of surgery and anaesthesia, intraoperative consumption of fentanyl and ephedrine were comparable between the two groups. Propofol consumption in group BD was significantly lower [654.35 (217.08) mg vs 822.73 (305.43) mg, p=0.0381]. Numerical rating score for pain at rest and upon movement was significantly lower in group BM at 2, 6, 12 and 18 h postoperatively. The number of patients requiring intravenous morphine during the first 2 h postoperatively was significantly lower (p=0.0061) in group BM. Duration of analgesia was significantly prolonged in group BM [1172.1 (194.4) min] than group BD [501.7 (159.7) min] (p=0.0001). The overall incidence of postoperative nausea and vomiting was low and comparable between the two groups. Sedation scores were comparable at all time intervals. Conclusion: Morphine as an adjuvant to bupivacaine in PVB for modified radical mastectomy was more efficacious than dexmedetomidine in providing prolonged postoperative analgesia both at rest and on movement, and also in reducing postoperative analgesic requirement.