Magnesium Sulphate as an Adjuvant to Epidural Ropivacaine for Postoperative Analgesia in Patients Undergoing Vaginal Hysterectomy

Abstract

Background: Effective postoperative analgesia following surgery is vital for early recovery and mobilization. This study aims to find out the analgesic efficacy of magnesium sulphate as an adjuvant to epidural ropivacaine for postoperative analgesia in patients undergoing vaginal hysterectomy under regional anaesthesia. Subjects and Methods: Forty consenting ASA I and II patients scheduled for vaginal hysterectomy under combined spinal epidural block were recruited. All patients received 2.5 ml hyperbaric bupivacaine intrathecally for the conduct of the procedure. Postoperatively, patients received ropivacaine with 50 mg magnesium sulphate (group RM) or ropivacaine with normal saline (group RS) through epidural catheter, when VAS ≥3 was achieved. Time to subsequent epidural top-up after study drug, VAS score, number of epidural top-ups, total dose of ropivacaine and diclofenac, haemodynamic parameters and sedation score were recorded. Data was analyzed using appropriate statistical tests. Results: Women who received magnesium with ropivacaine (group RM) had significantly longer mean time (214.15±91.03 min) to subsequent epidural top-up after the study drug as compared to group RS (203.41±129.11 min); p=0.015. The mean total dose of ropivacaine and diclofenac consumption in 24 hours was also less in group RM compared to group RS (p<0.05). The intraoperative and postoperative haemodynamics were comparable in both the groups. Conclusion: Epidural magnesium sulphate as an adjuvant to ropivacaine significantly prolonged the duration of postoperative analgesia, reduced the 24 hour ropivacaine and diclofenac requirements without any additional side effects.