Adding magnesium sulfate to bupivacaine in transversus abdominis plane block for laparoscopic cholecystectomy: A single blinded randomized controlled trial.

INTRODUCTION AND AIM: Use of transversus abdominis plane block (TAP) in the management of postoperative pain after the laparoscopic cholecystectomy (LC) has been a common anesthetic practice. This study evaluates the effect of adding magnesium sulfate to bupivacaine in TAP block in LC regarding postoperative analgesia and analgesic consumption.

PATIENTS AND METHODS: Ninety patients of American Society of Anesthesiologists I and II was divided into three groups: Control group (C group, n = 30), bupivacaine group (B group, n = 30), bupivacaine magnesium group (M group, n = 30).

RESULTS: M group showed better analgesic profile in the 1(st) postoperative day in the form of lower mean visual analog scale score (2.8 ± 0.6 for C group, 2.1 ± 0.5 for B group, 2.2 ± 0.5 for M group, P < 0.001), longer duration of analgesia (7 ± 2.8 h for C group, 16 ± 2.5 h for B group, 19 ± 2.2 h for M group, P < 0.006), lower morphine consumption (2 ± 0.1 mg for C group, 0.9 ± 0.1 mg for B group, 0.5 ± 0.1 mg for M group, P < 0.011). There was a significant lower incidence of postoperative nausea and vomiting (PONV) (32% for C group, 6% B group, 7% M group, P < 0.004).

CONCLUSION: Adding MgSo4 as an adjuvant to bupivacaine in TAP block; during anesthesia for LC; improved postoperative analgesia in the form of increased duration, decreased analgesic requirements and PONV.