Magnesium sulfate as an adjuvant in serratus anterior plane block for postoperative pain management in modified radical mastectomy: A randomized controlled trial

Background: Although modified radical mastectomy (MRM) is a frequently performed surgical procedure, patients may experience pain both during and after the operation. Adding magnesium sulfate to a local anesthetic can make its effects last longer. The objective of this research was to find out whether patients having mastectomy could benefit from using magnesium sulfate as an adjuvant in serratus anterior plane blocks (SAPB). Methods: This randomized, controlled, double-blinded study was performed on 40 women aged 18 to 65 who underwent MRM under general anesthesia. Patients were divided into two equal groups. Both groups received SAPB using bupivacaine 0.5% (28.5ml) plus 1.5 ml of magnesium sulfate (750 mg) Group BM and 1.5 ml of normal saline Group B. Results: The two groups did not differ significantly in terms of the need for intraoperative fentanyl consumption. The time it took for group BM to experience their initial rescue analgesia was significantly longer than in group B (p<0.001). The total morphine consumed by group BM was significantly less than that of group B (p<0.001). The visual analog scale was significantly lower at 4h, 8 h, and 12 h in group BM than in group B (p<0.05). Conclusion: By combining magnesium sulfate with bupivacaine in SAPB, postoperative pain and the requirement for postoperative analgesics were decreased with minimum adverse effects.