MAGNESIUM SULFATE VS. DEXAMETHASONE AS ADJUVANTS IN ULTRASOUND-GUIDED TRANSVERSUS ABDOMINIS PLANE BLOCK FOR EMERGENCY LAPAROTOMY: A COMPARATIVE EFFICACY STUDY

V. Sharipova¹, S. Yuldosheva², I. Fokin³, M. Narimova², U. Abdirimov² | ¹Anesthesiology and Critical Care Unit, Republican Scientific Emergency Medical Centre, Tashkent, Uzbekistan; ²Department of Anesthesiology, Republican Research Center of Emergency Medicine, Tashkent, Uzbekistan; ³Head of Department of Anesthesiology, Republican Research Center of Emergency Medicine, Tashkent, Uzbekistan

Abstract

Background and Aims. Postoperative pain management in emergency laparotomy remains a clinical challenge. Ultrasound-guided Transversus Abdominis Plane (TAP) block has emerged as a cornerstone of multimodal analgesia, aimed at reducing opioid consumption and facilitating early mobilization. To improve the quality and duration of the sensory blockade, different pharmacological adjuvants are used. This study evaluates the comparative efficacy and safety of magnesium sulfate (MgSO₄) and dexamethasone as adjuvants to bupivacaine in TAP blocks for patients undergoing emergency abdominal surgery.
Methods. A prospective comparative study was performed with 58 patients slated for emergency laparotomy. Participants were allocated into two intervention groups: Magnesium Group (n=25): Received an ultrasound-guided TAP block with 18 ml of 0.25% bupivacaine supplemented with 300 mg of magnesium sulfate. Dexamethasone Group (n=33): Received the same block with 18 ml of 0.25% bupivacaine supplemented with 4 mg of dexamethasone. Postoperative monitoring included comprehensive hemodynamic assessment (HR, MAP, and SpO₂ ) and metabolic profiling (blood glucose levels). Pain intensity was quantified using the Numeric Rating Scale (NRS). The primary endpoints were the time to the first rescue analgesic request and total 24-hour morphine-equivalent consumption.
Results. Hemodynamic stability and respiratory parameters remained consistent across both cohorts, with no adverse events recorded. The magnesium group exhibited a statistically significant prolongation in the duration of analgesia. The mean time to the first analgesic requirement was 706.36 ± 36.54 minutes in the magnesium group, compared to 411.15 ± 3.9 minutes in the dexamethasone group (p < 0.05). Furthermore, total opioid requirements were significantly lower in the magnesium cohort (8.18 mg morphine equivalent) relative to the dexamethasone cohort (27.27 mg morphine equivalent).
Conclusions. The integration of magnesium sulfate (300 mg) as an adjuvant in ultrasound-guided TAP blocks significantly enhances the analgesic profile by extending the duration of the blockade and minimizing systemic opioid dependence in the immediate postoperative period following emergency laparotomy. These findings suggest that magnesium sulfate is a superior alternative to dexamethasone for optimizing regional anesthesia in emergency surgical settings.