Comparison between Magnesium Sulphate and Buprenorphine as an Adjuvant to Bupivacaine in Ultrasound-Guided Transverse Abdominis Plane Block for Post-Operative Analgesia in Parturients Undergoing Caesarean Section

Abstract

Background: This study evaluates the comparative efficacy of Magnesium Sulphate and Buprenorphine as adjuvants to Bupivacaine in an ultrasound-guided Transversus Abdominis Plane (TAP) block for post-operative analgesia in parturients undergoing Caesarean section.

Methods: A prospective, double-blinded, randomized controlled study was conducted on sixty patients (n=60) aged 18–40 years with ASA grade 2 and 3, undergoing elective or emergency Caesarean section. Patients were randomly divided into two groups: Group M (n=30) received 18 ml of 0.25% Bupivacaine with 1 ml Magnesium Sulphate (500 mg) and 1 ml normal saline per side, while Group B (n=30) received 18 ml of 0.25% Bupivacaine with 0.5 ml Buprenorphine (150 mcg) and 1.5 ml normal saline per side. The primary outcome was the duration of post-operative analgesia, while secondary outcomes included the time to first rescue analgesic requirement, total rescue analgesia required over 24 hours, pain intensity using the Visual Analog Scale (VAS), and hemodynamic stability.

Results: Group B demonstrated significantly prolonged analgesia (9.72±0.879 hours) compared to Group M (7.45±1.03 hours) (p<0.001). The requirement for rescue analgesia was lower in Group B (1.7±0.466 doses) than in Group M (2.13±0.68 doses) (p=0.045). VAS scores were significantly lower in Group B at 8, 12, 18, and 24 hours post-operatively (p<0.05). Hemodynamic parameters remained stable in both groups.

Conclusion: The addition of Buprenorphine to Bupivacaine in TAP block provides prolonged post-operative analgesia, reduces the need for rescue analgesia, and minimizes pain intensity without significant hemodynamic alterations. Buprenorphine appears superior to Magnesium Sulphate as an adjuvant for enhanced post-operative pain management in Caesarean section patients.