Comparison of Mean Duration of Post-operative Analgesia in Patients Undergoing Lower Abdominal Surgeries Receiving Ultrasound Guided Transversus Abdominis Plane (TAP) Block with Bupivacaine and Dexmedetomidine versus Bupivacaine and Dexamethasone

Objective

To compare the mean duration of post-operative analgesia in patients undergoing lower abdominal surgeries receiving ultrasound-guided TAP block with bupivacaine plus dexmedetomidine versus bupivacaine plus dexamethasone. Methodology: This randomized controlled trial (NCT07508202), conducted at the Department of Anesthesia, Pakistan Institute of Medical Sciences (PIMS) in Islamabad from March 26, 2026, to June 26, 2026, enrolled a total of 60 patients aged 18–60 years with ASA physical status I–II who were scheduled for lower abdominal procedures, and divided them equally into two groups of 30 patients each. In Group A, a bilateral ultrasound-guided transversus abdominis plane (TAP) block was performed at the end of surgery using 20 mL of 0.25% bupivacaine combined with 4 mg of dexamethasone, whereas Group B received the same volume of 0.25% bupivacaine along with 0.5 μg/kg of dexmedetomidine. The primary outcome measured was the duration of postoperative analgesia, defined as the time interval from the completion of the block to the patient's first request for rescue analgesia, with the aim of determining which adjuvant offers superior prolongation of analgesic effect in lower abdominal surgeries.