Effect of Ultrasound-Guided Transversus Abdominis Plane (Tap) Block on Postoperative Pain and Recovery Following Open Abdominal Surgery: A Prospective Comparative Study

Background: Open abdominal surgery produces severe somatic pain from the abdominal wall incision that delaysmobilisation and oral intake and drives opioid consumption. The ultrasound-guided transversus abdominis plane (TAP) blockanaesthetises the anterior rami of T6–L1 in the neurofascial plane between the internal oblique and transversus abdominismuscles. We evaluated its effect on postoperative pain, opioid requirement and early recovery after open abdominal surgery.Materials and Methods: In this prospective comparative study, 45 adult patients (ASA I–III) undergoing elective or urgentopen abdominal surgery under general anaesthesia received either a bilateral ultrasound-guided TAP block with 0.25%bupivacaine at the end of surgery in addition to standard multimodal analgesia (TAP group, n = 23) or standard multimodalanalgesia alone (control group, n = 22). Pain was assessed on an 11-point numerical rating scale (NRS) at rest (0, 2, 4, 6, 12,24 and 48 h) and on movement (2, 6, 12, 24 and 48 h). The primary outcome was the area under the rest-NRS–time curve over0–24 h (AUC0–24). Secondary outcomes were time to first rescue analgesia, 24-h intravenous morphine-equivalentconsumption, postoperative nausea and vomiting (PONV), Quality of Recovery-15 (QoR-15) score at 24 h and times to firstambulation, oral intake and discharge readiness. Results: Groups were comparable for age, sex, body mass index, ASA class,procedure and operative duration. Rest-NRS AUC0–24 was lower in the TAP group (80.5 ± 6.4 vs 104.9 ± 6.6 score·h; meandifference −24.4 (−28.3 to −20.5); p < 0.001), with lower rest and movement NRS at every time point up to 48 h. Median timeto first rescue analgesia was 335 min versus 83 min (log-rank p < 0.001), and 24-h morphine-equivalent consumption wasreduced by 52% (8.0 ± 1.5 vs 16.6 ± 1.1 mg; p < 0.001). Baseline-adjusted QoR-15 at 24 h was 16.5 points higher (95% CI14.1 to 18.8; p < 0.001). TAP patients ambulated 7.8 h earlier, resumed oral intake 4.8 h earlier and reached discharge readiness17.1 h earlier (all p < 0.001). Postoperative vomiting was less frequent (4.3% vs 27.3%; p = 0.047); any PONV and antiemeticuse did not differ significantly. Conclusion: Adding an ultrasound-guided TAP block to multimodal analgesia after openabdominal surgery substantially reduced pain at rest and on movement, halved 24-h opioid consumption, prolonged the timeto first rescue analgesic and translated into a clinically meaningful improvement in quality of recovery and earlier attainmentof recovery milestones.