Effect of 4-point transversus abdominal plane block on diaphragm thickness in patients undergoing laparoscopic cholecystectomy

Introduction: This study investigates the effect of a 4-point transversus abdominis plane (TAP) block on diaphragm thickness (DT) and post-operative recovery following laparoscopic cholecystectomy (LC). This study aims to evaluate whether the 4-point TAP block preserves DT closer to baseline values and enhances post-operative pain control and recovery quality. Patients and Methods: This prospective randomised controlled trial was conducted at a tertiary care hospital. A total of 86 American Society of Anesthesiologists I–II patients aged 18–65 years undergoing elective LC were randomly assigned into two groups. Group B received a 4-point TAP block postoperatively, whereas Group C received no interventional analgesia. In Group B, 10 mL of 0.25% bupivacaine was administered bilaterally under ultrasound guidance to the upper abdominal (Th6–Th9) and typical TAP (T10–T12) regions. DT, the primary outcome, was measured by ultrasonography preoperatively and at 5 and 30 min post-extubation. Secondary outcomes included Visual Analogue Scale pain scores and Quality of Recovery-15 (QoR-15) scores. Statistical analysis was performed using SPSS v22.0. The Shapiro–Wilk test, Chi-square, independent samples t -test, Mann–Whitney U -test and repeated-measures ANOVA were used. P < 0.05 was considered statistically significant. Based on power analysis, 86 patients were sufficient. Results: Group B demonstrated significantly better preservation of inspiratory DT, lower post-operative pain scores and higher QoR-15 scores compared to Group C ( P < 0.05). Conclusions: The 4-point TAP block improves DT preservation and enhances post-operative pain control and recovery following LC. Further large-scale studies are warranted to support these findings.