Transversus Abdominis Plane Block with or without Intravenous Diclofenac Sodium as a Component of Multimodal Postoperative Analgesia Following Laparoscopic Cholecystectomy: A Randomised Clinical Study

Introduction: Multimodal analgesia is the recommended approach for treating post-operative pain after laparoscopic cholecystectomy. The Transversus Abdominis Plane (TAP) block is a recently introduced technique showing promising results. To control visceral and somatic pain adequately and to avoid use of opioids intra-operative diclofenac sodium, combined with TAP block as part of a multimodal approach, may be beneficial. Aim: To evaluate the efficacy of TAP block with or without intra-operative diclofenac sodium aqueous injection for controlling post-operative pain following laparoscopic cholecystectomy. Materials and Methods: A randomised, double-blinded study was conducted from February 2022 to October 2022 at Nil Ratan Sircar Medical College, Kolkata, West Bengal, India. Forty American Society of Anaesthesiology (ASA) physical status-I and II patients aged 20-50 years scheduled for elective laparoscopic cholecystectomy were divided into two groups of 20 patients each. Group A patients received bilateral Ultrasonography (USG) guided TAP block using 20 mL of 0.125% Bupivacaine on each side of the abdomen at the end of surgery. Group B patients received intravenous injection of diclofenac sodium aqueous 75 mg intravenous, intraoperatively, along with bilateral USG guided TAP block using 0.125% Bupivacaine. The primary outcome was the duration of post-operative analgesia (measured by the first request for rescue analgesia after the end of the operation at a VAS score of 4). Secondary outcomes included the total post-operative analgesic requirement (diclofenac sodium), pain score (VAS) over 24 hours in the post-operative period, and the incidence of complications such as nausea, vomiting, hypotension, and bradycardia. Patient Satisfaction Score ( PSS) was recorded for each patient before discharge. Statistical analysis was performed using Statistical Package for Social Sciences(SPSS) version 24.0 software. Continuous variables were expressed as mean and standard deviation, and categorical variables were expressed as percentages. Independent t-tests and chi-square tests were used for between-group comparisons, with a p-value <= 0.05 considered statistically significant. Results: Amongst total 40 patients included, divided into group A(mean age: 32.95 +/- 8.74 years, 6 males and 14 females) and group B(31.90 +/- 9.16 years, 5 males and 15 females) with 20 patients each, the demographic characteristics such as age, gender, height, and weight were similar in both groups. The duration of post-operative analgesia was longer in Group B (16.32 +/- 1.29 hours) than in Group A (7.85 +/- 1.04 hours). The total post-operative analgesic requirement was lower in Group B ( 32.95 +/- 20.9 mg) compared to Group A (58.33 +/- 17.14 mg). Visual Analogue Scale (VAS) scores were lower in Group B than in Group A. PSS was significantly higher in Group B patients (8.14 +/- 1.06) than in Group A patients (6.16 +/- 1.38). Conclusion: TAP block, along with intra-operative intravenous diclofenac sodium aqueous, as part of a multimodal regimen, provides superior post- operative analgesia compared to TAP block alone. It is also associated with improved patient satisfaction.