Standard local infiltration vs. additional laparoscopic-guided transverse abdominis plane block in laparoscopic cholecystectomy: interim analysis of double blinded randomized control study

Abstract

INTRODUCTION & OBJECTIVES: Transverse abdominal plane block (TAP) is a new technique used in perioperative analgesia. It has shown a clear benefit in long laparoscopic procedures. Current trial evaluates its efficacy in uncomplicated laparoscopic cholecystectomy. METHODS: A single centre double blinded randomized control trial was designed with 45 patients to each group based on 80% power at a p<0.01. Patients who underwent elective uncomplicated laparoscopic cholecystectomy were randomized in to local port site infiltration of bupivacaine and additional TAP block groups. Primary efficacy variables were postoperative pain score and requirement for opioids measured every six hourly. Duration of immobilization and hospital stay were some of the secondary variables. An interim analysis was done at 8 months. RESULTS: Thirty eight patients were randomized to two groups. Twenty-two (58%) were given TAP blocks. The male:female ratio (p=0.24), age (p=0.4), indication for surgery (p=0.34), ASA (p=0.45) and BMI (p=0.58) were similar in the two groups. There was no difference in operating time (p=0.28), intraoperative findings (p=0.4) and the difficulty index (p=0.26). Six hourly pain scores till the time of discharge, total and six hourly opioid dose, number of vomiting episodes, total hospital stay (p=0.98) and time to mobilize out of the bed (p=0.63) were similar in the two groups. CONCLUSION: TAP block does not have an added advantage over standard port site infiltration in uncomplicated laparoscopic cholecystectomy.