The analgesic efficacy of ultrasound-guided transversus abdominis plane block for retroperitoneoscopic renal surgery: A randomized controlled study
Abstract Background Ultrasound-guided lateral transversus abdominis plane (TAP) block can provide definite analgesia to the anterior abdominal wall. However, whether this method is useful in renal surgery involving access through the lateral abdominal wall remains unknown. Therefore, the study aimed to evaluate the analgesic efficacy of lateral TAP block for retroperitoneoscopic partial or radical nephrectomy. Method In this prospective, randomized, double-blind, placebo-controlled trial, eligible patients were randomized into the intervention (T) or control (C) groups. After anaesthesia induction, ultrasound-guided lateral TAP block was performed preoperatively with 30 ml of 0.4% ropivacaine and an equivalent amount of normal saline in groups T and C, respectively. The primary outcomes were opioid consumption during surgery and in the first 24 h after surgery. Secondary outcomes were postsurgical pain intensity upon immediately awakening from anaesthesia and at 0.5, 1, 2, 6, 12, and 24 h after surgery as well as recovery quality variables including the incidence of postoperative nausea and vomiting (PONV), sleep quality, time to first ambulation, drainage and length of hospital stay. Results A total of 104 patients were enrolled and randomized: 53 and 51 in groups T and C, respectively. Laparoscopic surgery was converted to open surgery in one patient. Thus, he was excluded from the analysis. The median intraoperative and postoperative opioid consumption (oral morphine equivalent dose, o-MED) in the first 24 h after surgery were 105.0 and 32.5 mg in Group C, respectively, and the corresponding values in Group T were 121.0 and 39.7 mg, all of which were not significant (P = 0.284 and 0.311). Postsurgical pain intensity at all time points was comparable between the groups (all P > 0.05). Intergroup differences in the recovery quality variables were not significant (all P > 0.05). Conclusion Our findings demonstrated that preoperative lateral TAP could not decrease intraoperative or postoperative opioid consumption or pain intensity in the first 24 h after surgery, nor could it promote postoperative recovery in patients undergoing laparoscopic renal surgery through retroperitoneal access.