Effect of ultrasound-guided transverse abdominal plane block on postoperative analgesia in patients undergoing orthotopic liver transplantation under general anesthesia

Abstract

Objective To evaluate the effect of ultrasound-guided transverse abdominal plane block(TAPB)on postoperative analgesia in patients undergoing orthotopic liver transplantation under general anesthesia. Methods Forty American Society of Anesthesiologists physical status Ⅲ-Ⅴ patients, with body mass index of 18-24 kg/m2, aged 18-64 yr, undergoing elective modified piggy-back orthotopic liver transplantation, were divided into 2 groups(n=20 each)by a random number table method: TAPB combined with general anesthesia group(TAPB-GA group)and general anesthesia group(GA group). In TAPB-GA group, two-point TAPB was performed below bilateral costal margins under ultrasound guidance after induction of general anesthesia, and a mixture of 0.33% ropivacaine 15 ml plus 0.5% dexamethasone 0.5 ml was injected into each point.The equal volume of normal saline was injected into each point instead in group GA.Patient-controlled intravenous analgesia was performed with sufentanil 2 μg/kg after operation in both groups.Sufentanil 5 μg was intravenously injected as rescue analgesic, and the visual analog scale score was maintained ≤3 within 48 h after operation.The intraoperative consumption of remifentanil and extubation time after operation were recorded.The requirement for sufentanil as rescue analgesic and development of nausea and vomiting, itching and respiratory depression were recorded within 48 h after surgery. Results Compared with group GA, the intraoperative consumption of remifentanil and requirement for sufentanil as rescue analgesic within 48 h after surgery were significantly reduced, the time of extubation was shortened, and the incidence of nausea and vomiting, itching and respiratory depression was decreased in group TAPB-GA(P<0.05). Conclusion Ultrasound-guided TAPB can provide better efficacy of postoperative analgesia with fewer adverse reactions in patients undergoing orthotopic liver transplantation under general anesthesia. Key words: Nerve block; Abdominal muscles; Liver transplantation; Pain, postoperative