Effects of liposomal bupivacaine in preoperative fascia iliac block on postoperative pain and delirium in elderly patients undergoing hip fracture surgery: a study protocol for a randomised, parallel controlled prospective clinical study

Introduction Postoperative delirium (POD) is the most common acute fluctuating mental state change after hip fractures in older adults. Postoperative pain is a Grade A risk factor for POD and is closely related to the prognosis of patients undergoing hip fracture surgery. The fascia iliac block has a definite analgesic effect and few side effects, and several studies have reported that it reduces the occurrence of POD in patients undergoing general anaesthesia for hip fracture surgery. Liposomal bupivacaine is a local anaesthetic with a long half-life that significantly reduces the use of opioids and is conducive to patient prognosis and recovery. However, whether regional nerve block analgesia can decrease the occurrence of POD in elderly patients undergoing hip fracture surgery has not been reported.Methods and analysis This is a single-blinded, randomised, parallel-controlled prospective clinical study. Participants will be randomly assigned preoperatively to either the liposomal bupivacaine (ie, Exparel) or ropivacaine groups by block randomisation. Then, the occurrence of POD (primary outcome) and postoperative pain (secondary outcome) will be evaluated.Ethics and dissemination This research protocol complies with the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) 2013 guidelines and is approved by the Ethics Committee of Shanghai General Hospital (ID 2023–437). The original data are expected to be released in July 2029 on the ResMan original data-sharing platform (IPD-sharing platform) of the China Clinical Trial Registry, which can be viewed on the following website: http://www.medresman.org.cn.PROSPERO registration number ChiCTR2300074022.