Efficacy and Safety of Pericapsular Nerve Group Block (PENG) in Hip Surgery Under General Anaesthesia: A Systematic Literature Review and Meta-Analysis.

Background: The pericapsular nerve group (PENG) block is a novel ultrasound-guided regional technique that may provide analgesia to patients undergoing hip surgery. It has been extensively studied in recent years, but the evidence of superiority over other regional anaesthetic techniques is inconclusive. This review aimed to compare outcomes of the PENG block in patients undergoing hip surgery with standard techniques under general anaesthesia. Methods: PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed throughout the preparation of this review. Randomised trials from electronic databases were included. We investigated postoperative pain scores, required analgesia, and adverse events associated with the block. Results: Ten studies satisfied the criteria to be included in the meta-analysis. Data from 646 patients were analysed, in which 321 patients received PENG block and 325 were included in the comparative groups. Pain scores at rest, at 24 h (p = 0.04) and 48 h (p = 0.02) were lower in patients who had received the PENG block. This group also required a smaller amount of opioids at 24 h after the procedure, but this difference was not statistically significant (p = 0.53); while a similar non-significant reduction in opioid consumption was also observed at 48 h. Although PENG seems to delay the time to the first analgesic request, we failed to prove a statistically significant difference (p = 0.83). Patient satisfaction also seems to be better in the PENG group, but not in a statistically significant way. No important side effects related to the block were described. Conclusions: PENG block for major hip surgery offers better postoperative analgesia, with possibly less opioid consumption. It seems to prolong the time to the first analgesic but does not significantly affect common side effects of anaesthesia/analgesia such as PONV or duration of hospital stay.