Efficacy of nonopioid analgesics and regional techniques for perioperative pain management in laparoscopic gynecological surgery: a systematic review and network meta-analysis

Background: The optimal approach for perioperative pain management in laparoscopic gynecological surgery is unclear due to a lack of comprehensive analysis, which limits the development of evidence-based enhanced recovery after surgery protocols. This study aimed to conduct a systematic review and network meta-analysis to support clinical decision-making for optimal analgesia. Materials and methods: This study conducted a systematic literature search in PubMed, Embase, CENTRAL, Web of Science, and CINAHL from inception to 3 December 2021, and updated on 19 August 2022. Randomized controlled trials comparing the perioperative use of nonopioid analgesics and regional techniques in adults undergoing elective laparoscopic gynecological surgery under general anesthesia were included in the analysis, either alone or in combination. The co-analgesic interventions during the perioperative period for the intervention and control groups of each eligible study were also considered. We assessed the risk of bias using the Risk of Bias 2 tool and evaluated the certainty of evidence using the Confidence in Network Meta-Analysis (CINeMA) approach. A Bayesian network meta-analysis was used to estimate the efficacy of the analgesic strategies. The primary outcomes were pain score at rest and cumulative oral morphine milligram equivalents at 24 h postoperatively. Results: Overall, 108 studies with 9582 participants and 35 different interventions were included. Compared with inert treatments, combinations of two or more interventions showed better efficacy and longer duration in reducing postoperative pain and opioid consumption within 24 h than monotherapies, and showed stepwise enhanced effects with increasing analgesic modes. In combination therapies, regional techniques that included peripheral nerve blocks and intraperitoneal local anesthetics, in combination with nonopioid systemic analgesics, or combining local anesthetics with adjuvant drugs, were found to be more effective. Monotherapies were found to be mostly ineffective. The most effective peripheral nerve blocks were found to be ultrasound-guided transversus abdominis plane block with adjuvant and ultrasound-guided quadratus lumborum block. Conclusions: These results provide robust evidence for the routine use of regional techniques in combination with nonopioid analgesics in perioperative pain management. However, further better quality and larger trials are needed, considering the low confidence levels for certain interventions.