Efficacy and safety of multimodal opioid-sparing anesthesia in adult abdominal surgery patients: a systematic review and meta-analysis

Abstract

Background.Opioid analgesics are an integral component of perioperative pain management; however, their use is associated with adverse events such as postoperative nausea and vomiting, sedation, respiratory depression, ileus, and delayed recovery. Multimodal low-dose opioid strategies are considered a means of reducing the opioid burden while maintaining adequate analgesia in patients undergoing abdominal surgery. Objective.To evaluate the efficacy and safety of multimodal low-dose opioid anesthesia and analgesia by comparing it with standard opioid-based, placebo-controlled, or alternative perioperative management strategies in adult patients in abdominal surgery. Eligibility criteria.Randomized, quasi-randomized, and comparative observational studies involving adult patients aged ≥18 years undergoing open, laparoscopic, robot-assisted, elective, or emergency abdominal surgery were included. Studies without a comparison group, case series, reviews, preprints, conference abstracts without sufficient data, preclinical studies, and publications lacking relevant clinical outcomes were excluded. Evidence sources.A literature search was performed in PubMed/MEDLINE, ScienceDirect, SpringerLink, eLibrary, CyberLeninka, and Google Scholar for the period 2000–2026. The last search was conducted on April 6, 2026. No language restrictions were applied. Data extraction methods.Study selection, data extraction, and risk-of-bias assessment were performed by two authors independently; disagreements were resolved through discussion and consensus or by consulting a third author. The Cochrane Risk of Bias 2 tool was used to assess the risk of bias in randomized trials, and the Newcastle–Ottawa Scale was applied for non-randomized comparative studies. Meta-analysis was conducted using the DerSimonian–Laird random-effects model. For continuous outcomes, the mean difference or standardized mean difference was calculated; for dichotomous outcomes, the relative risk was estimated. Results.Of 10,871 records actually screened, 23 studies were included in the review, comprising 21 randomized and 2 non-randomized comparative studies. The incidence of postoperative nausea was lower with the multimodal low-dose opioid strategy: RR = 0.514; 95% CI 0.312–0.848; p = 0.009; I² = 0%. No statistically significant difference was found for the vomiting outcome: RR = 0.799; 95% CI 0.485–1.316; p = 0.379; I² = 0%. The length of stay in the post-anesthesia care unit also did not differ between the groups: SMD = 0.048; 95% CI −0.175 to 0.270; p = 0.674; I² = 0%. Exploratory analysis demonstrated a reduction in the need for rescue analgesia, intraoperative sufentanil dose, and time to first defecation as an indicator of accelerated recovery of bowel function; however, these findings exhibited high heterogeneity. Formal asymmetry tests were not performed due to the small number of studies for each identified outcome. Conclusion.Multimodal low-dose opioid strategies in adult patients undergoing abdominal surgery may reduce the incidence of postoperative nausea without compromising other parameters. Data on the reduction in rescue analgesia requirements, intraoperative opioid consumption, and accelerated recovery of bowel function are promising but warrant cautious interpretation and confirmation in more homogeneous multicenter studies.