EXPRESS: Transcutaneous Electrical Acupoint Stimulation for Postoperative Gastrointestinal Recovery: A Systematic Review and Meta-Analysis Using a Composite Stimulation-Pattern Framework

BACKGROUND & AIMS: Transcutaneous electrical acupoint stimulation (TEAS) promotes postoperative gastrointestinal recovery. However, existing protocols lack standardization due to unaddressed methodological collinearity between frequency and waveform in previous analyses. We aimed to evaluate the efficacy of TEAS following abdominal surgery and examine whether treatment effects varied across stimulation parameters. METHODS: We searched four major databases from inception to April 2026 for randomized controlled trials (RCTs) comparing TEAS with sham/standard care. Frequency and waveform were systematically reconstructed into a composite "Stimulation Pattern" (Intermittent/Fixed vs. Dilatational/Alternating). Data were pooled using a random-effects model. RESULTS: Twenty RCTs comprising 2,615 patients were included. TEAS significantly accelerated the time to first flatus (MD = -9.08 h, P < 0.0001) and first defecation (MD = -16.48 h, P < 0.0001), and reduced the incidence of strictly defined POI (3 trials; RR = 0.78, 95% CI 0.64-0.96; P = 0.0214). TEAS also shortened hospital stay and mitigated postoperative nausea, vomiting, and pain. The intermittent/fixed stimulation pattern was associated with a greater reduction in time to first flatus than the dilatational/alternating pattern (interaction P = 0.0008). Adverse events were minimal (0%-1.8%). CONCLUSIONS: TEAS safely accelerates gastrointestinal motility recovery. While an optimal protocol remains to be established, the intermittent/fixed stimulation pattern appears to be a promising candidate configuration. Longer or more frequent treatment did not show clear additional benefit, supporting evaluation of a 30-min once-daily regimen as a pragmatic, resource-efficient strategy in future prospective trials.