Efficacy and safety of transcutaneous electrical acupoint stimulation to assist bowel cleansing: study protocol for a single-center, single-blind, randomized controlled trial

Introduction High-quality bowel preparation is a crucial prerequisite for ensuring the effectiveness of colonoscopy. Although polyethylene glycol (PEG) remains the first-line cleansing regimen recommended by clinical guidelines, its practical application still faces challenges in achieving adequate bowel preparation rates. Transcutaneous electrical acupoint stimulation (TEAS) shows promise in enhancing intestinal motility through gut-brain-microbiota modulation. However, its role in the field of intestinal cleansing remains unclear. Methods and analysis This randomized controlled trial will enroll 404 patients undergoing elective colonoscopy. The participants will be randomly allocated to either the TEAS group or the sham-TEAS group, in a 1:1 ratio. TEAS was applied to stimulate the Zusanli (ST36) and Neiguan (PC6) acupoints using a clinically validated stimulation mode, administered concomitantly with PEG in a combined treatment protocol. The primary outcome measure was the rate of adequate bowel preparation, evaluated with the Boston Bowel Preparation Scale (BBPS). Secondary endpoints encompass colonoscope insertion and withdrawal times, cecal intubation rate (CIR), adenoma detection rate (ADR), first defecation time, total defecation frequency, final stool characteristics, adverse event incidence, and satisfaction. Discussion By bridging traditional acupoint therapy with quantifiable neurogastroenterological outcomes, this study aims to establish TEAS as a scalable adjunct in bowel preparation protocols. Trial registration International Traditional Medicine Clinical Trial Registry, ITMCTR2025001121. Registered on April 30, 2025, http://itmctr.ccebtcm.org.cn/ .