Systematic review and meta-analysis of acupuncture for postoperative gastrointestinal dysfunction after colorectal cancer surgery

Table 1 Characteristics of included studies

Ref.	Country/region	Sample size (intervention/control)	Surgical procedure	Study design	Intervention	Control	Outcomes reported
Meng et al[15], 2010	China	44/41	Open intraperitoneal surgery for colon cancer	RCT	Electroacupuncture (SJ-6, GB-34, ST-36, ST-37; postoperative days 1-6; 2 Hz)	Usual care	1, 2
Ng et al[8], 2013	Hong Kong, China	55/55	Laparoscopic colorectal resection (colonic and upper rectal cancer)	RCT	Electroacupuncture (ST36, SP6, LI4, TE6; postoperative days 1-4; 100 Hz)	Sham acupuncture (superficial needling at non-acupoints, no electrical stimulation)	1, 2, 3
Gao et al[16], 2021	China	303/307	Laparoscopic or open colorectal surgery	RCT	TEAS (ST36, ST37, SP6; PACU + postoperative days 1-3; 2/10 Hz)	Sham stimulation (electrodes at same acupoints, no current)	1, 2, 4, 6, 8
Lu et al[17], 2022	China	47/47	Laparoscopic colon surgery	RCT	TEAS (PC6, LI4, ST36, SP6; 30 minutes before surgery + 3 days postoperatively; 2/10 Hz)	Usual care	1, 2, 3, 5
Yang et al[19], 2022	China	35/35	Laparoscopic elective colorectal resection	RCT	Electroacupuncture (single acupoint ST36; postoperative days 1-4; 2/100 Hz)	Usual care	1, 2
Wang et al[7], 2023	China	125/123	Laparoscopic colorectal resection	RCT	Electroacupuncture (RN12, ST25, ST36, ST37; postoperative days 1-4; 2/100 Hz)	Sham electroacupuncture (superficial needling at non-acupoints, no electrical stimulation)	1, 2, 3
Li et al[18], 2025	China	33/32	Laparoscopic colorectal resection	RCT	TEAS (LI4, PC6, ST36, ST37, ST39, SP6; 1 day before surgery + pre-induction + skin incision + end of surgery + postoperative days 1-3; 2/10 Hz)	Sham stimulation (electrodes at same acupoints, no current)	1, 2, 5, 6, 7
Yin et al[14], 2026	China	40/43	Laparoscopic colorectal resection	RCT	Thumb-tack needle (ST36; retained for 3 days postoperatively)	Sham thumb-tack needle (adhesive tape only)	1, 2, 5, 8

Sample sizes shown are the actual numbers included in the metaanalysis for each comparison. Of note, Ng et al[8], 2013 and Yang et al[19], 2022 were three-arm randomised controlled trials; this Table 1 only extracted the specific comparisons that met our inclusion criteria (electroacupuncture vs sham acupuncture for Ng et al[8], 2013; electroacupuncture at ST36 vs standard care for Yang et al[19], 2022). The third arms were not included in the Table 1 or in the total sample size. Therefore, the overall sample size for this metaanalysis is the sum of all patients listed in this Table 1 (1365 in total). 1: Time to first flatus; 2: Time to first defecation; 3: Length of hospital stay; 4: Time to first bowel sounds; 5: Time to first liquid/semiliquid diet; 6: Incidence of postoperative nausea and vomiting; 7: Incidence of postoperative abdominal distension; 8: Serum inflammatory markers (interleukin-6, tumor necrosis factor-α). RCT: Randomised controlled trial; TEAS: Transcutaneous electrical acupoint stimulation; PACU: Post-anesthesia care unit.