Efficacy and safety of electroacupuncture for postoperative bowel obstruction after abdominal surgery: A systematic review and meta-analysis

Table 1 Basic Characteristics of the included studies (n = 9)

Ref.	Country/region	Study population/surgical type	Study design	Group size	Age (year)	Sex	Main notes
Meng et al[16], 2010	China	Patients after intra-abdominal surgery for colon cancer	Randomized controlled trial	EA group 44; conventional control group 41	Overall mean age 537; EA group 54.3; control group 53.1	Overall: 47 males, 38 females	Aimed at prevention of PPOI
Ng et al[20], 2013	Hong Kong (China)	Patients undergoing laparoscopic resection for colon cancer and upper rectal cancer	Prospective randomized three-arm trial	EA 55; Sham 55; No acupuncture 55	67.4 ± 9.7; 67.4 ± 10.7; 68.5 ± 10.6	Male/female: 35/20; 33/22; 31/24	Single-center study registered at ClinicalTrials.gov
Zhang et al[17], 2014	China	Patients undergoing elective open resection for malignant colorectal tumors	Randomized sham-controlled trial	EA 19; Sham EA 20	63 ± 9 vs 60 ± 10	Male/female: 11/8 vs 11/9	Thirty-nine patients completed the study; ST36 EA
Chen et al[21], 2024	China	Patients with clearly diagnosed POI after colorectal cancer surgery	Two-group controlled study using random number table	Treatment group 30; control group 30	63.53 ± 14.39 vs 61.83 ± 11.90	Male/female: 17/13 vs 15/15	Therapeutic study of postoperative POI
Yang et al[22], 2022	China	Patients after elective laparoscopic colorectal resection	Single-center, three-arm, prospective randomized trial	ST25-EA 35; ST36-EA 35; standard care 35	61.8 ± 11.0; 60.7 ± 12.7; 60.7 ± 10.5	Male/female: 18/17; 25/10; 23/12	Time to first flatus and first defecation as co-primary outcomes
Qiu et al[23], 2021	China	Patients with ileus after open surgery for gastrointestinal malignancies	Randomized controlled trial	EA group 45; conventional treatment group 45	Both groups approximately 57 (57 ± 12 vs 57 ± 14)	Male/female: 26/19 vs 19/26	Post-open-surgery gastrointestinal malignancy population
Wang et al[24], 2023	China	Patients after laparoscopic colorectal cancer resection	Multicenter, randomized, sham-controlled clinical trial	EA 125; Sham EA 123	60.2 ± 11.0 vs 60.2 ± 11.8	Male/female: 70/55 vs 83/40	Multicenter study under ERAS background
Shao et al[25], 2021	China	Patients after laparoscopic colorectal cancer surgery	Three-arm block-randomized trial	Randomized: Tianshu group 15; Zusanli group 15; conventional group 14; final analysis 12/11/13	62.9 ± 7.6; 57.3 ± 12.3; 59.0 ± 8.1	Male/female: 10/5; 10/5; 12/2	Small-sample three-arm study
Pei et al[26], 2025	China	Patients after laparoscopic gastrectomy for gastric cancer	Seven-center, three-arm, randomized trial	Randomized: EA 195; Sham 190; Standard care 195; FAS: 194/189/195	59.87 ± 9.93; 59.69 ± 10.60; 60.39 ± 10.13	Male/female: 127/68; 128/66; 134/55	Multicenter postoperative gastric cancer study

EA: Electroacupuncture; PPOI: Persistent/prolonged postoperative ileus; POI: Postoperative ileus; ERAS: Enhanced recovery after surgery.

Table 2 Summary of findings and certainty of evidence for main outcomes

Outcome	Number (studies)	Effect estimate	Certainty	Reasons for downgrading
Time to first flatus	1396 (9)	MD = -10.91 hours (95%CI: -15.07 to -6.74)	Low	Risk of bias; inconsistency
Time to first defecation	1397 (9)	MD = -19.80 hours (95%CI: -28.60 to -11.01)	Low	Risk of bias; serious inconsistency
Length of stay	495 (6)	MD = -0.93 days (95%CI: -1.67 to -0.18)	Low	Inconsistency; indirectness
Prolonged/persistent postoperative ileus	1067 (4)	OR = 0.45 (95%CI: 0.33-0.60)	Moderate	Risk of bias
Time to ambulation/independent walking	884 (4)	MD = -9.37 hours (95%CI: -18.34 to -0.40)	Very low	Inconsistency; indirectness; imprecision
Safety/adverse events	Not pooled	Mild adverse events reported; no definite serious adverse events described	Very low	Risk of bias; indirectness; very serious imprecision due to incomplete safety reporting

MD: Mean difference; OR: Odds ratio; 95%CI: 95% confidence interval.