This is a prospective, randomized, sham-controlled, superiority trial that aimed to investigate the efficacy of electroacupuncture (EA) in reducing the duration of postoperative ileus and hospital stay after laparoscopic total mesorectal excision or abdominoperineal resection for rectal cancer.

Background: Postoperative ileus (POI) remains a significant problem after colorectal surgery that adversely influences patients' recovery and prolongs hospital stay. The investigators' previous study demonstrated that electroacupuncture (EA) at Zusanli, Sanyinjiao, Hegu, and Zhigou reduces the duration of POI and hospital stay after laparoscopic resection of colonic and upper rectal cancer (Ng et al. Gastroenterology 2013; 144: 307-313). However, patients with mid/low rectal cancer undergoing laparoscopic sphincter-preserving total mesorectal excision (TME) or abdominoperineal resection (APR) were excluded. These complicated cases are apparently more likely to develop prolonged ileus and morbidity after surgery.

Objectives: To investigate the efficacy of EA in reducing the duration of POI and hospital stay after laparoscopic TME or APR for rectal cancer.

Hypothesis: Rectal cancer patients undergoing laparoscopic TME or APR within a fast-track perioperative program who receive EA will have shorter duration of POI and hospital stay when compared with those who receive sham acupuncture (SA).

Design: Prospective, randomized, sham-controlled, superiority trial.

Subjects: One hundred and sixty four consecutive patients with mid/low rectal cancer undergoing laparoscopic surgery without the need of conversion will be recruited. All patients will follow a standard perioperative fast-track program.

Interventions: Patients will be randomly allocated to receive either EA or SA. Bilateral acupoints including Zusanli, Sanyinjiao, Hegu, and Zhigou will be used. The acupuncturist is the only individual who is aware of the treatment allocation; the patients randomized to the EA/SA groups and the outcome assessor are blinded to the treatment allocation. The patients will undergo one session of EA daily from day 1 till day 4, or until the time when the primary outcome has occurred, whichever is earlier.

Outcome measures: Primary outcome: a composite endpoint of time to recovery of upper and lower gastrointestinal function (GI-2). Secondary outcomes: time to discharge order written, length of hospital stay, postoperative pain scores and analgesic requirement, and postoperative 30-day morbidity.

Inclusion Criteria:

• Consecutive patients (aged between 18 and 80) with mid/low rectal cancer (adenocarcinoma in the rectum of which the lowest margin of the tumor is located within 12 cm of the anal verge as measured by rigid sigmoidoscopy) undergoing laparoscopic sphincter-preserving TME or APR without the need of conversion
• American Society of Anesthesiologists grading I-III
• Informed consent available

Exclusion Criteria:

• Patients with previous experience of acupuncture
• Those undergoing simultaneous laparoscopic resection of rectal cancer and other coexisting intraabdominal diseases
• Those undergoing laparoscopic resection of rectal cancer with en bloc resection of surrounding organs
• Those who developed intraoperative problems or complications (e.g. bleeding, tumor perforation) that required conversion
• Those undergoing emergency surgery
• Those with previous history of midline laparotomy
• Those with evidence of peritoneal carcinomatosis
• Those who are expected to receive epidural anesthesia or analgesia
• Those with cardiac pacemaker
• Those who are pregnant
• Those who are allergic to the acupuncture needles

The acupuncturist is the only individual who is aware of the treatment allocation; the patients randomized to the EA/SA groups and the outcome assessor are blinded to the treatment allocation.