Senna vs polyethylene glycol for mechanical preparation the evening before elective colonic or rectal resection: a multicenter controlled trial. French Association for Surgical Research.

HYPOTHESIS: Senna is more efficient than polyethylene glycol as mechanical preparation before elective colorectal surgery. DESIGN: Prospective, randomized, single-blind study. SETTING: Multicenter study (18 centers). PATIENTS: Five hundred twenty-three consecutive patients with colonic or rectal carcinoma or sigmoid diverticular disease, undergoing elective colonic or rectal resection followed by immediate anastomosis. INTERVENTION: Two hundred sixty-two patients were randomly allotted to receive senna (1 package diluted in a glass of water) and 261 to receive polyethylene glycol (2 packages diluted in 2-3 L of water), administered the evening before surgery. All patients received 5% povidone iodine antiseptic enemas (2 L) the evening and the morning before surgery. Ceftriaxone sodium and metronidazole were given intravenously at anesthetic induction. MAIN OUTCOME MEASURES: Degree of colonic and rectal cleanliness. RESULTS: Colonic cleanliness was better (P=.006), fecal matter in the colonic lumen was less fluid (P=.001), and the risk for moderate or large intraoperative fecal soiling was lower (P=.11) with senna. Overall, clinical tolerance did not differ significantly between groups, but 20 patients receiving polyethylene glycol (vs 16 with senna) had to interrupt their preparation, and 15 patients (vs 8 with senna) complained of abdominal distension. Senna, however, was better tolerated (P = .03) in the presence of stenosis. There was no statistically significant difference found in the number of patients with postoperative infective complications (14.7% vs 17.7%) or anastomotic leakage (5.3% vs 5.7%) with senna and polyethylene glycol, respectively. CONCLUSION: Mechanical preparation before colonic or rectal resection with senna is better and easier than with polyethylene glycol and should be proposed in patients undergoing colonic or rectal resection, especially patients with stenosis.