Povidone-iodine vs sodium hypochlorite enema for mechanical preparation before elective open colonic or rectal resection with primary anastomosis - A multicenter randomized controlled trial

Hypothesis: The anti-infective actions of povidone-iodine (PVI) and sodium hypochlorite enemas are different. Design: Prospective, randomized, single-blind study Setting: Multicenter. Patients: Five hundred seventeen consecutive patients with colorectal carcinoma or sigmoid diverticular disease undergoing elective open colorectal resection, followed by primary anastomosis. Intervention: All patients received senna (1-2 packages diluted in a glass of water) at 6 Pm the evening before surgery. Patients were administered two 2-L aqueous enemas of 5% PVI (n=277) or 0.3% sodium hypochlorite (n=240) at 9 Pm the evening before surgery and at 3 hours before operation. Intravenous ceftriaxone sodium (1 g) and metronidazole (1 g) were administered at anesthetic induction. Main outcome Measure: Rate of patients with 1 infective parietoabdominal complication or more. Results: The percentages of patients with 1 infective parietoabdominal complication or more did not differ between the 2 groups (13.7% in the PVI-treated group vs 15.0% in the sodium hypochlorite-treated group). Tolerance was better in the PVI-treated group than in the sodium hypochlorite-treated group (79.4% vs 67.9%), with fewer patients experiencing abdominal pain (13.0% vs 24.6%) or discontinuing their preparation (3.0% vs 9.0%) (P=.02 for all). There were more patients with malaise in the PVI-treated group than in the sodium hypochlorite-treated group (9.1% vs 4.9%, P<. 05). Three patients in the sodium hypochlorite-treated group had necrotic ulcerative colitis. Conclusion: When antiseptic enemas are chosen for mechanical preparation before colorectal surgery, PVI should be preferred over sodium hypochlorite because of better tolerance and avoidance of necrotic ulcerative colitis.