Statistics & randomization In prospective series analysed in different centres, the incidence of postoperative complications in patients underwent to emergency colonic surgery was 35%. The positioning of the stent associated to second time surgical elective treatment is characterized by 15% of morbidity (stent: 5%, surgery: 10%). The number of patients needed to carry on the study making statistically significant this difference (35% vs 15%) with an error alpha = 0.05 and beta = 0.2 and estimating a loss of 5% of the samples, is 72 patients in each group.