A retrospective analysis of 130 cases of cystectomy and urinary diversion for bladder carcinoma was performed. A logistic regression analysis found preoperative irradiation to be associated with early complications (p = 0.014), whereas no such association was observed with late complications. Metabolic evaluation in 51 surviving patients revealed hyperchloremia in 17 patients (33%) and hyperchloremic acidosis in 2 cases (4%). Vitamin B12 deficiency was found in 11 patients (22%), all of whom had preoperative irradiation or reservoir procedures performed. Routine evaluation of vitamin B12 serum levels should be carried out at follow-up in these groups of patients.