Incidence and risk factors for acute kidney injury after radical cystectomy

Objectives: To clarify the incidence, risk factors and clinical impact of acute kidney injury after radical cystectomy. Methods: A total of 210 patients who underwent radical cystectomy at Sapporo Medical University Hospital, Sapporo, Japan, from January 2006 through December 2012 were evaluated. The incidence of acute kidney injury was evaluated over the first 7 days postoperatively, during which time a ureteral catheter was inserted. Risk factors for postoperative acute kidney injury and its impacts on short-term clinical outcomes were evaluated. Results: Finally, 145 patients were eligible for this study. Postoperative acute kidney injury was observed in 48 patients (33.1%), with stages 1, 2, and 3 found in 33 (22.7%), 14 (9.6%) and 1 (0.7%), respectively. All patients with stage 1 and 2 acute kidney injury recovered by postoperative day 7, except for one with stage 1. Hypertension (P < 0.001), preoperative estimated glomerular filtration rate <60 mL/min/1.73 m² (P = 0.04) and neoadjuvant chemotherapy (P = 0.03) were independent risk factors for postoperative acute kidney injury. Furthermore, postoperative acute kidney injury was an independent risk factor for acute kidney injury after ureteral stent removal, but not of persistent elevated serum creatinine, prolonged hospital stay or the new onset of cardiovascular disorders during the hospital stay. Conclusions: The incidence of acute kidney injury after radical cystectomy is relatively high, although most cases are low grade and can be resolved. We should be aware of the risk for postoperative acute kidney injury, especially in patients who have comorbid hypertension, impaired renal function and received naoadjuvant chemotherapy.