Incidence and perioperative risk factors for early acute kidney injury after radical cystectomy and urinary diversion.

BACKGROUND: Early postoperative acute kidney injury (AKI) is associated with increased morbidity and mortality following major surgery. Only few reports exist on postoperative AKI and specifically its risk factors after radical cystectomy (RC) and urinary diversion (UD). We aimed to identify risk factors for AKI in patients undergoing RC and UD.

METHODS: In an observational single-center cohort study, 912 consecutive bladder cancer patients undergoing RC and UD from 2000 to 2016 were evaluated for risk factors for AKI. Multiple logistic regression analysis was performed to model the association between variables and AKI.

RESULTS: Early postoperative AKI occurred in 100/912 patients (11%). An increased risk was seen in patients with surgery lasting>400minutes, male and obese patients (>25kg/m²). Independent predictors were duration of surgery (P = 0.020), intraoperative blood loss (P = 0.049), preoperative serum creatinine values (P = 0.004), intraoperative administration of crystalloids (P = 0.032), body mass index (P = 0.031), and fluid balance (P = 0.006). Patients with AKI had a longer hospitalization time (18d vs 17d, P = 0.040). Limitations include the potential bias due to the design as a case series with prospectively collected data with some missing values.

CONCLUSIONS: An increased risk for AKI was seen in patients with an operative time>400 minutes. Hence, in this group of patients the role of postoperative fluid management for preserving renal function should be considered. Further independent predictors of postoperative AKI were male sex, obesity, intraoperative blood loss, and a low preoperative plasma creatinine. So specially in male and obese patients, optimized perioperative nephroprotective strategies are of importance.