Systematic review: The role of bicarbonate therapy after urinary diversion.

Background: Radical cystectomy (RC) with urinary diversion remains the standard of care for muscle invasive bladder cancer. While metabolic acidosis (MA) after RC is common, the relationship between MA, post-operative complications, and the impact of bicarbonate supplementation remains unclear. Objective: To review the role of bicarbonate therapy for MA following RC. Methods: We performed a comprehensive systematic review according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines analyzing MA after RC. We included randomized controlled trials and cohort studies that reported metabolic acidosis complications and studies that utilized bicarbonate therapy peri-operatively. Our primary outcome was metabolic acidosis or role of metabolic acidosis as it relates to bicarbonate therapy or post-operative complications. Results: Twenty-nine studies were identified to investigate MA in the setting of postoperative complication rates or the role of bicarbonate treatment in peri-operative pathways. 19 studies evaluated the incidence of MA without intervention, 5 studies supplemented bicarbonate therapy for patients meeting specific criteria, and 5 studies utilized a standardized postoperative bicarbonate therapy regimen. The incidence of post-operative metabolic acidosis ranged from 1-86% after continent urinary diversion and 1-27% after ileal conduit urinary diversion. Post-operative renal function, diabetes, and older age were factors associated with metabolic acidosis. There was lack of uniformity, indications, or consistent outcomes for utilizing postoperative bicarbonate therapy. Conclusion: There is little uniformity regarding the role of supplemental bicarbonate therapy and its impact on post-operative complications following urinary diversion. Future studies are needed to better evaluate the role MA plays in peri-operative RC pathways.