Postsurgical Outcomes in Veterans with Advanced CKD vs. ESKD on Chronic Dialysis

Background: Patients with advanced chronic kidney disease (CKD) have poor post-surgical outcomes, perhaps due in part to negative uremic impacts on immune function, hemostasis, and wound healing. We hypothesized that end stage kidney disease (ESKD) patients on chronic dialysis would have better post-surgical outcomes due to reduced uremic toxin burden compared to patients with advanced CKD, particularly for post-surgical infection and bleeding. We compared outcomes following surgery between patients with advanced CKD not on chronic dialysis to patients with ESKD on chronic dialysis within the Veterans Affairs Health Care System. Methods: We analyzed data from the VA Surgical Quality Improvement Program (VASQIP) database from 2013 to 2019. Veterans with an eGFR <20 mL/min based on pre-operative creatinine or ESKD on chronic dialysis were included. Exclusion criteria were emergent surgery, pre-operative acute kidney injury, or pre-operative sepsis. Outcomes including mortality, infection, cardiac events, and hematologic and respiratory complications were assessed over a 30-day period from surgery. The two groups were compared using a General Estimating Equation (GEE) model that adjusted for age, comorbidities, frailty, urgent case status, and operative stress score. Results: A total of 3,097 patients were included, of which 643 had CKD with eGFR <20 mL/min and 2,454 had ESKD. The ESKD patients were younger but had higher frailty and comorbidity scores. After adjustments, CKD patients had 56% increased odds of having a post-surgical complication (Table). Conclusion: Veterans with advanced CKD had higher rates of post-surgical complications than Veterans with ESKD on chronic dialysis, particularly cardiac and infectious complications. It is possible that uremic burden may contribute to poor post-surgical outcomes in advanced CKD, though additional research is needed to further understand this association. - Outcome (CKD vs ESKD) Adjusted Odds Ratio 95% Confidence Interval P-value 30-Day Mortality 1.22 0.74 - 2.03 0.4 30-day Readmission 0.91 0.72 – 1.14 0.4 Any Post-Surgical Complication 1.56 1.23 – 1.97 0.0003 Adverse Cardiac Events 1.67 1.09 – 2.55 0.02 Post-Surgical Infections 1.37 1.00 – 1.86 0.048 Hematologic Complications 0.81 0.27 – 2.40 0.7 Respiratory Complications 0.99 0.58 – 1.70 0.9