New-onset renal impairment following radical nephrectomy for renal cell carcinoma: a retrospective cohort study of clinical, intraoperative, and postoperative risk factors

Background: Radical nephrectomy is a recommended treatment for localized renal cell carcinoma when partial nephrectomy is not feasible. This approach is typically applied to patients with a normal contralateral kidney and no preexisting chronic kidney disease (CKD). The primary concern with surgery is its potential long-term impact on renal function. Objectives: To assess the risk of development of chronic kidney disease after radical nephrectomy. Design and methods: This is a retrospective cohort study of patients with normal preoperative renal function and contralateral kidney who underwent radical nephrectomy for cancer. At the last follow-up, patients were categorized according to CKD-EPI guidelines as having normal renal function grades G1-2 or impaired renal function grade ⩾G3a. Univariable and multivariable Cox regression analyses were used to identify the significant risk factors for CKD-free survival. Results: We included 135 patients, 49.1 SD 12.9 years old, 62 women (45.9%), and 73 men (54.1%). Preoperative weight was 81 SD 18 kg, and eGFR was 99.2 SD 19.2 mL/min/1.73 m 2 . The last follow-up 32.8 SD 16.8 months later showed that 38 (28.1%) patients developed renal impairment. Univariable analysis showed that preoperatively age in years, age ⩾65, male gender, hypertension, Charlson Comorbidity score, cerebrovascular disease, low preoperative eGFR, serum creatinine, and baseline CKD EPI grade G2 were significant predictors of last follow-up renal impairment. Intraoperatively, anesthesia duration, surgery duration, and postoperatively, within the first 48 hours lower eGFR, creatinine, and CKD-EPI category G3-5 were significant risk factors predicting CKD. After exclusion of colinear risk factors, multivariable analysis, however, indicated that preoperative eGFR ( p < 0.027), lower intraoperative nadir MAP ( p = 0.006), and postoperative within 48-hour eGFR ( p = 0.003) were independent predictors of CKD-free survival at the last follow-up. Conclusion: Significant risk factors for renal impairment after radical nephrectomy were a decreased preoperative eGFR, intraoperative hypotension and, within 48h, postoperative eGFR. No other preoperative or intraoperative risk factor independently predicted CKD.