Clinical impact and safety of continuous renal replacement therapy in critically ill patients with solid tumors and acute kidney injury: a retrospective cohort analysis.

Objectives: To evaluate the efficacy and safety of continuous renal replacement therapy (CRRT) in critically ill patients with solid tumors complicated by acute kidney injury (AKI) in the intensive care unit (ICU).

Methods: In this retrospective cohort study, 580 ICU patients with solid tumors and AKI were enrolled and stratified into a CRRT group (n = 300) and a non-CRRT group (n = 280). CRRT was initiated within 12 hours of ICU admission in patients meeting Kidney Disease Improving Global Outcomes stage 3 criteria. Propensity score matching (PSM) was performed to balance baseline characteristics. Primary outcomes included AKI remission, metabolic stabilization, and 90-day survival. Multivariable logistic regression and XGBoost machine learning were used to identify prognostic factors and build predictive models.

Results: After PSM, baseline characteristics were well balanced. CRRT significantly improved renal and metabolic parameters within 72 hours, including reductions in serum creatinine, blood urea nitrogen, and lactate (all P < 0.001), with a trend toward increased urine output. The CRRT group had higher AKI remission (64.54% vs. 49.65%, P < 0.001) and 90-day survival rates (47.52% vs. 39.01%, P = 0.012), albeit with greater dialysis dependence (19.15% vs. 0.00%, P < 0.001). Adverse events were comparable. XGBoost models achieved AUCs of 0.78 and 0.75 for mortality and AKI remission, respectively.

Conclusions: CRRT improves renal recovery, metabolic status, and survival in critically ill cancer patients with AKI, with an acceptable safety profile. Machine learning offers promising tools for individualized outcome prediction.