Predicting successful continuous renal replacement therapy liberation in critically ill patients with acute kidney injury

Abstract Purpose No standardized criteria for continuous renal replacement therapy (CRRT) liberation have been established. We sought to develop and internally validate prediction models for successful CRRT liberation in critically ill patients with acute kidney injury (AKI). Materials and methods This single-center, retrospective cohort study included adult patients admitted to intensive care units (ICUs) with AKI and treated with CRRT from January 1, 2007, to May 4, 2018, at a tertiary referral hospital. The cohort was randomly divided into derivation and validation sets. The outcomes were successful CRRT liberation, defined as renal replacement therapy (RRT)-free survival within 72 h after the liberation and hospital discharge. Multivariate logistic regression models were developed and internally validated. Results Of 1135 AKI patients requiring CRRT, successful CRRT liberation and RRT-free survival at hospital discharge were observed in 228 (20%) and 395 (35%) individuals, respectively. The independent predictors included mean hourly urine output within 12 h before liberation, mean serum creatinine value within 24 h before liberation, cumulative fluid balance from ICU admission to liberation, CRRT duration before liberation, and the requirement of vasoactive agents within 24 h before liberation. The models demonstrated good discrimination (AUROC, 0.76 and 0.78; positive predictive value, 36% and 48%; negative predictive value, 92% and 94%; respectively) and calibration in the validation set. Conclusions These validated models could assist the decision-making related to the CRRT liberation in critically ill patients with AKI.