Supplementary Material for: Initiation of Renal Replacement Therapy in the Intensive Care Unit in Vicenza (IRRIV) Score

Introduction: One of the top research priorities in acute kidney injury is related to the timing of renal replacement therapy (RRT) initiation. The purpose was to develop an index that might serve as a standardized concept of timing of initiation of RRT. Methods: A previously described database was used. We applied a multivariable Cox regression model with backward selection to characterize parameters present in those patients who received RRT compared with those who did not receive RRT. Results: We studied 590 patients. We identified independent risk factors for RRT and a risk score was devised. The Area Under the Curve of the receiver operating characteristic curve was 0.81 (95% CI 0.74-0.86) for predicting the need for RRT. Conclusions: We have developed a simple Score (IRRIV Score) to identify patients at high risk of requiring RRT. This score may serve as a standardized definition of the timing of initiation of RRT.