Pediatric Critical Care Fellow Children's Hospital of Philadelphia The Children's Hospital of Philadelphia Philadelphia, Pennsylvania, United States
Background: Acute kidney injury (AKI) is a common complication of critical illness and associated with high morbidity and mortality. Optimal timing of CRRT for treatment of AKI and fluid overload (FO) is unknown.
Objective: We aimed to identify risk factors for mortality in critically ill children requiring CRRT and measure the association between timing of CRRT initiation and mortality in a large, multi-center population. We hypothesized that a longer duration between intensive care unit (ICU) admission and CRRT initiation is an independent risk factor for mortality.
Design/Methods: Multi-center retrospective cohort study of children admitted to PICUs that participate in the Virtual PICU (VPS LLC) registry receiving CRRT for AKI or FO from 2012-2018. Patients with chronic kidney disease and those receiving CRRT prior to or 30 days after ICU admission were excluded. The primary exposure, time to CRRT initiation, was measured from ICU admission and analyzed as a continuous and categorical variable. Primary outcome was ICU mortality. Multivariable logistic regression with exchangeable working covariance structure and propensity score matching to balance characteristics between patients who received early vs late CRRT were performed to determine adjusted differences in mortality.
Results: ICU mortality was 34.5% (461/1334). Median time from ICU admission to CRRT initiation was 1.4 days in survivors and 3.0 days in non-survivors (p<0.001).In multivariable analysis, increased time to CRRT initiation was independently associated with mortality [OR 1.06 per day (95% CI 1.03-1.09), p<0.001]. Longer duration from ICU admission to CRRT initiation was associated with higher odds of mortality in ascending time quartiles. Compared with patients receiving CRRT <5 days, those receiving CRRT >5 days after ICU admission had higher mortality (55% vs 29%, p <0.001), longer ICU length of stay (28 vs 12 d, p<0.001), longer CRRT duration (8 vs 5 d, p<0.001) and longer time from CRRT start to ICU discharge (15 vs 10 d, p<0.001). CRRT initiation >5 days was independently associated with death after adjustment for covariates [adjusted OR 1.79 (95% CI 1.3-2.46), p=0.004] and after propensity score matching [adjusted OR 1.83 (95% CI 1.25-2.66), p=0.002]. Conclusion(s): Longer time to initiation of CRRT after ICU admission is independently associated with mortality. Consideration of early CRRT in this high-risk population may be a strategy to reduce mortality and improve recovery of renal function, and warrants further study.
Association between timing of CRRT initiation from ICU admission and ICU mortality among various time intervals
Authors/Institutions: Maureen Banigan, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States; Bingqing Zhang, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States; Julie Fitzgerald, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States
