Development and Validation of an Electronic Fluid Balance Calculator for Critically Ill Children.

Our objective was to describe and validate the performance of a real-time cumulative fluid balance (CFB) calculator built into the electronic health record (EHR). We performed a retrospective cohort study in the cardiac and general medical-surgical pediatric ICUs of a single center and included all encounters between June-November 2025. Our outcome of interest was the daily calculated difference between the real-time %CFB calculator and a documented %CFB (from retrospective de-identified data extracted from the EHR) from the first fourteen ICU days. We calculated the number (%) of encounters whose difference varied by > 0.1%CFB and assessed correlation using Pearson correlation coefficients. We collected 468 unique hospital encounters spanning 154 days, making up 2041 ICU patient-days. The real-time %CFB calculator matched the documented %CFB within < 0.1% CFB on 1971 (96.6%) days. There were 34 encounters, 20 pediatric cardiac ICU and 14 pediatric medical/surgical ICU, whose difference was > 0.1%, correlation (R2) > 0.99. In conclusion, we developed a real-time %CFB calculator within the EHR and validated its accuracy in an attempt to provide evidence of its reliability for clinical use. A %CFB calculator that indexes net fluid balance to weight and is readily available may bring greater attention to clinical fluid overload.