Assessing fluid balance in critically ill pediatric patients

Area of Science:

• Pediatric critical care medicine
• Clinical fluid balance monitoring
• Intensive care unit research

Background:

• Accurate fluid balance (FB) monitoring is vital in pediatric intensive care units (PICUs) to manage fluid overload.
• Pediatric intensivists commonly use fluid intake minus output (FIMO) or adjusted FIMO (AFIMO) for FB assessment.
• The clinical accuracy of FIMO/AFIMO in critically ill children remains untested.

Purpose of the Study:

• To prospectively evaluate the accuracy of FIMO and AFIMO compared to body weight changes (BWC) in critically ill children.
• To assess the time burden and convenience of FIMO/AFIMO calculations versus BW measurements.

Main Methods:

• A prospective, monocentric cohort study included 60 consecutive pediatric patients admitted to a PICU.
• Body weight was measured at admission and 24 hours later; FIMO/AFIMO were calculated every 12 hours.
• Statistical analysis included linear regression (r²), Bland-Altman plots, and Wilcoxon tests for time/convenience.

Main Results:

• Strong correlations were found between FIMO/AFIMO and BWC (r²=0.63-0.72, p<0.0001).
• However, agreement was poor, with variations exceeding 300 mL (FIMO: 0.382 L, AFIMO: 0.302 L).
• No significant differences in time burden or convenience were observed between methods.

Conclusions:

• FIMO/AFIMO demonstrate poor agreement with BWC within the initial 24 hours of PICU admission.
• Pediatric intensivists should consider using FIMO/AFIMO primarily for patients with contraindications to body weight measurements.