Bioelectrical impedance phase angle and the mortality in critically ill children

Area of Science:

• Critical Care Medicine
• Pediatric Nutrition Assessment
• Bioelectrical Impedance Analysis (BIA)

Background:

• Phase angle (PhA) from BIA is a sensitive clinical nutrition marker.
• Its prognostic value in pediatric critical care is under-researched.
• This study explores PhA's association with outcomes in critically ill children.

Purpose of the Study:

• To investigate the relationship between admission PhA and PICU length of stay (LOS).
• To assess PhA as a predictor of 60-day mortality in critically ill pediatric patients.
• To establish a critical PhA cutoff value for predicting outcomes.

Main Methods:

• Bioelectrical impedance analysis (BIA) performed within 72 hours of admission for 205 pediatric patients.
• Kaplan-Meier survival analysis and multivariate Cox regression to assess 60-day mortality.
• Youden's index and ROC curves used to determine the optimal PhA cutoff value.

Main Results:

• A PhA cutoff of 3.1° was identified, with lower PhA associated with significantly higher mortality (p<0.0001).
• Patients with PhA <3.1° had longer PICU LOS (HR 1.871, p=0.000) and hospital LOS.
• PhA and PIM-2 score were independent predictors of 60-day mortality.

Conclusions:

• Low phase angle (<3.1°) in pediatric ICU patients is linked to prolonged PICU stays and increased mortality risk.
• PhA serves as a valuable prognostic indicator in critically ill children, beyond its role in nutritional assessment.
• Routine PhA measurement can aid in risk stratification and management of pediatric ICU patients.