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Bioelectrical impedance parameters in critically ill children: importance of reactance and resistance
Zina Maria Almeida Azevedo1, Daniella Campelo Batalha Cox Moore, Flavia Aparecida Alves de Matos
1Intensive Care Unit, Pediatrics Department, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
Insights
Bioelectrical impedance analysis (BIA) can predict outcomes in critically ill children. Low reactance (Xc/H) and resistance (R/H) values on admission indicate severe organ dysfunction, with changes over time correlating to survival.
Area of Science:
- Critical Care Medicine
- Pediatric Intensive Care
- Biomedical Engineering
Background:
- No reliable clinical parameters exist for predicting prognosis in critically ill patients.
- Raw bioelectrical impedance parameters show potential for prognostic assessment.
Purpose of the Study:
- To investigate the behavior of reactance and resistance in critically ill pediatric patients.
- To correlate bioelectrical impedance parameters with patient outcomes.
Main Methods:
- Prospective analysis of bioelectrical impedance in 332 mechanically ventilated pediatric patients.
- Measurement of reactance (Xc/H) and resistance (R/H) on admission and discharge.
- Correlation of impedance values with major clinical outcomes.
Main Results:
- Low Xc/H (<27.7 Ohm/m) and R/H (<563.6 Ohm/m) on admission associated with multiple organ dysfunction (≥4).
- Survivors showed significant increases in R/H and Xc/H from admission to discharge.
- Non-survivors exhibited a trend of decreasing R/H and Xc/H from admission to death.
Conclusions:
- Bioelectrical impedance analysis is a valuable tool for monitoring critically ill pediatric patients.
- R/H and Xc/H may serve as predictive biomarkers for septic shock and organ dysfunction, warranting further investigation.
Background & Aims:
Currently, there are no clinical or laboratory parameters that can be used efficiently to predict the prognosis of critically ill patients, but in some situations, raw bioelectrical impedance parameters have been shown to be useful. The purpose of this study was to investigate the behavior of reactance and resistance in the severity of the critically ill pediatric patient.
Methods:
We prospectively analyzed bioelectrical impedance in a sample of 332 critically ill pediatric patients submitted to mechanical ventilation. The values taken on admission and discharge were correlated with major outcomes to the critically ill patient.
Results:
We found an association of low values of Xc/H (<27.7 Ohm/m) and of R/H (<563.6 Ohm/m) on admission with multiple organs dysfunction greater or equal to 4. Both R/H and Xc/H increased significantly between admission and discharge among survivors, while among nonsurvivors there was a trend of decrease between admission and the last measurement before death.
Conclusions:
Bioelectrical impedance is a useful tool for monitoring of critically ill pediatric patients. A possible role of R/H and Xc/H, especially the latter, as a predictive biomarker of evolution for septic shock and organ dysfunction still remains to be elucidated.
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