Measurement of Cardiac Output in Children by Bioreactance

The objective of this study was to evaluate a new bioreactance method for noninvasive cardiac output (CO) measurement (NICOM) in children. Ten patients between 1 and 144 months of age and with no hemodynamic disturbances were studied. Using bioreactance, heart rate (HR), mean arterial pressure (MAP), and cardiac index (CI) measurements were made every 6–8 h. CI was 2.4 ± 1.03 l/min/1.73 m² (range 1–4.9 l/min/1.73 m²); There were significant correlations between CI and age (r = 0.50, P = 0.003), weight (r = 0.66, P < 0.001), and MAP (r = 0.369, P = 0.037). Significant differences in CI (P < 0.001) were detected between children weighing <10 kg (1.9 ± 0.73 l/min/1.73 m²; range 1–3.2), 10–20 kg (2.07 ± 0.7 l/min/1.73 m²; range 1–3.6), and >20 kg (3.7 ± 0.8 l/min/1.73 m²; range 2.4–4.9). We conclude that the CI measured by bioreactance in children varies with the age and weight of the patients and is lower than the normal range in a large percentage of measurements. These data suggest that this method is not useful for evaluating CI in small children.