Background Evaluation of cardiac output in neonates might be difficult because of the complexity and risks of invasive classical procedures. New systems like electrical cardiometry (EC: Osypka Medical, Berlin, Germany and La Jolla, California, USA) have been proposed but few data are available in neonates. We investigated stroke volume (SV) using EC in term and preterm infants.
Methods Eligible patients were neonates admitted to the NICU and undergoing echocardiography for any clinical reasons, without congenital heart disease. We measured SV with EC and echocardiography, within 10 min. Measurements were repeated 6 times by the same operator to calculate repeatability before and after echocardiography. Data have been compared with correlation and Bland-Altman analysis.
Results 59 neonates were enrolled, allowing 150 paired measurements. Mean gestational age and birth weight were 33.9 ± 3.4 wks and 1988 ± 823 g, respectively.
Results of Pearson correlation and Bland-Altman analysis for the whole population were (r = 0.611; p < 0.001) and (mean error [echo-EC] -1.35 mL [95% CI: -6.55 mL ± 3.85 ml]), respectively.
Correlation is maintained even with PDA (r = 0.627; p < 0.001).
Gestational age seems to do not influence the correlation between EC and echo (Partial correlation coefficient r = 0.36; p < 0.0001).
Repeatability (coefficient of variation) was 46% for EC and 52% for echocardiography. There was no difference in SV measured by EC after 10 min (3.76 ± SD vs 3.78 ± SD; p = 0.56, Wilcoxon test).
Conclusions EC is feasible, reproducible and quick. It could be an useful tool for continuous monitoring and haemodynamic evaluation in neonates. EC is particularly interesting for the clinical management of preterm neonates.