Trending ability of electrical cardiometry for non-invasive cardiac output monitoring in preterm neonates during the transitional period: a polar plot analysis

Electrical cardiometry (EC) enables continuous, non-invasive monitoring of cardiac output (CO) in neonates. The ability of this technique to track CO changes over time compared to transthoracic echocardiography (TTE) remains poorly studied in the neonatal population. Using polar plot analysis, we aimed to assess the trending ability of EC compared with TTE in preterm neonates during the transitional period. CO measurements were performed on preterm infants < 32 weeks' gestation and/or < 1500 g on day 1, 2 and 3 of life. Paired changes in CO (ΔCO) between consecutive days of life were calculated for both EC and TTE and used for polar plot analysis. Overall, 55 paired ΔCO measurements were available for day 1-2 and 45 for day 2-3. After excluding changes < 20% of the mean absolute ΔCO value, 46 and 41 pairs were included in the polar analysis. EC demonstrated good trending performance, with 87% and 88% of points falling within ± 30° for day 1-2 and day 2-3, respectively. The mean angular bias was 0.6° (95% CI - 5.7° to 6.8°) for days 1-2 and - 7.2° (95% CI - 16.4° to 2.0°) for days 2-3, indicating minimal systematic directional disagreement between methods. CONCLUSION: Our findings suggest a good trend tracking performance of EC for non-invasive CO monitoring during the transitional period in preterm neonates, supporting its potential role as a continuous monitoring tool for neonatal hemodynamic assessment. WHAT IS KNOWN: • Electrical cardiometry (EC) allows continuous, non-invasive cardiac output (CO) monitoring in neonates. • While EC accuracy for CO assessment has been previously investigated, little is known on its trending ability. WHAT IS NEW: • EC showed good ability to track CO changes in preterm neonates when compared to transthoracic echocardiography. • Over 85% of paired ΔCO were within ±30°, with minimal angular bias.