Haemodynamic Transition after Birth: A New Tool for Non-Invasive Cardiac Output Monitoring

Substantial haemodynamic changes occur during the first minutes after birth. Currently, only heart rate (HR) and arterial oxygen saturation are routinely used to monitor haemodynamic transition after birth.

The aim of the present study was to continuously assess haemodynamic changes during transition in term infants for the first time by using electrical velocimetry (EV), a new method of non-invasive cardiac output monitoring (NICOM), based on impedance cardiography technology.

In this prospective observational study, term neonates delivered by elective caesarean section underwent NICOM measurements within the first 15 min after birth. The beat-to-beat measurement over a 10-second period was used to calculate cardiac output (CO) for each minute after birth. The data of CO were only accepted when the signal quality index (SQI) remained >80% during the measurement period of 10 s.

100 term neonates underwent 1,500 NICOM measurements. 1,143 (76.2%) measurements were excluded because of a SQI <80%. HR and CO showed a trend to increase within the first minutes, and decreased significantly from minute 3 (HR) and 4 (CO), until minute 12 and 10, respectively. Stroke volume remained stable during the observation period.

The present study was the first using EV for NICOM during the transition period in a larger cohort of newborn infants. Results of NICOM were similar to available echocardiography data. The possibility of NICOM offers continuous CO measurement. The present study supports the idea that CO is closely related to HR in newborn infants.