Agreement between Echocardiography-Measured Cardiac Output and Non-Invasive Cardiac Output Monitoring (NICOM) in Primagravid Mothers
Abstract Number: SA-16
Abstract Type: Original Research
Introduction: Non-invasive cardiac output (CO) monitoring using bioreactance (NICOM) in pregnant mothers is gaining interest with the potential to predict the evolution of pre-eclampsia and monitor treatment response. However, this method of CO monitoring lacks validation in this population.
Aims: To compare simultaneous CO readings obtained using NICOM and echocardiography (echo) in a group of healthy primagravid pregnant women.
Methods: Simultaneous stroke volume (SV) and CO measurements were obtained using NICOM and echo in a group of healthy primagravid women between 24 and 28 weeks gestation enrolled in a large observational prospective study assessing the ability of NICOM to predict the evolution of pre-eclampsia and intrauterine growth restriction (HANDLE study). Paired SV and CO readings were obtained using NICOM and echo over a 15 minute period in the semi-recumbent position. The echocardiographer was blinded to the NICOM readings during measurement. Agreement between NICOM and echo measurements of SV and CO was assessed using Bland Altman analysis and the intraclass correlation coefficient (ICC). Data were presented as means (SD).
Results: Thirteen mothers with a mean age, weight and gestation of 33 (6) years, 72 (11) Kg and 171 (27) days respectively were enrolled. There was no difference between the mean NICOM and echo SV [74 (12) vs. 80 (21) ml, p=0.2] or the mean NICOM and echo CO [6.4 (1.0) vs. 6.4 (1.0) L, p=0.8] in the cohort. There was good agreement between NICOM and echo measured SV [Mean bias 0 (LOA -1.6 to +1.6 L), ICC 0.8 (95% CI 0.4 – 0.9, p=0.004]. Similarly, there was good agreement between NICOM and echo measured CO [Mean bias 6 (LOA -21 to +33 ml), ICC 0.8 (95% CI 0.4 – 0.9, p=0.004].
Conclusion: SV and NICOM measurements obtained using NICOM are comparable to those obtained using echocardiography. NICOM may be an acceptable method for monitoring the haemodynamic status of pregnant mothers.