Proposed Topic (Most preferred): :
Research and Innovations (new projects / technology / innovations / service models)
Authors (including presenting author) :
Cheng YW(1), Ng CH(1), Chan CN(2), Lam HS(2)
Affiliation :
(1) Department of Paediatrics and Adolescent Medicine, Alice Ho Miu Ling Nethersole Hospital (2) Department of Paediatrics, Prince of Wales Hospital
Introduction :
Accurate and continuous measurement of cardiac output (CO) is an important part of evaluating the cardiovascular status in neonates, especially in those with unstable hemodynamics. Invasive methods including pulmonary artery catheter thermodilution and pulse Index continuous cardiac Output (CO) monitor (PiCCO) are too traumatic for neonates. Electrical Velociometry (EV) is a non-invasive method of continuous left cardiac output monitoring based on measurement of thoracic electrical bioimpedance. It has been used in Adult Intensive Care Unit (AICU) for some time already but the usefulness and safety of using such a machine in critically-ill neonates are not well-studied.
Objectives :
The objective was to validate the accuracy of EV by investigating the concordance in cardiac output measurements performed by EV and echocardiography in neonates across different weight ranges and different modalities of respiratory support. We hypothesize that the extremely small size of preterm infants and the different modes of ventilation can interfere with impedance, and therefore affect the accuracy of EV compared with echocardiogram.
Methodology :
This prospective observational study was conducted in the Neonatal unit, department of Paediatrics at Prince of Wales Hospital from 01 January 2022 and 31 March 2022. We used the Electrical Velociometry (EV) machine (ICON®, Osypka Medical, Berlin, Germany) and we obtained 178 simultaneous paired measurements of cardiac output in 49 neonates. We evaluated the concordance of cardiac output measured with Electrical Velocimetry and echocardiogram in neonates with different weight and on different respiratory support modalities. Data were compared by correlation, Bland-Altman analysis and two-way analysis of variance. The study had been approved by the Joint CUHK – NTEC Clinical Research Ethics Committee of the Hospital Authority in Hong Kong.
Result & Outcome :
We studied 178 simultaneous paired measurements of CO in 49 neonates. Their median gestational age (GA) was 32 weeks 5 days (range: 24 weeks 4 day to 40 weeks 6 days, IQR: 30 weeks 6 days to 38 weeks 1 day), weight 1,830 gram (range: 570 to 3620 grams, IQR: 1225 to 2910 grams), postnatal age 2 days (range from 0-7 days, IQR:1-3). 23 (48%) of them were male. There were also no significant effects of mode of ventilatory support on the bias [F (4, 170) = 0.750, P = 0.559] and no interaction effect between PDA and mode of ventilatory support [F (2, 170) = 0.593, P = 0.554]. Cardiac output by EV was 468 +/- 177 ml/min and Echocardiogram was 428 ± 165 ml/min respectively. Pearson coefficient was 0.919 (p < 0.01) and coefficient of determination (R) of 0.845 were seen between 2 measurements.
Conclusion: Our study is likely the largest prospective study using Electrical Velocimetry (EV) to measure the cardiac output in critically ill neonates non-invasively and safely in Hong Kong. It demonstrated a high overall correlation between EC and Echocardiogram in critically ill neonates. In future, studies should aim beyond verification of the accuracy of EC and should focus on its the trending ability to aid physicians in making important clinical decisions and ultimately improving patients’ outcomes. With the important findings of our study, hopefully with wider use of EV in all the neonatal units in Hospital Authority (HA), the survival rate of critically ill neonates in Hong Kong may be further improved.
