Non-Invasive Cardiac Output Monitoring in Preterm Infants Undergoing Patent Ductus Arteriosus Ligation: A Comparison with Echocardiography

Abstract

Background: Non-invasive cardiac output monitoring (NICOM; NICOM™) may be useful in the management of extremely premature preterm infants. Objectives: To evaluate a new bioreactance-based method of continuous NICOM in preterm infants following patent ductus arteriosus (PDA) ligation. Methods: Infants underwent three paired NICOM and echocardiography assessments of stroke volume (SV) and left ventricular output (LVO) in the postoperative period: at 1, 6-8, and 16-18 h postoperatively. NICOM- and echocardiography-measured SV and LVO during those periods were compared using Bland-Altman analysis and the intraclass correlation coefficient (ICC). Results: Twenty-five infants with a median (interquartile range) gestational age and birth weight of 25.0 weeks (24.5-25.9) and 700 g (615-775), respectively, were included. The overall systematic bias (limits of agreement) across all time points between the NICOM and echocardiography SV readings was 39% (8-69) with NICOM consistently underestimating echocardiography values. There was moderate consistency between NICOM and echocardiography SV values (ICC 0.78, p < 0.001). Compared with the 1-hour scans, the 6- to 8- and 16- to 18-hour scans had increased biases of 7.9% (95% CI 2.5-13.2) and 9.7% (95% CI 3.6-15.8), respectively. Conclusion: Continuous LVO measurement using NICOM was feasible and demonstrated a consistent systematic bias compared with echocardiography in unstable extremely preterm infants without a PDA ligation. NICOM may be used as a trending tool for continuous monitoring in this population, but wide limits of agreement and increasing bias over time suggest it is not interchangeable with echocardiography.

Hemodynamic monitoring of the critically ill neonate: An eye on the future

“…Whereas CO gradually improved by 24 h post ligation, the postoperative increase in SVR was sustained throughout the study period. Although this study performed intermittent rather than continuous hemodynamic assessments due to the use of oscillometric blood pressure measurements, their observations are consistent with the findings reported by Weisz et al [64]. Both of these studies also highlight the importance of further efforts to validate non-invasive CO monitoring systems in neonates and that caution should be used when interpreting the measurements obtained by the use of the novel technologies alone.…”

“…Weisz et al [64] studied postoperative CO changes in extremely premature infants after PDA ligation using echocardiography and a non-invasive CO-monitoring system based on thoracic bioreactance (NICOM) [27]. Based on high versus low LVO at 1 h after ligation, the authors identified two groups of patients.…”

Diagnosis and Management of Patent Ductus Arteriosus

“…Various approaches include interpretation of pulse oximetry information (perfusion index, plethysmography), (19)(20)(21) interpretation of transthoracic electrical signals (impedance, cardiometry, velocimetry, bioreactance), (22)(23)(24)(25) regional oxygenation (near-infrared spectroscopy), (26) alterations in skin microcirculation (side stream dark-field imaging, reflectance spectrophotometry), (27)(28) resonance Raman spectroscopy (Lauren J. Ruoss, personal communication, May 2018), and others.…”

Anticipatory perioperative management for patent ductus arteriosus surgery: Understanding postligation cardiac syndrome

“…32 Using bioreactance to continuously monitor cardiac output postligation, milrinone monotherapy for postoperative LVO less than 200 ml/min/kg has been shown to be associated with recovery of LVO. 34 In a retrospective cohort of neonates with low LVO 1-hour postligation, treatment with prophylactic milrinone was associated with improved LVO and tissue Doppler systolic velocities in the lateral and septal wall, with no significant effects on diastolic markers. 31 This suggests that the primary mechanism of action is related to improved systolic function with afterload reduction rather than lusitropy.…”