To systematically review and meta-analyze the validity of electrical bioimpedance-based noninvasive cardiac output monitoring in pediatrics compared with standard methods such as thermodilution and echocardiography.DATA SOURCES: Systematic searches were conducted in MEDLINE and EMBASE (2000-2019). STUDY SELECTION:Method-comparison studies of transthoracic electrical velocimetry or whole body electrical bioimpedance versus standard cardiac output monitoring methods in children (0-18 yr old) were included. DATA EXTRACTION:Two reviewers independently performed study selection, data extraction, and risk of bias assessment. Mean differences of cardiac output, stroke volume, or cardiac index measurements were pooled using a randomeffects model (R Core Team, R Foundation for Statistical Computing, Vienna, Austria, 2019). Bland-Altman statistics assessing agreement between devices and author conclusions about inferiority/noninferiority were extracted.DATA SYNTHESIS: Twenty-nine of 649 identified studies were included in the qualitative analysis, and 25 studies in the meta-analyses. No significant difference was found between means of cardiac output, stroke volume, and cardiac index measurements, except in exclusively neonatal/infant studies reporting stroke volume (mean difference, 1.00 mL; 95% CI, 0.23-1.77). Median percentage error in child/adolescent studies approached acceptability (percentage error less than or equal to 30%) for cardiac output in L/min (31%; range, 13-158%) and stroke volume in mL (26%; range, 14-27%), but not in neonatal/infant studies (45%; range, 29-53% and 45%; range, 28-70%, respectively). Twenty of 29 studies concluded that transthoracic electrical velocimetry/whole body electrical bioimpedance was noninferior. Transthoracic electrical velocimetry was considered inferior in six of nine studies with heterogeneous congenital heart disease populations. CONCLUSIONS:The meta-analyses demonstrated no significant difference between means of compared devices (except in neonatal stroke volume studies). The wide range of percentage error reported may be due to heterogeneity of study designs, devices, and populations included. Transthoracic electrical velocimetry/ whole body electrical bioimpedance may be acceptable for use in child/adolescent populations, but validity in neonates and congenital heart disease patients remains uncertain. Larger studies in specific clinical contexts with standardized methodologies are required.

Background:This review aims to summarize associations of the perinatal environment with arterial biophysical properties in childhood, to elucidate possible perinatal origins of adult cardiovascular disease (CVD).Methods:A systematic search of PubMed database was performed (December 2020). Studies exploring associations of perinatal factors with arterial biophysical properties in children 12 years old or less were included. Properties studied included: pulse wave velocity; arterial stiffness or distensibility; augmentation index; intima–media thickness of aorta (aIMT) or carotids; endothelial function (laser flow Doppler, flow-mediated dilatation). Two reviewers independently performed study selection and data extraction.Results:Fifty-two of 1084 identified records were included. Eleven studies explored associations with prematurity, 14 explored maternal factors during pregnancy, and 27 explored effects of low birth weight, small-for-gestational age and foetal growth restriction (LBW/SGA/FGR). aIMT was consistently higher in offspring affected by LBW/SGA/FGR in all six studies examining this variable. The cause of inconclusive or conflicting associations found with other arterial biophysical properties and perinatal factors may be multifactorial: in particular, measurements and analyses of related properties differed in technique, equipment, anatomical location, and covariates used.Conclusion:aIMT was consistently higher in LBW/SGA/FGR offspring, which may relate to increased long-term CVD risk. Larger and longer term cohort studies may help to elucidate clinical significance, particularly in relation to established CVD risk factors. Experimental studies may help to understand whether lifestyle or medical interventions can reverse perinatal changes aIMT. The field could be advanced by validation and standardization of techniques assessing arterial structure and function in children.