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Does obesity affect the non-invasive measurement of cardiac output performed by electrical cardiometry in children and adolescents?


Electrical cardiometry (EC) is a non-invasive and inexpensive method for hemodynamic assessment and monitoring. However, its feasibility for widespread clinical use, especially for the obese population, has yet to be determined. In this study, we evaluated the agreement and reliability of EC compared to transthoracic Doppler echocardiography (TTE) in normal, overweight, and obese children and adolescents. We measured stroke volume (SV) and cardiac output (CO) of 131 participants using EC and TTE simultaneously. We further divided these participants according to BMI percentiles for subanalyses: <85% normal weight (n = 41), between 85 and 95% overweight (n = 7), and >95% obese (n = 83). Due to small sample size of the overweight group, we combined overweight and obese groups (OW+OB) with no significant change in results (SV and CO) before and after combining groups. There were strong correlations between EC and TTE measurements of SV (r = 0.869 and r = 0.846; p < 0.0001) and CO (r = 0.831 and r = 0.815; p < 0.0001) in normal and OW+OB groups, respectively. Bias and percentage error for CO measurements were 0.240 and 29.7%, and 0.042 and 29.5% in the normal and OW+OB groups, respectively. Indexed values for SV were lower in the OW+OB group than in the normal weight group when measured by EC (p < 0.0001) but no differences were seen when measured by TTE (p = 0.096). In all weight groups, there were strong correlations and good agreement between EC and TTE. However, EC may underestimate hemodynamic measurements in obese participants due to fat tissue.

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We would like to thank Elizabeth Burrill (NP) and Jody Jones (RDMS) for their support recruiting patients and performing echocardiography; and Adam A. Dempsey for his assistance with manuscript revisions.


This study was partially supported by research grants from Western University (ADF-5609-8), Children’s Health Research Institute (LHRF 7712), Innovation Fund of the Alternative Funding Plan of the Academic Health Sciences Centres of Ontario (AMOSO, #INN 12-003) and grant from Children’s Health Foundation, London, Ontario to Dr. K. Norozi.

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Correspondence to Kambiz Norozi.

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Ethical approval

This study was approved by the Western University Health Science Research Ethics Board (REB # 16266E). All children and adolescents gave written consent to participate in this study. For those under 16 years of age, we obtained written consent from caregivers.

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Altamirano-Diaz, L., Welisch, E., Rauch, R. et al. Does obesity affect the non-invasive measurement of cardiac output performed by electrical cardiometry in children and adolescents?. J Clin Monit Comput 32, 45–52 (2018).

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