Clinical Interventions and Hemodynamic Monitoring in the Setting of Left Ventricular Systolic Heart Failure in Children: Insights From a Physiologic Simulator

Abstract

Background: In pediatric critical care, vasoactive/inotropic support is widely used in patients with heart failure, but it remains controversial because the influence of multiple medications and the interplay between their inotropic and vasoactive effects on a given patient are hard to predict. Robust evidence supporting their use and quantifying their effects in this group of patients is scarce. Study Question: The aim of this study was to characterize the effect of vasoactive medications on various cardiovascular parameters in pediatric patient with decreased ejection fraction. Study Design: Clinical-data based physiologic simulator study. Measure and Outcomes: We used a physics-based computer simulator for quantifying the response of cardiovascular parameters to the administration of various types of vasoactive/inotropic medications in pediatric patients with decreased ejection fraction. The simulator allowed us to study the impact of increasing medication dosage and the simultaneous administration of some vasoactive agents. Correlation and linear regression analyses yielded the quantified effects on the vasoactive/inotropic support. Results: Cardiac output and systemic venous saturation significantly increased with the administration of dobutamine and milrinone in isolation, and combination of milrinone with dobutamine, dopamine, or epinephrine. Both parameters decreased with the administration of epinephrine and norepinephrine in isolation. No significant change in these hemodynamic parameters was observed with the administration of dopamine in isolation. Conclusions: Milrinone and dobutamine were the only vasoactive medications that, when used in isolation, improved systemic oxygen delivery. Milrinone in combination with dobutamine, dopamine, or epinephrine also increased systemic oxygen delivery. The induced increment on afterload can negatively affect systemic oxygen delivery.