Fluid dynamic model for extracorporeal membrane oxygenation support and perfusion in cardiogenic shock

Abstract

The venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a widely adopted procedure to provide oxygenated blood support in patients who underwent cardiac shock. The current work presents a study to define a correlation between VA-ECMO support level and both systemic pressure and arterial perfusion. In this work, a numerical approach is defined on a patient-specific aortic geometry to validate this trend on a more complete case and also to investigate the behavior of the mixing zone. In particular, morphological data from computed tomography imaging of a patient-specific whole aorta, including supra aortic vessels, coronaries, and renal arteries, were adopted for the study. A computational fluid dynamic approach was set for the analysis. A total of three cardiogenic shock cases (mild, medium, and severe) were simulated. For each shock configuration, different levels of ECMO support were simulated (0–6 l/min flow range). The aortic fluid dynamics were evaluated in terms of systemic afterload, watershed zone position, and perfusion of arteries. A linear trend of the perfusion as a function of ECMO level support was investigated and successfully validated. The minimum level of ECMO support to grant the perfusion of all arteries, causing the minimum possible afterload increase, was individuated and fitted with a linear model against different levels of cardiogenic shock. The results presented demonstrated to be a first step to have a preliminary tool to establish the minimum level of ECMO support for overall perfusion as a function of cardiogenic shock percentage.