Modelling and numerical simulation of Veno-Venous Extra-Corporeal Membrane Oxygenation (VV-ECMO)
Date: Tuesday, May 23, 2023
Time: 1:45 pm, S2 416-1
Abstract:
Extra-Corporeal Membrane Oxygenation (ECMO) is a well-established procedure used in Intensive-
Care Units (ICU) to treat patients with either pulmonary or heart failure. The blood of the patient
is drawn via a cannula, oxygenated and injected via another cannula. The extraction cannula is normally
located in the inferior vena cava. In the case of lung failure, but with a heart in good conditions,
the injection cannula is placed in the superior vena cava (veno-venous, VV-ECMO). In the case of
heart failure, the injection cannula is placed in the aorta (veno-arterial, VA-ECMO) to ensure that
the blood is actually pumped across the arterial system. VV-ECMO is the standard procedure in the
case of Severe Acute Respiratory Syndrome and is currently used for Covid-19 patients in ICU. A
known clinical problem for VV-ECMO is recirculation, where a significant portion of the fully oxygenated
blood appears to be recaptured by the extraction cannula in the inferior vena cava, instead of
joining the normal circulation pathway [1]. This results in a limited efficacy of the procedure: blood
is inserted fully oxygenated but distal measurements show values as low as 80%.
In this talk we will present our work on patient-specific modelling and simulation of VV-ECMO,
a surprisingly uncharted territory in the current scientific literature. We will describe the major modelling
challenges that ECMO poses, with a particular focus on the proper description of the blood
flow. The patient geometry is reconstructed from a CT scan, while blood flow and oxygen diffusion
are approximated by the Finite Element Method. We will present numerical results showing
how poorly the standard VV-ECMO actually performs and we will discuss possible optimisation
procedures or best practices to improve its effectiveness.