learnECMO 5: ECMO Haemodynamics

by Steve Morgan & Sophie Connolly Today we are going to cover the essentials of ECMO haemodynamics. Haemodynamics literally means blood movement and thus is the physical study of flowing blood and the structures through which it flows. In bedside vernacular we tend to use haemodynamics to refer to accessible surrogate measurements of cardiovascular performance, such as vascular and chamber pressures or quantifications of macrocirculatory blood flow. To understand the haemodynamic effects of ECMO we will consider the effects of the in-parallel VA circuit and the in-series VV circuit separately. The effect on cardiac performance can be best approached and compartmentalised by examining the impact of ECMO on each of the determinants of stroke volume: preload, afterload and contractility. This podcast covers: How can we best describe ventricular function and the effect of ECMO? What factors influence the net effect of VA ECMO on patient haemodynamics? What are the general primary haemodynamic effects of VA ECMO? How does cannulation site influence the haemodynamics of VA ECMO? What do you do about a non-ejecting heart on VA ECMO? What about the RV? How does the unique functional anatomy and physiology contribute to RV failure? What are the haemodynamic effects of VA ECMO on the RV? What are the haemodynamic effects of VV ECMO?