The Avalon bicaval catheter has revolutionized venovenous extracorporeal membrane oxygenation (VV-ECMO) by allowing us to place a single catheter that can simultaneously drain venous blood from the central circulation (superior and inferior vena cavas) to deliver oxygenated blood directly into the heart.
How does this work? The catheter has a dual lumen construction (one for venous inflow, one for venous outflow) which requires careful positioning utilizing fluoroscopy or echocardiography. The right internal jugular vein is accessed and a guidewire is threaded past the heart into the inferior vena cava (IVC) with subsequent dilation of the vein using progressively larger dilators. Avalon catheters come in sizes ranging from 13 to 31 French. For comparison, many of the hemodialysis catheters I’ve placed are 13.5 French.
The outflow must be directed towards the tricuspid valve to ensure proper flow during VV-ECMO. By having the catheter in the neck, these patients can ambulate while waiting for a lung transplant, resolution of their pulmonary process, etc. Remember that movement of the catheter can lead to suction events, inadequate flows, or remixing of blood, resulting in hypoxemia.
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