Right ventricular rupture and tamponade caused by malposition of the Avalon cannula for venovenous extracorporeal membrane oxygenation

The Avalon Elite bicaval dual lumen cannula (Avalon Laboratories, Rancho Dominguez, CA) has been used for venovenous extracorporeal oxygenation (VV-ECMO) [1,2]. The cannula consisted of 2 lumens: one lumen allows the deoxygenated blood to drain from the distal and proximal ports, from the inferior vena cava (IVC) and the superior vena cava (SVC), respectively; and a second lumen allows the oxygenated blood to return from the external pump to the right atrium directed toward the tricuspid valve (Figure 1). We have used the Avalon cannula for adult VV-ECMO in salvageable patients with severe refractory adult respiratory distress syndrome (ARDS) since 2009. We have performed VV-ECMO in 4 patients specifically using the Avalon cannula system since then, with successful weaning in all 4 patients. We describe one patient who developed right ventricular rupture and acute cardiac tamponade at the time of cannula insertion.A 53 year old female without significant past medical history developed severe viral pneumonia, with rapid, progressive deterioration in her respiratory status. She developed ARDS and mechanical ventilatory management using ARDS protocol were unable to maintain adequate oxygenation. As a result, bedside VV-ECMO was planned. Transesophageal echocardiography (TEE) was performed to visualize proper positioning of the guidewire and cannula. Using the Seldinger technique, the right internal jugular vein was accessed and a guide wire was placed. Placement of the guidewire into the IVC proved difficult due to repeated migration of the guidewire into the right ventricle. After multiple attempts, the guidewire was visualized to course properly from the SVC to the IVC. After a bolus dose of 5000 units of intravenous heparin was given, the right internal jugular venous access site was dilated. Just as the final dilatation was completed and upon dilator exchange with simultaneous advancement of the 23 French Avalon cannula, TEE lost visualization of the guidewire. Mul