Novel Method for Percutaneous ECMO Cannula Exchange

ABSTRACT

Purpose: Percutaneous cannulation for Veno-Venous (V-V) and Veno-Pulmonary Arterial (V-PA) ECMO has transformed our approach to extracorporeal support, particularly in the Covid-19 era. Along with the increase in percutaneous cannulation comes an increase in complications, some necessitating replacement of the cannula. We present a novel technique to exchange cannulas using the same site with minimal blood loss and time off support. Method: All procedures were performed in the hybrid OR with fluoroscopy and transesophageal echocardiography (TEE). A 4 Fr. dilator was placed posteromedial to the existing cannula with pressure directed toward the cannula to enter the vein. A wire was placed through the dilator to facilitate directing the wire into the PA or IVC, ultimately advancing the wire into the RPA (V-PA) or IVC (V-V). The ECMO circuit was clamped and both limbs transected. The existing cannula was removed simultaneously with the new cannula being placed over the wire into either PA or IVC (V-PA or V-V respectively). The cannula was deaired, reconnected to the ECMO circuit, and flow reestablished. Results: 8.1% (19/234) of our V-V or V-PA patients required replacement of the percutaneous cannula. 63% were due to RV failure diagnosed by echocardiography and 32% were for cannula migration below the pulmonary valve into the RV. Our technique was universally successful with a mean blood loss of 20cc, <1.5 minutes off ECMO, and no complications. Summary: The described technique is effective in replacing percutaneous V-V and V-PA ECMO cannulas using the original site with minimal time off support and blood loss. (Figure Presented).