Veno-arteriovenous (V-AV) ECMO configuration: A single-center experience.

Background: With increasing extracorporeal membrane oxygenation (ECMO) utilization over the last decade, clinicians have developed "hybrid" configurations to meet complex perfusion requirements. In the setting of differential hypoxemia, a veno-arteriovenous (V-AV) configuration provides oxygenated cardiac preload and hemodynamic support to satisfy physiologic demands. We aim to further characterize the patient population, indications, and outcomes associated with this hybrid configuration.

Methods: We retrospectively reviewed all adult patients placed on V-AV ECMO at our institution from June 2016 to December 2019. Through a review of the electronic medical records, data describing demographic features, comorbidities, and ECMO-specific information were analyzed systematically.

Results: 14 patients were placed on V-AV ECMO during the study period. Our cohort was 79% male with a median age of 54 and BMI of 30.3. These patients had a median SOFA-0 score of 15 and SAVE score of -12. Patients were treated with ECMO support for a median of 144.1 (IQR 98.5 - 183.1) hours, consisting of 0.2 (IQR 0 - 17.7) hours of VA and 92.4 (IQR 53.7 - 115.1) hours of V-AV followed by 67.4 (IQR 20.3 - 96.6) hours of VV support. Of these 14 patients, 11 survived to decannulation (79%) and 9 survived to hospital discharge (64%).

Conclusion: ECMO patients with recovering left ventricular function and persistent gas exchange abnormalities are at risk for developing differential hypoxemia. We describe an approach to utilizing V-AV configuration when the likelihood of differential hypoxemia is extremely high, with a survival rate that compares favorably to Extracorporeal Life Support Organization statistics and published case series.