(1510) Dual Oxygenators for Refractory Hypercapnia and Hypoxia on ECMO: An Underutilized Therapy?

Introduction: Refractory hypercapnia or hypoxia in patients supported with extracorporeal membrane oxygenation (ECMO) is a rare but morbid phenomenon. Treatment often involves progressively higher amounts of inspired oxygen or ventilator pressures, increasing the likelihood of ventilator-induced lung injury. Greater amounts of PEEP, plateau pressure, or driving pressure have all been previously correlated with increased odds of mortality and prolonged pulmonary recovery. Providing lung-protective ventilation in this cohort would increase cardiac return and improve short and long-term pulmonary outcomes. We hypothesized that the addition of a second oxygenator to the ECMO circuit would allow better control of gas exchange in these critically ill patients.

Methods: All adult patients who required an additional oxygenator between November 2021 and July 2023 at our institution were included. The two oxygenators were configured in parallel with a centrifugal ECMO circuit.

Results: Nineteen patients met criteria with a mean ± SD BMI of 36.5 ± 7.8 and age of 43 ± 13 years (84% male). Indications included COVID-19 in 63%, ARDS in 26%, pneumonia in 5%, and cardiogenic shock in 5%. VV ECMO was utilized in 58% and VPa ECMO in 42%. There was a 53% increase in post-oxygenator pO2 (151 mmHg), 45% increase in systemic pO2 (110 mmHg), 13% decrease in systemic pCO2 (6.1 mmHg), 10% decrease in sweep (1.0 L/min), and 16% decrease in FiO2 (14.5%).

Conclusions: The addition of a second oxygenator in patients with refractory hypercapnia or hypoxia is associated with improved blood gas metrics and a reduced fraction of inspired oxygen. It may be that certain patient-specific factors including habitus, comorbidities, or indication for ECMO support increase the likelihood of requiring an additional oxygenator. Further research should focus on earlier identification of patients would benefit from this modification in their ECMO support.