Risk factors for elective and emergency oxygenator exchanges during veno-venous extracorporeal membrane oxygenation

Background Despite systemic anticoagulation and antithrombotic surface coating, oxygenator dysfunction remains one of most common technical complications of Extracorporeal membrane oxygenation (ECMO). Several parameters have been associated with an oxygenator exchange, but no guidelines for when to perform an exchange are published. An exchange, especially an emergency exchange, has a risk of complications. Therefore, a delicate balance between oxygenator dysfunction and the exchange of the oxygenator exists. This study aimed to identify risk factors and predictors for elective and emergency oxygenator exchanges. Methods This observational cohort study included all adult patients supported with veno-venous extracorporeal membrane oxygenation (V-V ECMO). We compared patients' characteristics and laboratory values of patients with and without an oxygenator exchange and between an elective and emergency exchange, defined as an exchange outside office hours. Risk factors for an oxygenator exchange were identified with cox regression analyses, and risk factors for an emergency exchange were identified with logistic regression analyses. Results We included forty-five patients in the analyses. There were twenty-nine oxygenator exchanges in nineteen patients (42%). More than a third of the exchanges were emergency exchanges. Higher partial pressure of carbon dioxide (PaCO2), transmembrane pressure difference (Delta P), and hemoglobin (Hb) were associated with an oxygenator exchange. Lower lactate dehydrogenase (LDH) was the only risk factor for an emergency exchange. Conclusion Oxygenator exchange is frequent during V-V ECMO support. PaCO2, Delta P and Hb were associated with an oxygenator exchange and lower LDH with the risk of an emergency exchange.