Triage of V-V ECMO referrals for COVID-19 respiratory failure

BackgroundAs the pandemic progressed, the use of extracorporeal membrane oxygenation (ECMO) for COVID-19-related acute respiratory distress syndrome increased, and patient triage and transfer to ECMO centers became important to optimize patient outcomes. Our objectives are to identify predictors of patient transfer for veno-venous extracorporeal membrane oxygenation (V-V ECMO) evaluation as well as to describe the outcomes of accepted patients.MethodsThis is a single-center, retrospective analysis of V-V ECMO transfer requests for adult patients with known or suspected COVID-19 and respiratory failure from March 2020 until March 2021. Data were collected prospectively during the triage process for transfer requests as part of clinical patient care at our institution.ResultsOf 341 referred patients, 112 (33%) were accepted for transfer to our facility, whereas 229 (67%) patients were declined for transfer. The Classification and Regression Tree analysis showed that patients' high pressure during airway pressure release ventilation (APRV) and age were the variables most significantly associated with the decision to accept or decline patients for transfer.ConclusionsOur triage process enabled one-third of referred patients to be transferred for evaluation, with nearly 70% of those patients ultimately receiving ECMO support. High ventilator settings on APRV and young age were associated with acceptance for transfer. Accepted patients also had a higher incidence of adjunctive therapies (proning and paralysis) prior to transfer request, less cardiac or renal dysfunction, and a shorter duration of mechanical ventilation. Further research is warranted to investigate the outcomes of nontransferred patients. Factors predicting acceptance for transfer to our extracorporeal membrane oxygenation (ECMO) center for veno-venous ECMO evaluation during the first year of the COVID-19 pandemic were high airway pressure release ventilation settings and young age, and there was a higher percentage of accepted patients who had failed traditional acute respiratory distress syndrome management of paralysis and proning. Several patients accepted for ECMO evaluation were deemed too unstable for transport, highlighting the potential benefit of increasing access with mobile ECMO teams.image