Background: Extracorporeal membrane oxygenation (ECMO) has emerged as a life-sustaining measure for individuals with end-stage cardiopulmonary derangements. An estimated one-third of patients must be transferred to a specialized center to receive this intervention. Therefore, the present study sought to characterize the impact of interhospital transfer (IHT) status on outcomes following ECMO.
Methods: The 2016-2020 National Inpatient Sample was queried to identify all adult (≥18 years) hospitalizations for ECMO. Patients were stratified based on transfer status from another acute care hospital. Multivariable regression models were developed to assess the association between transfer status and outcomes of interest. Patient and operative factors associated with IHT were identified using regression.
Results: Of an estimated 61,180 hospitalizations entailing ECMO, 21,410 (35.0%) were transfers. Annual transfer volume doubled over the study period, from 2915 to 5945 (nptrend < .001). The predicted morality risk of non-transfers decreased between 2016 and 2020 but remained similar in transferred patients. Following adjustment, transfer was associated with increased odds of in-hospital mortality, complications, duration of stay, and hospitalization costs. Patients experiencing transfer were less likely to be of black race and private insurance status.
Conclusion: Despite increasing transfer volume and utilization of ECMO, IHT was associated with significant mortality and hospital complication risks. Further work to reduce adverse outcomes, resource burden, and socioeconomic differences within IHT may improve accessibility to this life-saving modality.
Keywords: HCUP; National Inpatient Sample; extracorporeal membrane; interhospital transfer; oxygenation.