Abstract 12990: The Association of Modifiable Mechanical Ventilation Settings, Blood Gas Changes and Survival After Extracorporeal Cardiopulmonary Resuscitation

Abstract

Introduction: Gas exchange during ECMO can occur independent of the lungs through ECMO, enabling a wider range of ventilator settings and blood gas values. Yet it is not known if potentially modifiable mechanical ventilation parameters or blood gas values are associated with survival for patients who receive ECPR. Hypothesis: To determine associations between ventilation parameters, blood gas values, and survival. Methods: Cohort analysis among 7,488 ECPR patients ≥18yrs of age from the Extracorporeal Life Support Organization (ELSO) Registry from 2008 - 2019. We examined the association between mechanical ventilation parameters on-ECMO with case-mix adjusted hospital survival. We used generalized estimating equation logistic regression, accounting for center level variation. Results: Case-mix adjusted patient-level mechanical ventilation parameters and blood gas values on-ECMO varied across individual hospitals, including arterial pressure of oxygen (PaO2) and carbon dioxide (PaCO2), and changes in these values from pre-ECMO to on-ECMO. Increasing absolute on-ECMO PaO2 (OR 0.88 [95% CI 0.86, 0.9]; p<0.001), and relative increases in PaO2 from pre- to on-ECMO (OR 0.91 [0.89,0.93]; p<0.001) were both associated with decreased survival. Relative increases in pre- to on-ECMO PaCO2 (OR 1.31 [1.14, 1.1.54]; p<0.001) were associated with improved survival. Decreasing peak inspiratory pressure (OR 0.77, per 5 centimeters of water (cmH2O) [0.72, 0.81]; p<0.001) and fraction of inspired oxygen (OR 0.94, per 5% [0.92, 0.96]; p<0.001) were both associated with improved survival. Conclusions: Mechanical ventilation parameters of ECPR patients varies across hospitals. Potentially modifiable parameters and blood gas values are associated with survival and should be the focus of future research.