Association of prehospital post-resuscitation peripheral oxygen saturation with survival following out-of-hospital cardiac arrest.

Background: Hypoxia and hyperoxia following resuscitation from out-of-hospital cardiac arrest (OHCA)may cause harm by exacerbating secondary brain injury. Our objective was to retrospectively examine theassociationof prehospital post-ROSC hypoxia and hyperoxia with the primary outcome of survival to discharge home.

Methods: We utilized the 2019-2021 ESO Data Collaborative public use research datasets for this study (ESO, Austin, TX). Average prehospital SpO, lowest recorded prehospital SpO, and hypoxia dose were calculated for each patient. Theassociationof these measures with survival was explored using multivariable logistic regression. We also evaluated theassociationof American Heart Association (AHA) and European Resuscitation Council (ERC) recommended post-ROSC SpO target ranges with outcome.

Results: After application of exclusion criteria, 19,023 patients were included in this study. Of these, 52.3% experienced at least one episode of post-ROSC hypoxia (lowest SpO < 90%) and 19.6% experienced hyperoxia (average SpO > 98%). In comparison to normoxic patients, patients who were hypoxic on average (AHA aOR: 0.31 [0.25, 0.38]; ERC aOR: 0.34 [0.28, 0.42]) and patients who had a hypoxic lowest recorded SpO (AHA aOR: 0.48 [0.39, 0.59]; ERC aOR: 0.52 [0.42, 0.64]) had lower adjusted odds of survival. Patients who had a hyperoxic average SpO (AHA aOR: 0.75 [0.59, 0.96]; ERC aOR: 0.68 [0.53, 0.88]) and patients who had a hyperoxic lowest recorded SpO (AHA aOR: 0.66 [0.48, 0.92]; ERC aOR: 0.65 [0.46, 0.92]) also had lower adjusted odds of survival.

Conclusion: Prehospital post-ROSC hypoxia and hyperoxia were associated with worse outcomes in this dataset.