Is hyperoxia during veno-arterial extracorporeal life support due to cardiopulmonary failure associated with mortality in pediatric patients?

Background: Data is limited regarding the effects of supraphysiologic blood oxygen tension in patients requiring extracorporeal life support (ECLS). We sought to evaluate the association between hyperoxia and outcomes in pediatric patients requiring veno-arterial (VA) ECLS. Methods: Retrospective single-center study at an academic children’s hospital that included all patients 0–18 years who required VA-ECLS between 01/2014 and 12/2019. Results: During the study period, 229 VA-ECLS runs occurred in 229 patients. The majority of patients were neonates (73.4%), with cardiac being the most common indication (48.9%). The median time from admission to cannulation was 78.5 h (IQR 14, 356) with a median ECLS duration of 111.5 h (IQR 65.5, 184.5). The overall mortality rate was 44.5%. Using a receiver operating curve, a mean PaO2 of 233 mmHg in the first 48 h of ECLS was determined to have the optimal discriminatory ability for mortality (sensitivity 36% and specificity 76%). Of the VA-ECLS cohort, 68 (29.7%) had a mean PaO2 > 233 mmHg (hyperoxia group). The hyperoxia group tended to be older (median age 4.6 vs 1.5 months, p = 0.019), had a primary cardiac indication for VA-ECLS (60% vs 44%, p = 0.0004), and had a higher mortality rate (54% vs 40%, p = 0.050). In the multivariable analysis, after adjusting for covariables, the data demonstrated increased odds of mortality (aOR 2.02, 95% CI [1.03, 3.97], p = 0.03). The odds of development of stage II or III acute kidney injury (AKI) (aOR 2.04, 95% CI [0.82, 5.50]), but that did not reach statistical significance (p = 0.120). Conclusion: There is evidence that hyperoxia during the first 48 h of VA-ECLS may be associated with mortality and development of acute kidney injury, although this did not reach statistical significance. Multicenter and prospective evaluation of this modifiable risk factor is imperative to improve the care of this high-risk cohort.