64 A. G. Beshish et al.: J Extra Corpor Technol 2025, 57, 59 – 65
Table 3. New morbidity and unfavorable functional outcome for overall survivors who required VV-ECLS stratified by PaO 2 levels into hyperoxia and non-hyperoxia groups based on functional status scale change from admission to discharge.
ECLS group
Overall cohort of survivors( n = 81)
Non-hyperoxia group PaO 2 122( n = 70)
Hyperoxia group PaO 2 > 122 mmHg( n = 11)
New morbidity( change in FSS 3 points) |
22( 27.2 %) |
20( 28.6 %) |
2( 18.2 %) |
0.471 |
Unfavorable outcome( change in FSS 5 points) |
6( 7.4 %) |
5( 7.1 %) |
1( 9.1 %) |
0.819 |
p-value
FSS Subscale scores range from 1 to 5. Total scores are the sum of subscale scores ranging from 6 to 30. FSS: Functional Status Scale; ECLS: Extracorporeal Life Support. patients in hopes of improving overall outcomes, including morbidity and mortality.
Limitations
Our findings are subject to all limitations inherent to singlecenter retrospective cohort studies. Although samples to measure PaO 2 were obtained at dedicated time intervals, it is not possible to discern the effect of time spent in a hyperoxia state as opposed to the effects of acutely high PaO 2 levels. Additionally, there may be some bias as to which patients are exposed to hyperoxia. For example, we show that patients in the hyperoxia group are older and have a smaller number of neonates. This could be related to the oxygen management strategies in the neonatal population. Despite that, when controlling for age group in the multivariable analysis the association between hyperoxia and mortality persisted. The majority of our cohort had a PaO 2 level near or above the cut-off of 122 mmHg while on VV-ECLS limiting our ability to study the relationship between lower oxygen tension levels and outcomes. Although we identified a cut point for PaO 2 of 122 mmHg using an AUC, the sensitivity was 41 %. The sensitivity is low, and this is clearly a limitation of our study that we think can be overcome with a larger patient population that is more homogenous. Importantly, many of these limitations can be addressed in a multicenter validation study, which our group is currently pursuing.
Conclusions
Of the 110 VV-ECLS runs in 107 patients, using an ROC curve the optima paO 2 associated with mortality was 122 mmHg( sensitivity 41 %, specificity 86 %). Patients in the hyperoxia group were older, had higher weight and BSA, and had higher mortality rates. Children exposed to hyperoxia during the first 48 hours of VV-ECLS were 8 times more likely to die than those who were not exposed to hyperoxia. Multicenter and prospective evaluation of this modifiable risk factor is imperative to improve the care of this high-risk cohort.
Funding This research did not receive any specific funding.
Conflicts of interest The authors declared no conflict of interest.
Data availability statement All available data are incorporated into the article.
Author contribution statement
ABandHVdesignedthestudy. PR-M, RS, JQ, K. K-L, TZ, and AB, performed the research and analyzed the data. A. B. wrote the manuscript, and all authors contributed to the final version.
Ethics approval
Data collection was conducted as a retrospective cohort study to determine the ranges of PaO 2 exposure and the potential association between exposure to hyperoxia and poor outcomes. Our primary aim was to determine if hyperoxia while on VV-ECLS was associated with increased mortality using a derived cut-point within our cohort. Our secondary aim was to determine if hyperoxia during VV-ECLS is associated with greater odds of morbidity using the Functional Status Scale( FSS), and the development of complications while on ECLS, including acute kidney injury( AKI). The study protocol conformed to the Declaration of Helsinki and was approved Children’ s Healthcare of Atlanta Institutional Review Board: Study ID No.( IRB # 00001239), approved on 10 / 11 / 2022 in Children’ s Healthcare of Atlanta, Atlanta, Georgia, USA. Medical research is subject to ethical standards that promote and ensure respect for all human subjects and protect their health and rights.
Supplementary material
Supplementary material is available at https:// www. ject. edpsciences. org / 10.1051 / ject / 2024013 / olm. Supplemental Table 1. PaO 2 by primary outcome. Supplemental Table 2. Univariable logistic regression.
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