High initial dose of fractional inspired oxygen could reduce mortality in premature infants, study finds

Researchers have found that resuscitation with higher levels of fractional inspired oxygen (FiO2) significantly reduces mortality in preterm infants born at less than 32 weeks’ gestation. This finding is based on a comprehensive network meta-analysis (NMA) of individual participant data (IPD) from multiple randomized clinical trials. The study was recently published in JAMA Pediatrics by James X. and his colleagues.

Although the benefits of lowering FiO2 in term and near-term infants are well documented, their impact on very preterm infants is unclear. This study aims to evaluate the relative effectiveness of different initial FiO2 levels in reducing mortality, severe morbidities, and achieving optimal oxygen saturations (SpO2) in infants born before 32 weeks’ gestation.

The analysis included data from MEDLINE, Embase, CENTRAL, CINAHL, ClinicalTrials.gov and WHO ICTRP, covering the period 1980 to October 10, 2023. Eligible studies were randomized clinical trials involving infants born less than 32 weeks gestation. These trials compared at least two different initial oxygen concentrations for delivery room resuscitation, classified as low (≤ 0.3), intermediate (0.5-0.65), or high (≥ 0.90) FiO2 . Researchers from eligible studies were invited to contribute to their IPD. The data has been meticulously processed and checked for quality and integrity. A one-step Bayesian contrast-based IPD-NMA was performed using uninformative priors and random effects, adjusted for key covariates.

The primary outcome measure was all-cause mortality at hospital discharge. Secondary outcomes included morbidities associated with prematurity and SpO2 levels 5 minutes after resuscitation.

Data were obtained for 1,055 infants from 12 of 13 eligible studies conducted between 2005 and 2019.
French Results revealed that resuscitation with high initial FiO2 (≥0.90) was associated with significantly reduced mortality compared with low FiO2 (≤0.3) (odds ratio (OR), 0.45; credible interval (CrI), 0.23-0.86; low certainty) and intermediate (0.5-0.65) (OR, 0.34; 95% CRI, 0.11-0, 99; very low certainty).
High initial FiO2 had a 97% probability of being the first to reduce mortality. However, the effects on other morbidities were inconclusive.

These results suggest that a high initial FiO2 (≥0.90) may be more effective in reducing mortality in preterm infants born at less than 32 weeks’ gestation compared with lower FiO2 levels. Although the certainty of these findings varies, the data support consideration of higher FiO2 levels during resuscitation in this vulnerable population.

High initial FiO2 (≥0.90) may significantly reduce mortality in premature infants born before 32 weeks of gestation compared to low initial FiO2, but with low certainty. The potential advantage of high FiO2 over intermediate FiO2 is suggested but requires further evidence. These findings could influence resuscitation protocols to improve outcomes for premature infants.

Reference:

Sotiropoulos, JX, Oei, JL, Schmölzer, GM, Libesman, S., Hunter, KE, Williams, JG, Webster, AC, Vento, M., Kapadia, V., Rabi, Y., Dekker, J., Vermeulen , MJ, Sundaram, V., Kumar, P., Kaban, RK, Rohsiswatmo, R., Saugstad, OD and Seidler, AL (2024). Initial oxygen concentration for resuscitation of infants born less than 32 weeks gestation: a systematic review and network meta-analysis of individual participant data. JAMA Pediatrics. https://doi.org/10.1001/jamapediatrics.2024.1848