Radiographic scores as a predictor of oxygenation index in very low-birthweight infants.

Background: Very low birthweight infants (VLBWIs) often undergo chest radiographic examinations without standardization or objectivity. This study aimed to assess the association of two radiographic scores, the Brixia and radiographic assessment of lung edema (RALE), with oxygenation index (OI) in ventilated VLBWIs and to determine the optimal cutoff values to predict hypoxic respiratory severity.

Methods: VLBWIs who received invasive respiratory support with arterial lines between January 2010 and October 2023 were enrolled in this study (n = 144). The correlation between the Brixia or RALE scores and OI was investigated. Receiver operating characteristic curve analysis was performed to determine the optimal cutoff points of the two radiographic scores for predicting OI values (OI ≥5, ≥10, and ≥15).

Results: The enrolled infants had a median gestational age of 27 weeks (interquartile range [IQR], 25-28 weeks) and a median birthweight of 855 g (IQR, 684-1003 g). Radiographic scoring methods correlated with the OI (Brixia score: r = 0.79, p < 0.001; RALE score: r = 0.72, p < 0.001). The optimal cutoff points for predicting OI values were as follows: Brixia score: OI ≥5, 10; OI ≥10, 13; OI ≥15, 15; RALE score: OI ≥5, 22; OI ≥10, 31; and OI ≥15, 40.

Conclusions: Brixia and RALE scores are useful predictive markers of the oxygenation status in intubated VLBWIs with stable hemodynamics. These scores are easy to use and promising tools for clinicians to identify patients with a higher risk of hypoxic respiratory failure.