Abstract
Purpose. To examine the effect size of the type of respiratory support and oxygenation indices on the development of different stages of retinopathy of prematurity (RoP).
Material and methods. We retrospectively reviewed the medical records of 290 preterm infants who were under supervision during 2015-2018. The preterm infants were divided into four groups: group 1 of 117 infants without RoP; group 2 of 86 infants with autoregressive RoP; group 3 of 57 infants that required treatment for RoP; and group 4 of 30 infants with aggressive RoP. All these infants underwent ROP screening in accordance with international standards in due time.
Results. There was a significant difference in gestation age (GA) among the four groups (ANOVA: F= 74.13; p < 0.0001), with a significant pairwise difference between most group pairs, but not between groups 3 and 4 (p = 0.9). Additionally, there was a significant difference in birth body weight (BBW) among the four groups (analysis of variance (ANOVA): F= 54.1; p < 0.0001), but the pairwise difference between groups 3 and 4 was not significant (p = 0.9). For FiO2, Welch's ANOVA was applied when the homogeneity of dispersions was violated (Levene’s test p = 0.03): F = 4.6; p = 0.005; the pairwise differences between groups 1 and 3, 2 and 3, and 3 and 4 were significant (p = 0.0006, p = 0.001, and p = 0.048, respectively). The frequency of mechanical ventilation (MV) use increased from group 1 to group 4 (90/117, 71/86, 55/57, and 30/30, respectively), with a significant difference among groups (Kruskal-Wallis test: H = 17.3; p = 0.006). No significant difference among groups was found for the frequency of use of nasal continuous positive airway pressure (NCPAP) (114/117, 85/86, 57/57, and 30/30, respectively; Kruskal-Wallis test: H = 2.4; p = 0.48). Transcutaneously measured oxygen saturation (SpO2) was similar among groups (Welch ANOVA: F = 0.7; p = 0.5). The effect size as measured by partial η² was the largest for GA (0.437) and BBW (0.36) and less for MV (0.05) and FiO2 (0.046).
Conclusion. GA and BBW had the largest effects (with a partial η² of 0.437 and 0.36, respectively) on the development of different stages of RoP. There was a significant difference among groups in FiO2 or the frequency of MV use (indicating their effects on the development of different stages of RoP), but not in SpO2 or the frequency of NCPAP use.