346 - A Study on Clinical Impact of Repeated Surfactant Dosing in Extremely Preterm Infants (< 28 Weeks Gestation) with Respiratory Distress Syndrome

Publication Number: 2335.346

Jay Pandya, University of Florida College of Medicine Jacksonville, Jacksonville, FL, United States; Vasantha HS. Kumar, University of Florida College of Medicine, Jacksonville, FL, United States; Padma Nandula, Unive, Jacksonville, FL, United States; Sanket Shah, University of Florida College of Medicine, Jacksonville, FL, United States

Background: Respiratory distress syndrome (RDS) is a common complication of prematurity resulting from surfactant deficiency. Early surfactant therapy has been shown to improve respiratory outcomes in preterm infants. However, some infants with severe RDS require repeated surfactant doses, which may be associated with altered lung physiology and potentially adverse outcomes. The long-term benefits or risks of multiple surfactant administration remain unclear.

Objective: To compare composite clinical outcomes in extremely preterm infants (EPI, < 28 weeks gestation) who received single dose (SD) versus multiple doses (MD) of surfactant.

Design/Methods: We conducted a retrospective cohort study of EPI patients admitted to the level III NICU at the University of Florida Health between January 1, 2017, and October 31, 2025. Infants with chromosomal or major congenital anomalies, those who died < 24 hours of age, or who did not receive surfactant were excluded. All infants received surfactant via endotracheal tube. Comparisons between groups were performed using Wilcoxon rank-sum and Chi-square tests, as appropriate.

Results: Of the 404 eligible infants, 279 infants received SD while 125 infants received MD of surfactant. Baseline characteristics were similar between groups, except for a higher rate of preeclampsia in the MD group (36% vs. 17.2%, p = 0.001; Table 1). Infants in the MD group had higher rates of pneumothorax (16.8% vs. 5%, p < 0.001) and higher respiratory severity scores at 7 and 28 days of life (p < 0.001 and p = 0.046, respectively). They also experienced longer invasive ventilation (26 vs. 17 d, p = 0.03) and delayed extubation (18 vs. 7 d, p = 0.003). Severe bronchopulmonary dysplasia (BPD; 33% vs. 20.1%, p = 0.01) and retinopathy of prematurity requiring treatment (ROP; 25% vs. 12.1%, p = 0.003) were more common in the MD group, while length of stay, weight velocity, and the need for tracheostomy were similar in both groups.

Conclusion(s): EPI requiring multiple doses of surfactant had greater short-term respiratory morbidity and a higher incidence of severe BPD and ROP compared to those receiving a single dose. These findings likely reflect a lack of lung development, presenting as an increased illness severity in these infants. A clinically significant difference in GA supports the association of lung immaturity with multiple surfactant doses and adverse outcomes. Infants who require multiple surfactant doses should be recognized as a high-risk group warranting close respiratory follow-up and early interventions aimed at mitigating chronic lung disease.

Table 1: Baseline Characteristics
^ counts (percentage); * median (IQR)
pCO2: partial pressure of carbon dioxide

Table 2: Neonatal Outcomes
^ counts (percentage); * median (IQR)
RSS: respiratory severity score; IVH: Intraventricular hemoorhage; DOL: Days of life; PMA: postmenstrual age; NEC: Necrotizing enterocolitis; BPD: Bronchopulmonary dysplasia; PDA: patent ductus arteriosus
Severe BPD defined as grade 2 and grade 3 BPD per Jensen Criteria