Objective: To identify prenatal and postnatal risk factors associated with surfactant redosing. Study design: Retrospective, single-regional center study including all infants born from 24 + 0 to 31 + 6 weeks of gestation in the Marche Region, Italy, and admitted to a single level III regional NICU from January 1, 2004, to February 28, 2021. Clinical factors associated with surfactant redosing were identified through logistic regression analysis. Results: Of 1615 consecutive admissions, 662 infants were treated with exogenous surfactant: 462 (70%) received a single dose and 200 (30%) received more than 1 dose (25.5% two doses and 4.5% three doses). Risk of redosing was higher for infants born to mothers with hypertension in pregnancy (OR 3.95, P < .001), for small for gestational age (SGA) infants (OR 3.93, P < .001) and when the first surfactant dose was 100 mg/kg instead of 200 mg/kg (OR 4.56/4.61, P < .001). Infants with greater GA, delayed first surfactant administration, and milder respiratory distress syndrome had reduced risk of redosing. Infants who required multiple surfactant doses had a higher rate of bronchopulmonary dysplasia and mortality, as well as longer duration of respiratory support than patients that received 1 dose. Conclusions: Hypertension in pregnancy and SGA status were found to be statistically and clinically significant predictors of surfactant redosing. Understanding the pathophysiology of these conditions requires further investigation.
