Association between route of furosemide administration and diuretic response in very preterm infants with bronchopulmonary dysplasia

OBJECTIVE: Furosemide is commonly prescribed in hospitalized infants with grade 2-3 bronchopulmonary dysplasia (BPD). Intravenous (IV), gastric, and duodenal administrations are common, with a 1:2 IV-to-enteral conversion often used despite uncertain bioavailability. Our objective was to compare diuretic responses between routes in infants with BPD. STUDY DESIGN: Single-center observational cohort of very preterm infants with grade 2-3 BPD prescribed furosemide. The association between route (exposure) and diuretic response (change in net fluid balance after administration, outcome) was evaluated using multivariable regression adjusting for dosing and infant characteristics. RESULTS: Among 153 infants (median postmenstrual age of 43.3 weeks at exposure), furosemide reduced fluid balance by -25.6 (29.8) ml/kg/d. Adjusted mean changes were similar across routes: IV, -25.3 (-35.8, -14.7), gastric, -25.8 (-32.2, -19.4), and duodenal, -25.8 (-34.2, -17.4). CONCLUSIONS: Our data suggest a 1:2 IV-to-enteral conversion leads to comparable diuretic effects in infants with established BPD, supporting this common clinical practice.