Chlorothiazide is associated with a weaker diuretic response than furosemide in infants with bronchopulmonary dysplasia (BPD)

Objective To compare the diuretic effect of furosemide versus chlorothiazide in preterm infants with high-grade bronchopulmonary dysplasia (BPD). Study Design: We conducted a retrospective cohort study of infants with grade 2 or 3 BPD admitted to a level IV NICU between 36–60 weeks’ postmenstrual age. The primary outcome was within-subject change in net fluid balance (mL/kg) in the 24 hours before and after diuretic initiation. Multivariable linear regression adjusted for differences in diuretic and clinical variables. Results Among 136 furosemide and 215 chlorothiazide exposures in 300 infants, furosemide was most often dosed every 24 hours (73%), while chlorothiazide was most often dosed every 12 hours (90%). Median postmenstrual age at exposure was 44 weeks for furosemide and 42 weeks for chlorothiazide. Furosemide was associated with a significantly greater diuretic effect than chlorothiazide (-32.0 vs. -10.5 mL/kg; p  < 0.001). Conclusions Furosemide resulted in a threefold greater diuretic effect than chlorothiazide in infants with high-grade BPD.