B-Type Natriuretic Peptide Predicts Responses to Indomethacin in Premature Neonates with Patent Ductus Arteriosus. Journal of Pediatrics - Volume 157, Issue 1 (July 2010)

Mean baseline BNP levels were higher in neonates who were non-responders (2234 ± 991 pg/mL) than neonates who were responders (983 ± 814 pg/mL; P = .001). A baseline BNP level >1805 pg/mL had a sensitivity rate of 88% and a specificity rate of 87% for predicting indomethacin non-responsiveness (P = .003).

This was an interesting study shedding some light on the response of PDA to indomethacin.