B-type natriuretic peptide concentrations to guide treatment of patent ductus arteriosus

To determine whether b-type natriuretic peptide (BNP) concentrations can guide treatment of patent ductus arteriosus (PDA) to reduce the number of indomethacin doses without increasing morbidity.

Prospective, randomised, controlled trial.

Single-centre referral neonatal intensive care unit.

Infants with echocardiographic diagnosis of PDA. Infants with congenital heart disease or renal insufficiency were excluded.

BNP measurement and echocardiography were performed in all subjects before and after indomethacin treatment. The investigational group had BNP concentrations measured 12 and 24 h after the first dose (before the 2nd and 3rd doses of indomethacin). Indomethacin dosing was withheld in the BNP-guided group if the 12 or 24 h BNP concentrations were found to be <100 pg/ml.

Number of doses of indomethacin given during the primary course of treatment (three doses every 12 h).

Sixty patients were randomly assigned to control (n = 30) and BNP-guided (n = 30) treatment groups. There was no difference between the groups with respect to gestational age (26(+3) vs 25(+5) weeks, respectively), Apgar scores, delivery method, gender or indomethacin prophylaxis. Median baseline and 48 h BNP concentrations did not differ between the groups (0 h: 500 vs 542 pg/ml; 48 h: 85 vs 126 pg/ml; control and BNP-guided groups, respectively). During primary indomethacin treatment, the BNP-guided group received fewer doses of indomethacin than controls (70 vs 88 doses, p<0.05). The rate of PDA ligation, intestinal perforation and chronic lung disease did not differ between groups.

BNP-guided treatment reduced the number of primary indomethacin doses. There was no increase in PDA persistence or associated morbidity.