Ibuprofen lysine administration to neonates with a patent ductus arteriosus: effect on platelet plug formation assessed by in vivo and in vitro measurements.

objectiveIbuprofen might have advantages over indomethacin, when used to effectuate closure of a neonate's patent ductus arteriosus (PDA). Several previous studies indicate that platelet plug formation is impaired after administration of indomethacin, but it is not clear whether a similar impairment occurs following ibuprofen dosing. STUDY

designWe performed template bleeding times and PFA-100 tests (platelet function analyzer) on 20 neonates who had a PDA, before and again at various preset intervals following ibuprofen dosing.

resultPatients ranged from 23 to 40 weeks gestation and weighed 511 to 2566 g. Their first dose of ibuprofen was administered at 72 h (18 to 363 h) after birth (median, range). None of the subjects had clinical bleeding problems noted during the days they received ibuprofen dosing. The template bleeding times before dosing ranged from 135 to 450 s. Repeat tests were performed in groups of four, at 2 h, 4 to 6 h, 12 to 18 h, 24 h after the first dose, and at 2 h after the third dose of ibuprofen. No changes in bleeding times were detected. (P=0.299) A PFA-100 time was performed on all 20 patients before and again after the ibuprofen administration. However, 3 of the 40 tests were unsuccessful, because of microclots in the blood sample (n=1) or failure of the analyzer for an unspecified reason (n=2). Before the dosing the PFA-100 time ranged from 52 to 300 s. A paired t-test showed a slight but statistically significant lengthening in PFA-100 time after the ibuprofen administration (P=0.019). The correlation between the bleeding time and the PFA-100 was poor (R(2)=0.212, P=0.576).

conclusionOn the basis of our present studies, we speculate that ibuprofen lysine administration to neonates with a PDA, when used according to the manufacturer's recommendations, has little adverse effect on platelet plug formation. This information might be a factor to consider when deciding whether to select indomethacin or ibuprofen for PDA closure.