OBJECTIVES: To evaluate whether preterm thrombocytopenia within 24 hours of birth is associated with delayed closure of patent ductus arteriosus (PDA) and higher proportion of hemodynamically significant PDA (Hs-PDA).
METHODS: Neonates (gestation 260/7–336/7 weeks, age <24 hours) with known platelet count and PDA on echocardiogram were prospectively enrolled. Asphyxia, congenital infections, structural heart disease, major malformations and clinical sepsis were exclusions. Subjects were recruited in groups A (n = 35), B (n = 18), and C (n = 17) [platelet counts >150,000, 100,000-150,000 and <100,000 per μL respectively] and underwent daily echocardiography until first closure of PDA, death, or day 10.
RESULTS: The primary outcome was time to first closure of PDA. Secondary outcomes included proportion with PDA at 72 hours and 7 days, Hs-PDA, and PDA needing treatment. In groups A, B, and C, median (first–third quartile) platelet counts (×100000/μL) were 2.28 (1.94–3.19), 1.25 (1.14–1.37), and 0.68 (0.54–0.83) and time to PDA closure was 2 (2–2), 2 (2–3), and 10 (6–10) days, respectively (log-rank test, P < .001). On Cox proportional hazard regression, platelet count (in multiples of 10 000 /μL) independently predicted time to PDA closure (adjusted hazard ratio: 1.045; 95% confidence interval: 1.019–1.07). On day 7, 47.1% neonates in group C had PDA and none in groups A and B (P < .001).
CONCLUSIONS: Thrombocytopenia within 24 hours of birth independently predicts delayed PDA closure and PDA on day 7 in preterm neonates.
- Accepted July 25, 2016.
- Copyright © 2016 by the American Academy of Pediatrics