Early haemodynamically significant patent ductus arteriosus does not predict future persistence in extremely preterm infants

Abstract

Aim: We assessed whether early haemodynamically significant patent ductus arteriosus (hsPDA) predicted persistent patent ductus arteriosus (PDA) in extremely preterm infants.

Methods: This prospective observational study of 60 infants born at 22-27 weeks of gestational age (GA) without any major congenital anomalies or heart defects was conducted at Uppsala University Children's Hospital from November 2012 to May 2015. Respiratory and systemic circulatory parameters were continuously recorded, and echocardiographic examinations performed daily during the first three days of life. Pharmacological treatment was initiated if hsPDA was found on days two to seven. Persistent PDA was diagnosed if hsPDA remained after pharmacological treatment or pharmacological treatment was contraindicated.

Results: The infants (56% male) had a median GA of 25 + 2 weeks and 50% received pharmacological treatment. PDA was persistent in 30% and ultimately closed or insignificant in 70%. hsPDA on days two to seven was not associated with future persistent PDA (p = 1.000). Mechanical ventilation (p = 0.025), high mean airway pressure (p = 0.020) and low ductal maximal flow velocity (V_max ) (p = 0.024) on day two were associated with future persistent PDA.

Conclusion: Early hsPDA did not predict persistent PDA, but the early need for assisted ventilation and low ductal V_max were associated with future persistent PDA in these extremely preterm infants.

Keywords: Ductal flow velocity; Echocardiography; Extremely preterm infant; Haemodynamical significance; Patent ductus arteriosus.