INTRODUCTION
Patent ductus arteriosus (PDA) is a common morbidity in extremely
preterm infants. Failure of ductal closure has been associated with many
severe morbidities, including broncopulmonary dysplasia (BPD),
intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC) and
mortality [1-4], but there is lack of evidence for a
cause-and-effect relationship [5]. Practices in PDA management are
not consistent among institutions ranging widely from universal
prophylactic treatment to selective treatment on the basis of various
clinical criteria, to no treatment at all [6].
The majority of extremely preterm infants receive invasive mechanical
ventilation (IMV) to maintain oxygenation and ventilation [7] and
prolonged IMV has been associated with an increased risk of mortality
and neonatal morbidities, including upper airway injury, nosocomial
infections and BPD [8-10]. Failed extubation is also independently
associated with increased risk of mortality, BPD, severe IVH, longer
hospitalization, more days on respiratory support and significant
respiratory setback lasting multiple days after
re-intubation.[11-15]
There have been reports of an association between presence of PDA and
extubation failure in preterm infants [16, 17]. Limitations of these
studies include small sample size (9 out of 39 infants [16] and 22
out of 82 infants [17]) with extubation failure, lack of use of
Nasal Intermittent Positive Pressure Ventilation (NIPPV) prior to
re-intubation [17] and lack of data on the timing of diagnosis of
PDA.
The objective of the current study was to evaluate the association
between a hemodynamically significant PDA and failure of first elective
extubation among extremely low birth weight infants.