Feeding preterm neonates with patent ductus arteriosus (PDA): Intestinal blood flow characteristics and clinical outcomes

Objective: To evaluate the effects of patent ductus arteriosus (PDA) on postprandial superior mesenteric artery blood flow velocities (SMA BFV)s and feeding tolerance in extremely low birth weight (ELBW) neonates. Methods: Appropriate for gestational age, ELBW preterm neonates, tolerating bolus enteral feedings were eligible to participate in this prospective observational study. Pulsed Doppler was used to measure preprandial and postprandial (at 30 and 60min) time-averaged mean velocity (TAMV), peak systolic velocity (PSV) and end diastolic velocity (EDV) once during the day of life 5-7; at the same time, PDA size was estimated using the PDA: left pulmonary artery (LPA) ratio. Results: A total of 38 infants were studied, 16 in small, 13 in moderate and 9 in large PDA groups. The postprandial SMA BFVs were lower in the large PDA group, although not reaching statistical significance. Importantly, infants in the large PDA group reached full enteral intake later (p=0.02) and had higher incidence of death secondary of necrotizing enterocolitis (NEC; p=0.04). Conclusions: ELBW preterm neonates with large PDA may have attenuated intestinal blood flow responses to feedings. There was also an association with higher rates of necrotizing enterocolitis and feeding intolerance in the large PDA group.