Late onset of pulmonary hypertension in very low birth weight infants.

INTRODUCTION: Pulmonary hypertension (PH) is a recognized complication of bronchopulmonary dysplasia (BPD). Recent guidelines recommend evaluating all infants with BPD for PH via echocardiogram, but the specific timing of this screening is controversial. We aimed to identify the timing of PH diagnosis in a cohort of very low birthweight infants (VLBW) to determine appropriate age at screening. METHODS: We retrospectively reviewed data on 455 VLBW infants undergoing echocardiography at our institution. The timing of all echocardiograms, PH diagnosis on echocardiography, and BPD diagnosis at 36 weeks corrected age were extracted. PH was defined as dilation of the right sided chambers or RVH, flattening or leftward deviation of the septum, TR >25 mmHg, or 2/3 systemic pressures, or right to left shunting. RESULTS: Fifteen VLBW infants had PH identified on echocardiography, of whom 11 had BPD and 2 died before BPD status at 36 weeks could be ascertained. PH was most often identified on echocardiography after 36 weeks corrected age, and typically around 40 weeks. Ten of the infants ultimately diagnosed with PH had previous echocardiograms performed that were negative for PH at 25-46 weeks. CONCLUSIONS: In our cohort of VLBW infants, onset of PH was typically found later than the 36-38 week range used by recently described screening programs. These findings suggest a need to examine echocardiograms obtained after 36 weeks for evidence of late-onset PH in vulnerable infants born at VLBW.

Relationship between Packed Red Blood Cell Transfusion and Severe Form of Necrotizing Enterocolitis: A Case Control Study.

OBJECTIVE: To determine if packed red blood cell transfusion is associated with onset of necrotizing enterocolitis, and whether withholding feed has any association with it. METHODS: Case records of 100 preterm neonates, (<34 weeks gestation) who developed necrotizing enterocolitis and 99 random age-and gestation-matched controls were evaluated for any blood transfusion 48 h before onset of necrotizing enterocolitis. RESULTS: During the study period 26% infants received packed red blood cell transfusion within 48-hours prior to onset of disease and 84% of these infants were not fed around the time of transfusion. Infants who developed necrotizing enterocolitis after transfusion were older, of lower gestational age, birth weight and more likely to develop stage 3 disease. They had a lower hematocrit at birth and before onset of disease and withholding feeds around transfusion did not prevent necrotizing enterocolitis. Odds of mortality in these infants was 2.83 (95% CI 0.97-8.9) and survivors had no significant difference in incidence of periventricular leukomalacia and length of hospital stay. CONCLUSION: Blood Transfusion associated necrotizing enterocolitis is a severe, mainly surgical form of disease.