Oral or Poster Presentation
Concurrent Session 3A - Neonatal Clinical Epidemiology
Introduction: Bronchopulmonary dysplasia (BPD) affects nearly 20% of very preterm infants born <33 weeks gestational age (GA). Postnatal fluid adaptation may contribute to risks of BPD. We aimed to investigate the association of 3 indicators of fluid status in the first 10 days after delivery with odds of death and/or BPD among very preterm infants.
Methods: Retrospective cohort study of infants born 23-32 weeks GA admitted to the Montreal Children’s Hospital's NICU 2015-2018. Data was collected from the local Canadian Neonatal Network database and individual chart review. The three independent variables (median serum sodium concentration, cumulative fluid balance and maximum percentage weight loss) were measured over the first 10 days after delivery. Primary outcome was death and/or BPD (oxygen therapy or respiratory support at 36 weeks corrected GA). Unadjusted comparisons were made using the Wilcoxon test. The association of independent variables with outcome was assessed using multivariable logistic regression analyses adjusting for infant characteristics.
Results: Among 439 eligible infants, 125 died and/or developed BPD (29%). Median serum sodium concentration was 139 mmol/L (IQR 136-141) among BPD-free survivors and 136 mmol/L (IQR 134-139) among infants with death and/or BPD (p<0.001). Cumulative fluid balance was 4.09 dL/kg (IQR 2.98-4.78) among BPD-free survivors and 4.88 dL/kg (IQR 3.96-5.95) among infants with death and/or BPD (p<0.001). Maximum % weight loss was 8.5% (IQR 5.4, 11.6) among BPD-free survivors and 9.2% (IQR 4.9, 12.9) among infants with death and/or BPD (p=0.41). In the adjusted analysis (Table 1), only cumulative fluid balance remained associated with odds of death and/or BPD (adjusted odds ratio 1.47, 95% CI 1.11-1.98).
Conclusion: Among very preterm infants, higher cumulative fluid balance in the first 10 days after delivery is associated with higher odds of death and/or BPD. Targeting lower cumulative fluid balance may improve BPD-free survival.