Aim: Studies indicate that reduced foetal haemoglobin levels are related to increased neonatal morbidity rates. This study investigated the relationships between sampling-related blood loss and adult blood transfusions administered during postnatal days 1-14 and the development of severe neonatal morbidities in extremely preterm infants born before 28 weeks of gestation.
Methods: The medical files of 149 extremely preterm infants born at two university hospitals in Sweden from 2013 to 2018 were investigated.
Results: Blood sampling resulted in a 58% depletion of the endogenous blood volume postnatal days 1-14 (median 40.4 mL/kg, interquartile range 23.9-53.3 mL/kg) and correlated with the adult erythrocyte transfusion volume (rS = 0.870, P < .001). Sampling-related blood loss on postnatal days 1-7, adjusted for gestational age at birth and birth weight standard deviation score, was associated with the development of bronchopulmonary dysplasia (BPD) (odds ratio by a 10-unit increase 2.4, 95% confidence interval 1.1-5.4) (P = .03). No associations were found between blood sampling and intraventricular haemorrhage or necrotising enterocolitis in the full statistical model. The largest proportion of sampling-related blood was used for blood gas analyses (48.7%).
Conclusion: Diagnostic blood sampling led to major endogenous blood loss replaced with adult blood components and was associated with the development of BPD.
Keywords: anaemia; blood sampling; bronchopulmonary dysplasia; extremely preterm; transfusion.
© 2019 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.