The relationship between early postnatal arterial blood values and moderate and severe bronchopulmonary dysplasia in preterm infants

Objective To study the relationship between arterial blood pH, PaO₂, and PaCO₂ in the first week after birth and moderate and severe bronchopulmonary dysplasia (BPD) in preterm infants.

Methods A cohort of 236 consecutive preterm infants with < 32 gestational weeks were selected from January of 2017 to December of 2019, 54 infants with moderate and severe BPD were identified as the study group and the other as the control group. Early blood gas values and clinical characteristics were collected and analyzed.

Results Compared with the control group, significantly lower pH (7.25±0.12 vs 7.31±0.09, P=0.001) of 1st day, lower PaO₂ (63.20±23.75 mmHg vs 75.91±20.70 mmHg, P < 0.001), higher PaCO₂ (43.59±9.87 mmHg vs 38.26±9.11 mmHg, 1 mmHg=0.133 kPa, P < 0.001) of 7th day occurred in the study group. Lower pH of 1st day and lower PaO₂ of 7th day after birth were the independent risk factors of moderate and severe BPD besides lower gestational age, lower birth weight, and mechanical ventilation.

Conclusions The early hypoxia and acidosis after birth may affect the progress of moderate and severe BPD.