Oxygen needs during resuscitation and surfactant to achieve stabilisation were independent risks factors for pulmonary interstitial emphysema in preterm infants.

AIM: Pulmonary interstitial emphysema is a severe complication of mechanical ventilation in preterm infants that leads to air leakage and, or, chronic lung disease. We determined the associated risk factors.

METHODS: This was a retrospective case-control study from 2005 to 2014 at a regional referral centre in Valencia, Spain. The cases were 54 preterm infants up to 30 weeks' gestation and, or, born weighing less than 1500 g, who were diagnosed with pulmonary interstitial emphysema (PIE). The 54 controls were preterm infants without PIE matched by gestational age. Univariate analysis and multivariate analysis were performed to assess the independent predicting factors.

RESULTS: Infants with PIE had been resuscitated with higher mean fractional inspired oxygen concentration (FiO2 ) (p = 0.008), had received higher peak mean positive end expiratory pressure (p = 0.00) and higher mean airway pressure (p = 0.026) 24 hours before diagnosis. PIE patients also received more surfactant (p = 0.00) and had higher mortality (p = 0.034). A Cox regression model identified that independent risk factors were the total amount of surfactant administered and the mean FiO2 during the 24 hours before diagnosis.

CONCLUSION: Independent risk factors for pulmonary interstitial emphysema in preterm infants were higher oxygen during resuscitation and a higher need for surfactant and ventilatory pressures before diagnosis.