Early respiratory system mechanics and the prediction of chronic lung disease in ventilated preterm neonates requiring surfactant treatment.

The objective of this study was to evaluate the predictive value of the respiratory system compliance (Crs) and resistance (Rrs) measured before surfactant therapy to identify infants at risk for chronic lung disease (CLD). Measurements of Crs and Rrs were obtained on 44 ventilated neonates with respiratory distress syndrome (RDS) before and after surfactant therapy using the passive expiratory flow-volume method. It was found that in addition to a lower gestational age (GA) and a lower birth weight (BW), infants with CLD (n = 10) exhibited a lower Pa/AO(2) [Pa/AO(2) = PaO(2)/(PiO(2) - PaCO(2))] and higher Rrs before surfactant compared to the infants without CLD (n = 28). Improvement in gas exchange 18 h after surfactant was reduced in the CLD group. Finally, we concluded that a low GA (< 28 weeks), a low BW (< 942 g), a low Pa/AO(2) before and 18 h after surfactant or a high Rrs before surfactant (>0.21 cm H(2)O/ml/s) were associated with an increased risk of CLD. Copyright 2003 S. Karger AG, Basel