Case–control study of respiratory dynamic compliance in mechanically ventilated near-term newborns in a pre-hospital setting

Abstract

To determine the threshold value between normal or decreased dynamic compliance (Cdyn) in ventilated near-term newborns. A case control study was performed during pediatric transport. Controls were newborns without pulmonary disease (group 1; n=30) and cases were newborns with respiratory distress syndrome, the paradigm of decreased Cdyn (group 2; n=30). All consecutive newborns of more than 34weeks' gestation and less than 5 days of life, intubated and ventilated with Babylog 8,000 plus (Dräger, Lübeck, Germany) were included from February 2008 to June 2010. Newborns were assigned to groups 1, 2, or 3 (other patients with disease where the compliance is not easily predictable) by two physicians, using predefined criteria. Cdyn was as measured by the ventilator in spontaneous mandatory ventilation mode with less than 15% leaks. One hundred and twelve newborns were included in the study. In the multivariate analysis, the groups of diseases and height were statistically associated with Cdyn (p<0.001). The receiver operating characteristic curve of Cdyn corrected for height constructed with group 1 and 2 newborns yielded a cutoff value of 2.02mL/mbar/m with a sensitivity of 100% (95% confidence interval [100-100%]) and a specificity of 96% (95% confidence interval [90-100%]) to differentiate between group 1 and 2 newborns. Ventilator-measured dynamic compliance can differentiate normal and decreased compliance in near-term newborns of more than 34weeks' gestation in the clinical setting.