Diffusion of carbon monoxide in the lungs and pulmonary artery pressures in school aged children who were born preterm

Abstract Background Premature birth is associated with altered pulmonary vascular development and raised pulmonary artery pressures (PAPs). Arrested alveolar and vascular development reduce lung surface area, which can be assessed by the diffusion capacity of the lung for carbon monoxide (DLCO) and the carbon monoxide transfer coefficient (K CO ). We hypothesise that abnormal DLCO and K CO would be associated with higher PAPs in school-aged children Methods We enroled participants born premature ( < 29 weeks gestation) from the United Kingdom Oscillation Study and age-matched term-born children. Echocardiography was performed, including estimates of systolic and mean PAP (SPAP and MPAP) and spirometry and DLCO measurements were made. An abnormal result was Z score