This is a prospective observational study in 20 neonates (gestation<28 weeks) undergoing early extubation. Echocardiography was performed 5 min pre-extubation and 20 min post-extubation to continuous positive airway pressure. Normal cardiac anatomy was ascertained. Left pulmonary artery (LPA) and ductus arteriosus diameter and flows were recorded. Doppler spectral pattern of velocity was recorded over a minimum of four cycles.