The effect of double endotracheal administration of Exosurf Neonatal (Wellcome, Great Britain) in a dose of 5 ml/kg on the central and pulmonary hemodynamics, frequency of hemodynamically significant functioning arterial duct (FAD), and lung hemorrhages was studied by Doppler echocardiography in 25 newborns with the respiratory distress syndrome. The hemodynamic parameters were assessed before drug administration, directly and 2 hours after it, and at the age of 1, 2, and 3 days. An unreliable reduction of pulmonary vascular resistance and increase of volumic pulmonary blood flow were observed as soon as during the first minutes after administration of exosurf; this was not paralleled by a pathological increase of the left-right shunting of the blood through patent ductus arteriosus. During the three days that followed the postloading of the right ventricle reliably decreased and the pulmonary bloodflow, cardiac output, and systemic arterial pressure increased. If the traditional measures preventing the possible volumic overloading of the pulmonary circulation in the presence of patent ductus arteriosus were not neglected, administration of exosurf to newborns with the respiratory distress syndrome did not lead to an increase in the frequency of hemodynamically significant FAD and pulmonary hemorrhages.