EFFECTS OF SURFACTANTS ON HEMODYNAMICS DU RING NEONATAL RESPIRATORY-DISTRESS SYNDROME

The neonatal respiratory distress syndrome tends to delay the circulat ory adaptation to extra-uterine life and leads to systematic hypotensi on. Haemodynamic changes following the instillation of surfactant are not stereotyped. They depend on the type of surfactant, the time of th e instillation, the degree of prematurity, the severity of the respira tory disease and the mode of instillation. They are characterized by a transient haemodynamic instability with variable consequences on arte rial pressure and systematic blood flow. The use of surfactant tends t o decrease pulmonary arterial resistances and pulmonary arterial press ures but this effect is variable and is not obviously accompanied by l ong-term deleterious effect on the arterial duct. Haemodynamics and bl ood gases changes due to surfactant instillation have a variable effec t on cerebral blood flow. The potential role of blood gas and haemodyn amics changes on the occurence of pulmonary haemorrhage or cerebral da mage following instillation of surfactant remains poorly established b ut has to be taken into account.