ARTERIOVENOUS ECMO FOR NEONATAL RESPIRATORY SUPPORT - STUDY IN PERIGESTATIONAL LAMBS

Abstract

Neonatal respiratory support by arteriovenous perfusion was studied. Perigestational lambs delivered by cesarean section were the respiratory distress animal models. Arteriovenous flow was accomplished between a single umbilical artery and vein. A microchannel membrane oxygenator provided partial respiratory support to the newborn lambs. Total systemic flow, pulmonary blood flow and pulmonary vascular resistance were assessed at various rates of arteriovenous perfusion and correlated with systemic oxygenation. A reduction in right-to-left shunting of blood and pulmonary vascular resistance occurred as arterial oxygenation rose from conditions of hypoxemia to PaO2 [O2 arterial partial pressure] values higher than 50 torr. ECG tracings, pulmonary capillary wedge pressures and central venous pressures showed that myocardial performance was not impaired at rates of arteriovenous perfusion below 30% of the total systemic flow. Arteriovenous extracorporeal membrane oxygenation (ECMO) may be suitable for use in infants with hypoxia and high pulmonary vascular resistance.