Effects of sodium bicarbonate by rapid injection and of oxygen in high concentration in respiratory distress syndrome of the newborn

Following the rapid intravenous injection of sodium bicarbonate in 19 infants suffering from the respiratory distress syndrome of the newborn (RDS), arterial oxygen tension, arterial oxygen saturation and base excess rose, while arterial carbon dioxide tension and hydrogen ion concentration fell. Effective pulmonary blood flow rose, and right-to-left shunting diminished. Following the administration of increased oxygen to 6 infants with less severe RDS, there was a rise in arterial oxygen tension and a fall in arterial carbon dioxide tension. It is suggested that the changes which occur after both forms of therapy are due to a decrease of pulmonary vascular resistance, reduced right-to-left shunt, and improved pulmonary capillary perfusion.