Abstract
Current techniques for measuring oxygenation in newborn infants with respiratory insufficiency are reviewed, as well as the consequences of variable and high fetal hemoglobin (HbF) fractions on both the measurement of sO2 and FCOHb and the application of Siggaard-Andersen's oxygen status algorithm to newborn infants. A procedure involving tonometry of blood is described for measuring FHbF in newborn infants' blood.