Physiological aspects of the oxygen treatment of premature infants

Abstract

In order to estimate the degree of respiratory insufficiency, the oxygen consumption of premature infants of different birthweights was determined during the first weeks of life by means of an open circuit system, the details of which will be published later. In the smaller weight classes, there is an increase in the oxygen consumption when the infants breathe oxygen-nitrogen mixtures containing 40-60 per cent oxygen. This increase is less commonly observed and smaller in the higher weight classes of premature infants, and does not occur in healthy full term babies.The oxygen saturation of the blood of prematures increases when the oxygen content of the inhaled air is raised. However, there was no statistical difference between the blood oxygen saturation graphs of premature infants, treated at the hospital, in air or in an incubator, where a 40-60 per cent oxygen mixture was used.A comparison of the volume of trachea-main bronchi and the volume of the lungs in foetuses and prematures weighing from 60 to 3000 grams indicates, that the smaller a foetus or a premature infant the higher the ratio trachea-main bronchi : lungs. DISCUSSION A. YLPPU, PinlandDr. Malm's interesting investigations, which show that an increased supply of oxygen is not bound to produce a rise in the oxygen content of the blood, cannot be interpreted to mean that the oxygen treatment of these premature infants would be of no value. For maximal oxidation of the blood in prematures is dependent on the special character of the blood, and this such that the hemoglobin cannot take up more oxygen. The fact is, however, that if the supply of oxygen is increased, more oxygen will be consumed.