EARLY CORRECTION OF HYPOXEMIA AND ACIDEMIA IN INFANTS OF LOW BIRTH WEIGHT: A CONTROLLED TRIAL OF OXYGEN BREATHING, RAPID ALKALI INFUSION, AND ASSISTED VENTILATION

Abstract

Twenty low-birth-weight infants showing hypoxemia and acidemia during the first hours of life were treated with contrasting policies of environmental oxygen exposure, correction of blood pH with sodium bicarbonate, and ventilatory assistance. Results were evaluated by clinical, physiologic, and radiologic observations, mortality during the first 7 days of life, and neurologic follow-up of survivors (study in progress). The course of the arterial oxygenation defect was assessed by serial measurements of arterial oxygen tension (pa02) during 100% oxygen breathing. On admission, the lower the pH, the greater was the calculated percent right-to-left shunt. In comparison to pa02 while breathing 50% oxygen, pa02 during administration of 100% oxygen rose more than could be accounted for by a change in calculated alveolar oxygen tension, i.e., calculated right-to-left shunt fell. This effect was not demonstrably modified by randomly manipulated concurrent correction of pH by rapid infusion of bicarbonate or by assisted ventilation. Within the limits of the study, the acute effect of hypoxemia and of oxygen breathing were more apparent than those of acidemia or its correction. However, no significant differences in early mortality could be related to variations in treatment.