The role of exchange transfusions in the management of low-birth-weight infants with and without severe respiratory distress syndrome. II. Further observations and studies of mechanisms of action.

Exchange transfusion, as a form of therapy, was contrasted with the use of fresh frozen plasma or conventional supportive care alone in the management of 19 infants with birth weights of less than 1,000 gm, without severe respiratory distress, and in the management of 82 infants, birth weights less than 2,000 gm, with severe respiratory distress whose disease manifested itself within the first 24 hours of life. Survival for more than five days was similar, regardless of therapy, in infants weighing less than 1,000 gm without severe RDS. In contrast, the use of exchange transfusion significantly decreased the case fatality rate of infants with severe RDS. In the groups receiving exchange transfusion, the mortality rate was 41%, whereas the groups receiving either plasma or supportive care alone the mortality was 80%. Study of coagulation factors and red cell concentrations of fetal hemoglobin and of 2,3-DPG failed to demonstrate any relationship between either improvement in coagulation or oxygen unloading and the improved survival of infants receiving exchange transfusion. Following exchange transfusion there was a significant decrease in the ratio of FIO2 to PaO2, suggesting that pulmonary perfusion and/or ventilation was improved by the procedure.