Advances in the theory and practice of exchange transfusions.

In the management and prevention of hemolytic disease of the newborn, exchange transfusions seem destined to remain the mainstay of therapy for some time to come. Our current knowledge of bilirubin metabolism has altered the indications for the procedure and introduced such useful new adjuncts to therapy as albumin infusions. The decision to do an exchange transfusion cannot be made by any one rule, but must be individualized for each patient and take into account all the factors known to influence the risks of bilirubin toxicity and the exchange procedure. A thorough evaluation of the infant's condition, particularly his cardiorespiratory and metabolic status (including blood pH, gas and albumin determinations), will provide valuable information as a guide to therapy. The limited capacity of some newborn infants to make adequate physiological adaptations to a variety of stresses imposed by the procedure influences the preparation of donor blood, the rate and volume of exchange and the time at which it should be done.A clear understanding of the mechanics of the exchange and the distribution of indirect bilirubin within the body will permit more accurate prediction of what can be accomplished in bilirubin removal and correction of hematocrit with exchanges of different volumes. When weighing the risk of kernicterus against that of exchange transfusion, the experience of the operator and the availability of suitable facilities cannot be ignored.