Exchange transfusion is a technique used most often to maintain serum bilirubin at levels below neurotoxicity. Serum levels of bilirubin for which to begin an exchange transfusion are currently under considerable debate (for more details, see Chapters 51 and 92). Exchange transfusions are also used to control other conditions, such as polycythemia or anemia. Three types of exchange transfusion are commonly used: (1) 2-volume exchange, (2) isovolumetric 2- volume exchange, and (3) partial exchange (<2 volumes) with normal saline, 5% albumin in saline, or plasma protein fraction (Plasmanate). These procedures are used primarily in sick newborn infants but may also be used for intrauterine exchanges in fetuses at high risk for central nervous system toxicity (eg, erythroblastosis fetalis) by percutaneous umbilical blood sampling and umbilical vein catheterization under ultrasound guidance.
Hyperbilirubinemia. Exchange transfusions are used in infants with hyperbilirubinemia of any origin when the serum bilirubin level reaches or exceeds a level that puts the infant at risk for central nervous system toxicity (eg, kernicterus) if left untreated (see Table 51–1 and Table 92–3). Two-volume exchange transfusions taking 50–70 min are usually recommended for removal and reduction of serum bilirubin. Efficiency of bilirubin removal is increased in slower exchanges because of extravascular and intravascular bilirubin equilibration.
Hemolytic disease of the newborn results from destruction of fetal red blood cells (RBCs) by passively acquired maternal antibodies. Exchange transfusion aids in removing antibody-coated RBCs, thereby prolonging intravascular RBC survival. It also removes potentially toxic bilirubin from an increased bilirubin load resulting from RBC breakdown and provides plasma volume and albumin for bilirubin binding. Repeated 2-volume exchange transfusions may be needed when RBC destruction is rapid.
Sepsis. Neonatal sepsis may be associated with shock caused by bacterial endotoxins. A 2-volume exchange may help remove bacteria, toxins, fibrin split products, and accumulated lactic acid. It may also provide immunoglobulins, complement, and coagulating factors.
Disseminated intravascular coagulation (DIC) from multiple causes. A 2-volume exchange transfusion is preferred; however, depending on the sick infant's condition, any one of the exchange methods may help provide necessary coagulation factors and help reduce the underlying cause of the abnormal coagulation. Repletion of clotting factors by transfusion of fresh-frozen plasma (10–15 mL/kg) may be all that is necessary in less severe cases of DIC.
Metabolic disorders causing severe acidosis (eg, aminoaciduria with associated hyperammonemia). Partial exchanges are usually acceptable. Peritoneal dialysis may also be useful for treating some progressive metabolic disorders.
Severe fluid or electrolyte imbalance (eg, hyperkalemia, hypernatremia, or fluid overload). Isovolumetric partial exchanges are recommended to prevent large electrolyte fluctuations with each aliquot of blood exchanged. Transfusions with blood products may bind calcium; therefore, calcium gluconate should be available. Fresh blood products should be used to prevent contribution of the by-products of older blood, such as excess potassium.
Polycythemia. It is usually best to give a partial exchange transfusion using normal saline. Plasma protein fraction (eg, Plasmanate) or 5% albumin in saline may also be used; however, normal saline is preferred because it reduces ...
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