Complications of Transfusion Therapy

Although the administration of blood products can be lifesaving, a number of potential complications should be anticipated (also see Chapter 47 ). Whenever massive transfusion therapy is used, the risks of citrate toxicity, transfusion reactions, and leukocyte and platelet sensitization must be kept in mind. In addition, depending on the age and type of blood component being administered, electrolyte disturbances such as hypocalcemia, hyperkalemia, and hypernatremia can occur. Whenever in doubt, a sample of the infusate should be sent for electrolyte analysis, and the patient's serum values of electrolytes and ionized calcium should be monitored during therapy.^[317] Transfusion-acquired infections, including hepatitis, cytomegalovirus, and acquired immunodeficiency syndrome, have decreased with improvement in the screening of blood donors and extensive testing of units of blood.^[318]

Finally, hemochromatosis complicates the care of patients who require long-term transfusion therapy for the treatment of an RBC abnormality. Efforts designed to decrease this often lethal complication include aggressive iron chelation therapy and the selective transfusion of young RBCs in an attempt to increase the time interval between required transfusions.^{[319] [320]}

In addition to RBC loss and abnormal oxygen binding, grossly deformed RBCs can cause vaso-occlusive disease. Sickle cell anemia is the best example of this pathophysiology. Sickle cell anemia is a hemoglobinopathy. The major ICU complication is vaso-occlusive disease, which can be manifested as a painful crisis; if vaso-occlusion occurs in the cerebral vessels or in another vital organ supply, it can be manifested as stroke or infarction.^[321] Vaso-occlusive disease of the lung is referred to as acute chest syndrome and is clinically manifested as ARDS. Treatment consists of hydration, oxygen, and when severe, exchange tranfusion and mechanical ventilation.^[322] The other potentially fatal crisis of sickle cell disease is splenic sequestration, which occurs in infants and young children who have not undergone autosplenectomy. Splenic sequestration is manifested as severe anemia and hypovolemic shock. Treatment consists of aggressive supportive therapy with emergency surgical splenectomy.^[323] Other children with sickle cell disease have usually had a functional autosplenectomy from multiple splenic infarcts. These "splenectomized" children are at risk for severe infection from encapsulated organisms. Routine pneumococcal vaccine is administered as a precaution.^[324]