Transfusion therapy in critically ill children

Critically ill children in pediatric intensive care units are commonly indicated for blood transfusion due to many reasons. Children are quite different from adults during growth and development, and that should be taken into consideration. It is very difficult to establish a universal transfusion guideline for critically ill children, especially preterm neonates. Treating underlying disease and targeted replacement therapy are the most effective approaches. Red blood cells are the first choice for replacement therapy in decompensated anemic patients. The critical hemoglobin concentration may be higher in critically ill children for many reasons. Whole blood is used only in the following conditions or diseases: (1) exchange transfusion; (2) after cardiopulmonary bypass; (3) extracorporeal membrane oxygenation; (4) massive transfusion, especially in multiple component deficiency. The characteristics of hemorrhagic diseases are so varied that their therapy should depend on the specific needs associated with the underlying disease. In general, platelet transfusion is not needed when a patient has platelet count greater than 10,000/mm3 and is without active bleeding, platelet functional deficiency or other risk factors such as sepsis. Patients with risk factors or age less than 4 months should be taken into special consideration, and the critical thrombocyte level will be raised. Platelet transfusion is not recommended in patients with immune-mediated thrombocytopenia or thrombocytopenia due to acceleration of platelet destruction without active bleeding or life-threatening hemorrhage. There are many kinds of plasma-derived products, and recombinant factors are commonly used for hemorrhagic patients due to coagulation factor deficiency depending on the characteristics of the diseases. The most effective way to correct disseminated intravascular coagulation (DIC) is to treat the underlying disease. Anticoagulant therapy is very important; heparin is the most common agent used for DIC but the results are usually not satisfactory. Antithrombin III, protein C, or recombinant thrombomodulin has been used successfully to treat this condition. For reducing the risk of organism transmission and adverse reactions resulting from blood transfusion, the following measures have been suggested: (1) replacement therapy using products other than blood (e.g., erythropoietin, iron preparation, granulocyte colony-stimulating factor); (2) special component replacement therapy for specific diseases; (3) autotransfusion; (4) subdividing whole packed blood products into smaller volumes to reduce donor exposure; (5) advances in virus-inactivating procedures. To avoid viral transmission, vapor-heated or pasteurized products and genetic recombinant products are recommended. Cytomegalovirus (CMV)-seronegative blood, leukoreduced and/or irradiated blood are recommended for prevention of CMV infection, graft-versus-host-disease and alloimmunization in neonate and immunocompromised patient transfusion. There is no reason to prescribe a plasma product for nutritional supplementation because of the risk of complications. The principle: complications of transfusion must be avoided, the rate of blood exposure should be reduced and the safety of the transfused agents or components should be maintained must always be kept in mind.