Transfusion therapy in the intensive care unit

Transfusion therapy in the intensive care unit is an ever-growing field, with new understanding of potential complications, new drug therapies to reduce the need for transfusion, and new additions in component therapy. In addition to the risks of sepsis, ABO blood group mismatch, and other complications associated with transfusion, the intensivist needs to be familiar with alternative therapies to minimize transfusion.

Transfusion-related acute lung injury and immunosuppression are two newly recognized complications in transfusion. Transfusion-related acute lung injury can lead to respiratory failure in an acute respiratory distress syndrome-like picture, often necessitating intubation and critical care services. Immunosuppression following transfusion has been linked to cytokine and complement activation. Recombinant erythropoietin (rHuEPO, Epogen, Procrit), by maximizing red cell counts, and aprotinin (Trasylol), by inhibiting fibrinolysis, are two old drugs being used with increasing frequency in a new setting: the intensive care unit. A new component therapy, recombinant factor VIIa (rFVIIa, NovoSeven), assists in turning on the extrinsic pathway of the coagulation cascade.

Recognizing early signs of transfusion-related acute lung injury may aid in the treatment and reporting of this entity. Realizing the mechanism and severity of immunosuppression associated with transfusion may alter transfusion triggers in the intensive care unit. rHuEPO and aprotinin are now being used with increasing frequency to increase red cell counts and minimize the need for transfusion. Recombinant factor FVIIa targets coagulation cascade activation which helps to reduce the number of units of blood products transfused in the actively bleeding patient.