Thrombocytopenia and critical care medicine

Platelet transfusions play an important role in the treatment of critically ill patients. Like any blood component, however there are various aspects of platelet transfusion therapy that need be considered by the intensivist. These include the proper dose and type of platelet component to infuse, as well as the route and method of administration. Methods to reduce the volu me of the transfused platelets, for example, must ensure that the infused p latelets will be functional and viable, posttransfusion. Treatment and diag nosis of the HLA alloimmunized recipient can pose a serious challenge to th e clinician and an obstacle to adequate platelet therapy An ICU patient for whom an adequate posttransfusion platelet increment cannot be achieved is at great risk of suffering a fatal hemorrhage. The ICU physician should be aware of the techniques used in modern transfusion practice to avoid having to deal with this complication. Adverse reactions to platelet transfusion include not only serologic ones, but those related to febrile and allergic complications, as well as infectious complications. The latter group includ es diseases caused by infection with cytomegalovirus, bacteria, and a cadre of viruses including HIV and hepatitis. The clinical approach to thrombocy topenia in the ICU will be covered in some detail in an effort to review ma ny of the conditions associated with recipient thrombocytopenia, including ITP, TIP, dilutional thrombocytopenia, DIG, surgery, HELLP syn drome, and d rug-induced thrombocytopenia. Unfortunately the treatment approaches tradit ionally used are not always derived from evidence-based studies. This revie w covers many of these topics in an attempt to help physicians become bette r able to manage thrombocytopenia in the ICU and thus provide the best tran sfusion therapy for their patients.