Transfusion
-
Hemoglobin-based oxygen carriers (HBOCs) are thought to have an adverse risk:benefit profile when compared to that of transfusing stored red blood cells (RBCs). However, there are clinical circumstances when RBC transfusion is not an option (e.g., patient refusal, unavailability owing to issues of compatibility or remote location). ⋯ We conclude that at Hb concentrations less than 6 g/dL, the risk of a further decrease in Hb concentration greatly exceeds the risk of HBOC infusion. Thus, we suggest that there may be a place for use of HBOCs when RBC transfusion is not an option.
-
Factor XIII (FXIII) is activated by thrombin to form a transglutaminase (FXIIIa) that stabilizes clot formation by the cross-linking of fibrin monomers and antifibrinolytic proteins. Although rare, FXIII deficiency is characterized by variable bleeding manifestations depending on the magnitude of the deficiency. A congenital FXIII deficiency with levels less than 1% can be detected in children who present with prolonged bleeding from the umbilical stump as well as protracted bleeding after trauma. ⋯ Genetic studies have identified a wide range of mutations that affect the activity of the FXIII protein but in lieu of molecular genetic analyses, FXIII deficiency can be identified by specific diagnostic assays that measure either the transglutaminase activity of the protein or the levels of the protein and its individual subunits. Replacement therapy has also been shown to increase FXIII levels and reduce bleeding symptoms in patients with congenital FXIII deficiency. This review presents recent findings on the biology of FXIII and the clinical manifestations observed among patients with congenital and acquired FXIII deficiencies.
-
Review Case Reports
How do I allocate blood products at the end of life? An ethical analysis with suggested guidelines.
Blood products are scarce resources requiring prudent and reasoned allocation. The utilization of red blood cells and platelets in terminally ill patients can be complicated and requires guidelines tempered by individualized considerations. ⋯ Relevant literature is reviewed and ethical issues pertaining to each case are discussed. A practical approach to blood product utilization at the end of life is suggested.
-
Coagulopathy related to massive bleeding has a multifactorial aetiology. Coagulopathy is related to shock and blood loss including consumption of clotting factors and platelets and hemodilution. Additionally hyperfibrinolysis, hypothermia, acidosis, and metabolic changes affect the coagulation system. The aim of any hemostatic therapy is to control bleeding and minimize blood loss and transfusion requirements. Transfusion of allogeneic blood products as well as the presence of coagulopathy cause increased morbidity and mortality. ⋯ Future treatment of coagulopathy associated with massive bleeding can be based on an individualized point-of-care guided rational use of coagulation factor concentrates such as fibrinogen, prothrombin complex concentrate, and recombinant factor VIIa. The timely and rational use of coagulation factor concentrates may be more efficacious and safer than ratio-driven use of transfusion packages of allogeneic blood products.
-
With the advent of remote damage control resuscitation and far-forward surgery, a renewed emphasis has been placed on examining a variety of pharmacologic adjuncts to controlling blood loss before definitive operative intervention. In this paper, the authors review the current state of the art for tranexamic acid (TXA) and its potential benefits to those patients who are in need of a massive transfusion. Specifically addressed are its biologic and pharmacologic properties, as well the results of a number of recent studies. ⋯ The 2012 Military Application of Tranexamic Acid in Trauma Emergency Resuscitation study provided a retrospective analysis of 896 wounded cared for at a military hospital in Afghanistan. This study demonstrated a 23.9%-17.4% reduction in all-cause mortality. Finally, they discuss the potential complications associated with TXA use as well as areas of future research, which are needed to solidify our knowledge of TXA and its potential beneficial effects on controlling bleeding.