Seminars in thrombosis and hemostasis
-
Coagulation factor I (fibrinogen) plays an essential role in the hemostatic system by bridging activated platelets and being the key substrate for thrombin in establishing a consolidating fibrin network. Fibrinogen is synthesized in the liver and the plasma concentration is 1 to 5-4.0 g/L. During recent 10 years, fibrinogen has been recognized to play an important role in controlling hemorrhage. ⋯ This article provides a description of the biochemistry and mechanisms of fibrinogen as well as the etiology for developing fibrinogen deficiency. Furthermore, it summarizes laboratory and experimental data on the role of fibrinogen in dilutional coagulopathy and addresses laboratory monitoring issues. Finally, it lists retrospective and prospective studies, which have been designed to assess the clinical efficacy and safety of hemostatic intervention with fibrinogen concentrate.
-
Semin. Thromb. Hemost. · Apr 2012
ReviewProhemostatic interventions in trauma: resuscitation-associated coagulopathy, acute traumatic coagulopathy, hemostatic resuscitation, and other hemostatic interventions.
Trauma is the most common cause of death in the young and hemorrhage is the most important cause of death in patients with trauma. Recently redefined pathways of inflammation and coagulation, together with hypothermia and acidosis contribute to trauma-associated coagulopathy and aggravation of bleeding. ⋯ Recombinant factor VIIa, fibrinogen and prothrombin complex concentrates, and antifibrinolytic agents have been evaluated in clinical trials. These interventions show promising effects but their efficacy in reducing clinically important outcome parameters need to be confirmed in clinical studies.
-
Surgical procedures of the liver, such as partial liver resections and liver transplantation, are major types of abdominal surgery. Liver surgery can be associated with excessive intraoperative blood loss, not only because the liver is a highly vascularized organ, but also because it plays a central role in the hemostatic system. Intraoperative blood loss and transfusion of blood products have been shown to be negatively associated with postoperative outcome after liver surgery. ⋯ In patients with liver cirrhosis, there is increasing evidence that factors such as portal hypertension and the hyperdynamic circulation play a more important role in the bleeding tendency than changes in the coagulation system. Therefore, intravenous fluid restriction rather than prophylactic administration of large volumes of blood products (i.e., FFP) is recommended in patients undergoing major liver surgery. Pharmacological agents such as antifibrinolytic drugs or recombinant factor VIIa may be indicated in selected individual patients, but these agents do not have a routine role in the management of patients undergoing liver surgery.
-
Pharmacological prohemostatic agents may be useful adjunctive treatment options in patients with severe blood loss. The efficacy of these interventions has been established in a variety of clinical situations. ⋯ Several studies have shown that some prohemostatic interventions may indeed increase the risk of arterial and venous thromboembolism, although these complications are relatively rare. When considering the use of adjunctive prohemostatic agents to prevent or treat excessive blood loss, the risk of thrombotic complications should be taken into account.
-
Obstetric hemorrhage is a major cause of maternal morbidity and mortality. Pregnancy is associated with substantial hemostatic changes, resulting in a relatively hypercoagulable state. Acquired coagulopathy can, however, develop rapidly in severe obstetric hemorrhage. ⋯ Therefore, until efficacy and safety are demonstrated in obstetric hemorrhage, clinicians should be cautious about wholesale adoption of high FFP:RBC ratio products. Applications of transfusion protocols, dedicated to massive obstetric hemorrhage and multidisciplinarily developed, currently remain the best available option. Similarly, while procoagulant agents appear promising in treatment of obstetric hemorrhage, caution is nonetheless warranted as long as clear evidence in the context of obstetric hemorrhage is lacking.