Chapter 26: Coagulation Disorders

Coagulation Disorders examination of coagulation disorders details the intricate mechanisms and clinical management of both inherited and acquired haemostatic deficiencies. The text prioritizes major hereditary conditions, starting with Haemophilia A and B, which are sex-linked traits involving deficiencies in clotting factors eight and nine respectively. These conditions typically manifest through painful joint bleeds and muscle haematomas, which can lead to permanent physical disability without appropriate intervention. Modern management has evolved from simple factor replacement to include long-acting recombinant proteins, bispecific monoclonal antibodies like emicizumab that bypass factor requirements, and pioneering gene therapies using viral vectors to achieve long-term factor expression. The discussion extends to Von Willebrand Disease, recognized as the most prevalent inherited bleeding disorder, which impairs platelet adhesion and protection of factor eight, primarily causing mucous membrane and post-operative bleeding. Beyond these, the chapter explores rare factor deficiencies and a wide spectrum of acquired conditions. Vitamin K deficiency is highlighted for its critical role in the functional synthesis of procoagulant proteins, particularly in neonates or patients experiencing malabsorption or using anticoagulant medications like warfarin. The complex pathophysiology of Disseminated Intravascular Coagulation (DIC) is explored as a systemic crisis where the overactivation of thrombin leads to widespread microvascular thrombosis and severe consumptive haemorrhage, often triggered by sepsis, trauma, or malignancy. Furthermore, the clinical challenges of liver disease are addressed, where the failing organ cannot synthesize necessary clotting factors, creating a precarious balance between bleeding and thrombosis. The summary also covers massive transfusion protocols, emphasizing the necessity of balanced blood product replacement to avoid dilutional coagulopathy. Advanced near-patient monitoring techniques, specifically thromboelastography (TEG) and ROTEM, are explained as vital tools for real-time assessment of clot strength and stability during surgery or trauma. Finally, the presence of acquired inhibitors, such as autoantibodies against factor eight or the prothrombotic lupus anticoagulant, provides essential insight into immune-mediated coagulation dysfunction.