Acquired Flashcards
What is defined as a massive blood transfusion?
Transfusion of one’s entire blood volume within 24 hours, transfusion of half (50%) of total blood volume in 3 hours, transfusion of >10 units of packed red cells in 24 hours, or transfusion of >4 units in 1 hour.
What deficiencies are typically found in stored blood?
Deficient in platelets and some coagulation factors (F V and VIII).
What causes haemostatic defects in massively transfused patients?
Dilution of platelets and coagulation factors.
What is the major role of the liver in haemostasis?
Synthesizes coagulation factors and natural anticoagulants, utilizes vitamin K for synthesis of vitamin K dependent proteins, and clears activated coagulation factors and plasminogen activators.
What are common causes of bleeding in liver disease?
- Oesophageal varices (portal hypertension)
- Thrombocytopenia
- Deficient synthesis of coagulation factors
- Deficient utilization of vitamin K
- Disseminated intravascular coagulation (DIC)
- Increased fibrinogenolysis
- Defective platelet function
- Synthesis of defective fibrinogens.
What laboratory findings are associated with liver disease?
- Prolonged PT
- Prolonged APTT
- Prolonged TT
- VWF normal
- Low platelet.
What management strategies are recommended for liver disease-related bleeding?
- Fresh frozen plasma
- Prothrombin complex concentrate
- Supply vitamin K dependent factors
- Vitamin K
- Fibrinolytic inhibitors if no DIC.
What is Vitamin K deficiency bleeding (VKDB)?
A condition where levels of vitamin K-dependent clotting factors are depressed in newborns, leading to bleeding.
What are the presentations of early, classical, and late VKDB?
- Early VKDB: First 24 hours of life
- Classical VKDB: Days 2-7 of life
- Late VKDB: Day 8 to 6 months of life.
What causes early VKDB?
Infants of mothers on vitamin K-inhibiting drugs.
What is the diagnostic criterion for VKDB?
A Prothrombin Time (PT) more than four times control with a normal platelet count, normal fibrinogen level, and absent fibrinogen degradation products.
What are the treatment options for VKDB?
Prophylaxis with oral vitamin K, IV vitamin K for active bleeding, and monitoring PT correction.
What is the role of vitamin K in the body?
Vitamin K is a fat-soluble vitamin essential for synthesizing certain coagulation factors.
What are common causes of vitamin K deficiency?
- Haemorrhagic disease of the newborn
- Poor dietary intake
- Impaired absorption
- Drugs like anticoagulants (e.g., Warfarin)
- Broad-spectrum antibiotics.
What are specific inhibitors in coagulation disorders?
Antibodies that inhibit the activity of specific coagulation factors, including FVIII, FIX, fibrinogen, and von Willebrand factor.
What is Acquired Haemophilia A?
A rare autoimmune bleeding disorder due to auto-antibodies against endogenous FVIII.
What are the clinical manifestations of Acquired Haemophilia A?
- Widespread subcutaneous bleeding
- Haematomas
- GI and GU bleeding
- Neurovascular compression may be limb-threatening.
What is the pathogenesis of disseminated intravascular coagulation (DIC)?
Involves a fibrinolytic defect and the role of cytokines, with sepsis being the most common trigger.
What laboratory findings are indicative of acute DIC?
- Prolonged PT, APTT, and TT
- Reduced fibrinogen level
- Increased D-Dimers/FDP
- Reduced platelet count.
What is the treatment for lupus anticoagulant?
Long-term anticoagulant therapy is frequently required in patients with thrombosis.
What are the types of antiphospholipid antibodies?
- Anticardiolipin antibodies
- Anti-b2-glycoprotein I antibodies
- Lupus anticoagulant.
What are common laboratory findings in chronic DIC?
- PT, APTT normal
- Platelet count normal
- FDP and D-dimer increased.
What is acquired von Willebrand syndrome associated with?
An autoantibody, typically in the context of monoclonal gammopathy or other hematological disorders.
What is the significance of the presence of proteins induced by vitamin K absence or antagonism (PIVKA)?
It is a marker of subclinical vitamin K deficiency.
