Other Hemostasis Disorders

Question 0

What is disseminated intra vascular coagulation?

Answer 0

Pathological activation of the coagulation cascade. Causes widespread microthrombi causing ischemia and infarction. Consumes platelets and factors resulting in bleeding in IV sites and mucosal surfaces.

Question 1

What are lab findings in DIC and how would you treat?

Answer 1

Low platelet count and fibrinogen, high PT/PTT; microangiopathic hemolytic anemia; elevated fibrin split products particularly D dimer. Tx is addressing underlying cause and transfusing blood products and cryoprecipitate as necessary.

Question 2

What 5 items causes DIC?

Answer 2

Secondary to
A. Obstetric complication - tissue thromboplastin activates coagulation
B. Sepsis - endotoxins from bacteria and cytokines induce tissue factor production
C. Adenocarcinoma - mucin activates coagulation
D. Acute promyelotic leukemia - primary granules activate coagulation
E. Rattlesnake bite - venom activates coagulation

Question 3

How is thrombus removed after damaged vessel heals?

Answer 3

tPA converts plasminogen to plasmin. Plasmin cleaves fibrin and serum fibrinogen, destroys coagulation factors and blocks platelet aggregation. Alpha2 anti plasmin inactivates plasmin.

Question 4

What are two examples of disorders of fibrinolysis due to plasmin over activity and how do they manifest?

Answer 4

A. Radical prostatectomy - release of urokinase activates plasmin
B. Cirrhosis leads to reduced production of alpha 2 anti plasmin

Question 5

What are lab findings in fibrinolysis disorders and what is the treatment ?

Answer 5

• Increased PT/PTT because plasmin destroys coagulation factors
• Increased bleeding time with normal platelet count - plasmin blocks platelet aggregation
• Increased fibrinogen split products without D dimers because yet here are no fibrin thrombi to serve as its source
  Tx is aminocaproic acid which blocks activation of plasminogen