Platelets, coagulation and bleeding/thrombotic disorders Flashcards
What happens when primary hemostasis aggregates with other platelets?
Form a surface for coagulation cascade
In secondary hemostasis, what organ makes most coagulation factors?
The liver
3 features of a platelet?
- Anucleated
- Lifespan ~10 days
- Circulating platelets do not adhere-during stasis, adhesion occurs
What is primary hemostasis generally initiated by?
Injury
Primary hemostasis adheres to subendothelium by interacting with what?
von Willebrand factor
In secondary hemostasis, what two things combine to form a stable clot?
Fibrin and platelet aggregates
Secondary hemostasis involves a series of what?
activating enzymatic conversions
In secondary hemostasis, which factors are vitamin k dependant?
Factors II, VII, IX and X
What is an example of a natural anticoagulants and how does it work?
protein C
Prevent growth of clot
What is the purpose of fibrinolysis?
It breaks down clot
What are 3 ways to asses hemostasis?
- Platelet count (part of CBC)
- Coagulation cascade (Prothrombin time-PT and partial thromboplastin time-PTT)
- Fibrinolysis
What might be a reason for prolonged coagulation tests?
deficiency or inhibitor of a coagulation factor
What is a pathological counterpart of hemostasis?
Thrombotic disorders
What 3 things make up “Virchow’s triad”?
Endothelial injury
Abnormal blood flow
Hypercoagulability
6 acquired hypercoagulable states
Surgery/trauma Limb immobilization Bedridden Long-distance air travel Pregnancy Oral contraceptives
3 causes of blood disorders
Abnormal vessels
Decreased platelets/dysfunction
Abnormal factors
What are two causes of platelet-type bleeding?
thrombocytopenia, von Willebrand disease
3 causes of Thrombocytopenia
Decreased bone marrow production
Hemodilution due to multiple transfusions
Immune reaction due to platelet autoantibodies directed at platelet surface proteins
What platelet count might result in spontaneous bleeding?
<10-20,000
What platelet count might result in spontaneous bleeding?
<10-20,000
What kind of drugs can increase bleeding tendency?
Antiplatelet drugs, such as aspirin
What are two inherited abnormalities in coagulation factors?
von Willebrand disease, Hemophilia A and B
What factor is von Willebrand disease associated with?
factor VIII
What are two acquired abnormalities in coagulation factors?
liver disease, vitamin K deficiency
What factors can alter CBC (complete blood count)?
Iron deficiency Medications Alcohol Infections Gender Pregnancy
What is included in your CBC?
red and white blood cells and platelets
What does the leukocyte count include?
all nucleated hematopoietic cells-except red blood cells
White blood count is important in evaluating:
infections, some drug effects, radiation therapy
What is a normal WBC
3500-10,000 cells/microliter
What percent (and total number) of the WBC are neutrophils?
1800-6700 (55%)
What percent (and total number) of the WBC are eosinophils?
0-570 (3%)
What percent (and total number) of the WBC are lymphocytes?
1400-3900 (35%)
Where would your WBC fall if you had leukocytosis?
> 10,000
What are 3 causes of leukocytosis?
Chronic infection or inflammation
Exercise
Some leukemias
(T/F) Microcytic anemia is when you have too many cells
False
Microcytic patients with an iron deficiency often also have what?
Glossitis
What are two causes of microcytic anemia?
Iron deficiency and lead poisoning
(T/F) Macrocytic anemia is when you have too many cells
True
3 causes of macrocytic anemia
Liver disease
Drugs
Vitamin B12 or folate deficiency
Macrocytic patients beacuse of vitamin B12 or folate deficiency often include what other types of symptoms?
neurological (paresthesia, weakness, dementia)
What is leukemia?
systemically distributed neoplasms of white cells
Acute myeloid or lymphatic leukemia shows no evidence of what?
maturation in blood or marrow
In acute myeloid or lymphatic leukemia, what percentage of cells are blast (immature)?
> 20%
What type of leukemia can have skin and gum infiltration?
Acute myeloid or lymphatic
What are lymphomas, and what are the two specific types?
solid tumors of hematopoietic system/neoplasms of lymphoid tissue
Non-hodgkin, and Hodgkin
Which type of lymphoma is curable in most patients?
Hodgkin
What are the characteristics of non-hodgkin lymphoma?
indolent to very aggressive: survival is years to weeks depending on type
Lymphomas usually have (enlarged/reduced), (painless/painful) lymphadenopathy
Enlarged, painless
Both hodgkins and non-hodgkins are __________ ____________ at various developmental stages.
Clonal expansions
Both hodgkins and non-hodgkins are __________ ____________ at various developmental stages.
Clonal expansions
