Lecture Hematological/Blood Clotting (Quiz 4) Flashcards
Hemostasis (or the clotting of blood) has a Primary and a Secondary factor. What makes them different? With Secondary Hemostasis, what are the Factors and how is it Measured for each of the 3 Pathways? What are the Factors involved with Fibrin and Platelet aggregation of a clot with Secondary Hemostasis and what makes them unique?
- Primary Hemostasis: Platelets. Typically initiated by injury, Aggregate with other platelets and form surface for coagulation cascade, Adherence to subendothelium by interacting with Von Willebrand Factor (carrier for Factor VIII).
- Secondary Hemostasis: Factors that cause the adhesion/coagulation for platelets. Coagulation cascade (factors mostly from liver), Has an Intrinsic, Extrinsic and Common Pathways. Fibrin and Platelet aggregates form stable clot.
- Secondary Hemostasis Pathway:
(a) Intrinsic pathway (XII, XI, IX, VII factors)- measured by PTT clotting time.
(b) Extrinsic pathway (VII, IX factors)- measured by PT clotting time.
(c) Common (factors X,V,II, & fibrin production)-measured by both PTT and PT clotting times. - Factors II, VII, IX and X are vitamin K-dependent, they are necessary for calcium binding sites activating coagulation cascade.
What are some features of Platelets?
- Anucleated
- Lifespan ~10 days
- Circulating platelets do NOT adhere. During stasis, adhesion occurs
What are natural anticoagulants and prevent clotting? What breaks down clots?
- Protein C
- Fibrinolysis
How do you assess Hemostasis?
- Platelet count (part of CBC)
- Coagulation cascade (Prothrombin time-PT and partial thromboplastin time-PTT, used for Pathway discovery)
- Prolonged coagulation tests may be due to deficiency or inhibitor of a coagulation factor.
What disorder is the pathologic counterpart of hemostasis, and results in abnormal clotting? This causes Virchow’s Triad, what is this triad? Hypercoagoagulation of blood can be acquired, what are some examples where this can happen? Another way to get a Thrombotic is through genetics. What is an example of a genetic thrombotic disorder and what does it cause?
- Thrombotic (Thrombosis) disorders
- Endothelial injury, Abnormal blood flow, and Hypercoagulability (acquired/inherited factors)
- Acquired hypercoagulable states: Surgery/trauma, Limb immobilization, Bedridden, Long-distance air travel, Pregnancy and Oral contraceptives.
- Factor V Leiden Mutation: Most common inherited thrombophilia- associated with increased fibrin formation, Increased clotting but usually not a major problem, and Found in 5% adults/quite common.
What are common causes for bleeding disorders? With Platelet-Type bleeding or Mucocutaneous bleeding, what are typical causes for this?
- Abnormal vessels, Decreased platelets/dysfunction and Abnormal factors.
- Thrombocytopenia (reduced bone marrow production) and Von Willie Brand Disease (mutated factor VIII carrier protein)
What can be caused due to Decreased bone marrow production, Hemodilution due to multiple transfusions, and Immune reaction due to platelet autoantibodies directed at platelet surface proteins? Clinically how does this present?
- Thrombocytopenia
- Platelet count is
What are the two Inherited abnormalities in coagulation? What are two Acquired abnormalities in coagulation?
- Inherited: Von Willebrand Disease (factor VIII) and Hemophilia A/B (more likely in males due to X-recessvie trait)
- Acquired: Liver disease and Vitamin K deficiency.
What has generalized secondary activation of clotting due to Disseminated Factors such as Toxins (e.g. rattlesnake venom), Inflammation, Cancers etc., can cause both Organ Ischemia because of Increased Clotting as well as Bleeding due to Increased activation of Fibrolysis?
- Disseminated Intravascular Coagulation (DIC)
What is counted in a CBC (complete blood count)? What 6 things can alter the CBC count? What is counted in a WBC (White blood count)? What is a normal WBC? What are the range AND percentages of normal WBC levels of Neutrophils, Eosinophils, and Lymphocytes **(Be familiar with the percentage to be able to do the math for a safe level)? What is a WBC disorder that is caused by: Chronic infection or inflammation, Exercise, and Some leukemias? What WBC levels will be considered Leukocytosis?
- Red and white blood cells and platelets
- Iron deficiency, Medications, Alcohol, Infections, Gender and Pregnancy.
- Leukocyte count include all nucleated hematopoietic cells-except red blood cells.
- 3,500-10,000 white blood cells/microliter
- Neutrophils: 1,800-6,700 (55%)
Eosinophils: 0-570 (3%)
Lymphocytes: 1,400-3,900 (35%) - Leukocytosis
- WBC is greater than (>) 10,000/ul.
What is a condition in which the blood doesn’t have enough healthy red blood cells? There are two types of of this, Microcytic and Macrocytic, what makes them different?
- Anemia
a. Microcytic (too few cells):
• Iron deficiency (most often caused by hemorrhaging)-often has glossitis
• Lead poisoning
b. Macrocytic (too many cells):
• Liver disease
• Drugs
• Vitamin B12 or folate deficiency-often includes neurological findings (paresthesia, weakness, dementia)
What is a systemically distributed neoplasms (abnormal growth) of white cells? There are two types of this, Acute Myeloid/Lymphatic and Chronic Myeloid/Lymphatic, what makes them different?
- Leukemia
(1) Acute myeloid or lymphatic:
• No evidence of maturation in blood or marrow.
• >20% Blast (immature) cells. If higher percent then acute leukemia.
• Can have skin and gum infiltration
(2) Chronic myeloid or lymphatic:
• Increased % of Mature cells referred to as chronic leukemias.
What are solid tumors of the hematopoietic system and Neoplasms (abnormal growth) of lymphoid origin? What do these typically cause? There are two forms of this, what are they and what makes them different? **(Both are clonal expansions at various developmental stages, Lymphomas usually have enlarged, painless lymphadenopathy)
- Lymphomas
- Lymphadenopathy
• Non-Hodgkin Lymphoma: 2 types: Indolent [not likely curable] and very aggressive [more treatable]: survival is years to weeks depending on type and represent 90% of lymphomas.
• Hodgkin Lymphoma: Curable in most cases and represent 10% of lymphomas.
What is Normal hypertension, Prehypertension, Mild, Moderate and Severe?
Normal: <120/80 Prehypertension: 120-139/80-89 Mild: 140-159/90-99 Moderate: 160 or >/100 or > Severe: >180/>110
In individuals with hypertension, what should be the limit of epinephrine? What drug should be avoided? What should be used?
- 0.04 mg/apt of Epinephrine
- Avoid use of Marcaine 0.5% (Bupivicaine)
- Consider using Carbocaine 3% plain (Mepivicaine)
