CS Exam 2 Flashcards
(64 cards)
1
Q
Meds that increase PT
A
warfarin
salicylates (aspirin, pepto bismol)
2
Q
Meds that decrease PT
A
Estrogen/OCPs
Vitamin K
3
Q
Conditions that lead to decreased Vitamin K
A
- bile duct obstruction
- drugs: abx
- diarrhea
- malabsorption syndromes
- dietary deficiency
4
Q
Warfarin/Coumadin MOA
A
- decreases Vitamin K production, thereby inhibiting vitamin K dependent factors
- affects PT
5
Q
Meds that increase PTT
A
*Heparin
Antihistamines
Ascorbic acid
Salicylates
6
Q
Heparin MOA
A
- activates factor II (Antithrombin)
- effect = immediate and short-lived
- affects PTT
- can cause drug-induced thrombocytopenia
7
Q
Normal platelet count
A
150,000-450,000
8
Q
Vitamin K-dependent clotting factors
A
II, VII, IX, X
also Protein C & S
9
Q
Factor IV (Calcium) MOA
A
- required for coagulation factors to bind to phospholipids
- necessary for activation of many factors
10
Q
Factor V Leiden MOA
A
- clotting disorder
- inherited mutation in which protein C cannot inhibit Factor V
11
Q
Factor VIII: what are the 2 components?
A
- Antihemophilic factor (factor VIII)
- VWF (inactivates/stabilizes VIII) (also promotes platelet adhesion to collagen)
12
Q
Where is Factor III found?
A
- Tissue factor
- membrane protein on cells surrounding BV
- exposed when vessels ruptured
13
Q
Factor V MOA
A
helps Factor Xa convert prothrombin to thrombin
14
Q
Where is Factor VIII produced?
A
- liver, but also
- endothelial cells
- RES
- megakaryocytes
- therefore: #s not decreased in severe liver dysfunction
15
Q
Factor XIII: MOA
A
- Fibrin Stabilizing Factor
- stabilizes clot
- activated by thrombin
- binds to fibrin, crosslinks fibrin units
16
Q
Explain the thrombin time lab test
A
- asses fibrinogen deficiency
- excess thrombin added to sample to assess whether fibrinogen>fibrin step is rate limiting
- non-improvement= qualitative or quantitative fibrinogen issue
17
Q
Thrombocytopenia: platelet count
A
<150,000
18
Q
DIC: Lab values
A
- prolonged PT and PTT*
- decreased fibrinogen
- increased D-dimer
19
Q
ITP: labs
A
- large platelets
- antibodies to platelets
20
Q
Aspirin: MOA
A
- irreversibly blocks arachidonic acid, affecting platelets aggregation
- d/c: 7-10 days until platelet restoration
21
Q
NSAIDS: MOA
A
- reversibly inhibit COX
- d/c: 24-48 hours until platelet restoration
22
Q
Von Willebrand Dz: MOA
A
- inherited deficiency, now antihemophilic factor is not kept stabilized by VWF
- affects ligands that adhere platelets to endothelium
23
Q
Mild-moderate liver dz: PT and PTT expected labs
A
PT prolonged, PTT normal
24
Q
Severe liver disease: PT and PTT expected labs
A
both prolonged
25
What does Protein C do?
- combines with Thrombomodulin
- complex activated by Protein S
- inactivates factors Va and VIIIa
- outcome: decreased thrombin production
26
aPL syndrome: MOA
- antiphospholipid antibody
- autoimmune attack of Apolipoprotein H
- Apo-H normally inhibits platelet agglutination, therefore aPL syndrome leads to clotting
27
Labs to test for antiphospholipid antibody
- anticardiolipin ab’s (IgM and IgG)
- Anti-B2 glycoprotein I ab’s (IgM and IgG)
- Lupus anticoagulant (specific lupus-associated ab)
28
Homocysteine levels: interfering factors
* renal impairment (decreased filtration)
* lack of dietary B vitamins
* smoking (increases)
- levels increase w/ age
- men > women
29
Antithrombin: MOA
- endogenous inhibitor of Factor X and Thrombin
| - activated by heparin
30
Arterial thrombotic workup: indications
- arterial thrombosis prior to age 55 w/o other risk factors
| - 2 months after episode (acute phase reactants may alter results)
31
Arterial thrombotic workup labs
- tPA antigen
- C-reactive protein
- Lupus Anticoagulant panel (lupus inhibitor, antiphospholipid)
- Plasma homocysteine
32
Venous thrombotic workup: timing
- 2 months after episode (acute phase reactants may alter results)
- allow for completion of anticoagulation therapy (off for 7-10 days prior to testing)
33
Venous thrombotic workup labs
- APC resistance test
- Protein C activity
- Protein S free antigen
- Antithrombin activity
- Lupus inhibitor assay
- If all negative... prothrombin DNA screen, Factor VII, Factor VIII, CRP
- if APCR + , check Factor V DNA screen
34
Microcytic anemia
- Fe def
- AI/CD (normo or micro)
- Thalassemia
- Sideroblastic
- Copper deficiency/zinc poisoning
35
Reasons for falsely elevated retic counts
pregnancy
| Howell-Jolly bodies
36
How do you tell if RPI is adequate?
< 2 = inadequate
| > 3 = definitely adequate
37
Basophilic stippling: associated conditions
```
visible ribosomes
visible when Wright stained
-lead poisoning
-other heavy metal poisoning
-alcohol
-reticulocytosis
```
38
Howell-Jolly bodies
leftover DNA fragments
| -underperforming/nonfunctional/missing spleen
39
Tear drop cells: associated conditions
myelofibrosis
| thalassemia
40
Burr cells
* commonly an artifact of EDTA use
| - seen in uremia, liver disease, severe burns
41
Iron-deficiency anemia: transferrin saturation value
<15%
42
Most sensitive test to determine Fe def anemia
serum ferritin
43
Which drugs increase transferrin/TIBC?
fluorides
| OCPS
44
Which drugs decrease transferrin/TIBC?
ACTH
| chloramphenicol
45
Sideroblastic anemia: iron panel lab results
- normal or high across the board
| - bone marrow bx
46
If Hbg >9 and normal RDW with known chronic disease, we presume which dz?
AI/CD
47
What ANC value is considered severe immuncompromisation and warrants protective isolation?
<100
48
Values:
- critical leukocytosis
- leukocytosis
- leukopenia
- critical leukopenia
>30,000
>10,000
<4,000
<2,500
49
Clinical manifestations of critically LOW Hgb levels
- angina
- MI
- CHF
- CVA
50
Clinical manifestations of critically HIGH Hgb levels
- CVA
| - organ failure
51
Drugs that increase RBC and Hgb
EPO
| anabolic steroids
52
When do we transfuse pt?
Hgb < 6 almost always appropriate
Hgb <7-8 maybe, depends
Hgb <10 almost never appropriate
53
Neutrophils: production time and lifespan
produced in 7-14 days
| in circulation of 6 hours
54
Basophils: function
- allergic rxn and parasitic infx
- phagocytosis of antigen-antibody complexes
- do NOT respond to bacterial/viral infx
- heighten inflammatory response (heparin, histamine, peroxidase)
55
Eosinophils: function
- allergic rxn and parasitic infx
- phagocytosis of antigen-antibody complexes
- do NOT respond to bacterial/viral infx
56
Monocytes (macrophages): function
- phagocytic cells similar to neutrophils
- produced more quickly and circulate longer in blood stream than neutrophils
- produce interferon* (immunostimulant)
57
Monocytosis: conditions
- chronic inflammatory disorders
- viral infx
- parasites
58
Basopenia: conditions
acute allergic rxns
59
Neutropenia: conditions
aplastic anemia
60
platelets: lifespan
7-9 days
61
Antiplatelet agents: examples
aspirin
| clopidogrel
62
What factors does thrombin induce?
1, 5, 8, 11, 13, thrombomodulin
63
Conditions which exhibit acquired Factor VIII deficiency
pregnancy
autoimmune disorders
malignancies
64
Define: warfarin necrosis
- tissue necrosis occurs because of a deficiency in Protein C
- occurs b/c inhibition of Protein C is initially stronger than inhibition of other Vitamin K dependent coag factors
