Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Hematology Module > Platelets > Flashcards

Platelets Flashcards

1
Q

During platelet plug formation, what proteins trigger aggregation?

A

GPIIb-IIIa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What binds to vWF?

A

GPIb-IX-V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where is vWF?

A

Endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Order the intrinsic pathway

A

12–>11–>9 (+8) –> 10 (5) then common pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Order the common pathway

A

10 (+5) –> II (thrombin) –> I (fibrin) –> 13

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Active Protein C inhibits

A

Factor 8 and 5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Not a necessary part of pathway

A

factor 12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

measures intrinsic pathway

A

PTT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

measures extrinsic pathway

A

PT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Thrombin activates

A

5, 7, 8, 11, 13 (almost all odds in a row except 8)

  • *platelet aggregation
  • **activates protein C pathway
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does protein C get activated?

A
  1. Thrombin (II) binds to thrombomodulin
  2. That complex binds to protein C
  3. Protein S then activates it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Heparin MOA

A

activates antithrombin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

____ + _____ form mesh clot

A

fibrin (1) + factor 13

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

______ breaks up mesh clot once activated by ______

A

plasmin,

tPA and plasminogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Antithrombin inhibits

A

Factor 10 and 2 (thrombin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why do we use PT to for warfarin monitoring when it inhibits factors in both pathways?

A

Factor 7, in the extrinsic pathway, had a short half life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

3 roles of fibrin

A
  1. stabilize platelet plug
  2. induces platelet aggregation
  3. starts fibrinolysis process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Vitamin K dependent factors, warfarin inhibits

A

10 9 7 2 (year 1972)

CS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Dense granules contain

A

serotonin, ADP, Ca, ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Alpha granules contain

A

platelet growth factor, trans-growth factor beta, fibrinogen, vWF, platelet factor 4, factor V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Von-Willebrand Factor

A

large protein stored in endothelial cells/platelets
Functions:
1. bind to endothelium, promote platelet adhesion at injury site
2. plasma carrier for factor 8, prevents its degradation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Glycoprotein IIb/IIIa

A

fibrinogen receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

GlycoproteinIb-IX

A

VWF receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Glycoprotein Ia/IIa

Glycoprotein VI

A

collagen receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Endothelial cells: Anticoagulant properties

A
  1. thrombomodulin binds thrombin, activates protein C
  2. Protein S
  3. tissue factor pathway inhibitors
  4. tissue plasminogen activator
  5. prostacyclin/nitric oxide inhibit aggregation
  6. Heparin activates antithrombin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Endothelial cells: Procoagulant properties

A
  1. injury
  2. down regulated thrombomodulin
  3. tissue factor expression
  4. PAI-1 expression
  5. vWF
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

PTT

A

Ref: 25-35 s
Intrinsic Pathway
*UFH monitoring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Reasons for prolonged PTT?

A
  1. Factor VIII or IX deficiency
    aka hemophilia A/B
  2. On heparin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

PT

A

Ref: 10-14 s
Extrinsic Pathway
*warfarin monitoring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Reasons for prolonged PT?

A
  1. on warfarin
  2. vitamin K deficiency
  3. Amyloidosis: factor X bound up
  4. Homocystinuria: VII deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Reasons for Vitamin K deficiency

A

drugs, newbown, low leafys, malabsorption, pancreatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Thrombin time

A

Ref: 14-16 s
good if on direct thrombin inhibitor
measures fibrinogen–>fibrin time

33
Q

Vitamin K antagonist

A

warfarin

34
Q

Factor Xa inhibitors

A

Rivaroxaban (Xarelto)
Apixaban (Eliquis)
Endoxaban (Savaysa)

35
Q

LMWH

A

Enoxaparin (Lovenox)
Dalteparin (Fragmin)
Tinzaparin (Innohep)

36
Q

Bernard-Soulier Syndrome

A

autosomal recessive
defect/loss platelet ADHESION receptors
thrombocytopenia
LARGE PLATELETS

37
Q

Glanzmann Thrombasthenia

A

autosomal recessive

defect/loss receptors LINKING platelets

38
Q

Storage Pool Defects

A

Lack DENSE granules, can’t package

Hermansky, Wiskott, Chediak Diseases

39
Q

Aspirin-like defects

A

COX deficient, thromboxane synthetase deficient

40
Q

Released and activates other platelets

Also inhibitied when taking ASA/NSAIDS

A

thromboxane

41
Q

Gray Platelet Syndrome

A

abnormal ALPHA granule formation/secretion

smear is colorless w/o granules

42
Q

Irreversible drugs

A

aspirin

clopidogrel

43
Q

reversible drugs

A

NSAIDS 12-24 hours

44
Q

Thrombocytopenia presentation

A

low platelets
mucous membranes bleed (epistaxis, gums, GI)
cerebral hemorrage
petechial rash

45
Q

Destructive thrombocytopenia

A

-Ab mediated (ITP)
-Drug related (Heparin)
Splenomegaly/Hypersplenism (trapped)

46
Q

Consumptive thrombocytopenia

A
  • massive trauma
  • dilutional (during transfusion of fluids)
  • complicated surgery
  • consume to stop bleeds
47
Q

ITP

A

autoantibodies against antigen on platelet surface, eventual splenic destruction

48
Q

ITP treatment

A

prednisone 3-6 months, IVIG if severe, then splenectomy if chronic

49
Q

Drug related destruction

A

increased clearance and platelet destruction
Ab forms against drug and it cross reacts with platelets
-Antibiotics
-Heparin

50
Q

HIT

A

hepatin + PF4 forms neoantigen on platelet surface
antibodies attack it
leads to hypercoaguability and clotting

51
Q

Cases of hypoproliferation

A 
BM fails to produce mature platelets
1. leukemia/lymphoma
2. metastatic CA
3. severe viral infection
4. radiation/chemo
could get stem cell transplant
52
Q

Causes of arterial thrombosis

A

platelet plug problem

  1. MI
  2. stroke
  3. peripheral artery vasculitis
  4. antiphos ab syndrome
  5. HIT
  6. hyperhomocyteinemia
53
Q

Factor V Leiden

A

hypercoag-inherited
Factor V is resistant to active protein C
strong association with estrogen, stop OCPs
un-coagulate in pregnancy

54
Q

Prothrombin gene mutation G20210A

A

hypercoag-inherited
upregulate prothrombin expression
cerebral vein thrombosis or stroke

55
Q

Protein C deficiency

A

hypercoag-inherited
decreased synthesis and activitiy
warfarin skin necrosis

56
Q

Protein S deficiency

A

hypercoag-inherited
decreased synthesis and activitiy
warfarin skin necrosis

57
Q

HIT

A

Acquired thrombophilia
heparin induced clot- Ab mediated
switch to direct thrombin inhibitor in future

58
Q

Antiphospholipid syndrome

A 
Acquired thrombophilia
Need one: recurrent miscarraige, VTE, MI, microvascular thrombosis w/ multi organ failure
Need two 12 week apart:
1. Lupus anticoag
2. anticardilipid Ab
2. B2 glycoprotein Ab
59
Q

Antithrombin deficiency

A

hypercoag-inherited

heparin resistance, low antithrombin

60
Q

VTE Risk factors

A 
immobilization
personal/family history
unexplained miscarriages
cigarettes
OCPs
cancer
recent surgery
central venous catheter
trauma
heparin exposure
61
Q

Fibrinolysis

A

conversion of plasminogen to plasmin mediated by tissue plasminogen activator (tpa)

62
Q

Virchow’s Triad

A

Endothelial injury
venous stasis
hypercoagability
(perfect situation for a clot!)

63
Q

DVT long term complication

A

post thrombotic syndrome: perm venous valve damage and long term swelling

64
Q

PE long term complications

A

thromboembolic pulmonary HTN

greater risk of death than DVT

65
Q

DVT symptoms

A

Homan’s sign
pain, swelling, tender
palpable cord
prominent superficial veins

66
Q

PE symptoms

A

SOB, tachycardia, pleuritic chest pain, cough, hemopytsis, hypotension, syncope, death, R side heart failure

67
Q

VTE treatment steps

A
  1. anticoagulate acutely (UFH/LMWH/DOAC)
  2. risk-stratify for thrombolysis (tPA)
  3. convert to chronic anticoagulants (warfarin/DOAC)
68
Q

Bridging to warfarin

A

d/t hypercoaguable state at start, overlap with UFH/LMWH until PT/INR is therapeutic

69
Q

Contraindications for warfarin

A

IVC filter

70
Q

Diagnosing PE

A

VQ Scan: ventilation normal, perfusion altered

PECT w/ contract

71
Q

Treatment for mild hemophilia

A

DDAVP
Prior to surgeries
Releases factor 8 stores
Hemophilia A only

72
Q

Inherited causes of prolonged PTT

A

VWF

Factor VIII, IX, XI, XIII deficiencies

73
Q

Acquired causes of prolonged PTT

A

Heparin

Antiphospholipid antibody

74
Q

Inherited causes of prolonged PT

A

Factor VII deficiency

75
Q

Acquired causes of prolonged PT

A

Vit K deficiency
Liver disease
Warfarin
Factor VIII inhibitor

76
Q

Inherited causes for prolonged PT and PTT

A

Prothrombin, fibrinogen, factor V, factor X, or combined factor deficiencies

77
Q

Acquired causes of prolonged PT and PTT

A 
Vitamin K deficiency
Liver disease
DIC****
Supratherapeutic heparin or warfarin
Combined heparin or warfarin use
Direct thrombin inhibitors
Inhibitor of prothrombin, fibrinogen, or factored V or X
78
Q

Oozing at venapuncture site could indicate

A

K deficiency

79
Q

How does liver disease cause coagulopathy?

A

It has decreased production of clotting factors

(Factor 8 and vWF are not made in liver)*

Hematology Module (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions