BL - Hemostasis Defects Flashcards Preview

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Flashcards in BL - Hemostasis Defects Deck (55):
1

aPTT, Protime (INR), Thrombin time platelet count are all?

Common Screening tests

2

Activated Partial Thromboplastin Time (aPTT) pathway

Citrated Plasma
-->

**Kaolin (surface activator)
phospholipid

--> incubated
--> recalcified
Measure time to clot

3

aPTT Measures the activity of the entire pathway except _________

Factor VII

4

Test Useful to detect Factor VIII, IX, XI, XII deficiencies

Activated Partial Thromboplastin Time (aPTT)

5

Prothrombin Time (protime, PT) pathway

Citrated Plasma
-->

**Thromboplastin
(Tissue Factor)

--> incubated
--> recalcified
Measure time to clot

6

Excess thrombin is added to plasma

Detects low or abnormal fibrinogen, fibrin split products or heparin

Fibrinogen activity should also be measured

Thrombin Time

7

Protime/International Normalized Ratio (PT/INR)

Thromboplastin varies by manufacturer and the time in seconds is “normalized” by adjusting for known potency

8

PT/INR Prolonged with II, VII, V, X and ____ deficiencies

fibrinogen

9

PT/INR Prolonged with vitamin K deficiency and________

liver disease

10

_______ measures platelet function, vessel wall and skin integrity

Bleeding Time/PFA

11

Common Congenital Disorders of Coagulation

Hemophilia A – Factor VIII (Classical)

Hemophilia B – Factor IX (Christmas Disease)

Hemophilia C – Factor XI

Von Willebrand Disease

12

genetic deficiency in clotting factor VIII, which causes increased bleeding and usually affects males.

Hemophilia A – Factor VIII (Classical)

13

a blood clotting disorder caused by a mutation of the factor IX gene, leading to a deficiency of factor IX. It is the second-most common form of haemophilia

Hemophilia B – Factor IX (Christmas Disease)

14

arises from a qualitative or quantitative deficiency of von Willebrand factor (vWF), a multimeric protein that is required for platelet adhesion.

Von Willebrand Disease

15

Unusual Congenital Disorders of Coagulation

Less Common
-Factor VII
-Hypo or dysfibrinogenemia

Rare
-Factor XIII, V, X, and II

16

Differential Diagnosis of Long PTT- non bleeder

Non bleeders:

Factor XII deficiency
Lupus anticoagulant (thrombophilic!)

17

Differential Diagnosis of Long PTT- Bleeder

-Hemophilia A or B
-Factor 11 deficiency
-Acquired Hemophilia Factor 8 autoimmune
-Severe von Willebrand Disease
**Heparin in sample
-Fibrin split products

18

Long PTT means

It took "too long" for blood clotting

19

Hemophilia A or B can only be tested with

Elevated PTT is ONLY abnormal screening te

20

Hemophilia Bleeding Complications

Soft tissue hematoma

Joint bleeding

CNS bleeds – cause of death

Retroperitoneal or psoas bleeds

Post surgical or traumatic bleeds

21

Ecchymoses

a subcutaneous purpura (extravasation of blood) larger than 1 centimeter or a hematoma, commonly called a bruise

22

________cause muscle damage, calcified pseudotumors and atrophy

Hematomas

23

Hemophilia Treatment

Recombinant synthetic factor treatment is effective and given 2-3 times per week IV to prevent disability.

24

Causes of a Prolonged PT ± PTT

Liver disease

Vitamin k deficiency

Warfarin or rat poison ingestion

25

Decreased vitamin k dependent carboxylation of II, VII, IX and X can be a result of

Abnormalities in Liver Disease

26

Factor 11 deficiency

Hemophilia C

27

Post prostate surgery with bleeding can be

Hemophilia C

28

Decreased fibrinogen production and increased fibrinolysis can be a result of

Abnormalities in Liver Disease

29

The ______measures the procoagulant
activity of the factors VII, X, V, II and fibrinogen. This is the extrinsic pathway

protime (PT)

30

measures the procoagulant activity of
fibrinogen and is also very sensitive to the anticoagulant effect of heparin or fibrin split
products.

Thrombin Time (TT)

31

measures the platelet and vessel interaction, as well as the number and the function of platelets.

Bleeding Time (BT)

32

A new device, the _________, can perform an in vitro bleeding time. It also can determine platelet response to agonists.

Platelet Function Analyzer

33

Less than 1% factor activity – Severe _____

Hemophilia

34

2% to 5% factor activity- _______ Hemophilia

Moderate

35

In Factor VII deficiency only the protime (PT) is prolonged. The______is normal.

PTT

36

hepatic function can cause deficiencies of the clotting factors. This is especially true for Factor V and for the ______dependent Factors, II, VII, IX, and X.

vitamin K

37

> 10% factor activity- _______- Hemophilia

Mild

diagnosed after a bad traumatic event or after a bad result from surgery.

38

Vitamin K deficiency and _____ administration which interfere with the vitamin K utilization, are very common causes of a prolonged protime with normal or slightly prolonged PTT.

warfarin

39

Long acting fat soluble rat poisons are used in suicide attempts.

These patients present with _____ labs and require very intensive vitamin K therapy for months

extremely prolonged protime and PTT

40

Massive trauma, hemorrhagic or septic shock, amniotic fluid embolism, burns, acute leukemia or transfusion and drug reactions can all cause _________

disseminated intravascular coagulation

41

________is the formation and propagation of clot within the vasculature; this term refers to an abnormal or pathologic process with imbalance in the hemostatic system.

Thrombosis

42

a very common acquired abnormality which results in a hypercoaguable state. The anticoagulant is an IgG antibody, which reacts against phospholipid in the platelet membrane or endothelial cell.

The Lupus Anticoagulant

43

Factor V Leiden hypercoagulability results from a mutation in Factor V so that it is not inactivated by______.

protein C

44

deficiencies of antithrombin, protein C and protein S or resistance to protein C (Factor V Leiden) have what in common

The four most common familial
congenital conditions which cause a hypercoagulable syndrome

45

DIC mantra

treat the underlying disorder

Replace platelets and fibrinogen

Rarely: stop progression with anticoagulation

46

_____________hypercoagulability results from a mutation in Factor V so that it is not inactivated by protein C.

Factor V Leiden

47

Hypercoagulable States

Impairment of blood flow

Congenital deficiencies of endogenous anticoagulants

Cancer

Thrombocytosis – high platelets (P vera)

Antiphospholipid Syndrome – Lupus Anticoagulant

48

in vitro prolonged PTT but causes in vivo thrombotic disorders

Lupus Anticoagulant

49

Associated with lupus sometimes

Venous and arterial thrombosis

Hepatic vein thrombosis

Recurrent miscarriage

Migraine headaches

may indicate?

Antiphospholipid Syndrome – Lupus Anticoagulant

50

Russell Viper Venom Test (RVVT) or Platelet Neutralization Test with correction are common tests for?

Confirmation of Lupus Anticoagulant

51

Even though the PTT is prolonged in vitro, the patients do not have bleeding. instead they have a thrombotic syndrome which includes deep vein thrombosis, pulmonary embolism, thrombotic strokes and recurrent miscarriage due to thrombotic disease of the _________.

placental blood vessels

52

The most consistent laboratory findings are that the fibrinogen level has decreased markedly and the platelet count is low.

Disseminated Intravascular Coagulation (DIC)

53

Acquired Factor Inhibitors

acquired Factor VIII inhibitor
only laboratory test to be abnormal will be the PTT
excellent long-term prognosis

54

von Willebrand protein has two functions.

adhere platelets to exposed collagen
carry Factor VIII

55

The classic presentation is post-operative hemorrhage since most people do not have spontaneous bleeding.

Factor XI Deficiency