Coagulation And Coagulopathies

Front 1

What three things does hemostasis depend on?

Back 1

1. Activation of clotting cascade
2. Vasoconstriction
3. Formation of platelet plug

Front 2

Intrinsic tissue damage is?

Back 2

contact between blood and exposed endothelial cell surfaces

Front 3

Extrinsic tissue damage is?

Back 3

vascular injury exposing tissue factor (thromboplastin or factor III) - subendothelial cell-surface glycoprotein

Front 4

What is the lifespan of a platelet?

Back 4

8-12 days

Front 5

What is a normal platelet count?

Back 5

150-400K per ml

Front 6

What is the best test for platelet function?

Back 6

bleeding time

Front 7

Adhesion of platelets occurs how?

Back 7

damage to endothelium releases vWF which then anchors itself to the exposed subendothelial collagen

Front 8

Activation of platelets occurs how?

Back 8

platelets have a receptor that attaches itself to the exposed end of vWF attached to the subendothelial collagen AND thrombin attaches to the thrombin receptor on the platelet= change shape and release TxA2 and ADP

Front 9

What promotes platelet aggregation?

Back 9

TxA2 and ADP

Front 10

TxA2 and ADP uncover __________ receptors on the platelet.

Back 10

fibrinogen

Front 11

What interconnects platelets?

Back 11

fibrinogen

Front 12

What is produced that cross links the platelets and forms a platelet plug?

Back 12

fibrin

Front 13

What clotting factors are involved in the intrinsic pathway?

Back 13

8,9,11,12

Front 14

What lab tests assess the intrinsic pathway?

Back 14

PTT and ACT

Front 15

What drug interferes with the intrinsic pathway?

Back 15

heparin

Front 16

What does heparin allow?

Back 16

antithrombin III to more effectively bind IIa and factor Xa thus not allowing the final fibrin cross linking to occur

Front 17

What is required to complete the intrinsic pathway?

Back 17

calcium

Front 18

What clotting factors are involved in the extrinsic pathway?

Back 18

3 & 7

Front 19

Factor 3 is also known as?

Back 19

thromboplastin

Front 20

What is the primary initiator of coagulation?

Back 20

thromboplastin

Front 21

What lab tests assess the extrinsic pathway?

Back 21

PT and INR

Front 22

If a patient is on a continuous heparin infusion and has a low ACT what should you do?

Back 22

give FFP, contains antithrombin III and all clotting factors but not platelets

Front 23

What drug interferes with the extrinsic and final common pathway?

Back 23

coumadin

Front 24

What does coumadin do?

Back 24

binds to vitamin K receptors in the liver causing competitive inhibition of vitamin K

Front 25

What are the dependant clotting factors for vitamin K?

Back 25

2, 7, 9, 10

Front 26

What starts the final common pathway?

Back 26

factor X is activated by completion of intrinsic and extrinsic pathway and complexes on the surface of the platelet with activated factor V and calcium

Front 27

What are the clotting factors in the final common pathway?

Back 27

1, 2, 5, 10, 13

Front 28

What is the sequence of steps in the final common pathway?

Back 28

factor Xa converts prothrombin (II) to thrombin (IIa) which then converts fibrinogen (I) to fibrin (Ia)- cross linking occurs with the addition of factor VIIIa forming a platelet plug

Front 29

What is a normal fibrinogen level?

Back 29

200-400 mg/dl

Front 30

What is the lab test that measures the conversion of fibrinogen to fibrin?

Back 30

thrombin time (TT)

Front 31

What is the most common inherited coagulation defect?

Back 31

von Willebrand's Disease

Front 32

A pt with von Willebrand's has an increased _______ ______.

Back 32

bleeding time

Front 33

What is the treatment for vWF?

Back 33

1. DDAVP
2. Cryo
3. Factor VIII concentrates

Front 34

What factors do cryo contain?

Back 34

VIII, VIII:vWF, I, and XIII

Front 35

What is the second most common inherited disease?

Back 35

Hemophilia A

Front 36

What is Hemophilia A?

Back 36

Factor VIII:C deficiency

Front 37

What is the treatment for Hemophilia A?

Back 37

1. FFP
2. Cryo
3. Factor VIII concentrate

Front 38

Hemophilia B (Christmas Disease) is?

Back 38

a factor IX deficiency

Front 39

What is the treatment for Hemophilia B?

Back 39

1. FFP
2. Factor IX concentrates

Front 40

A patient with Hemophilia B you want to avoid what?

Back 40

IM injections, invasive monitoring, trauma (excessive instrumentation of the airway)

Front 41

What is afibrinogenemia?

Back 41

congenital absence of fibrinogen

Front 42

What lab tests are abnormal for a patient with afibrinogenemia?

Back 42

PT, PTT, TT all prolonged

Front 43

What is the treatment for a patient with afibrinogenemia?

Back 43

1. fibrinogen concentrates
2. cyroprecipitate

Front 44

Normally ATIII binds factors ____ and ____ greatly and ___, ___, ___, to a lesser degree.

Back 44

IIa and Xa
IX, XI, XII

Front 45

What results from a antithrombin III deficiency?

Back 45

hypercoagulable state (increased incidence of thromboembolic disease

Front 46

What is the most common cause of resistance to heparin?

Back 46

antithrombin III deficiency

Front 47

How does antithrombin III deficiency result?

Back 47

DIC, nephritic syndrome, chronic liver disease, prolonged heparin administration, and increased protein catabolism

Front 48

What is treatment for antithrombin III deficiency?

Back 48

chronic-oral anticoagulants
acute- FFP, ATIII concentrates, heparin

Front 49

Vitamin K is necessary for the production of what factors?

Back 49

2, 7, 9, 10

Front 50

what abnormal lab tests are included in a diagnosis for vitamin K deficiency?

Back 50

prolonged PT, and normal PTT

Front 51

What is the treatment for drug induced hemorrhage?

Back 51

protamine- highly positively charged protein that electrostatically binds to highly negatively charged heparin
-dose 1-1.5mg/100U of heparin

Front 52

What is the most common cause of bleeding following massive blood replacement?

Back 52

dilutional thrombocytopenia (platelets become dysfunctional after 1-2 days in stored blood

Front 53

Plavix

Back 53

ADP receptor anatgonist
-irreverisble modification
-max efficiency days 3-7
-40-60% platelet inhibition
-5 days for normal lab resumption

Front 54

DIC is?

Back 54

uncontrolled activation of the coagulation system with consumption of platelets and procoagulants

Front 55

In DIC what is deposited in microcirculation?

Back 55

fibrin

Front 56

In DIC, what would you expect coagulation tests to look like?

Back 56

1. PTT, PT, and TT elevated
2. Fibriongen level normal-decreased
3. Low platelet count
4. Increased Fibrin Degradation Products

Front 57

What is the treatment for DIC?

Back 57

First-correct etiology then increase fibrinogen and platelet levels, possibly heparin or amicar

Front 58

What does ASA do?

Back 58

irreversible acetylates cyclo-oxygenase for life of platelet

Front 59

What converts arachodonic acid to TxA2?

Back 59

cyclo-oxygenase

Front 60

What does ASA ultimately impair?

Back 60

aggregation of platelets

Front 61

What is the treatment for someone who is on ASA needing surgery?

Back 61

pooled platelets

Front 62

What may ASA also do?

Back 62

displace highly protein bound drugs

Front 63

What is idiopathic thrombocytopenic purpura (ITP)

Back 63

decreased platelets due to autoimmune destruction by antiplatelet immunoglobulin (IgG)

Front 64

What is the hallmark signs of ITP?

Back 64

petechiae and mucosal bleeding

Front 65

Who is ITP seen most in?

Back 65

children and young adult females

Front 66

Heparin induced thrombocytopenia?

Back 66

is a immune mediated drug reaction

Front 67

Which type of HIT is less severe and has only a modest decrease in platelets and is reversible?

Back 67

type I

Front 68

HIT type II?

Back 68

severe decrease in platelets, immune related, activates platelets (associated wiht thromboembolism), occurs 4-6 days after administration

Front 69

What is the treatment for ITP? 5

Back 69

1. Corticosteroids
2. IV IgG
3. D/c heparin
4. Splenectomy
5. Platelets

Front 70

What are four precipitating factors for a sickling crisis?

Back 70

1. Hypoxia
2. Hypothermia
3. Acidosis
4. Dehydration

Front 71

Sickle cell anemia is typically found in?

Back 71

African Americans

Front 72

What is the patho of sickle cell anemia?

Back 72

1. Glutamate replaces valine in 6th position of the beta chain of hemoglobin (Hb S) allowing Hb S to predominate over normal Hb A, when exposed to undesirable situations, Hb S aggregates into long stacks called tactoids

Front 73

In sickle cell anemia, there is a decreased _____ and lower ____ ____ ____.

Back 73

Hct (18-30%)
RBC life span (10-15 days compared to 120 days)

Front 74

What may provide some protection against sickling?

Back 74

increased Hb F, prevents tactoid formation
-disappears after first year of life

Front 75

What induces Hb F production?

Back 75

Hydroxyurea

Front 76

Risk factors for sickling?

Back 76

1. Low PaO2- 50 mmHg, pronounced at 20 mm Hg
2. Greater in veins vs. arteries
3. Acidosis- regardless of PaO2
4. Hypothermia
5. Dehydration
6 Local factors- stasis of blood causes hypoxemia which then promotes more sickling

Front 77

What is the diagnosis of sickle cell anemia?

Back 77

hemaglobin electrophoresis - placed with oxygen consuming reagant (metabisulfite) or a hypertonic ionic solution (solubility test)

Front 78

Hb SS

Back 78

sickle cell anemia- homozygous- received gene from both parents

Front 79

Hb AS

Back 79

sickle cell trait - variable amounts of Hb A (55-60%) vs Hb S (35-40%)- heterozygous - received gene from one parent

Front 80

Which variant of sickle cell disease has more complications?

Back 80

Hb SS

Front 81

In Hb SS, what are cardiac manifestations? 4

Back 81

1. LVH
2. Cardiomegaly
3. Increased CO and Diastolic flow murmurs
4. Decreased right ventricular filling

Front 82

In Hb SS, what are renal manifestations? 3

Back 82

1. Renal medulla prone to infarction and necrosis
2. Decreased GFR
3. Nephrotic syndrome- proteinuria, hematuria, inability to concentrate urine

Front 83

In Hb SS, what are hepatic manifestations?

Back 83

1. cholelithiasis- pigmented stones
2. Increased bilirubin due to chronic hemolysis
3. Hepatic infarcts

Front 84

In Hb SS, what are neurologic manifestations?

Back 84

Stroke or intracranial hemorrhage

Front 85

What are musculoskeletal manifestations?

Back 85

1. Vasoocclusive sickling infarcts the artery to the femur causing necrosis of the femoral head- 10% of patients may require THA
2. Excruciating musculoskeletal pain

Front 86

In Hb SS, what are hematologic manifestations?

Back 86

1. Hgb baseline 6-8 g/dL
2. Right shift of the OHDC

Front 87

Describe the infarctive crisis

Back 87

1. Infection or trauma
2. Acute abdominal, chest, back of joint pain
3. Due to micro-infarcts in various tissues

Front 88

Describe the Aplastic crisis

Back 88

1. profound anemia Hgb 2-3 g/dL
2. Due to bone marrow suppression or exhaustion
3. Caused in part by viral infections and folate deficiency

Front 89

Describe Splenic Sequestration Crisis

Back 89

1. Infants and young children
2. Sudden pooling of blood in spleen
3. Hypotension- life threatening
4. Due to partial or complete blockage of venous drainage from the spleen

Front 90

What is the treatment for a sickle cell crisis?

Back 90

1. Hydration prevents hypovolemia
2. Na bicarb to counteract acidosis
3. Pain control
4. Exchange transfusions
5. Hydroxyurea

Front 91

What is a exchange transfusion?

Back 91

Increase total Hb to 10-12 g/dL, decrease Hb S to less than 40% of total
-usually only for surgery of chest, abdomen, or resection of tonsils and/or adenoids

Front 92

In someone with sickel cell disease what should you avoid?

Back 92

preop sedation, TQ, hypotension

Front 93

What may you expect to see with pulse oximetry value?

Back 93

low- decreaesd oxygen carrying ability of Hb S

Front 94

What type of anesthetic is preferred in a patient with sickle cell disease?

Back 94

regional - maintains pulmonary function, decreases blood loss, decreased incidence of thromboembolic events