Hematology

Question 1

What is the most common congenital bleeding disorder?

Answer 1

von Willebrand’s disease

Question 2

What are the three types of vWD?

Answer 2

• I: reduced quantity of vWF
• II: dysfunctional vWF
• III: absent vWF

Question 3

How are the three types of vWD treated?

Answer 3

• I: desmopressin or cryo
• II: desmopressin or cryo
• III: cryo or FVIII (desmopressin doesn’t work)

Question 4

Cryo is helpful in treating which bleeding disorders?

Answer 4

vWD, hemophilia A, hypofibrinogenemia

Question 5

What factors are missing in hemophilia A and B?

Answer 5

• A: missing factor VIII (treat with cryo or recombinant
  FVIII)
• B: missing factor IX (treat with FFP or recombinant FIX)

Question 6

Which products are used to treat hemophilia A and B?

Answer 6

• A: cryo or recombinant FVIII
• B: FFP or recombinant FIX

Question 7

PTT measures which coagulation pathway?

Answer 7

the intrinsic

Question 8

What raises suspicion for HITT? How is it tested for?

Answer 8

• concern is with thrombosis, thrombocytopenia, and expected timing
• anti-PF4 is for initial screening and serotonin release assay is confirmatory

Question 9

What is the pathophysiology of warfarin induced skin necrosis?

Answer 9

the short half-life of protein C and S (natural anticoagulants) leads to a brief period of time where patient is hypercoagulable

Question 10

How does heparin work?

Answer 10

it potentiates the effects of antithrombin III

Question 11

What drug is used to reverse heparin?

Answer 11

protamine

Question 12

What are the side effects of protamine?

Answer 12

hypotension and bradycardia

Question 13

What are the characteristics of anti phospholipid syndrome? How do you diagnose and treat it?

Answer 13

• history usually includes symptoms of lupus, prior DVTs, and/or recurrent pregnancy loss
• have a prolonged PTT but are hypercoagulable
• look for cardiolipin or lupus anticoagulant antibodies
• treat with heparin bridge to coumadin

Question 14

Prolonged PTT but hypercoagulable is suggestive of what diagnosis?

Answer 14

anti-phospholipid syndrome

Question 15

How does warfarin work?

Answer 15

by inhibiting VKORC, a protein that reduces vitamin K to activate it, inhibiting synthesis of factors X, IX, VII, II and protein C/S

Question 16

Which anti-coagulant is contraindicated during pregnancy?

Answer 16

warfarin

Question 17

Recurrent pregnancy loss is suggestive of what hematologic disorder?

Answer 17

anti-phospholipid syndrome

Question 18

How can the effectiveness of lovenox checked?

Answer 18

by looking at FXa levels

Question 19

What is andexanet alfa?

Answer 19

a decoy receptor for FXa inhibitors like eliquis and rivaroxaban (the newer reversal agent)

Question 20

What is the mechanism of action of tPA?

Answer 20

it activates plasminogen to break down fibrinogen

Question 21

How is tPA reversed?

Answer 21

with aminocaproic acid

Question 22

What are the contraindications to using tPA?

Answer 22

• absolute: active internal bleeding, recent CVA or neurosurgery, recent GI bleed
• relative: surgery in last 10 days, recent organ biopsy, recent delivery, recent major trauma, uncontrolled hypertension

Question 23

Which coagulation factors are not synthesized in the liver?

Answer 23

FVIII and desmopressin

Question 24

What is the role of thrombin (FII)?

Answer 24

convert fibrinogen to fibrin and activate platelets

Question 25

What is the role of fibrin?

Answer 25

link platelets to at the GPIIB/IIIA receptor to form a platelet plug

Question 26

What is the action of antithrombin III?

Answer 26

binds and inhibits thrombin

Question 27

What does cryo contain?

Answer 27

FVIII, fibrinogen, and vWF