Bleeding Disorder Drug

Question 1

In secondary coagulation the extrinsic pathway is started when damaged endothelial cells release factor III (tissue factor III) which binds with the active factor VIIa (7a) and Ca2+. This then forms the VIIa-TF complex on the smooth muscle of blood vessels. The VIIa-TF complex then cleaves what factor?

1 - factor II (2 or prothrombin)
2 - factor X forming Xa
3 - factor VIII (8)
4 - factor V (5)

Answer 1

2 - factor X forming Xa

Question 2

Once factor Xa has become active due to the extrinsic pathway, what factor does Xa (10a) and Ca2+ bind with that will then go onto form the prothrombinase complex?

1 - factor II (2 or prothrombin)
2 - factor I (1)
3 - factor VIII (8)
4 - factor V (5)

Answer 2

4 - factor V (5)

Question 3

Once the prothrombinase complex has been formed by active factors X (10) and V (5), what does this then cleave in the extrinsic pathway?

1 - factor II (2 or prothrombin)
2 - factor I (1)
3 - factor VIII (8)
4 - factor XII (12)

Answer 3

1 - factor II (2 or prothrombin)
- prothrombin becomes thrombin (IIa)

Question 4

Which pathway of the coagulation cascade doe the prothrombin time (PT), which is essentially the time it takes to form a clot measures?

1 - common
2 - extrinsic
3 - intrinsic

Answer 4

2 - extrinsic pathway

• essentially this is the time it takes to form a clot
• tissue factor (III), Ca2+ and factor VII (7) form complex and active factor X (10)
• factor X (10) binds factor V (5) and Ca2+ and cleaves prothrombin into thrombin, which is where the name prothrombin time comes from

Question 5

What is the normal value for prothrombin time (PT), which is essentially the time it takes to form a clot?

1 - 0.1 - 1.4 secs
2 - 1-4 secs
3 - 10-14 secs
4 - 15-20 secs

Answer 5

3 - 10-14 secs

Question 6

In the coagulation cascade, activated partial thromboplastin time (aPTT) is a measure of which aspect of the coagulation cascade?

1 - common
2 - extrinsic
3 - intrinsic

Answer 6

3 - intrinsic

• time it takes the intrinsic and common pathway to form a clot following the addition of calcium and phospholipid emulsion in-vitro

Question 7

In the coagulation cascade, activated partial thromboplastin time (aPTT) is a measure of the intrinsic and common pathway to form a clot following the addition of calcium and phospholipid emulsion. What is the normal time for this?

1 - 0.1 - 1.4 secs
2 - 1-4 secs
3 - 10-14 secs
4 - 27-41 secs

Answer 7

4 - 27-41 secs

Question 8

What is the international normalised ratio (INR)?

1 - measure of aPTT compared to age and gender matched aPTT
2 - measure of AP
3 - measure of PT as a ratio to a standardised or control PT

Answer 8

3 - measure of PT as a ratio to a standardised or control PT

• PT is a measure of how long it takes clot to form
• measures extrinsic pathway

Question 9

The international normalised ratio (INR) is a measure of PT as a ratio to a standardised or control PT. What is a normal value for INR?

1 - 0.1 - 1.4
2 - 1-1.3
3 - 10-14
4 - 27-41

Answer 9

2 - 1-1.3

Question 10

What is the purpose of the coagulation cascade?

1 - accentuate primary haemostasis
2 - convert fibrinogen into fibrin
3 - inhibit platelets activation in primary haemostasis

Answer 10

2 - convert fibrinogen into fibrin

• fibrinogen = factor 1
• fibrin = 1a
• fibrin are monomers that form crosslinks and a strong clot

Question 11

The coagulation cascade has 3 parts, intrinsic, extrinsic and common pathways. How is the intrinsic pathway started?

1 - factor XII (12) comes into contacts with collagen or activated platelets
2 - factor X (10) binds with fibrin
3 - factor XII (12) binds von willebrand factor
4 - factor XII (12) binds inactive platelets

Answer 11

1 - factor XII (12) comes into contacts with collagen or activated platelets

• platelets are activated from primary haemostasis

Question 12

Once the intrinsic pathway has begun by factor XII (12) binding with activated platelets or collagen, what then happens in the intrinsic pathway?

1 - factor XII (12) then becomes factor X (10)
2 - activated platelets activate factor XI
3 - factor XII (12) becomes factor XIIa (12a) and activates factor XI (11), then IX (9) and then X (10)
4 - collagen activates factor XI (11)

Answer 12

3 - factor XII (12) becomes factor XIIa (12a) and activates factor XI (11), then IX (9) and then X (10)

Question 13

In the intrinsic pathway, which factor activates the common pathway?

1 - factor XIIa (12a)
2 - factor XIa (11a)
3 - factor IX (9)
4 - factor Xa (10a)

Answer 13

4 - factor Xa (10a)

• Xa (10a) then activates factor II (2) called thrombin
• factor II (2) called thrombin then activates factor I (1) which builds the fibrin mesh

Question 14

Once the common pathway has been activates by factor Xa (10) it activates factor II (2 thrombin) which activates factor Ia (1a, called fibrin) which begins building fibrin. Which 4 other cofactors is factor IIa (2a thrombin) able to also activate?

1 - Ia (1a), IIIa (3a), IVa (4a) and V (5a)
2 - XIa (11a), IIIa (3a), IVa (4a) and VIIa (7a)
3 - IIIa (3a), IVa (4a), Va (5a) and XIIa (12a)
4 - Va (5a), VIIIa (8a), IXa (9a) and XIIIa (13a)

Answer 14

4 - Va (5a), VIIIa (8a), IXa (9a) and XIIIa (13a)

• Va (5a) acts as a cofactor for factor Xa (10a)
• VIIIa (8a) acts as a cofactor for factor IXa (9a)
• IXa (9a)
• XIIIa (13a) helps factor I (1a) called fibrin form crosslinks and a stronger clot

Question 15

The extrinsic pathway is activated when factor VIIa (7a) binds with what on exposed tissue?

1 - von Willebrand factor
2 - tissue factor
3 - tissue plasminogen factor
4 - protein C

Answer 15

2 - tissue factor

• factor VIIa (7a) then activates the factor Xa (10a) and the common pathway

Question 16

In secondary haemostasis, which factor is often referred to as the accelerator due to its multiple procoagulating functions?

1 - factor IIa (2a)
2 - factor Xa (10a)
3 - factor Va (5a)
4 - factor Ia (1a)

Answer 16

1 - factor IIa (2a)
- also referred to as thrombin

Question 17

Thrombin (factor IIa (2a) is able to do lots of things involved in coagulation. It does all of the following EXCEpt which one?

1 - binds platelets activating them
2 - activates factor Va (5a)
3 - activates factor VIIIa (8a)
4 - converts fibrinogen (factor I (1) into fibrin (factor Ia (1a))
5 -converts factor XIII (13) into factor XIIIa (13a) that binds with Ca2+ cofactor forming cross bridges between fibrin mesh
6 - activates protein C and S

Answer 17

6 - activates protein C and S

• proteins S and C ensure clotting does not go into overdrive

Question 18

Factor IIa (2a) also called thrombin is one of the key cofactors in secondary haemostasis. What is the bodies natural molecule that aims to modulate the activation of thrombin?

1 - protein S
2 - protein C
3 - antithrombin (factor IIIa (3a))
4 - factor Va (5a)

Answer 18

3 - antithrombin (factor IIIa (3a))

Question 19

Factor IIa (2a) also called thrombin is one of the key cofactors in secondary haemostasis. Antithrombin (factor IIIa (3a)) is the bodies naturally produced modulator of thrombin. Which 2 key factors in the common pathway is antithrombin (factor IIIa (3a)) able to bind with and reduce coagulation?

1 - factors Va (5a) and Xa (10a)
2 - factors IIa (2a) and Xa (10a)
3 - factors XIIIa (8a) and Xa (10a)
4 - factors IIa (2a) and XIIIa (13a)

Answer 19

2 - factors IIa (2a) and Xa (10a)

• this essentially inhibits or reduces the activity of the common pathway
• factor Xa converts prothrombin into thrombin (factor IIa (2a))
• remember 2 + 7 = 9, 10, 11, 12

Question 20

Which factors overall is anti-thrombin (IIIa (3a)) able to bind with and inhibit?

1 - factors 1, 2, 3, 4 and 5
2 - factors 2, 7, 9, 10, 11 and 12
3 - factors 1, 2, 7, 9 and 10
4 - factors 5, 7, 9, 11, 13

Answer 20

2 - factors 2, 7, 9, 10, 11 and 12

• remember 2 + 7 = 9, 10, 11, 12

Question 21

Which factors in the coagulation cascade synthesised in the liver are vitamin K dependent?

1 - 2, 3, 4 and 5
2 - 2, 7, 9 and 10
3 - 2, 4, 6 and 8
4 - 2, 7, 10 and 12

Answer 21

2 - 2, 7, 9 and 10

• all factors are enzymes
• these enzymes require vitamin K to be effective

Question 22

Which factors of the coagulation cascade is Warfarin able to inhibit?

1 - 2, 3, 4 and 5
2 - 2, 7, 9 and 10
3 - 2, 4, 6 and 8
4 - 2, 7, 10 and 12

Answer 22

2 - 2, 7, 9 and 10

• inhibits vitamin K factors II (2), VII (7), IX 9 and X (10) - coagulation
• 1972 was the year of diSCo
• factors 9, 7, 2 and 10
• proteins S and C

Question 23

In addition to inhibiting factors 2, 7, 9 and 10, what 2 other proteins is Warfarin able to inhibit?

1 - albumin
2 - protein S
3 - protein C
4 - fibrinogen

Answer 23

2 - protein S
3 - protein C

• 1972 was the year of diSCo
• factors 9, 7, 2 and 10
• proteins S and C

Question 24

Warfarin is able to inhibit the synthesis of factors 2, 7, 9 and 10 in the coagulation cascade. However, what enzyme is Warfarin able to inhibit to cause an anti-coagulability state?

1 - vitamin K hydroquinone
2 - glutamyl carboxylase
3 - vitamin K epoxide reductase
4 - quinone reductase

Answer 24

3 - vitamin K epoxide reductase

• essentially stops the recycling of vitamin K

Question 25

Is vitamin K a fat soluble vitamin?

Answer 25

- yes

Question 26

What of the following are required in the GIT for vitamin K to be digested and absorbed? 1 - gut microbiota 2 - fat 3 - bile 4 - pancreatic lipase 5 - all of the above

Answer 26

5 - all of the above

Question 27

Once digested and absorbed, typically what are the 2 sites where vitamin K is stored in the body? 1 - liver 2 - pancreas 3 - fat cells 4 - muscle cells

Answer 27

1 - liver 3 - fat cells

Question 28

What is the typical medical name given to vitamin K when administered to patients? 1 - thiamine 2 - ergocalciferol 3 - phytomenadione 4 - quinone

Answer 28

3 - phytomenadione

Question 29

In which of the following is phytomenadione (vitamin K) indicated for the use in? 1 - wernickes encephalopathy 2 - megablastic anaemia 3 - spinal cord degeneration 4 - reversal of warfarin or vitamin K deficiency

Answer 29

4 - reversal of warfarin or vitamin K deficiency - recommended in newborn babies to prevent vitamin K deficiency bleeding

Question 30

When given via IV, what is the main adverse event of phytomenadione (vitamin K)? 1 - bleeding 2 - hypertension 3 - AKD 4 - anaphylactic shock

Answer 30

4 - anaphylactic shock

Question 31

Phytomenadione (vitamin K) is given to reverse the effects of warfarin. Which of the following instances would the effect of Phytomenadione (vitamin K) be reduced? 1 - colon disease 2 - renal disease 3 - liver disease 4 - stomach disease

Answer 31

3 - liver disease - coagulation factors are made in the liver - even if you get vitamin K via IV, the liver is not working properly so factors produced by the liver would not be present

Question 32

Once Phytomenadione (vitamin K) has been administered we generally monitor the INR, which is a measure of the extrinsic pathway vs a normal control clotting ratio. How long does it take for the effects of Phytomenadione to take effect? 1 - 1-2 hours 2 - 6-12 hours 3 - 24-48 hours 4 - >72 hours

Answer 32

3 - 24-48 hours