Thrombolytic agents

Question 1

How long is it from the formation of the blood clot before the fibrinolysis (degradation of fibrin mesh) gradually breaks down the blood clot?

1 - 12 hours
2 - 24 hours
3 - 48 hours
4 - 72 hours

Answer 1

3 - 48 hours

Question 2

Following healing the body will decide to break down any blood clots that are no longer needed, called fibrinolysis. This normally begins within 48 hours of blood clot formation. Which protein produced by the liver is crucial for starting fibrinolysis?

1 - factor III (3)
2 - plasminogen
3 - tissue plasminogen activator
4 - plasmin

Answer 2

2 - plasminogen

Question 3

Plasminogen, produced by the liver is crucial for starting fibrinolysis in the fibrinolysis pathway. Endothelial cells produce what that is able to convert plasminogen into its active form plasmin?

1 - factor III (3)
2 - protein S
3 - tissue plasminogen activator (tPa)
4 - protein C

Answer 3

3 - tissue plasminogen activator (tPa)

• used clinically as a clot buster to dissolve pathological blood clots

Question 4

During secondary haemostasis endothelial cells are exposed to coagulation factors (factor Xa and thrombin) and the production of tissue plasminogen activator (tPa) is increased. What 2 other molecules do endothelial cell produce that is able to inhibit tPa and plasmin, ensuring we are able to clot and stop bleeding?

1 - protein S
2 - plasminogen activator inhibitor 1
3 - protein C
4 - antiplasmin

Answer 4

2 - plasminogen activator inhibitor 1

4 - antiplasmin

Question 5

Once plasmin is activated how does it degrade clots?

1 - acts as a protease acting on fibrin
2 - acts as a reductase
3 - induced apoptosis in platelets
4 - initiates shedding of endothelium cells

Answer 5

1 - acts as a protease acting on fibrin

Question 6

Tissue plasminogen activator (tPa) is responsible for converting plasminogen into plasmin. What other proteins / factors are able to activate plasmin in addition to tPa?

1 - factor IXa (9a)
2 - XIIa (12a)
3 - protein C
4 - all of the above

Answer 6

4 - all of the above

Question 7

Which of the 2 core thrombolytic agents that we need to know?

1 - Streptokinase
2 - Tinzaparin
3 - Alteplase
4 - Tenecteplase

Answer 7

3 - Alteplase
4 - Tenecteplase

• both end in teplase

Question 8

The 2 drugs are core thrombolytic agents are - Alteplase and Tenecteplase. What is the mechanism of action of these 2 drugs?

1 - increases plasminogen 2 - inhibits antiplasmin
3 - inhibits plasminogen activator inhibitor 1
4 - binds to fibrin proteins and activates plasminogen, allowing plasmin to break down clot

Answer 8

4 - binds to fibrin proteins and activates plasminogen, allowing plasmin to break down clot

Question 9

The thrombolytic agent Alteplase is indicated to be administered IV in patients with acute ischaemic strokes. However, to have these beneficial effects they have to be administered in what time frame?

1 - <4.5 hours
2 - <10 hours
3 - <24 hours
4 - <48 hours

Answer 9

1 - <4.5 hours

• mechanical thrombectomy can also be given

Question 10

Although percutaneous coronary interventions are now the main treatment for patients with ST-elevation ACS, thrombolytic agent can also be given and will improve outcomes if given in what time period?

1 - <4.5 hours
2 - <12 hours
3 - <24 hours
4 - <48 hours

Answer 10

2 - <12 hours

Question 11

Although percutaneous coronary interventions are now the main treatment for patients with ST-elevation ACS, thrombolytic agent can also be given and will improve outcomes if given within 12 hours. They do however, need to be given with which 2 other drug classes?

1 - ACE inhibitors
2 - loop diuretics
3 - anti-platelets
4 - anti-coagulants

Answer 11

3 - anti-platelets
4 - anti-coagulants

• the combination of these 3 classes of drugs does increase the risk of haemorrhage

Question 12

Which of the following are thrombolytic agents given in, reducing the size of the blood clot?

1 - bells palsy
2 - increased jugular venous pressure
3 - CKD
4 - PE

Answer 12

4 - PE

Question 13

Which of the following are common adverse events from thrombolytic agents?

1 - hypotension
2 - nausea
3 - vomiting
4 - all of the above

Answer 13

4 - all of the above

Question 14

In which of the following should thrombolytic agents be stopped?

1 - serious bleeding
2 - allergic reaction
3 - cardiogenic shock
4 -cardiac arrest
5 - all of the above

Answer 14

5 - all of the above

Question 15

What 2 of the following are contraindications for the use of thrombolytic agents?

1 - PE
2 - ACS
3 - bleeding
4 - intracranial haemorrhage

Answer 15

3 - bleeding

4 - intracranial haemorrhage
- needs to be ruled out using a CT or MRI

Question 16

Which drug has been shown to increase the risk of an anaphylactoid reaction when combined with thrombolytic agents?

1 - anti-platelets
2 - ACE inhibitors
3 - anticoagulants
4 - antidepressants

Answer 16

2 - ACE inhibitors

Question 17

Which 2 of the following is how thrombolytic agents are typically administered?

1 - orally
2 - IV
3 - injection IV
4 - suppository

Answer 17

2 - IV
3 - injection IV

Question 18

Administration of thrombolytic agents should only be used in high dependency areas with experts in its use. Once administered how often must the patient be monitored?

1 - every 15 minutes
2 - every 30 minutes
3 - every hour
4 - every 2 hours

Answer 18

1 - every 15 minutes

• must be performed for the 1st 2 hours