Pulmonary Embolism

Question 1

What is pulmonary embolism and what does it cause

Answer 1

When a blood clot ( thrombus ) forms in the pulmonary arteries that blocks blood flow to lung tissue and causes a strain on RS of heart

Question 2

What usually causes pulmonary embolism

Answer 2

A deep vein thrombosis in the legs that travelled through the venous system and the right side of heart to pulmonary arteries a

Question 3

List the risk factors for pulmonary embolism or DVT ( Hint : 9 )

Answer 3

1- Immobility 
2- Recent surgery 
3- Long haul flights 
4- Pregnancy 
5- hormone therapy with oestrogen 
6- malignancy 
7- Polycythaemia 
8- Systemic lupus erythematoosus 
9- Thromophilia

Question 4

What is VTE

Answer 4

Venous thromboembolism

Question 5

What prophylactic treatment is given to reduce risk of PE or DVT

Answer 5

Low molecular weight heparin

Question 6

What treatment is given to someone at increased risk of VTE ( give drug name example )

Answer 6

1- low molecular weight heparin such as enoxaparin

2- Anti-embolic oppression stockings

Question 7

What contraindicates low molecular weight heparin

Answer 7

1- Active bleeding
2- existing coagulation with warfarin
3- NOAC

Question 8

What is a contraindication of compression stockings

Answer 8

Significant peripheral arterial disease

Question 9

How does a patient with PE present ( Hint : 8)

Answer 9

1- SOB 
2- Cough with or without blood 
3- Pleuritic chest pain 
4- Hypoxia 
5- Tachycardia 
6- Raised respiratory rate 
7- Low grade fever 
8- Haemodynamic instability causing hypotension

Question 10

What are signs specific to DVT

Answer 10

Unilateral leg swelling and tenderness

Question 11

What is Well’s score

Answer 11

Score that predicts the risk of a patient presenting with PE/DVT symptoms actuating having PE/DVT

Question 12

For diagnosing a PE what is the NICE recommendations of assessment for alternative causes

Answer 12

1- History
2- Examination
3- Chest Xray

Question 13

What is the next step if Wells score is likely

Answer 13

Preform a a CT pulmonary angiogram

Question 14

What is the next step if Wells score is Unlikely

Answer 14

preform d-dimer and if positive preform CTPA

Question 15

What are the two options to establish a definitive diagnosis of PE

Answer 15

1- CT pulmonary angiogram (CTPA)

2- Ventilation-perfusion scan ( VQ)

Question 16

Describe how a CTPA works

Answer 16

Chest scan with intravenous contrast that will highlight pulmonary arteries and thus show any blood clots.

Question 17

Describe how VQ scans work

Answer 17

A radioactive isotope and gamma camera are used to compare ventilation with perfusion of lungs. Isotopes are inhaled to fill lungs and picture is taken demonstrating ventilation. Contrast containing isotope is then injected and picture is taken showing perfusion. Two pictures are compared.

Question 18

How will a PE present in a VQ scan

Answer 18

There will be a deficit in perfusion since thrombus blocks blood flow to lung tissue. Area will be well ventilated.

Question 19

In which patients are VQ scans used

Answer 19

1- renal impairment
2- contrast allergy
3- at risk from CTPA radiation

Question 20

Why is a CTPA used more than VQ scan

Answer 20

1- more readily available
2- provides more definitive assessment
3- gives info about alternate diagnosis such as pneumonia or malignancy

Question 21

What will the ABG of a patient with PE likely show

Answer 21

Respiratory Alkalosis because high respiratory rate results in low CO2. There will also have low pO2

Question 22

What is the difference between the ABG of PE patient and hyperventilation syndrome patient

Answer 22

PE patient will have low p02 wile hyperventilation patient will have a high p02

Question 23

What is the supportive management for VTE

Answer 23

1- admission to hospital
2- oxygen
3- analgesia
4- monitoring for deterioration

Question 24

What is the initial management of VTE

Answer 24

1- Apixaban or rivaroxaban

2- Low molecular weight heparin if step 1 not suitable

Question 25

When should initial management be started if PE or DVT is suspected

Answer 25

Treatment should start immediately even if diagnosis is not confirmed yet

Question 26

What is the long term management for VTE

Answer 26

Long term anticoagulation treatment, options:
1- warfarin
2- NOAC
3- LMWH

Question 27

What is the procedure of switching from LMWH to warfarin

Answer 27

Continue LMWH for 5 days when switching to warfarin or until the INR is 2-3 for 24 hours

Question 28

What are the three options for NOAC ( DOAC )

Answer 28

1- apixaban
2- dabigatran
3- rivaroxaban

Question 29

What is the long term first line treatment for VTE if patient is pregnant or has cancer

Answer 29

LMWH

Question 30

How long should the long term anticoagulation management continue ( Hint: 3 possible situations )

Answer 30

1- 3 months if there is a reversible cause
2- 3+ months if cause is unclear and VTE is recurrent OR irreversible cause
3- 6 months in active cancer

Question 31

What is Thrombolysis

Answer 31

A treatment that involves injecting a fibrinolytic medication to rapidly dissolve clot

Question 32

When is thrombolysis used

Answer 32

When there is a large PE with haemogynamic compromise

Question 33

What is the risk with Thrombolysis

Answer 33

Significant risk of bleeding

Question 34

List examples of thrombolytic agents

Answer 34

1- Streptokinase
2- Alteplase
3- Tenecteplase

Question 35

What are the 2 ways thrombolysis can be preformed

Answer 35

1- IV with peripheral cannula

2- Directly into pulmonary arteries using central catheter

Question 36

Explain how a catheter directed thrombolysis works

Answer 36

Catheter is inserted into venous system through the right side of heart and into pulmonary arteries. Thrombolytic agent is administered directly into location of thrombus.

Question 37

What is the risk with using equipment to physically break down thrombus

Answer 37

Risk of damaging pulmonary arteries