Pulmonary Embolism (PE)

Question 1

Where do PE come from?

Answer 1

Anywhere in venous system
90% systemic veins
10% R.Heart

Majority are Abdominal in origin.
DVT also common
Axillary not uncommon

Question 2

Rare emboli materials (not VTE)

Answer 2

Fat
Tumour
Foreign Body
Amniotic Fluid

Question 3

Virchow’s Triad of thrombus formation

Answer 3

Hypercoagubility
Endothelial Injury
Disturbed Blood flow

Question 4

Risk Factors PE

Answer 4

Reduced mobility: post surgery / comorbidity / long haul travel / Functional
Active Ca
Ca treatment
>60yrs Age
Dehydration
Thrombophillias
Obesity
FH
HRT/Oestrogen usage
Long Bone fractures
IV drug usage
Pregnancy
DVT
Varicose vein Phlebitis

Question 5

Pathophysiology PE

Answer 5

lung tissue distal to embolus is ventilated but not perfused
Increase in dead space and decrease in Gas exchange
Ventilation/ perfusion mismatch
Lung tissue denatures shortly (and eventually necroses) and stops producing surfactant causing alveolar collapse
decreases area of pulmonary arterial bed increasing P arterial pressure
decreases cardiac output

Question 6

Types of PE

Answer 6

1. Asymptomatic (60% of people will have micro-emboli)
2. Common PE
3. Massive PE (CO affected)

Question 7

Presentation of common PE

Answer 7

Sudden unexplained breathlessness
sometimes accompanied by pleuritic pain, heamoptysis and signs of DVT
TACHY, LOCALISED PLEURAL RUB AND COARSE CRACKLES, PYREXIA

Question 8

ECG changes in PE

Answer 8

1. Sinus Tachycardia (by far most common)
2. New onset AF
3. Tall peaked P waves (P. Pulmonale) Right axis deviation and R Bundle Branch Block

Question 9

Massive PE presentation

Answer 9

sudden collapse/ presyncope
cardiac chest pain and shock
O/E:
raised JVP with a wave
Gallop rhythm
Split Heart Sounds
R Ventricular heave

Question 10

Management of PE

Answer 10

1. ABCDE
2. Wells Score
3. Investigations
4. If confirmed PE rest, anticoagulate.
5. fibrinolyis or surgery if appropriate

Question 11

Wells Score for PE

Answer 11

< 3 = unlikely PE. D Dimer to exclude and consider differentials
>4 = Likely PE- CTPA