Pulmonary Embolism Flashcards
(25 cards)
Define a pulmonary embolism
Sudden blockage of the pulmonary artery or one of its branches by an embolus
What are the causes of PE?
Emboli of a thrombus, solid, liquid or gas
What is the most common site of thrombosis formation that leads to PE?
DVT in deep veins of leg
How does PE lead to increased Right Ventricular failure?
Increased vascular resistance → increased pulmonary artery pressure → increased right ventricular pressure
What is the most common site of embolus formation in PE?
Femoral vein
What are the 3 types of PE?
- Low risk
- Submassive
- Massive - rapidly fatal, patient is haemodynamically unstable
What renal condition can lead to a PE and why?
Nephrotic syndrome, causes loss of protein in urine including antithrombin III, protein C and S
What is the most common location of thrombosis formation in a patient with nephrotic syndrome?
Renal vein
What condition can happen in the case of left renal vein thrombosis but not the right?
Left sided varicocele
What is a complication of left sided varicocele?
Can lead to male infertility
What are the 5 differentials for cough with or without dyspnoea?
- Obstructive Lung Disease
- Restrictive lung disease
- Pulmonary vascular abnormality (i.e PE)
- Infections
- Malignancy
What are the symptoms of a PE?
- Sudden onset dyspnoea
- Pleuritic chest pain
- Haemoptysis of pink frothy sputum
What are the signs of a PE?
- Sinus tachycardia
- Sudden onset tachypnoea
- Unilateral calf swelling
- Tender, hard
- Collapse if large PE
- Hypotensive
- Raised JVP
- Loud P2 sound on auscultation
- Pleural rub
- Additional S3 sound
What is Virchow’s triad?
3 factors contributing to thrombosis
* Blood stasis
* Endothelial damage
* Hypercoagulation
What is the gold standard to diagnose a DVT?
Doppler ultrasound aka duplex ultrasound
What is the role of D-dimer in DVT diagnosis?
Used to EXCLUDE DVT
.What investigations are done for a PE?
- ECG - S1 Q3 T3 or sinus tachycardia
- ABG
- Blood tests (FBC, CRP to rule out infection. U+E’s as patient will need CTPA. Troponin and NT BNP as PE can cause right sided heart strain)
- X-ray
*CTPA - If contrast allergy -> V/Q SPECT scan
What are the findings on X-ray that PE could cause?
X RAY USUALLY NORMAL IN PE
* Hampton’s hump
* Westermark’s sign
* Palla’s sign
* Consolidation
* Elevated hemidiaphragm
What is the PERC rule-out criteria?
If the patient doesn’t fulfill any of the PERC criteria, then it is most likely NOT PE
What is the Well’s Criteria for PE?
- Clinical signs of DVT - 3 pts
- No diagnosis more likely than PE- 3 pts
- Tachycardia >100 - 1.5 pts
- Recent major surgery/immobilisation in last 4 weeks - 1.5 pts
- Previous history of DVT/PE - 1.5 pts
- Haemoptysis - 1 pt
- Active cancer - 1 pt
What is the long term management for PE?
- DOAC
- LMWH first line in pregnancy
- Warfarin 1st line in antiphospholipid syndrome
What should be suspected if a patient suddenly needs oxygen and collapses?
PE, if X-ray rules out infection
What is the Wells Score?
Used to decide investigations for suspected PE
‘1 Direction Thinks I Have Hidden Motives’
1- No.1 diagnosis is PE (3 points)
D- DVT clinical signs (3)
T- Tachycardia (1.5)
I - Immobilisation (1.5)
H - History of PE/DVT (1.5)
H- Haemoptysis (1)
M - Malignancy (1)
> 4 points = order CTPA
4 points or less = d-dimer
If d-dimer +ve -> CTPA
If d-dimer -ve -> stop anticoagulation and consider alternative diagnoses
Management of a pulmonary embolism?
If PE suspected -> anticoagulation with LMWH, e.g. enoxaparin OR DOAC and stopped if PE ruled out
When PE confirmed -> continue on a DOAC or LMWH/warfarin if DOAC is contraindicated
If massive PE -> IV alteplase. If thrombolysis contraindicated offer Embolectomy, or Catheter derived thrombolysis (use CDT if high bleeding risk)
THEN…
If provoked PE -> continue anticoagulation for 3 months or 3-6 months if also active cancer
Unprovoked PE -> continue anticoagulation for 3-6+ months
