Pulmonary embolism Flashcards
What is a PE
life threatening condition
results from dislodged thrombi occluding pulmonary vasculature
right heart failure and cardiac arrest may ensue if not aggressively treated
What are risk factors for PE
SPAM-HD
surgery
pregnancy
age
malignancy
hormones - COCP/HRT
DVT
What are key diagnostic factors someone with a PE may present with
pleuritic chest pain
dyspnoea
haemoptysis
collapse if severe
tachycardia
tachypnoea
fever
What is PERC
Pulmonary embolism rule-out criteria
used to exclude PE in patient known to have a low pre-test probability <15%
What is the criteria for PERC
Age>50
heart rate >100
o2 saturations <94%
previous DVT/PE
recent surgery/trauma in last 4 weeks
haemoptysis
unilateral leg swelling
oestrogen use
What should be performed if a PE is suspected
2-level PE Wells score
What is the criteria for 2-level PE Wells score
Clinical signs and symptoms of DVT= 3 points
An alternative diagnosis is less likely than PE=3 points
Heart rate> 100bpm - 1.5
Immobilisation for more than 3 days / surgery in previous 4 weeks - 1.5
Previous DVT/PE- 1.5
haemoptysis - 1
malignancy -1
How do you interpret the 2 level PE Wellls score
PE likely - more than 4 points
PE unlikely -4 points or less
What investigations are required if PE is likely
Computed tomography pulmonary angiogram - CTPA
- if positive PE diagnosed
-if negative consider proximal leg vein ultrasound if DVT suspected
Interim therapeutic anticoagulation - DOAC such as apixaban or rivaroxaban
What investigations are required if PE is unlikely
D dimer test
if positive - CTPA
if negative , stop anticoagulation
When do you not use a CTPA scan
if patient has renal impairment do a V/Q scan
What other investigations should be carried out
ABG
ECG
CXR-
What may be seen on an ECG of someone with PE
sinus tachycardia !!!
may see right branch bundle block, right axis deviation
-large S wave in lead I
-Large Q wave in lead II
-Inverted T wave in lead III
What may be seen on CXR for someone with a PE
typically normal
may have wedge shaped opacification
Westermark’s sign a chest x-ray finding of oligaemia (clarified area) distal to a large vessel that is occluded by a pulmonary embolus.
How do you manage patient with PE if hemodynamically unstable
SBP<90
THROMBOLYSIS - alteplase
( fibrinolytic agent )
respiratory support
unfractionated heparin
then switch to DOAC - apixaban or rivaraoxaban
