Pulmonary Embolism Flashcards
Define Pulmonary Embolism
Occlusion of the pulmonary vessels as a consequence of a thrombus travelling to the pulmonary vascular system
Aetiology of Pulmonary Embolism
thrombus formation in the deep veins which travels to the pulmonary vessels and occludes them. 95% are formed from a DVT in the lower limbs.
May also develop from the right atrium in AF
Others: amniotic fluid, air, fat, tumour
Thrombus formation = Virchow’s triad (stasis, vessel injury, hyper-coagulability)
Risk factors for Pulmonary Embolism
Previous surgery Immobility Obesity COCP Heart failure Malignancy
Symptoms of Pulmonary Embolism
Small: asymptomatic
Moderate: sudden onset dyspnoea, cough, haemoptysis and pleuritic chest pain
Large: moderate PE + severe central pleuritic chest pain, shock, collapse, acute RHF, sudden death
Signs of Pulmonary Embolism
Small: often none
Moderate: tachypnoea, tachycardia, pleural rub, low sats
Massive: Shock, cyanosis, RHF (Raised JVP, left parasternal heave, accentuated S2)
Investigations for Pulmonary Embolism
Wells score (also PESI, revised Geneva) Low probability (4 or less): D-dimer High (>4): CTPA
D-dimer +ve -> CTPA
CTPA -ve -> Consider proximal leg vein USS
ABG: hypoxaemia and hypocapnia
Clotting screen: for anticoagulation considerations
ECG: Sinus tachycardia (or normal), RAD or BBB, S1Q3T3, T wave inversion, P pulmonale,
CXR: often normal
CTPA: Thrombus visual in pulmonary artery
V/Q scan: Identifies PE (used in renal failure)
Pulmonary angiogram: Gold standard but invasive
Doppler USS lower limb: VTE
Echo: May show right heart strain and dilatation, abnormal ejection pattern (60-60 sign and hypokinesis and reduced contractility (used in haemodynamically unstable patients)
What is the PERC
PE rule out criteria
Used to rule out PE
0 points - can exclude
Management for Pulmonary Embolism
As soon as suspected: offer LMWH/DOAC -> rivaroxaban favoured
If CTPA cannot be done immediately or D-dimer result will not be back in 4-hours -> anticoagulate with rivaroxaban
Haemodynamically stable Oxygen Anticoagulation with heparin or LMWH Change to oral warfarin (INR 2-3) for minimum 2 months Analgesia
Haemodynamically unstable Resuscitate Oxygen IV fluid resus Thrombosis is with tPA (50mg bonus)
Surgery:
Embelectomy
IV filters
What is the prophylactic and follow up management for Pulmonary Embolism
Prophylaxis:
Graduated pressure stockings TEDs
High risk - heparin prophylaxis
Early mobilisation + hydration
Follow-up:
Provoked -> anticoagulants for 3 months
Unprovoked -> anticoagulants for 6 months
Complications of Pulmonary Embolism
Death
Pulmonary infarction
Pulmonary hypertension
Right heart failure
Prognosis for Pulmonary Embolism
30% untreated mortality
8% mortality with treatment
Increases risk of future thromboembolic disease
