Pulmonary Embolism (PE) Flashcards
What is PE?
Condition when 1+ emboli (arising from thrombus formed in veins) obst Pulmonary Arteries –> Resp dysfunction
(usually from DVT in legs)
What is the passage of the thrombus before it reaches pulmonary circulation? (3 things)
- Veins (breaks off from here)
- Right side of heart
- Pulmonary Circulation
What are the Risk Factors for a PE? (10 things)
- Age
- Pregnancy
- COCP / Hormone Therapy
- Obesity
- Immobility (Long flights / casts)
- Surgery (esp pelvic / orthopaedic)
- Trauma
- DVT Hx
- Cancer
- Thrombophilia (e.g antiphospholipid syndrome)
- Leg / Hip # (FAT EMBOLISM)
same as DVT RFs
What is the pathophysiology of the LUNG clartation that happens in PE? (4 steps)
V/Q (ventilation / perfusion) mismatch
- Ventilation WITHOUT Perfusion (Alveolar DEAD SPACE)
- Inflamm mediators released
- Vasoconstriction
- Decreased blood flow to Alveoli
(Alveoli considered DEAD SPACE bc still ventilated but not perfused)
What is the pathophysiology of the RIGHT HEART clartation (aka Haemodynamic Instability) that happens in PE? (7 steps)
- PE occur in Pulmonary Arteries from R Heart to Lungs
- PE –> Increased Pulmonary Vascular Resistance (PVR)
- Decreased ejection from Right Ventricle
- Increased Central Venous Pressure (CVP)*
- RV strain + distension
- RV decreased contractility
- RHF
*(bc blood coming bk from body into R heart can’t push against da resistance)
What is the pathophysiology of the LEFT HEART clartation (aka Haemodynamic Instability) that happens in PE? (5 steps)
RHF –> LHF
- Decreased ejection from Right Ventricle
- Less blood going to lungs –> less blood returning to L Heart
- Decreased Left Ventricular End-Diastolic Volume (LVEDV)
- Decreased CO
- Hypotension + Tachycardia
What are the CF of PE? (8 things)
- Asymptomatic (if small emboli)
- Low grade Fever
- SOB / Tachypnoea
- Cough (+/- haemoptysis)
- Pleuritic Chest pain
- Crackles
- Haemodynamic instability –> Hypotension + Tachycardia
- DVT signs (unilateral leg swelling + tenderness)
What are the ECG changes seen in a PE? (3 things)
- Sinus tachycardia (44%) (bc haem instab)
- T Wave inversion (in V1-4) (34%) (bc RV strain)
- RBBB (18%)
What investigations should you do for sus PE? (4 things)
- Well’s Score for PE (bit different to DVT one)
- CT Pulmonary Angiogram (CTPA)
- V/Q Scan
- D-Dimer
Bold ones = definitive diagnosis
What does the Well’s Score for PE tell you in sus PE?
The likeliness of a PE
4+ score = DVT likely
What does the Well’s Score for PE include? (5 things)
- Clinical signs of DVT (3 points)
- Recent surgery (1.5 points)
- Tachycardia (1.5 points)
- Haemoptysis (1 point)
- Cancer (1 point)
Ders more but jus remember dese 5
What should you do if the Well’s Score is 4+, aka PE = likely?
CT Pulmonary Angiogram (CTPA)
Who should you NOT do CTPAs on? (3 things)
What scan should you do instead if there Well’s Score is 4+, aka PE is likely?
- Renal Impairment
- Contrast allergy
- Risk from radiation
Do V/Q Scan on dem instead
What should you do if the Well’s Score is 3-, aka PE = unlikely?
D-Dimer
And if positive, do a CTPA (or V/Q Scan)
What is a CT Pulmonary Angiogram?
CT of chest w IV contrast
Lets u see any clots in pulmonary arteries
What are the FIRST LINE management options for PE?
DOACs (Apixaban / Rivaroxaban)
same as DVT
What are the SECOND LINE management options for PE? (2 things)
LMWH (Low Molecular Weight Heparin)
with
Dabigatran / Edoxaban (DOACs) OR Warfarin (Vit K antagonist)
same as DVT
What is the FIRST LINE treatment for PE but has severe Renal impairment / Antiphospholipid syndrome?
LMWH / Unfractionated Heparin
(DOACs not safe in Renal Impairment bc meant to be cleared by Kidney)
same as DVT
What is the FIRST LINE treatment of PE in Pregnancy / Breastfeeding?
LMWH
DOACs not safe in pregnancy / breastfeeding
same as DVT
How long should PE patients take their Anticoagulation meds for?
At least 3 months
After 3 months of anticoagulation meds, what determines if a PE pt should carry on / stops meds?
If DVT–>PE was provoked by an acc event (e.g immobilisation after surgery) (can stop)
or if they jus have acc risk factors (carry on taking for 3 more months)
After 6 month course of anticoagulation meds (bc DVT–>PE was unprovoked), what should you do for a PE pt who will now stop taking meds? (2 things)
Test them for:
- Antiphospholipid syndrome (check for antibodies)
- Hereditary thrombophilias (only if have 1st Degree FHx of DVT / PE)
What is the management option for a MASSIVE PE causing Haemodynamic Instability?
Thrombolysis
What is Thrombolysis?
Injecting Fibrinolytic meds to break down massive PE clots
What is an example of a Fibrinolytic med?
Streptokinase
How is Thrombolysis performed? (2 ways)
- IV using Peripheral Cannula
- Catheter Directed Thrombolysis: directly into Pulm arteries using Central Catheter
