PE and pulmonary hypertension Flashcards
Is a proximal (ileofemoral) or distal (popliteal) most likely to embolise?
Proximal - also more likely to lead to chronic venous insufficiency and venous leg ulcers
what is the first line investigation for DVT?
-ultrasound doppler leg scan (will exclude popliteal cyst or pelvic mass)
What are the differences seen clinically between a large/medium/small PE?
Large- cardiovascular shock, low BP, central cyanosis, sudden death
Medium-pleuritic pain, haemoptysis, breathless
Small recurrent- progressive dyspnoea, pulmonary hypertension and right heart failure
What are the ten risk factors for DVT and PE?
Thrombophilia- FH,freq,site,age
Contraceptive pill (particularly if smokes),HRT
Pregnancy
Pelvic obstruction-eg uterus,ovary,lymph nodes
Trauma-eg RTA
Surgery- eg pelvic,hip,knee
Immobility-eg bed rest,long haul flights
Malignancy
Pulmonary hypertension/vasculitis
Obesity
What are the five clinical features of PE?
Shortness of breath (often acute onset) Chest pain (pleuritic) Haemoptysis Leg pain/swelling Collapse / Sudden death
What are 8 clinical signs of PE?
Tachycardia, tachypnoea, cyanosis,fever, Low BP, crackles, rub, pleural effusion
What is seen on ABG’s and CXR for PE?
Arterial blood gases (ABGs)
low PaO2 , low SaO2 (Type 1 resp failure:PaCO2 normal or low)
CXR:
Normal early on before infarction
Basal atelectasis, consolidation.
Pleural effusion
What is seen on ECG and isotope lung scan for PE? what is the blood test used to help diagnose PE?
ECG: Acute Right heart strain pattern (S1Q3T3; T inversion in V1-3)
Isotope lung scan (Ventilation/Perfusion: V/Q
Sensitive for small peripheral emboli
Perfusion defect before infarction
Perfusion+Ventilation matched defect after infarction
D-dimers usually raised
Why are CT pulmonary angiogram and echocardiogram used in the investigation of PE?
CT pulmonary angiogram (CTPA) to image pulmonary artery filling defect
to pick up larger clots in proximal vessels
Echocardiogram to measure pulmonary artery pressure and right ventricular size; acute dilatation of RV in keeping with acute PE
if no obvious underlying cause for PE:
How would you investigate for cancer?
What other things would you screen for (2)?
Consider cancer – Clinical exam; CXR, PSA, CA125, CEA, Pelvic USS or CT Abdo/pelvis
Autoantibodies (SLE) – Antinuclear, Anti-Cardiolipin Abs
Thrombophilia screen
Anti-thrombin-III deficiency ,Protein C or S deficiency, Factor V Leiden; increased VIII
How are DVT’s prevented(5)?
Early post-op mobilisation
TED compression stockings
Calf muscle exercises
Subcutaneous low dose low mol wt heparin perioperatively (Dalteparin- Fragmin)
Novel Oral Anticoagulant (NOAC) medication
Dabigatran - direct thrombin inhibitor
Rivaroxaban/Apixaban - direct inhibitor of activated factor Xa
What treatment is used as standard for PE/DVT?
Anticoagulation prevents clot propagation: tips balance to thrombolysis and body dissolves clot
Rarely IV heparin
SC Low mol wt heparin (LMWH e.g. dalteparin-fragmin) –once daily injection ,no monitoring required
Also start warfarin at same time as heparin
Or instead use oral thrombin inhibitor (dabigatran) or factor X inhibitor (Rivaroxaban) on its own from the start –less hassle and in most cases as effective as heparin/warfarin
Oral warfarin-takes 3 days-antagonises Vit K dependent prothrombin
After 3-5 days stop heparin-when INR>2
Or use NOACs without LMWH
Continue Warfarin for 3-6 months
Monitor Warfarin with INR-Target range 2.5-3.5
What treatment is used for large life-threatening PE?
Thrombolysis- tissue plasminogen activator (tPA)
Tenecteplase
Only for large life threatening PE-i.e. low BP and severe hypoxaemia due to main pulmonary artery occlusion
In the management of PE, when would an IVC filter be used to prevent embolisation from large ileofemoral/IVC clot?
for recurrent PE’s
is the pulmonary vascular system high or low pressure? when is this classed as pulmonary hypertension?
Normally a high flow, low pressure system
Normal mean pulmonary arterial pressure (mPAP) is 12-20 mmHg
mPAP >25 mmHg = pulmonary hypertension
what are three causes of pulmonary venous hypertension?
LVSD - ischaemic
Mitral Regurgitation / Stenosis
Cardiomyopathy-e.g. alcohol ,viral
What are 7 causes of pulmonary arterial hypertension?
Hypoxic – COPD , OSA , Pulmonary fibrosis
Multiple PE – chronic thromboembolic PH (CTEPH)
Vasculitis –e.g. SLE , PAN ,Systemic Sclerosis
Drugs e.g. appetite suppressants - fenfluramine and derivatives
HIV
Cardiac Left to right shunt – ASD, VSD
Primary pulmonary hypertension
What is cor pulmonale?
Right heart disease secondary to lung disease
Fluid retention due to hypoxia +/- right heart failure
E.g secondary to COPD
What are 7 clinical signs of pulmonary hypertension and right heart failure?
Central cyanosis if hypoxic
Dependent oedema
Raised JVP with V waves (due to secondary tricuspid regurg)
Right ventricular heave at left parasternal edge
Murmur of tricuspid regurgitation
Load P2
Enlarged liver (pulsatile)
How is primary pulmonary hypertension diagnosed? what are the 2 clinical features? what is the prognosis without treatment?
Diagnosis by exclusion of other secondary causes
Progressive SOBOE and signs of right heart failure
Poor prognosis of 3 years without treatment
what are the three different ways to treat primary pulmonary hypertension?
Pharmacologic Treatment:
- prophylactic anticoagulation (warfarin)
- O2 if hypoxic
Pulmonary Vasodilators:
- Ca2+ channel blockers (oral nifedipine ,diltiazem)
- Endothelin antagonist (Oral Bosentan,Macitentan)
- PDE5-inhibitor (Oral Sildenafil/Tadalafil)
- Prostanoids (IV Epoprostenol or Inhaled Iloprost )
- Soluble Guanylate Cyclase stimulator (oral Riociguat)
Lung transplant
what has to be present for a pulmonary infarct to take place?
Embolus necessary but not sufficient
Bronchial artery supply compromised (eg in cardiac failure)
what score is used if P.E is clinically likely?
Two level wells score
Clinical signs and symptoms of DVT (minimum of leg swelling and pain with palpation of the deep veins) 3
An alternative diagnosis is less likely than PE 3
Heart rate > 100 beats per minute 1.5
Immobilisation for more than 3 days or surgery in the previous 4 weeks 1.5
Previous DVT/PE 1.5
Haemoptysis 1
Malignancy (on treatment, treated in the last 6 months, or palliative) 1
If the score is above 4 what is done?
= PE is ‘likely’ (more than 4 points) arrange an immediate computed tomography pulmonary angiogram (CTPA). If there is a delay in getting the CTPA then give low-molecular weight heparin until the scan is performed.
If the score is below 4 what is done?
a PE is ‘unlikely’ (4 points or less) arranged a D-dimer test. If this is positive arrange an immediate computed tomography pulmonary angiogram (CTPA). If there is a delay in getting the CTPA then give low-molecular weight heparin until the scan is performed.
If the patient has allergy to contrast/renal failure what is done instead of CTPA?
V/Q scan
