Peripheral Vascular Disease Flashcards
When does intermittent claudication occur?
When there is insufficient blood flow to the muscles in the legs during exercise
What is intermittent claudication?
Ischaemic pain in the legs exacerbated or brought on by exercise due tot he muscles requiring more oxygen than the vasculature can supply
What are the four main pulses in the lower limbs?
- Femoral
- Popliteal
- Posterior tibial
- Dorsalis pedis
Which two general approaches to investigation could be taken for suspected lower limb ischaemia?
- Non-invasive investigation
2. Invasive investigation
Give two examples of non-invasive investigation in relation to lower limb ischaemia
- Measurement of ABPI (ankle-brachial pressure index)
2. Duplex ultrasound scanning
Give three examples of invasive investigation in relation to lower limb ischaemia
- Magnetic resonance angiography
- CT angiography
- Catheter angiography
What is angiography ?
Radiography of blood/lymph vessels after introduction of a radiopaque substance (contrast)
Why is a normal ankle- brachial pressure index (ABPI) very close to 1?
ABPI is calculated by dividing ankle blood pressure over brachial pressure. Ideally, blood pressure should be the same at both locations (giving ABPI of 1). In PVD, blood flow is reduced to the lower limbs so blood pressure is lower, which gives a lower ABPI
What is the normal ABPI range?
0.9-1.2
What is the ABPI range for someone with claudication?
0.4-0.85
What is associated with diabetes that can lower ABPI?
Calcified vessels- lowers peripheral artery blood pressures
How does exercise impact ABPI?
Normally it will increase, but in patients with claudication it will decrease
Which two elements are incorporated into duplex ultrasound scanning?
- Grayscale- visualises structure, plaques and cross sections of narrowed vessels
- Colour- allows for visual representation of blood flow
What does magnetic resonance angiography allow viewing of?
Occlusions and aneurysms
How does CT angiography work?
A range of X-rays are beamed from a rotating device to create a 3D image
Contrast is added to vessels
What is a key use for catheter angiography?
Visualisation of coronary arteries
How is lower limb ischaemia slowed?
- Smoking cessation
- Lowering lipids
- Antiplatelets
- Hypertension management
- Good diabetic management
- Good lifestyle choices e.g. diet/ physical exercise
How can symptoms for lower leg ischaemia be improved?
- Exercise training (lower oxygen tolerance)
- Drugs- Cliostazol
- Angioplasty or stunting increases lumen diameter
- Surgery- endarterectomy (removes plaque) or bypass (uses prosthetic vein)
What symptoms indicate severe ischaemia and tissue damage ?
- Ulcers
- Gangrene
- Pain at rest
What are the main risk factors for critical limb ischaemia?
- Smoking
2. Diabetes
How can critical limb ischaemia be treated?
- Painkillers
- Angioplasty/stenting
- Surgical reconstruction
- Amputation
