Peripheral Vascular Disease Flashcards
What does the abdominal aorta become at its bifurcation
common iliac arteries
What do Common Iliac arteries give rise to
Internal Iliac artery
External Iliac artery (continues as main vessel)
At groin crease, what does external iliac artery become
Common femoral artery (branch of profunda femoris artery)
What does the Common femoral artery become
Superficial femoral artery
What does suprficial femoral artery become at knee crease
Popliteal artery
What does popliteal artery bifurcate into
Tibio-peroneal trunk
Anetrior tibial artery
What does tibio-peroneal trunk bifurcate into
Peroneal artery
Posterior tibial artery
What does peripheral vascular disease refer to?
Partial blockage of leg
or peripheral vessels by an
atherosclerotic plaque and or resulting thrombus resulting in insufficient perfusion of the lower limb resulting in
LOWER LIMB ISCHAEMIA
Is peripheral vascular disease more common in men or women
Men
What arteries (around lower limb) are generally affected by peripheral vascular disease or atherosclerosis
Aorta-iliac
Infra-inguinal
Peripheral vascular disease risk factors
- Smoking
- Diabetes
- Hypercholesterolaemia
- Hypertension
- Physical inactivity
- Obesity
Cause of peripheral vascular disease
Atherosclerosis of arteries distal to aortic arch
Peripheral vascular disease - oxygen pressure at rest
Normal
Peripheral vascular disease - oxygen pressure when begin exercise
Normal
Peripheral vascular disease - oxygen pressure when do moderate exercise
Normal
Peripheral vascular disease - oxygen pressure when do hard exercise
Low
Peripheral vascular disease - oxygen pressure when have short rest or long rest
Short rest - normal
Long rest - normal
Features of mild ischaemia
Stress-induced physiological malfunction
Exercise induced angina
Intermittent claudication
*What is Intermittent claudication
Cramping pain that is induced by exercise and relieved by rest.
Occurs when anaerobic metabolism comes into effect when oxygen demand outstrips supply
Features of intermittent claudication
Pain distal to site of atheroma.
Pain is result of lactic acid production.
Caused by inadequate blood supply to the affected muscles resulting in moderate ischaemia.
Leg pulses are often absent and feet may be cold.
In what muscles is intermittent claudication most common seen
Calf and leg muscles as a result of atheroma in the legs.
Oxygen pressures in different activities with intermittent claudication: At rest Begin exercise Moderate exercise Hard exercise Short rest Long rest
At rest - normal Begin exercise - normal Moderate exercise - low Hard exercise - low Short rest - low Long rest - normal
Describe features of critical limb ischaemia
• Blood supply is BARELY ADEQUATE to allow basal
metabolism
• No reserve available for increased demand
• Rest pain that is typically NOCTURNAL
• Risk of gangrene and/or infection
• CHRONIC CONDITION and the MOST SEVERE clinical
manifestation of peripheral vascular disease
Oxygen pressures in different activities with critical limb ischaemia: At rest Begin exercise Moderate exercise Hard exercise Short rest Long rest
At rest - low Begin exercise - low Moderate exercise - low Hard exercise - low Short rest - low Long rest - low
What diseases can result from moderate ischaemia in peripheral vascular disease
Ischaemic cardiac failure
Critical limb ischaemia
Vascular dementia
What diseases can result from severe ischaemia in peripheral vascular disease
Infarction
Gangrene
General symptoms of chronic lower limb ischaemia
Absent femoral, popliteal or foot pulses
Cold, white legs
Differential diagnosis of chronic lower limb ischemia
Osteoarthritis of hip/knee due to knee pain at rest
Peripheral neuropathy - associated with tingling
*Diagnosis of chronic lower limb ischemia
Colour duplex ultrasound (1st line)
ESR/CRP (to exclude arteritis - in which results would be raised)
FBC - look at Hb levels to exclude anaemia or polycthaemia (increased RBCs)
ECG - cardiac ischaemia
MRI/CT angiography to assess extent and location of stenoses and quality of distal vessels (if considering intervention)
How can you analysis severity of chronic lower limb ischaemia
Ankle/Brachial Pressure Index (ABPI)
Measurement of the cuff pressure at which blood flow is detectable by Doppler (ultrasound that measures blood flow) in the posterior tibial or anterior tibial arteries compared to the brachial
artery
What value range would classify intermittent claudication on and Ankle/Brachial Pressure index
0.5 to 0.9
What value range would classify critical leg ischaemia on and Ankle/Brachial Pressure index
<0.5
Causes of acute lower limb ischaemia
Embolic disease (commonly due to cardiac arrhythmias and cardiac thrombus or secondary to aneurysm thrombus or thrombus on atherosclerotic plaques)
Thrombotic disease (more common - forms in patients who are hypercoagulable due to malignancy or thrombophilia effects)
*Symptoms of acute lower limb ischaemia
Pain Pallor Perishing cold Pulseless Paralysis Paraesthesia (pins and needles or abnormal tinging/prickling)
The more Ps present the more sudden and complete your ischaemia
Treatment of peripheral vascular disease
Risk factor modification
Revascularisation for critical ischaemia
Risk factor modification for treatment of peripheral vascular disease
Smoking cessation
Treat hypertension, hyperlipidemia and diabetes
Antiplatelet agent such as P2Y12 inhibitor e.g. Clopidogrel to prevent progression and minimise risk
Exercise and weight loss
Why is smoking bad for peripheral vascular disease
Every time you smoke, small vessel in the muscles near to ischaemia (that provide ‘back up supply’) contract in response to nicotine and tobacco
resulting in a reduction in blood flow through them (bad)
*Describe how revascularisation can be used to treat critical ischaemia
Percutaneous transluminal angioplasty (essentially squash plaque and thus increase perfusion and reduce ischaemia)
Bypass procedure
Amputation if severe
Describe treatment of acute ischaemia
SURGICAL EMERGENCY requiring REVASCULARISATION WITHIN 4-6 HOURS TO SAVE THE LIMB
This is an EMERGENCY and requires urgent surgery and angioplasty (widening of arteries with balloon)
Intra-arterial thrombolysis
Surgical removal of embolus if present
What is Intermittent claudication
Ischaemic leg pain
Tissue is NOT DYING just SUFFERING
In moderate exercise, you have oxygen debt resulting in a build up of lactic acid resulting in pain
What is critical ischaemia
Tissue is DYING and SUFFERING AT REST
Blood supply is inadequate to allow basal metabolism
No reserve available for the increased demand
Resting pain - typically NOCTURNAL
Gangrene/infection risk
Diagnosis of Severe nocturnal pain in all toes of the left foot only relieved by hanging foot over the edge of bed (using gravity to perfuse)
Critical Ischaemia
Diagnosis of Loss of the use of right side of body and fast irregular pulse
Acute Ischaemia
Diagnosis of Non-healing painful ulcer on big toe with no trauma
Critical Ischaemia
