Limb Problems Flashcards
What are two complications of renal atherosclerosis?
-Hypertensive nephropathy (longstanding hypertension chronically deprives kidneys of blood flow, leading to decline in kidney function)
-Hypertension resistant to medical management (renal artery stenosis causes hypertension as kidney’s response to insufficient blood flow is to regulate systemic BP higher)
What are four complications of cerebrovascular atherosclerosis?
-TIAs
-Strokes
-Amaurosis fugax (a transient unilateral loss of vision due to emboli passing into ophthalmic artery)
-Drop attacks (sudden episodes of dizziness or syncope)
What are four complications of lower limb artery atherosclerosis (peripheral arterial disease)?
-Intermittent claudication (calf pain on walking caused by stenosis or occlusion to artery supplying the calf or thigh)
-Gangrene (necrosis of skin or whole digit of foot due to poor arterial supply)
-Arterial foot ulcer (break in skin due to arterial supply poor enough that skin integrity is not maintained)
-Ischaemic rest pain (pain in limb at rest due to insufficient arterial supply to perfume the limb even without exertion)
How does gangrene appear?
Black, dry and sometimes shrivelled.
What does the term ‘tissue loss’ refer to?
The clinical entities of gangrene and ulcers.
When is ischaemic rest pain classically worse?
At night, due to removal of effect of gravity when the lower limb is raised in bed.
What are three complications of mesenteric artery atherosclerosis?
-Post-prandial abdominal pain (severe pain after eating due to occlusion of arteries supplying the bowel)
-Weight loss (patient sometimes avoids food for fear of precipitating pain)
-Acute abdominal pain (sudden occlusion to blood supply of bowel can cause bowel ischaemia and pain)
How is acute abdominal pain due to bowel ischaemia characterised?
Central, constant abdominal pain sometimes associated with nausea or vomiting, and/or loose stools.
What are the three main types of ulceration in the leg and foot?
-Venous
-Arterial
-Neuropathic
What is meant by the ‘gaiter’ of the leg?
The area around the malleoli and lower calf
What are three signs of chronic venous insufficiency?
-Venous ulcers
-Varicose veins
-Thickened skin
Describe the varying depths of different types of ulcers.
Venous - shallow
Arterial - deep
Neuropathic - deep
What colours are the different types of ulcers?
Venous - pink
Arterial - pale/yellow/black
Neuropathic - pink
Which type of ulcer is classically largest?
Venous ulcers
Which region of the lower limb are each type of ulcer classically found?
Venous - gaiter area
Arterial - forefoot/toes
Neuropathic - plantar foot
Which type of ulcer does an examination finding of ‘sunset foot’ indicate?
Arterial
Which type of ulcer does an examination finding of abnormal foot shape indicate?
Neuropathic (abnormal foot shape due to diabetic neuropathy)
What other visible features can be seen on examination of a lower limb with venous ulceration? (2)
Varicose veins
Skin changes of chronic venous insufficiency
In which type of ulcer may pedal pulses be absent?
Arterial ulcers
What are the classical risk factors for venous ulcers? (3)
-Previous DVT
-Previous limb fracture
-Previous varicose vein surgery
When does Chronic Limb Threatening Ischaemia (CLTI) occur?
When arterial limb supply to lower limb is insufficient even when muscles are resting, causing skin breaks (i.e ulceration) and ischaemic rest pain.
What are the two venous systems that drain the lower limb?
Superficial - drains skin and subcutaneous tissues
Deep - drains muscles
What are ‘perforators’?
Connections between the superficial and deep venous systems
What does the term ‘chronic venous insufficiency’ describe?
The condition that results from inadequate venous drainage from the lower limb.
What changes in appearance of a limb may be related to chronic venous insufficiency? (6)
-Brown skin (due to haemosiderin deposition within the skin)
-Erythema
-Ulceration (skin weakened by pooling of fluid within it due to poor venous drainage)
-Oedema
-Rash (venous or varicose eczema)
-Thickened skin (lipodermatosclerosis - reaction to chronic oedema and inflammation)
What symptoms may arise from chronic venous insufficiency? (6)
-Night cramps
-Restless legs
-Pain in lower limb (can be specific to varicose veins themselves if present)
-Itching
-Aching (worsening throughout the day due to spending longer upright)
-Heaviness (may also be described as a ‘dragging’ feeling)
What is venous claudication?
Pain in the calf/foot after walking a good distance, associated with swelling.
Why is the muscle most likely to suffer from intermittent claudication the calf? (2)
-Peripheral arterial disease is common in the femoral-popliteal vessels responsible for delivering blood to that part of the leg.
-The calf muscle also works very hard during exercise, and therefore suffers most from poor arterial supply.
Where may intermittent claudication pain be felt in patients with disease of the iliac arteries?
In the gluteal muscles, causing buttock pain
What is ‘sunset foot’?
Vasodilation of the superficial blood vessels in patients with chronic limb threatening ischaemia, causing erythema of the forefoot/toes that resolves on raising the foot.
What is Ankle-Brachial Pressure Index (ABPI)?
The ratio of systolic blood pressure at the ankle to that in the arm, indicating vessel competency.
How is Anke-Brachial Pressure Index (ABPI) performed? (4)
-Hand held Doppler used to auscultate the arterial waveform in the brachial artery.
-BP cuff inflated until signal disappears; pressure at which this happens is recorded (this is systolic pressure).
-Same manoeuvre performed in leg, with Doppler auscultating posterior tibial and/or dorsalis pedis artery; pressure at which signal disappears is again recorded.
-Two pressures are compared as a ratio.
How are Ankle-Brachial Pressure Index (ABPI) results interpreted? (3)
—>A ratio of 1 indicates a normal result - blood flow in the leg is the same as that to the arm.
—>Ratio < 0.8 - patient may suffer with intermittent claudication, or have no symptoms.
—>Ratio < 0.4 - blood flow may be so restricted that patient has pain at rest and/or at night, and tissue loss in foot = suggestive of chronic limb threatening ischaemia
Why can Ankle-Brachial Pressure Index (ABPI) readings be more difficult to obtain accurately in diabetic patients?
The walls of the arteries in these patients are more likely to be calcified, making them less able to be compressed using a blood pressure cuff.
How is peripheral arterial disease managed (NICE guidelines)? (2)
-Offer patient information, advice, support and treatment regarding secondary prevention of cardiovascular disease (lifestyle changes, statins and anti-platelet medications)
-Prevention, diagnosis and management of diabetes and hypertension
What are the management options for intermittent claudication? (4)
-Supervised exercise programme
-Angioplasty and stenting (when above doesn’t work and imaging confirms suitability)
-Bypass surgery and graft types (in severe, lifestyle-limiting cases when above unsuccessful/unsuitable)
-Naftidrofuryl oxalate (only when patient refuses surgery)
What is Naftidrofuryl oxalate?
A peripheral vasodilator used to treat peripheral and cerebral vascular disease.
What is involved in an angioplasty of the superficial femoral artery? (3)
-Needle used to puncture common femoral artery at level of the groin.
-Contrast injected into artery to visualise the stenosis or occlusion.
-Wire passed through the diseased artery and a balloon is passed over the wire; this is inflated in the diseased segment to widen the channel of flow.
What are the red flag symptoms requiring urgent referral to hospital for unilateral limb pain? (4)
-Rest pain/night pain in forefoot or toes
-Tissue loss (gangrene or ulceration)
-Sensorimotor deficit
-Acute swelling
