Arterial diseases of the limbs Flashcards
What is the clinical presentation of arterial occlusive disease?
Cold, loss of pallor, painful leg.
What is the clinical presentation and progression of venous disorders?
What are the surgical interventions available for the treatment of arterial occlusive disease?
Stents or bypass
What does aorta divide into?
Aorta - illiac - common femoral (-cprofunda femoris) - Superficial femoral artery - popliteal artery - (ant tib - dorsalis pedalis) (Peroneal artery) (Posterior tibial artery)
How to feel aortic pulse?
2 hands above umbillicus
Check now you can feel common femoral, popliteal and posterior tibial and dorsalis pedilais
hip crease, under knee (relaxed knee), inside of inside ankle, on foot
What is Chronic Limb Ischemia?
Long term atherosclerotic disease in leg arteries, causing claudication or some form of ischemia eg on excertion
What are the risk factors for CLI?
Male Age Smoking Hypercholesterolemia Hypertension Diabetes
What are the 4 stages of CLI (Fontaine classification)
Stage I - No symptoms, incomplete blood vessel occlusion
II = IIa Claudication on walking over 200m, IIb claudication on walking under 200m
III = at rest pain in feet
IV = Gangrene/necreosis
Which stages are critical limb ischemia?
Stage III and IV (rest pain and gangrene/necrosis)
What is claudicaition?
Cramping/gripping sensation in calfves caused by ischemia
What factors should you ask about claudcation?
When, how long, exact location, exacerbating/relievling factors, bilateral, exercise tolerance, pain type.
Also think about Risk factors Past Medical History Drug History Occupational History – Daily Habits Surgical History
What are claudication relieving factors?
Dangling feet off bed
What foot symptoms are signs of chronic limb ischemia? Do you need to look at both legs?
Yes need to look at both legs to compare. Think UPH- Chonic limb ischemia!
Ulceration
Pallor
Hair loss
What is the hand held doppler used for?
To auscultate the dorsalis pedis and posterior tibial pulses
What do you need to feel for in clinical exam before the doppler exam?
Temperature
Capillary refill time
Peripheral sensation
Pulses – start at the aorta
What is ABPI?
Arterial Brachial Pressure Index:
Ankle Pressure (mmHg) / Brachial Pressure (mmHg)
A good measurement for the amount of occlusion of the arteries.
WHat is a healthy ABPI?
greater than 1
ABPI critical limb ischemia
Under 0.5
intermittent claudication abpi
0.5-0.95
Gangrene and ulceration abpi
less than 0.2
What is Beurger’s test?
You lift the legs and thne put them back down, if has limb ischemi, then blood flow retunr will be slow and will turn darker colours
Why does foot go to dark red colour?
Because it is chronic limb ischemia. usually in healthy leg approx only 1/3 capillaries etc are dilated, but due to hypoxia, all vessels are dilated.
What investigations can be used for CLI? Pros and cons
Duplex - no contrast or radiation required, produces dynamic image. Not good on abdomen, operator dependant and time consuming.
MRACTA - clearer, requires ratiation/contrast and can overestimate calcification/difficult in low flow states
What is first line invesitgation according to NICE?
CTA/MRA
What usually follows a digital subtraction angiography?
Angioplasty (stent)
Wgat is angioplasty?
Stent
What is best medical therapy for Chronic Limb Ishemia?
combination of antiplatelet and statin
Antiplatelet: Reduces risk of requiring revascularization as well as cardiovascular and all-cause mortality
Statin: Inhibits platelet activation and thrombosis, endothelial and inflammation activation, plaque rupture by lowering LDL cholesterol in blood.
How can we control risk factors in CLI?
Stop smoking, increasing walking 150%, controlling diabetes (10% peeps are unknown diabetes), managing bp (ideally 140/85)
What are the 2 options for revasularisation
Endovascular intervention (balloon angioplasty/stent/atherectomy) and open surgery (bypass/endarterectomy)
What is required for a surgical bypass?
In and out flows and something to put in the middle (ocnduit) eg synthetic or vein
Give examples of General and Technical risks of complications arising from surgical bypass
General : Bleeding, wound infection, pain, scar, DVT, PE, MI, CVA, LRTI, death (2%)
Technical :Damage to nearby vein, artery, nerve, distal emboli, graft failure (stenosis, occlusion)
Which options are better short/long term?
Short term endothelial (stent) long term is bypass
What is acute limb ischemia? And causes?
Medical emergency - usually as a result of throbus or embolism. Severe limb ischemia, limb will die within 6-8h.
Pathophysiology:Arterial embolus: MI, AF, proximal atherosclerosis (NOT DVT/PE)
Thrombosis: Usually thrombosis of a previously diseased artery.
Trauma
Dissection
Acute aneurysm thrombosis i.e. popliteal
What are the 6Ps of acute limb ischemia? What do you have to compare?
Pain Pallor Pulse deficit Poikilothermia (cold) Paralysis/Paresis (muscular weakness) Paraethesia (abnormal sensatino eg pins and needles)
What is compartmet symdrome?
When an area is shut off for more than 6-8 hours, swelling, blocks weins, tender calf, Creatinine kinase increase, increased risk of renal failure.
Muscle ischaemia (irreversible after 6-8 hours)
Inflammation, oedema, venous obstruction
Tense, tender calf
Rise in creatinine kinase
Risk of renal failure (myoglobulinaemia)
What are the 3 stages of acut limb ischemia?
I - Viable (audible art and venous doppler)
II - Threatened (inaudible art doppler, audible venous)
III - Irreversiable (inaudible art and venous doppler)
Treatment options:
Salvagable limb - ebulus? Thrombus?
Non-Salvagable? Fit/willing for amputation?
Salavagavgle : Embolus - embolectomy Thrombus - consider endovascular (thrombectomy/thrombolysis) or open embolectomy (w/wo bypass) Non salvageable: Fit/willing for amputation - amputation Not - palliate
What % ALI embolic/thrombotic?
30% embolic, 60% thrombosis
How long does it take for irreversiable muscle ischemia?
6-8h
Is ALI a medical emergency?
Yes
What is Diabetic foot disease? How prevelent? What % require amputation?
Ulcers on foot as result of diabetes. 25% all diabetics will get ulcers, 50% become infected, 20% require amputation
What are the major contributing factor to ulcers? How best to prevent?
Microvascular peripheral artery disease Peripheral neuropathy Mechanical imbalance Foot deformity Minor trauma Susceptibility to infection
Prevent:
Always wear shoes – avoid minor injuries
Check fit of footwear
Check pressure points/plantar surface of foot regularly
Prompt and regular wound care of skin breaches
Effective glycaemic control
Management of diabetic foot disease?
Antibiotics asap Maggots (larvae therapy) Negative pressure (shown to be best) skin grafts dressings Amputation/revascularisation
Where are 2 major sites of amputation?
Above and below the knee
