Prof Walsh´s notes Flashcards
What is an Ankle Brachial pressure index?
simple measure to determine if the patient has peripheral arterial disease.
needs to take measurements manually using a doppler probe of suitable frequency in preference to an automated system.
Where do you place the BP cuff in checking ABPI?
placed just above the malleoli using cling film to protect the patient from the cuff
What pulse are you locating with the doppler with ABPI?
dorsal is pedis pulse.
How do you locate the dorsal is pedis pulse?
lateral to the extensor hallucis longus tendon
At which point do you take the pressure reading using the doppler probe?
first inflate the cuff until the artery is compressed (signal drops) and then slowly deflate the cuff until the signal reappears on doppler.
Do you just use the pedis pulse for the ABPI?
locate the posterior tibial pulse (posterior and inferior to the medial malleolus) and do the same protocol
so you have taken the pressure readings from the lower limb what do you need to do next?
need to take the blood pressure from the arm on the same side to the readings.
where is the brachial pulse located?
Locate the brachial pulse in the antecubital fossa medial to the biceps tendon.
How do you calculate the ABPI?
ABPI= highest ankle systolic pressure (the highest of the PT or DP value for that leg) divided by the brachial systolic pressure.
How do you interprete an ABI
less than 0.9 indicates PVD
normal is between 0.9 to 1.3
greater than 1.3 indicates calcified stiff vessels (toe pressures)
What is the definition of an ulcer?
is a discontinuity in the epithelial surface.
how common are leg ulcers?
1% in the greater than 70
if a patient has an ulcer how likely is it to come back ?
1:3 within a year
when looking at an ulcer what is your differential most common to least common?
Venous (70%)
neuropathic
arterial
neoplastic
What are the causes of venison ulcers
superficial or deep venous insufficiency
What is the underlying pathology of venous ulcers?
varicose veins
prev DVT
May turner syndrome
non thrombotic iliac venous lesions
What are the causes of arterial ulcers
large or small vessel disease
What is the other name for small vascular disease?
vasculitis
what is the pathology of arterial disease? most common to least common
atherosclerosis
burgers disease
rheumatoid arthritis
polyarteritis nodosa
what are the two types of traumatic ulcers?
neuropathic (DM, chronic cord compression, alcohol)
others- pressure ulcers
accidental injury
Infective ulcers what is the underlying cause?
malnutrition
what are the causative organisms for infective ulcers?
Strep pyrogenes
(staph aureus)
tertiary syphillis rare
two types of neoplastic ulcers
primary or secondary
What are the most common types of neoplasms primary
squamous cell
basal cell
melanoma
What is the type of ca causes a secondary (ulcerated nodule)
adenocarinoma (primary lung or bowel met)
What is the definition of peripheral arterial disease?
narrowing or occlusion of the arteries to the legs, extracranial arteries to the brain, the abdominal viscera and the arms, most commonly die to atherosclerosis.
What is the prevalence of PVD
10-20% of men greater than 50%
How does PDV present?
most of the time it is asymptomatic (90%)
intermittent leg claudication
critical limb ischemia
What are the risk factors for PVD?
pathological processes that effect the large and small vessel circulation... 1. smoking 2. diabetes 3. long term haemodialysis 4, prev hx of PVD high cholesterol hypertension family history (minor)
What are the clinical features of asymptomatic PAD?
they have no pain (claudication) or tissue loss (ulcers)
They have the risk factors
They have had this before
they may have some physical signs (temp, hypertrophic nail beds, pallor when lifting the leg (buerger’s test)
hair loss
absent pulse
If you can feel the pulses would you go for an ABI?
no because if you can feel he pulses they are unlikely to have asymptotic PAD.
How do you manage asymptomatic PAD?
address the modifiable risk factors: SMOKING, optimise DM control, start an antiplatelet agent aspirin, start a statin
check for any other cause: AAA aortic US
What is the Wilson’s criteria for screening?
- the condition should be an important health problem
- natural history understood
- recognizable early or latent stage
- test that is easy to preform and interpret, acceptable, accurate, reliable, sensitive and specific
- should be treatment
- there should be a policy
- the diagnosis and treatment should be cost effective
- case finding should be a continuous process.
Using the wilson criteria discuss why carotid artery screening would not be a great screening tool.
condition should be an important health problem (carotid artery stenosis can be the source of emboli for stroke), but only 1% general population has significant carotid artery narrowing and only 10% people with stroke have carotid artery stenosis) so it is not cost effective
natural history of the condition is understood (RF plaque formation leading to turbulent flow)
recognisable early or latent stage (not really 90% asymptomatic)
test is easy to preform with carotid US it is non invasive, but it is known to have false positives
the treatment for carotid artery stenosis is angioplasty or carotid endarterectomy this is a procedure that carries a significant amount fo risk (as these procedures can precipitate emboli formation and cause stroke in a plaque that may have otherwise been asymptomatic).
23 strokes prevented and 10 MI induced. Also asymptomatic PVD is not an indication for intervention!!!! So this as a screening tool is not cost effective, and indeed may cause harm.
what is the definition of intermittent claudication?
pain in a muscle group that is brought on my exercise and relieved by rest.
What are some key features of claudication that differentiate it with other causes of leg pain?
pain is felt in the muscle
cramp like
comes on invariably and only with exercise
is always relived by rest for a couple of minutes.
What are the risk factors of claudication?
hypercholestroliema diabetes smoking hypertension previous history of PVD, IHD, or CVD previous lower limb revascularisation
What are the physical signs you might illicit in claudication?
inspection: hair loss, hypertrophic nails
palpation: cold peripheries (gradient)
absent pulses
How do you diagnosis claudication?
positive history and ABI less than 0.9
What is the most important question to ask a patient that will guide your management for intermittent claudication?
can you walk greater than 100 meters without pain.
How do you manage claudication?
- risk factor modification: stop smoking, D.M control, start aspirin, start statin, scan to rule out other cause AAA
- don’t screen for carotid artery disease unless symptomatic
- symptoms- supervised exercise program physiotherapy
- education about foot care wear shoes don’t walk barefoot on the beach….
- no need for imaging because no intervention if can walk greater than 100 meters,
- if the patient cannot walk more than 100 meters, then imaging of the arterial tree (duplex US or angiography)
- counselling of the risk and benefits and durability of intervention.
What defines being symptomatic for carotid artery stenosis?
emboli- amaurosis fugax, transient ischeamic attacks, ischemic stroke (on the same side of the lesion)
what is the prognosis of IC
half will spontaneously resolve (stop smoking!!!) 25% require intervention 5-10% CLI 2% limb amputation 30% dead within 5 years from CVD
What is the definition of critical limb ischaemia?
rest pain requiring opiates and or tissue loss due to reduced arterial perfusion of the limb.
What are the clinical features of critical limb ischaemia?
must have REST pain or TISSUE LOSS or BOTH in the presence of ABI less than 0.9 or an unreliable ABI (greater than 1.3)
What are the classical features of rest pain?
location- felt across the base of the toes
variation- worse at night, relieved by hanging the leg out of the bed or sleeping in a chair.
walking helps
pain is refractory to strong analgesics (opioids)
plus or minus claudication history.
Is night cramps a feature of CLI?
no this is normally of venous origin
What are the risk factors for CLI?
artersclerotic RF- DM, hypercholesterolemia, hypertension, smoking
previous history- IHD, valvular heart disease, CVD
lower limb revascularisation
What are some signs of CLI
inspection: loss of hair, ulceration (pressure points) 1st metatarsal between the toes, pallor, hypertrophic nail changes, oedema
palpation= perishingly cold peripheries, absent pulses
lower limb neuro- paralysis, pain
What is the annual mortality for critical limb ischemia?
20%
management of CLI
modificable risk factors- smoking!, D.M control, start a statin
start an antiplatelet aspirin
scan to rule out AAA
if they are fit for intervention (endovascular or open surgery) vs amputation. if fit for intervention then will need endovascular imaging (Duplex US, angiography)
A 45 year old male comes into your practice complaining of intermittent leg claudication, muscle pain relieved by rest brought on by exercise. He can walk a about 500 meters before he gets the pain… what is your management?
- establish cause ABI
- check for other cause- AAA
- secondary prevention- modifiable risk factos and optimisation and aspirin
- start graduated exercise plan
- NO OTHER imaging
- follow up in clinic by assessing pain free walking distance.
What are pretty much always dealt with by endovascular means?
short length stenosis or occlusions of the iliac or femoral arteries
what is the length of a long occlusion?
greater than 15 cm
what are long occlusions or long stretches of intermittent stenosis best treated by?
bypass grafting
What is the aim of the procedure
to restore in line flow from the aorta to the toes
Woudl you rather be a patient with a endovascular repair of the proximal leg or the distal leg?
proximal success rates go down the more distal you go.
when is lower limb angioplasty used?
for the iliac and the superficial artery lesion
can be used for tibial but less successful
What is the the procedure protocol for a LL angioplasty?
- numb the area- local anaesthetic
- common femoral punctured with a needle wire passed through the occlusion or stenosis and the inflatable balloon is positioned. The balloon is inflated to reopen the artery.
- stenting not great evidence but can be used in iliac lesions cochrane review but no benefit with SFA
What are the complications of lower limb angioplasty? You are consenting the patient
access point complications: bleeding occlusion, pseudo aneurysm formation.
distal arterial compilations: arterial dissection, embolsation of debris down run of vessels, thrombosis of angioplasty site- acute limb ischemia and limb loss
systemic complications: MI, contrast induced kidney injury, CVD, death
The patient consents to a LL angiography. What is your consultant going to ask you to organise?
- keep the patient fasting nil by mouth (6 hours food, 2 hours clear fluids)
- FBC (platelets, infection anaemia), liver function test, Urea and electrolyte (baseline remember contrast- creatinine), clotting profile
- hold the anticoagulants (Noah, heparin, warfarin)
- aspirin continued
- give usual meds
- consider pre procedure fluids if diabetic or baseline eGFR less than 60
- post procedure bed rest 6 hours
- watch for complications: ischemia, bleeding
Post procedure LL angiography. What are you going to be watching out for when you are rounding?
complications: ischemic limb, bleeding, EWS drop in blood pressure in the first 24 hours bleeding until proven otherwise)
illiac fossa palpation for bleeding
pain management
infection at the wound site
IV fluids 24 hours
creatinine at 24 and 48 hours
creatinine rising in comparison to the baseline patient needs to be monitored (AKI)
When would you consider lower limb surgical revascularisation?
If there is a tight blockage of the common femoral (not being able to allow a balloon catheter through) endartectomy
long occlusions and multilevel stenosis - bypass graft
When can bypass grafting be an option?
needs to identify a named target vessel which runs to the foot.
aorta to femoral (illiac)
femoral to popliteal (SFA)
femoral- distal (below the knee blocks)
What types of grafts are used?
vein or artificial grafts
below the knee vein grafts work better
but above knee no diff,
A patient is being consented about the lower limb revscularisation… what do you need to warn him about?
procedure specific- bleeding bypass occlusion distal embolisation pseduoaneurysm formation bypass anastomoses graft infection anastomic stenosis nerve injury limb loss wound infection (groin) seroma formation and lymph leak general: MI (1:100) DVT or PE (1:100) death (1:50)
You are prepping a patient for revascularisation surgery, what do you need to do?
- nil by mouth and fasting
- FBC, U&E, clotting
- cross match *4 u aorta-bifem 2 for others)
- recent chest X ray (6 months) and CV exam
- limb marked and double check that it is the effected limb
- hold anticoagulation, continue aspirin
- give usual meds
You are on the post op ward round, you see a patient who has just undergone revascularisation surgery… what are you looking for
- general inspection- shock
- complications- foot ischaemia
- LMWH
- taking bloods FBC, U&E 24 and 48 hours
- check output
- don’t repeatedly disturb dressings- use transparent dressing or check when concern for infection
- early mobilisation
- check belles
urinary catheter removed at 24 hours - check coag and FBC before removing epidural catheter
- small degree of leg swelling is expected,
