CR - Peripheral Arterial Disease (i)
intro
progressive
influenced by genetic+environmental factors
leads to atherosclerotic disease + decreased oxygenated blood supply to limbs
Classification
occlusive disorders
aneurysmal disorders
vasculitic disease
acute or chronic (most common)
predominantly of lower limbs
typical vasc patient
IHD
elderly
male
smoker
hypertension
hyperlipidaemia
diabetic
often self-inflicted
pathophysiology: vasc damage -> narrowing -> decreased perfusion (art insufficiency) -> signs + symptoms of ischaemia
Signs + symptoms of occlusive art disease
intermittent claudication
most common
non-musculoskeletal pain
brought on by walking (increased O2 requirements, no pain for first few steps, worse when fast or uphill)
relieved by rest (standing for 1-3 mins, no need to sit/lie down)
progresses over time (able to walk shorter + shorter distances)
rest pain
when ischaemia becomes critical
in sole of foot @ night
wakes patient
relieved by hanging their foot over side of bed
tissue loss
gangrene
ulceration
peripheral pallor + hair loss
if acute
sharp severe pain
sudden coldness of limb
must Tx in 6 hrs or limb will no longer be viable (amputation only option @ this stage)
painful
variable size
breach in epithelium with "punched out edges"
usually on lat malleolus
begins with small trauma - can't heal due to poor blood supply
exacerbated by diabetic neuropathy
dry - coag necrosis - no infection
wet - liquefactive necrosis - infection - surrounding erythema + cellulitis
factors influencing management decisions
nature of symptoms (critical vs non-critical)
general health
social circumstances - impact on independence of QOL
investigations
Hx + exam
bloods
fasting lipids
fasting glucose
HbA1c
vasc studies (ABI)
non-invasive doppler assessment
sys BP @ ankle / sys BP @ arm
venous duplex study
specific + sensitive for Dx, predicting mortality + adverse CV events
over 0.9 = normal
0.5-0.9 = mild/moderate (intermittent claudication)
under 0.5 = severe (rest pain)
angiogram
medical management
lifestyle changes
smoking cessation
diet
diabetic control
weightloss
exercise
supervised exercise walking programme = v effective (promotes muscle hypertrophy + collateralisation/neovascularisation)
antihypertensives
antiplatelets (aspirin)
statins
anti-inflamm
increased perfusion
phosphodiesterase type 3 inhibitor (cilostazol)
increases cAMP -> smooth muscle relaxation, vasodilation, inhibition of platelet aggregation
increases perfusion
decreases risk of CV event
surgical management
endovascular
percut angioplasty
reconstructive vasc surgery (open)
balloon to open chronically narrowed art
stents
min invasive but not as durable
e.g. femoropopliteal bypass
graft made from prosthetic material or patient's own vein
amputation
usually patient is sicker + older, hence 50% die in 3 yrs
not all walk after
only half get prosthetic limb (85% of these people walking in 1 yr)
39% totally wheelchair bound @ 5 yrs
make level as distal as possible in the interest of mobility
social reintegration NB
live-saving (necessary to prevent sepsis) but huge effect on QOL