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