peripheral arterial disease Flashcards
is critical limb ischaemia the same disease process as coronary and carotid atherosclerotic disease?
yes
what are the risk factos for critical limb ischaemia?
Male Age Smoking Hypercholesterolemia Hypertension Diabetes
what is the first stage of critical limb ischaemia?
Asymptomatic, incomplete blood vessel obstruction
what is the second stage of critical limb ischaemia?
Mild claudication pain in limb
Stage IIA: Claudication when walking a distance of greater than 200 meters
Stage IIB: Claudication when walking a distance of less than 200 meters
what is the third stage of critical limb ischaemia?
Rest pain, mostly in the feet
what is the fourthstage of critical limb ischaemia?
Necrosis and/or gangrene of the limb
what type of questions should you ask in a history?
Claudication: Exercise tolerance, effect of incline, change over time, relieved by rest? Where in the leg, type of pain. Bilateral?
Rest pain: Type of pain, relieving factors
Tissue loss: Duration, history of trauma, peripheral sensation
Risk factors Past Medical History Drug History Occupational History – Daily Habits Surgical History
what are signs of chronic ischaemia on the legs?
Ulceration
Pallor
Hair loss
what things would you feel for when examining a patient with chronic ischaemia?
Temperature
Capillary refill time
Peripheral sensation
Pulses – start at the aorta
what examinations would you do for chronic ischaemia?
Ankle Brachial Pressure Index
Buerger’s test
what imaging would you do for a patient with chronic ischaemia?
Duplex
CTA/MRA
Digital subtraction angiography
what is buergers test?
Elevate legs Pallor Buerger’s Angle < 20 degrees severe ischaemia Hang feet over edge of bed Slow to regain colour Dark red colour (hyperaemic sunset foot)
with what other condition should peripheral artery disease be managed with the same way?
coronary artery disease
whats the best medical therapy for peripheral artery disease
Combination of
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
what are the risk factor control for managing peripheral artery disease?
BP control: Target <140/85
Smoking cessation: Excess risk of cardiovascular disease diminishes within 4-6yrs
Diabetic control: 10% of PAD patients are undiagnosed diabetics. Tight glycaemic control prevents microvascular disease
Exercise: 150% improvement in walking time
what open surgery would you fo on a pateint with peripheral artery disease?
Bypass and/or
Endarterectomy
what endovascularintervention would you do on a patient with PAD?
Balloon angioplasty
Stent placement
Atherectomy
what does a surgical bypass require?
inflow
a conduit
outflow
what are complications of 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)
whats an embolus?
a blood clot, air bubble, piece of fatty deposit, or other object which has been carried in the bloodstream to lodge in a vessel and cause an obstruction.
whats a thrombus?
: a blood clot formed in situ within the vascular system of the body and impeding blood flow.
whats the pathophysiology of acute limb ischaemia?
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 6 Ps of clinical presentation of acute limb ischaemia?
Pain Pallor Pulse Deficit Paraesthesia Paresis/Paralysis Poikilothermia (cold) Compare to contralateral limb
what should you consider for the jistroy of a patient with acute limb ischaemia?
Cardiac history Onset/duration of symptoms History of chronic limb ischaemia Risk factors for CLI Functional status
what should you do wjen a patient has an ambolus?
embolectomy
what should you do wjen patient has suspected thrombus in situ
endovascular mechanical thromboectomy/thrombolysis
open embolectomy +/- bypass
what should you do if limb is non salvagable?
amputation or palliate
Pathophysiology of diabetic foot disease?
Microvascular peripheral artery disease Peripheral neuropathy Mechanical imbalance Foot deformity Minor trauma Susceptibility to infection
how would someone prevent diabetic foot ulcers?
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
how do you manage diabetic foot disease/ulcers?
Prevention
Diligent wound care
Infection – consider systemic antibiotics
Investigate for osteomyelitis, gas gangrene, necrotizing fasciitis
how else would you manage diabetic foot disease?
Revascularization – Very distal disease
Attempt distal crural angioplasty / stent
Distal bypass
Amputation
