Peripheral arterial disease Flashcards
What is peripheral arterial disease?
Narrowing of the arteries supplying the limbs + peripheries hence reducing blood supply.
What is the main symptom of peripheral arterial disease?
Claudication - intermittent crampy, aching pain in the leg that occurs on exertion.
What is critical limb ischaemia?
End stage peripheral arterial disease
Inadequate blood supply at rest
How does critical / chronic limb ischaemia present?
6 Ps - Pain Pallor Pulselessness Paralysis Paraesthesia / pins + needlse Perishing cold
Also with ulcers and gangrene
What is the main cause of acute limb ischaemia?
A thrombus (clot) blocks the arterial supply of the distal limb - this may have embolised from elsewhere
What is the difference between necrosis and gangrene?
Both refer to death of tissue, but gangrene is specifically due to inadequate blood supply.
What is ischaemia?
inadequate oxygen to tissue due to reduced blood supply.
What is atherosclerosis?
Thickening + stiffening of arteries due a build up of plaques in the walls (fatty deposits /lipids)
What are some risk factors for atherosclerosis?
Old age Family history Male Smoking High alcohol intake Poor diet - high in sugar + trans fats Sedentary lifestyle Obesity Stress
What are some complications of atherosclerosis?
Angina MI (heart attack) TIA stroke Peripheral arterial disease Chronic mesenteric ischaemia
What is Leriche Syndrome and how does it present?
Occlusion of the distal aorta / proximal common iliac artery. Presents with - thigh/buttock claudication - absent femoral pulses - male impotence
What are some signs of arterial disease on inspection?
Skin pallor Cyanosis Muscle wasting Hair loss Ulcers Poor wound healing Gangrene
What may be seen on examination in arterial disease?
Reduced skin temperature Reduced sensation (parasthesia) Prolonged capilliary refill (> 2 seconds)
What causes arterial ulcers?
Ischaemia secondary to an inadequate blood supply
What causes venous ulcers?
Impaired drainage and pooling of blood
What investigations are used for diagnosing peripheral arterial disease?
Bloods - serum lactate to assess level of ischaemia
Ankle-brachial pressure index
Duplex ultrasound - shows the speed and volume of blood flow
Angiography (CT or MRI) - using contrast
What is ankle brachial pressure index and what do the results indicate?
A ratio of systolic blood pressure in the ankle compared to the arm.
0.9 - 1.3 is normal
0.6 - 0.9 - mild peripheral arterial disease
0.3 - 0.6 - moderate - severe peripheral arterial disease
Less than 0.3 - severe disease and critical ischaemia
What are the management options for intermittent claudication?
Lifestyle changes - e.g. stop smoking, control diabetes
Exercise training
Medical treatments - atorvastatin, clopidogrel and naftidrofurly oxalate (acts as a peripheral vasodilator)
Surgery
What are the surgical options for managing intermittent claudication?
Endovascular angioplasty + stenting
Endardectomy - cutting vessel open + removing atherosclerotic plaque
Bypass surgery
What is the management for critical limb ischaemia?
Endovascular angioplasty + stenting
Endardectomy
Bypass surgery
Amputation
How is acute limb ischaemia managed?
Heparin (bolus then infusion - even if before surgery) Endovascular thrombolysis Endovascular thrombectomy Surgical thrombectomy Endardectomy Bypass surgery Amputation
What is the long term management after acute limb ischaemia?
Reduction of CVD risk
- regular exercise
- smoking cessation
- weight loss
Anti platelet therapy - low dose aspirin or clopidogrel
If amputated will need physio + long term rehab plan
What are the complications of acute limb ischaemia?
Mortality rate - around 20%
Reperfusion injury –> compartment syndrome and electrolyte imbalances
Amputation / loss of limb (and complications of this surgery)
What are risk factors for chronic / critical limb ischaemia?
Smoking Diabetes mellitus Hypertension Hyperlipidaemia Increasing age Family history Obesity Physical inactivity
What specific test can be use to test for critical limb ischaemia?
Buerger’s test
involves lying the patient down and raising their legs until the go pale. Then lower them down until the colour comes back. The angle at which the limb goes pale is Buerger’s angle (less than 20 indicates severe ischaemia)
What are the complications of critical / chronic limb ischaemia?
Sepsis (infected gangrene) Acute on chronic ischaemia Amputation Reduced mobility + quality of life. 5 year mortality is around 50%
