Peripheral Vasculature in Health and Disease 1, Arterial Aspects Flashcards
What are the relative sizes of artery diameter?
Large vessels- aorta, great vessels in chest, iliac
Medium- mesenteric, renal, femoral, popliteal, tibial, subclavian, brachial, radial
Small- blood vessels in the hand and foot, the kidneys, the brain, the eye
How does blood reach the peripheries by several routes?
Arteries have many anastomoses
Blood can reach target organs by several routes
Collateral circulation can compensate for occlusion of the main system in some circumstances
Describe the starling forces across the capillary bed
Blood pressure (35 mmHg) Osmotic (25 mmHg) -Arteriole- Blood pressure (16 mmHg) Osmotic (25 mmHg) -Venule-
What is the arterial pathology when dilated?
Aneurysm
What is the arterial pathology when narrowed?
Stenosis
What is the arterial pathology when blocked?
Occluded
What is the arterial pathology when split?
Dissection
What is the arterial pathology when over sensitive?
Vasospasm
What is the arterial pathology when inflamed?
Vasculitis
Describe aneurysms
Definition= 1.5 x the normal diameter
Degenerative aneurysms most common
Inflammatory, mycotic (infective), traumatic can also occur
Connective tissue disease- Marfans, Loeys-Dietz
How can aneurysms be detected?
CT Angiogram imaging
How can aneurysms be repaired?
Open surgery
Endovascular repair
Describe stenosis
Atherosclerosis
20% of UK population aged 55-75 have peripheral arterial disease
5% have symptoms
Cardiovascular risk HIGH
Describe atherosclerosis
Lipid deposits
Cholesterol rich plaque
Calcification
Plaque rupture= occlusion
What are the symptoms of stenosis
Claudication
Short distance Claudication
Nocturnal pain/ rest pain
What is Claudication?
Pain on walking a fixed distance
Worse uphill
Eases rapidly when you stop
Angina of the leg
What is the treatment for claudication?
Stop smoking
Aspirin
Lipitor tablets
What are the symptoms of acute occlusion?
The 6 P’s
- Pain (sudden onset)
- Pallor
- Perishing cold
- Paraesthesia
- Pulselessness
- Paralysis
What are the symptoms of chronic occlusion?
- Short distance claudication
- Nocturnal pain
- Pain at rest
- Numbness
- Tissue necrosis
- Gangrene
What is the treatment for occlusion?
Stent
Amputation
Describe amputation
- Median survival after amputation is 2.25 years
- 30 day mortality of 17%
- 30% lose the other leg with 2 years
- 6000 per year in UK
Describe vasospasm
- Over active vasoconstriction
- Capillary beds shut down
- Triggers- cold, stress
- Can have underlying connective tissue disease
Describe vasculitis of large vessels
Takayasu’s disease- “pulseless disease”
Describe vasculitis of medium vessels
Giant Cell Arteritis/ Polymyalgia
Describe vasculitis of small vessels
Lots of polyangiitis conditions usually involving the kidneys
What is the treatment for vasculitis?
Steroids
Other immunosuppressive agents
How are broken arteries caused?
Trauma
Self-inflicted
Iatrogenic ( illness caused by medical examination or treatment)
What does IV Drug abuse cause?
Arterial pseudoaneurysm
collection of blood that forms between the two outer layers of an artery, the tunica media and the tunica adventitia. It is usually caused by a penetrating injury to the vessel, which then bleeds, but forms a space between the above two layers, rather than exiting the vessel.
Describe the link between Diabetes and Arterial disease
- Major problem for healthcare systems worldwide
- Increasing incidence
- Diabetic patients are 20 times more likely to have an amputation
Describe Diabetic Foot
-Neuropathic (disease or dysfunction of one or more peripheral nerves, typically causing numbness or weakness)
-Ischaemic
-Infected
-Calcified vessels
-Small vessel arterial disease
Patients can’t see their feet (retinopathy)
Describe Charcot Foot
- End-stage diabetic foot changes
- Neuropathic
- Warm (greater than 2 degrees than normal, AV shunting)
- Multiple fractures
- “Rocker bottom” sole (midfoot collapse)
