L25/26: Vascular Surgery And Peripheral Arterial Disease And Ulcers Flashcards
What are the layers of the arterial wall
Tunia intima
Tunica media
Tunica externa
What is the tunica intima made of
Endothelium
What is the tunica media made of
Smooth muscle
Elastic fibres- internal and external
What is peripheral arterial disease
Obstruction of large arteries of the systemic vascular system
What is a atherosclerosis
Build up plaque formation which leads to the narrowing of the vessel lumen wall and ischaemia distal to the atheroma
What are the modifiable risk to peripheral arterial disease
Smoking Blood sugar Hyperlipidemia Hypertension Obesity
What are the non modifiable risk factors for peripheral arterial disease
Age
Geneder
Family history
Genetic
What are the 3 types of ischaemia that can occur in the limb
Acute limb ischaemia
Chronic limb ischaemia
Critical limb ischaemia
What is acute limb ischaemia
When you suddenly develop a sudden decrease in limb perfusion producing new or worsening symptoms
What is chronic limb ischaemia
Gradual worsening of limb pina bough on by exercise and relieved by rest
What is critical limb ischaemia
Rest pain and circulation is badly impaired that there is a risk for limb loss
What can acute limb ischaemia be due to
Thombus- you already have a thrombus and something occludes it
Embolus
Trauma- crush injury can block the vessel
Transection- transaction of an artey will cut off the blood flow
Dissection: space opening up betwwen the layers of the blood vessel
What should you look at in the history of someone with acute limb ischaemia
Atrial fibrillation
Athersclerosis
How does acute limb ischaemia present
6 ps: Pulseless Pain Pallor Polar (cold) Paralysis Paraesthesia
What is the management of acute limb ischaemia
Analgesia
Aspirin- to reduce the clotting in the blood
Anti-coagulation- breakdown the clot that has already formed
Thrombolysis: break down the clot
What is the surgical management of acute limb ischaemia
Embolectomy- open the vessel and remove the embolus
Bypass surgery- long segment of a clot you will bypass it by diverting the blood flow
Amputation
What can occur if you get the blood flowing back as a complication
Reprefusion injury
What is reperfusion injury
This is when you re introduce blood flow to the tissue that is being infarcted has a sudden relase of toxic compounds associated with tissue death
What does the release of toxic compounds cause
Vasodilation- this leads to shock (not enough blood flowing round the system)
Permeable vessels: more tissue fluid and white blood cells pass into the infected area - you can develop acute respiratory distress syndrome
Renal failure: brocken down tissue relases myoglobulin which sits at the glomerular basement membrane and blocks the kidney
What is another complication fo re introducing blood flow
Compartment syndrome
How does compartment syndrome occur
Vessels become more leaky
You increase the pressure due to lots of fluid which leads to raised intra compartment pressure
The pressure will obstruct the venous outflow from the limb and the arterial blood flow can become cut off
This leads to secondary limb ischaemia
What is the treatment of compartment syndrome
Fasciostomy- open up the compartment to release the pressure
What is chronic limb ischaemia
Artery becomes narrow and stiff due to athersclerosis which causes a reduced oxygen supply to the tissue
There is collateralisation (new blood vessel formation) to allow blood flow pass around it
What are the signs and symptoms of chornic limb ischaemia
- claudication: pain that comes on when you do a certain exercise
- rest pain
- absent pulse
- arterial ulcers: blood suply is enough to keep the tissue alive but not for healing
- skin changes
