Vascular Surgery Block Flashcards
(117 cards)
When is carotid endarterectomy indicated?
- A moderate (50-79%) blockage of a carotid artery and are experiencing symptoms such as stroke, mini-stroke or TIA (transient ischemic attack).
OR
- A severe (80% or more) blockage even if you have no symptoms.
What are the potential side effects of carotid endarterectomy?
- Stroke (2%)
- Death (1%)
- Pain/numbness around surgical site
- Wound infection (<1%)
- Nerve damage (hoarse voice, numbness/weakness on side of face - usually temporary. Affects 4%)
- Narrowing of carotid artery again (restenosis; 2-4%)
How does the brain receive blood during a carotid endarterectomy?
A shunt is a small plastic tube that diverts blood around the section of the carotid artery being operated on.
The decision to use a shunt is based on surgeon preference and the results of brain blood flow monitoring during the operation.
When the surgeon has accessed the carotid artery, they’ll clamp it to stop blood flowing through it and make an opening across the length of the narrowing. If a shunt is to be used, it will be inserted now.
The surgeon will then remove the inner lining of the narrowed section of artery, along with any fatty deposits (plaque) that have built up.
What is a pseudo-aneurysm (false aneurysm)?
Involve a collection of blood in the outer layer only (adventitia) which communicates with the lumen (i.e. after trauma)
Common in IV drug users and after angiography
Present with pain + pulsatile bleeding
What is amaurosis fugax?
Temporary loss of vision due to interruption of blood flow in the retinal artery or central retinal vein
Symptoms = curtain coming down vertically into field of view. Monocular blindness/fogging/blurring of vision. Typically lasts a few seconds but can last up to hours.
Investigations = Eye + neurological examination. Carotid ultrasound or magnetic resonance angiography. Blood tests for cholesterol and blood glucose.
Prognosis = doesn’t cause permanent visual damage. Indicates atherosclerosis and an increase risk of stroke.
Treatment = Diet changes + medication (aspirin, warfarin); surgery to remove damage. Quit smoking. BP, cholesterol, glucose checks.
What is lupus? What are the symptoms? How is it treated?
Lupus is an autoimmune disease that occurs when your body’s immune system attacks your own tissues/organs. Inflammation caused by lupus can affect many different body systems — including your joints, skin, kidneys, blood cells, brain, heart and lungs.
Symptoms include (having 4+ = lupus diagnosis):
- Butterfly-shaped rash
- Raised red patches on your skin
- You’re sensitive to light
- Ulcers in your mouth or nose
- Arthritis in two or more joints, plus swelling or tenderness
- Inflammation in the lining of your heart or lungs
- Seizures or other nerve problems
- Too much protein in your urine
- Low blood cell counts
- Certain antibodies in your blood
- Results from a blood test called an ANA test that suggest you may have too many “antinuclear” antibodies, which could be a sign of lupus
While there’s no cure for lupus, treatments can help control symptoms.
- NSAIDs (ibuprofen, naproxen)
- Corticosteroids (prednisolone)
- Antimalarials (hydroxychloroquine, chloroquine phosphate)
- BLyS-specific inhibitors (Belimumab)
- Immunosuppressive agents/chemotherapy
- Anticoagulants (warfarin, heparin)
What is an aneurysm?
An artery that is dilated > 50% of its original diameter. Can be fusiform (i.e. AAA) or sac-like (i.e. Berry aneurysm)
What are true aneurysms?
Abnormal dilatations that involve all layers of the arterial wall
What are common causes and sites of aneurysms?
Causes:
- Trauma
- Atheroma
- Infection (mycotic aneurysm in endocarditis; tertiary syphilis especially thoracic aneurysms)
- Connective tissue disorders (i.e. Marfan’s, Ehlers-Danlos)
- Inflammatory (i.e Takayasu’s aortitis)
Common sites:
- Aorta (infrarenal most common)
- Iliac
- Femoral
- Popliteal
At what age are people screened for aneurysms?
Males over 65yrs
What are the signs and symptoms of AAA?
- Intermittent/continuous abdominal pain (radiates to back, iliac fossa, or groin)
- Collapse
- Expansile abdominal mass (expands + contracts unlike swellings that are purely pulsatile)
- Shock
What is the definition of an unruptured AAA?
> 3cm across caused by degeneration of elastic lamellae and smooth muscle loss. There’s a genetic component.
Often no symptoms
When is rupture of AAA more common and what are the options for its treatment?
More common if hypertensive, smoker, female, family history
- Elective surgery (reserve for aneurysms ≥ 5.5cm or expanding at > 1cm/yr or symptomatic)
- Stenting (EVAR - endovascular stent via femoral artery; reduced mortality but higher risk of graft rejection i.e. endoleak)
What is the emergency management of a ruptured AAA?
Mortality - treated = 41%; untreated = 100%
- Warn theatre!
- Do ECG, take blood for amylase, Hb, crossmatch. Catheterize bladder
- Gain IV access with 2 large-bore cannula. Treat shock with O Rh- blood but keep systolic BP ≤ 100mmmHg to avoid rupturing a contained leak
- Take patient straight to theatre
- Give prophylactic antibiotics (i.e. co-amoxiclav 625mg IV)
- Surgery involves clamping the aorta above the leak, and inserting a Dacron graft (i.e. tube graft)
What is a thoracic aorta dissection?
Blood splits the aortic media with a sudden tearing chest pain radiating to the back.
As dissection extends, branches of the aorta occlude sequentially leading to hemiplegia (carotid artery), unequal arm pulses + BP, or acute limb schema, paraplegia (anterior spinal artery), and anuria (renal arteries)
Type A (70%) involves the ascending aorta and Type B is no involvement of the ascending aorta
What is the management for aortic dissection?
- Crossmatch 10u blood
- ECG + chest xray
- CT or transoesophageal echocardiography
- Take to ITU
- Hypotensives: keep systolic at 100-110mmHg: labetalol or esmolol
What hypotensives are used commonly for aortic dissection?
Labetolol
Esmolol
What are the 6P’s of acute ischemia?
- Pallor
- Pulseless
- Painful
- Paralysed
- Paraesthetic
- Poikilothermia (perishingly cold)
What is peripheral arterial disease?
Occurs due to atherosclerosis causing stenosis of arteries via a multifactorial process involving modifiable and non-modifiable risk factors.
65% have cerebral/coronary artery disease
What is the main feature of PAD?
Intermittent claudication (after walking “the claudication distance” and relieved by rest)
What are the cardinal features of critical ischemia?
- Ulceration
- Gangrene
- Foot pain at rest (i.e. burning pain at night relieved by hanging legs over side of bed)
What is Leriche’s syndrome and what are the symptoms to imply Leriche’s syndrome?
Narrowing of iliac arteries
Buttock claudication + impotence
What is the Fontaine classification for PAD (4)?
- Asymptomatic
- Intermittent claudication
- Ischemic rest pain
- Ulceration/gangrene (critical ischemia)
What are signs of PAD?
- Absent femoral, popliteal, or foot pulses
- Cold, white legs
- Atrophic skin
- Punched out ulcers (often painful)
- Postural/dependent colour change
- Buerger’s angle (angle that leg goes pale when raised off couch) < 20º and cap refill > 15s are found in severe ischemia