Vascular surgery Flashcards
What are the vascular risk factors?
Smoking
Family history
Hypertension
Renal failure
Diabetes mellitus
High cholesterol
Give examples of disease in coronary and carotid territories.
Coronary: MI, angina, coronary revascularisation.
Carotid: Stroke, TIA, amaurosis fugax, carotid intervention.
How is vascular disease prevented?
Antiplatelet medication.
Statins.
Risk factor modification.
What is claudication?
Pain that becomes worse with exercise- usually in calves, thigh or buttocks.
Measured in metres- how far can you walk without pain - claudication distance
Reproducible- claudication distance is fixed- always the same
Peripheral vascular disease- ischaemia- muscle doesn’t get enough oxygen.
Impact on social function, QOL.
Need to differentiate from nerve root compression.
What is critical ischaemia?
Rest pain requiring analgesia >2 weeks, or tissue loss.
Limb involved is always ischaemic- constant pain- black, blue, ulcers, cold, etc.
Forefoot/toes.
Night.
Relieved by dependency.
Gangrene/ulceration.
Never enough blood with oxygen.
What is rest pain?
In pain at rest, peripheral vascular disease, sign of critical ischaemia.
What is the prognosis and what makes it worse for patients with intermittent claudication?
80% chance of improving/stable. 20% chance of getting worse. 5%- intervention, 1%- major amputation. 15%- dead 5 years stroke/MI. -Diabetes mellitus. -Smoking. -Occlusive disease below the knee.
What is the prognosis for patients with critical limb ischaemia?
90%- intervention within 1 year.
25%- major amputation.
50%- dead within 5 years MI/stroke.
Which of the following describes ischaemic rest pain?
a) it is cramping in nature
b) it is typically felt in the calf at night
c) it indicates impending limb loss
d) it is relieved by leg elevation
It indicates impending limb loss.
What is ankle brachial pressure index?
Compare BP in leg to arm. Ankle SBP/Brachial SBP. Normal 0.9-1. Claudication 0.6-0.9. Single level occlusion >0.5. Multi-level occlusion <0.5. Rest pain/gangrene 0.3.
Calcification can alter results- diabetes- incompressible arteries- spuriously high ankle pressures.
Which of the following is NOT true with respect to ABPI measurements?
a) ABPI <0.9 almost always indicates significant arterial disease
b) claudicants have on average ABPI of 0.6
c) in limbs with rest pain and gangrene the ABPI is typically 0.3
d) ABPI is the investigation of choice in diabetes.
ABPI is NOT the investigation of choice in diabetes.
How can you image arteries?
Duplex ultrasound.
Angiography.
Magnetic resonance angiography.
What are the advantages of duplex ultrasound?
Non-invasive.
Fast/cheap.
Few complications.
What are the disadvantages of duplex ultrasound?
Dependent on ultrasonographer’s ability.
Poor visualisation below the knee.
What are the advantages of angiography?
Gold standard for demonstrating anatomy.
Provides therapeutic opportunities, e.g. PTA.
What are the disadvantages of angiography?
Invasive: risk of haemorrhage, aneurysm, infection.
Contrast in nephrotoxic.
What are the different types of diabetic foot?
45% neuropathic.
10% ischaemic.
45% mixed.
What are the 6Ps of acute limb ischaemia?
Pain Pallor Perishing cold Pulseless [Signs of critical disease] Paraesthesia Paralysis
Surgical emergency.
What are all the causes of acute limb ischaemia?
Thrombosis.
Embolism.
Trauma.
Iatrogenic.
Thrombosed popliteal artery aneurysm.
Graft thrombosis/post angioplasty.
What are all the possible treatments for acute limb ischaemia?
Analgesia. Heparin. Catheter. IV access & fluids. Consent. Embolectomy ± fasciotomies/ thrombectomy. Thrombolysis.
What is the most likely aetiology of ‘trash foot’?
a) infective endocarditis
b) SFA occlusion
c) abdominal aortic aneurysm
d) popliteal aneurysm
e) all of the above
Abdominal aortic aneurysm.
What is carotid artery disease?
[*Not in lecture]
Stroke: completed (deficit lasting >3 weeks), TIA (symptoms resolve completely <24hrs).
Amaurosis fugax = transient blindness in one eye.
Necrotic plaque in arteries ruptures, debris discharged; ulcer, platelet deposition, platelet emboli; trauma (carotid dissection).
What is the epidemiology of stroke?
[*Not in lecture]
700,000 new stroke patients yearly. Mortality rate of 10-35%, 30% die within 1yr. 3rd leading cause of death. Annual cost of stroke >50 billion. 27% haemorrhagic, 71% ischaemic.
How is carotid artery disease diagnosed?
[*Not in lecture]
History (TIA, stroke), physical exam (carotid bruits).
Carotid duplex/ doppler US.
CT/MR brain, CTA aortic arch and carotids.
Angiography.
How is carotid artery disease treated?
[*Not in lecture]
Symptomatic: >70% ICA stenosis (ESCT, SACET), carotid endarterectomy = CEA, 17% risk reduction at 2 years; 50-69% ICA stenosis (NASCET), CEA, 6% risk reduction at 5 years; 30-50% ICA stenosis (NASCET), BMT.
Asymptomatic: BMT, 50% risk reduction; aspirin, clopidogrel, dipyridamole; statin.
What is DVT?
[*Not in lecture]
Deep vein thrombosis.
Detected by scanning- d-dimers.
Treated by anticoagulation, compression, adequate analgesia and adequate rehydration.
What are varicose veins?
[*Not in lecture]
Common- 10% of population. Superficial veins. Valve dysfunction. Bulging veins. Chronic venous insufficiency: leg swelling, skin colour and texture changes, venous ulcers.
What is the treatment or varicose veins?
[*Not in lecture]
High frequency ultrasound/ laser ablates vein under ultrasound guidance and local anaesthetic.
What is an aneurysm?
A permanent localised dilatation of an artery, at least >1.5 original vessel diameter.
Ectasia.
What is a true aneurysm and what are the causes?
Dilatation of all layers of arterial wall.
Degenerative- atherosclerotic. Connective tissue- Marfan's. Post-dissection- thoracic/ type B. Infection- syphilitic, salmonella. Inflammatory- takayasus, PAN. Congenital.
What are false aneurysms?
Doesn’t involve all arterial layers
Traumatic, connective tissue wall, post haematoma.
What are the different types of aneurysms?
Saccular- protrusion on one side
Fusiform- all around ballooning of artery
Pseudoaneurysm.
What are the clinical features of aortic aneurysms?
What are the symptoms?
Most are asymptomatic (75% incidental)- until rupture
Symptomatic (25%):
- rupture
= generalised abdominal/flank/back pain.
or rarely-
- compression = sciatica, leg swelling, vomiting, hydronephrosis.
- fistulation = aorto-duodenal, aorto-caval fistula.
- distal embolisation.
Surgical emergency.
How are aortic aneurysms investigated?
> Physical exam: palpation around (up+left) umbilicus.
> USS- duplex [cannot see rupture though, hard in obese patients, limit in how far you can see]
> CT AORTA with contrast - Gold standard- can plan EVAR
> Can also do angiography- but can underestimate diameter- mural thrombus mimic aortic wall
What is the rupture risk of abdominal aortic aneurysms?
Low <1% with diameter <5.5cm.
Rises to 10%/year over 6cm, 25%/year over 7cm.
Do elective repair if over 5.5cm
A 67 y/o man comes to the clinic and describes pain in both calves after walking 50m.
He is a smoker and has had diabetes for many years.
Imaging reveals that he has severe arterial disease in his femoral arteries and vessels distal to them.
What is this symptom best described as?
Intermittent claudication.
A 68y/o man comes to the clinic with a 3yr history of leg ulcers treated unsuccessfully by district nurses with dressings.
A scan shows normal arteries, but bilateral incompetence of both his great saphenous veins.
He is otherwise fit and well and mobilises easily.
What is the most appropriate next step in management?
Ablation.
What is a bypass?
Which veins can be used for which infra inguinal [lower limb] bypasses?
Provide alternative routes for blood to flow around blockage using grafts [either veins from another part of body or synthetic material
Align valves in right way/remove valves
Sites Femoral - Above knee popliteal - Below knee popliteal - Anterior tibial - Posterior tibial
Popliteal
- Pedale
Which grafts are better for a bypass- vein or synthetic?
Vein grafts- less risk of infection/more patency
Synthetic- made of Dacron/PTFE not as good
When should you treat acute limb ischemia by?
6hrs of presentation
Unless dead limb- then don’t treat, just amputate
Should you revascularize a dead foot?
No
All breakdown products go back into blood stream
What are the features of a viable, threatened and dead limb?
Viable
audible tibial/ankle pulse on doppler
Threatened
No sound of doppler
Sensory loss
Tense calf
Dead
Discolouration- fixed mottling
Tissue loss
Neurological deficit
What are the main causes of acute limb ischemia?
What are the features of acute limb ischemia presentation due to each cause?
Thrombotic
- Atherosclerotic disease- in situ thrombosis- due to plaque injuring endothelium
- Less acute
- History of PVD- claudication
- Abnormalities in other limb too
Embolic
- Sudden
- No Hx of PVD
- Opposite leg is fine
What are the causes/origin sources of embolic acute limb ischemia?
AF- eighty percent
Post MI- ten percent
Aneurysm - aortic/popliteal- ten percent
Initial investigations for acute limb ischemia?
- FBC
- Group and Save, Cross match
- ECG- for AF
- CXR- cardiac?
- Cardiac enzymes- silent MI
- ABPI
- Duplex USS, angiogram - if time
Initial management for acute limb ischemia?
Analgesia [if pain- foot not numb] Heparin Catheter IV access and fluid Consent for surgery
How to define an abdominal aortic aneurysm?
> 3cm
or 1.5 x normal diameter [1.2-2 cm] [women have smaller aorta than men]
How is the location of AAA defined?
- Juxta renal
- Infra renal
Defined by relationship to renal vessels
Are most AAAs juxta renal or infra renal?
Infra renal
Causes of AAA
Atherosclerotic
Inflammatory
Used to be mainly tuberculous/syphilic in past
Epidemiology of AAA
Male > female - 8:1
Older age
Increasing prevalence : aging population, better detection
5% of men over 65 years have a AAA
Third most common cause of sudden death in UK
Risk factors for AAA
Age
Smoking
HTN
Atherosclerosis
How does smoking affect AAA?
Increased growth rate
More proximal AAA
What increases risk of AAA rupture?
Female -3:1
Diameter >5.5cm
Mean arterial blood pressure- HTN
Smoking
Reduced FEV1
Are AAA regularly screened for?
Yes
Cost effective
Reduces mortality
Complications of AAA
Embolisation of mural thrombus- due to bad blood flow through aneurysm
- Sudden- acute ischemia + pain
- Insidious- trash foot- intermittent claudication, rest pain, ulcers
Fistula- aortoenteric- to duodenum- upper GI haemorhharge
- aortocaval- aorta + inferior vena cava
How do you assess a AAA patient pre operatively- what factors do you consider?
Resp assessment
Renal assessment
Cardiac assessment- modify risk factors- smoking
Age over eighty year- operative mortality doubles
Check for asymptomatic cancer
Weigh up risks vs benefits
Especially if elective- due to screening programme- not rupture
Complications of EVAR?
Stent migration
Endo leak- 5 types- blood accumulation
Higher mortality years after operation
A 66 year old man attends A and E
Acute tearing abdominal pain
Cold and clammy
BP: 90/60
HR: 110
Tender abdomen
Pulsatile abdominal mass
Diagnosis?
AAA
Mrs X- painful bilateral ulcers around ankles for one year.
Non smoker
Mobilises well
Foot pulses present
ABPI 0.98
Venous scan- patent deep venous system- working normally
but
bilateral incompetent great saphenous veins
a] Compression Hosiery
b] Four layer compression bandaging
c] Stripping of incompetent great saphenous veins, followed by compression bandaging
d] Laser ablation of incompetent great saphenous veins + compression bandaging
e] Oral broad spectrum abx + Four layer compression bandaging
Laser ablation of incompetent great saphenous veins + compression bandaging
