VASCULAR SURGERY Flashcards
Does chronic limb ischaemia usually affect the upper or lower limbs?
Lower, but patients often have a history of other ischaemic problems such as angina
What are the risk factors for developing chronic lower limb ischaemia?
Atherosclerosis Diabetes mellitus Hyperlipidaemia Family history Smoking Buerger's disease
What is Buerger’s disease?
Recurring progressive inflammation and thrombosis of small and medium arteries and veins of the hands and feet. It is strongly associated with smoking.
What are the three stages of chronic limb ischaemia?
Intermittent claudication
Rest pain
Gangrene or ischaemic ulceration
What is intermittent claudication?
Cramp like pain in the legs (most often calf) exacerbated by exercise and relieved by rest. Pain develops distal to the obstruction.
What does pain at rest signify about chronic lower limb ischaemia?
That it has reached a critical stage where the viability of the leg is threatened. The artery is almost completely occluded at this point.
What are the two types of gangrene?
Wet
Dry
What is dry gangrene (as opposed to wet gangrene)?
Death of tissue. Tissue becomes black and there is a clear line of demarcation. No infection.
What is wet gangrene (as opposed to dry gangrene)?
Tissue is infected with pathogenic bacteria so infection will spread proximally and can cause systemic toxicity. The tissue will appear brown, moist and ulcerated.
What investigations would you do in someone who presented with intermittent claudication?
FBC - Aneamia, polycythemia
Lipidaemia
U&Es
BM - diabetes
How do you assess the vasculature of someone with intermittent claudication?
ABPI (ankle/brachial pressure measurement)
Doppler ultrasound
Arteriography
How would manage someone who was the in the first stage of chronic limb ischaemia (intermitent claudication)?
Advise cessation of smoking Encourage exercise Prescribe 75mg Aspirin Prescribe a statin Control diabetes
How do you manage someone who presents with critical limb ischaemia (pain at rest/ulceration/gangrene)?
Heparinise, rehydrate and oxygenate them.
Send them for arteriography
A patient presents to you with critical limb ischaemia. You heparinise him, give him fluids and oxygen. The arteriogram shows a single short segment of blockage less than 5 cm long. How you manage this patient?
If less than 5cm balloon angioplasty can be used. Success rate of 85%.
A patient presents to you with critical limb ischaemia. You heparinise him, give him fluids and oxygen. The arteriogram shows a single segment of blockage more than 5 cm long. How you manage this patient?
A ballow angioplasty is not likely to be successful due to the length of the blockage. Use an expandable metal stent.
A patient presents to you with critical limb ischaemia. You heparinise him, give him fluids and oxygen. The arteriogram shows multisegment disease. How do you manage this patient?
Revascularisation through reconstructive surgery (bypass). Bypass surgery can either use a vein (in-situ or reversed) or a synthetic tube.
How is aortoiliac disease (blockage) causing critical limb ischaemia surgically treated?
Synthetic bifurcated graft from the aorta (proximal to blockage) to both femoral arteries (distal blockage)
How is aortoiliac disease (blockage) causing critical limb ischaemia surgically treated in someone who unfit for major abdominal surgery?
A graft can be passed from the axillary artery to the femoral artery under local anaesthetic.
What are the usual causes of acute limb ischaemia?
Embolus or throbosis Vascular injury (after trauma or intervention such as arteriography)
What are the six P’s of acute limb ischaemia?
Pain Perishing with cold Pallor Pulselessness Paraesthesia Paralysis
What does muscle rigidity imply in someone with acute limb ischaemia?
That the damage is irreversible
What are the main originating sites of an embolus that causes acute limb ischaemia?
Mural thrombus (in AF or site of previous MI)
Heart valves
Atrial myxoma
Atheromatous plaque
If there is no history of intermittent claudication in a patient with acute limb ischaemia, then what is the most likely cause?
Embolus
If there is a history of intermittent claudication in a patient with acute limb ischaemia, then what is the most likely cause?
Thrombus
How do you manage someone with acute limb ischaemia likely to be caused by an embolus (rather than chronic limb ischaemia and thrombus)?
Heparinise them
Embolectomy under local anaesthetic
What is used to extract an embolus in someone with acute limb ischaemia?
Fogarty balloon catheter
How do you manage someone with acute limb ischaemia likely to be caused by acute on chronic limb ischaemia (thrombus rather than embolus)?
Arteriogram is needed Thrombolytic therapy (streptokinase or similar) - cannot be used if viability of limb is threatened Reconstructive surgery - bypass
In ischaemic limb patient in whom reconstructive surgery fails or is not possible, how do surgeons decide on the type of amputation?
Level of adequate blood supply
Suitability for prosthetic limb
What are the indications for limb amputation?
Irreversible ischaemia Refractory ulceration Extensive rhabdomyolisis Malignancy Severe infection Congenital deformity Paralysed 'useless' limb
What percentage of leg amputations are a consequence of vascular disease?
80%
What are the common sites of amputation?
Above knee Through knee Below knee Transmetatarsal Ray amputation of digits
What is a common complication of limb amputation?
Severe phantom limb pain
How do you manage a patient following amputation?
Physiotherapy
Occupational therapy - prosthesis
Counselling (if needed)
What is an aneurysm?
Abnormal dilatation of a vessel by more than 50%
What are the common arterial sites that aneurysms occur?
Abdominal aorta Iliac Thoracic aorta Femoral Popliteal Cerebral
What is the difference between a true and a false aneurysm?
A true aneurysm is one that involves all three layers of the wall of an artery (intima, media and adventitia)
A pseudoaneurysm, also known as a false aneurysm, is a hematoma that forms as the result of a leaking hole in an artery. Note that the hematoma forms outside the arterial wall, so it is contained by the surrounding tissues.
What is the difference between a fusiform vs a saccular aneurysm?
Saccular aneurysms are spherical in shape and involve only a portion of the vessel wall; they vary in size from 5 to 20 cm (8 in) in diameter, and are often filled, either partially or fully, by a thrombus.
Fusiform aneurysms (“spindle-shaped” aneurysms) are variable in both their diameter and length; their diameters can extend up to 20 cm (8 in). They often involve large portions of the ascending and transverse aortic arch, the abdominal aorta, or less frequently the iliac arteries.
What is the most common cause of aneurysm?
Atherosclerosis
Other than atherosclerosis, what are the causes of aneurysm?
Congenital
Infection - mycotic or syphilitic
Trauma - eg intervention radiology
What is the name given to an aneurysm in the circle of Willis?
Berry aneurysm
What is the most common cause of Berry aneurysm?
Congenital
How might someone with an abdominal aortic aneurysm present?
Asymptomatic - detected during routine examination
Abdominal pulsation
Recent onset severe back pain / flank pain
Hypotension
Circulatory collapse and severe abdominal pain - rupture
Signs of CHF, abdominal bruit, oedema - erosion into vena cava
What is the mortality rate for a ruptured abdominal aortic aneurysm?
80%
What are the risk factors for developing an abdominal aortic aneurysm?
Age Male (5:1) Smoking Hypertension Faimly history Connective tissue disorder (Ehlers Danlos)
What is the risk of an AAA that is 3 cm in diameter rupturing in the next year?
0.4%
What is the risk of an AAA that is 4 cm in diameter rupturing in the next year?
1%
What is the risk of an AAA that is 4.5 cm in diameter rupturing in the next year?
2%
What is the risk of an AAA that is 5 -5.9 cm in diameter rupturing in the next year?
9%
What is the risk of an AAA that is 6 - 6.9 cm in diameter rupturing in the next year?
19%
What is the risk of an AAA that is over 7 cm in diameter rupturing in the next year?
34%
What diameter must an AAA reach for the benefits of elective surgery to outweigh the risks?
5.5 cm
How is an AAA repaired electively?
Stent
Endovascular aortic aneurysm repair (EVAR) - stent delivered via the femoral artery
Fenestrated endovascular aortic aneurysm repair (FEVAR)
What are the complications of surgical repair of an AAA?
Lower limb ischaemia due to thrombus or embolus
Colonic ischaemia
Spinal cord ischaemia
Graft infection
Aortoenteric fistula
False aneurysm at site of anastomosis (post surgery for ruptured aneurysm)
What are varicose veins?
Tortuous, dilated, superficial veins with incompetent valves.
What are the veins that usually become varicose veins?
Long and short saphenous veins of the leg
What is the name of the congenital syndrome comprising of varicose veins, limb hypertrophy and a port wine stain?
Klippel-Trenaunay syndrome
What proportion of the population of over 40 year olds are affected by varicose veins?
50%
What are the risk factors for developing varicose veins?
Family history Female (5:1, although 2:1 after 6th decade) Age over 50 Multiparity (having more than one child) Prolonged standing Obesity Previous DVT
What are the symptoms of varicose veins?
Often asymptomatic Cosmetic dissatisfaction Aching Itching Heavy legs Swelling
What are the signs of varicose veins?
Distended veins on standing Telangiectasia (small red or purple clusters on the skin) Eczema Mild pitting oedema Ulceration
How might you further investigate someone who presents with varicose veins?
Clinical examination or Duplex scan to find level of incompetent vein
Venogram to check for thrombosis (only if there is history of thrombosis)
How would manage someone with varicose veins?
Elevation
Support hosiery (stockings)
Laser/radiofrequency ablation
Open surgery - stripping, high tie (disconnection from femoral vein), ligation, avulsions
What are the complications of surgically treating varicose veins?
Recurrence Nerve damage Bruising Infection Bleeding DVT Pigmentation
What is the most common point of incompetence in people with varicose veins?
The saphenofemoral junction
What is lymphoedema?
Failure of the lymphatic transport system, resulting protein rich fluid accumulating in the subcutaneous tissue.
What is the difference between primary and secondary lymphoedema?
Primary - Congenital abnormality,
Secondary - interruption or blockage of lymphatic channels
What are the causes of secondary lymphoedema?
Surgical excision
Infection
Tumour infiltration
Radiotherapy
What are the clinical features of lymphoedema?
Painless diffuse swelling in a distal to proximal distribution
Hyperkeratosis
Sausage shaped toes
Stemmers sign
What is hyperkeratosis?
Thickening of the outer layer of skin
What is Stemmer’s sign?
Inability to pick up a fold of skin at the base of the second toe
How do you manage someone with lymphoedema?
First exclude other causes (eg heart failure)
Supportive treatment: skin care, elevation, support hosiery (stockings)
Manual lymphatic drainage (massage)
Surgery
How can you tell the difference between an ischaemic and a neuropathic ulcer in a diabetic patient?
Ischaemic: Painful No pulses Ulceration on toes and pressure areas Cold to touch Associated with intermittent claudication
Neuropathic: Sensory impairment Pulses present Plantar ulceration - deep and painless Warm due to autonomic neuropathy Associated with trophic skin lesions, Charcot's joints
