Vascular Surgery - Oxford Handbook MCQs Flashcards Preview

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Flashcards in Vascular Surgery - Oxford Handbook MCQs Deck (12):
1

A 61 year old is admitted to A&E with sudden onset of a painful, cold, white right leg. His radial pulse rate is 86 bpm and its rhythm follows no discernable pattern throughout 30 seconds of palpation. Abdominal examination is normal. No pulses are palpable in the right leg and ankle Doppler signals are absent. An ECG confirms the arrythmia but shows no signs of acute ischaemia. Which is the single most likely diagnosis? 

  • Abdominal aortic aneurysm
  • Aorto-iliac dissection
  • Atrial fibrillation
  • DVT
  • MI

Atrial fibrillation

Explanation 

  • The presentation is that of an embolic episode which occluded flow to the femoral artery. 
  • Eighty percent of emboli have a cardiac cause (AF, MI and ventricular aneurysm)
  • Ten percent result from proximal peripheral arterial aneurysms (including aortic aneurysms)
  • Rarer causes of acute leg ischemia include aorti-iliac dissection, trauma, iatrogenic injury, intra-arterial drug use. 
  • No aneurysm was palpable on abdominal examination and aorto-iliac dissection is less likely. 
  • DVT is an unlikely cause of acute lower limb arterial ischemia but this may occur rarely when a DVT embolizes with the resulting embolus passing through a patent foramen ovale - allowing passage from the venous to the arterial system. 

2

A 70-year-old woman develops a cold, painful, right leg. No pulses
are palpable throughout the right leg. She has several risk factors
for atherosclerotic disease. A medical student asks how best to differentiate
between acute and chronic ischaemia. Which is the single most
appropriate advice? 


A History of 40 pack-years of smoking
B History of intermittent claudication
C History of thrombotic stroke
D Presence of femoro-popliteal bypass scar in the left leg
E Presence of foot pulses in the left leg

E. Presence of foot pulses in the left leg 

  • Clinical features indicate:
    • atherosclerotic disease e.g. risk factors for atherosclerosis (smoking, hypercholesterolemia, hypertension)
    • History of peripheral arterial disease 
    • history of coronary artery disease 
    • history of cerebrovascular disease
  • Presence of good contralateral pulses in a patient presenting with absent pulses in one lower limb suggests acute lower limb ischaemia. 

3

A 65-year-old woman with a 40-pack-year smoking history and
type 2 diabetes presents with cramp-like pain in her right calf
after walking 500 metres, relieved by rest. Her symptoms are aggravated
by walking up steep hills. Which is the single most appropriate
management? 


A Amputation
B Diagnostic angiography
C Endovascular stent
D Modification of risk factors
E Reassure and follow up in 6 months

D Modification of risk factors 

Explanation

  • Risk factors:
    • hypertension
    • hypercholesterolaemia
    • diabetes
    • smoking
    • positive family history

4

Why is the ABPI reading in diabetics unreliable? 

Diabetic patients may have calcified incompressible arteries and assessment of the degree of ischemia by measurement of ankle brachial pressure indices may therefore be unreliable. 

5

A 55-year-old man who smokes 40 cigarettes per day presents with
a history of pain in his left calf after walking 100 metres. The pain
goes with rest. He has no symptoms in his thigh or buttock. He has a
good volume femoral pulse but no popliteal or pedal pulses are palpable.
Neurological examination is normal. He undergoes duplex Doppler ultrasound. Which is the single most likely finding of this investigation? 


A Left common iliac artery occlusion
B Left internal iliac artery stenosis
C Left posterior tibial artery occlusion
D Left profunda femoris artery stenosis
E Left superficial femoral artery occlusion

E. Left superficial femoral artery occlusion

Explanation

  • An occlusion is a complete blockage of an artery whereas a stenosis implies narrowing of the vessel.
  • Calf claudication is most commonly caused by superficial femoral arterial disease.
  • Absent popliteal and pedal pulses suggest that significant symptomatic arterial disease exists proximal to the level of the popliteal artery.
  • If the femoral pulse is of good volume, common iliac artery occlusion is unlikely.
  • Disease of the internal iliac artery may cause buttock claudication and/or impotence (Leriche’s syndrome).
  • Common iliac or external iliac disease may cause thigh claudication, in addition to calf claudication.
  • Profunda femoris disease often contributes to thigh and calf claudication, but is unlikely to cause calf claudication in isolation.

6

A 69-year-old man is referred to the vascular clinic after an
abdominal aortic aneurysm was detected coincidentally on ultrasound
examination. The patient is nervous about the diagnosis, has been
researching it on the Internet and has several questions. Which single
statement is correct? 


A Abdominal aortic aneurysms are associated with tobacco smoking,
hypertension, family history, and diabetes mellitus


B Abdominal aortic aneurysms are considered for treatment by surgical
or endovascular repair when they reach a size of ≥5.5cm, in a patient
fit for intervention


C Abdominal aortic aneurysms most commonly involve the aorta at the
level of the renal arteries and below


D Abdominal aortic aneurysms occur in 10% of the population aged
over 65


E Abdominal aortic aneurysm screening is undertaken in the UK using
CT scanning

B Abdominal aortic aneurysms are considered for treatment by surgical or endovascular repair when they reach a size of >5.5cm, in a patient fit for intervention

Explanation

  • Abdominal aortic aneurysms are associated with hypertension, smoking, family history, but not with diabetes mellitus.
  • Other rarer causes include infective causes (‘mycotic’) and connective tissue disorders.
  • The UK Small Aneurysm Trial suggested that intervention for abdominal aortic aneurysms should be undertaken when the aneurysm reaches a threshold diameter of 5.5cm.
  • A national screening programme for aortic aneurysms is being implemented in the UK, in which ultrasound detection is the screening modality of choice.
  • CT would not be an appropriate screening tool due to high radiation dose and cost.
  • Abdominal aortic aneurysms occur in 5% of males over 65 (they are approximately nine times commoner in men than in women).
  • Ninety-five per cent of abdominal aortic aneurysms are infrarenal; 15% extend into the common iliac arteries.

7

A 75-year-old woman has a painful non-healing ulcer over the
left medial malleolus. It measures 4cm in diameter, with a shallow,
superficially infected base, but little evidence of granulation tissue.
Despite meticulous nursing care with compression bandaging in the
community, the ulcer has shown no sign of improvement over 4 months.
She is hypertensive, has angina, chronic obstructive pulmonary disease,
and had a deep vein thrombosis in her left leg 10 years ago. She reports
no symptoms of intermittent claudication or rest pain. On examination
the feet are warm bilaterally, capillary refill time is less than 2sec, both
popliteal pulses are palpable but foot pulses are impalpable in both feet.
The ankle brachial pressure index is 0.78 on the left and 0.76 on the right.
Which single option is the most likely underlying cause for her persistent
ulceration? 


A Chronic lower limb ischaemia
B Diabetic foot disease
C Mixed arterial-venous disease
D Neuropathic ulcer
E Venous insufficiency

C Mixed arterial-venous disease

  • The ulcer is located in the gaiter area of the leg, a characteristic site for
    venous ulcers.
  • A history of deep venous thrombosis may have rendered the deep veins incompetent, predisposing to venous hypertension, skin changes, and ulceration (post-phlebitic syndrome).
  • However, failure to heal despite treatment with compression bandaging
    suggests that there may also be underlying arterial insufficiency, confirmed by reduced ankle brachial pressure indices.
  • Diabetic foot disease affects the foot as a result of the interdependent
    triad of neuropathy, ischaemia, and infection.
  • This ulcer is not characteristic of diabetic foot disease and is painful, so neuropathy is unlikely to be a causative factor.

8

A 79-year-old man on an inpatient ward becomes acutely short
of breath 36h after a right carotid endarterectomy. He has experienced
rapidly worsening shortness of breath over the last 4min. His previous
medical history includes a transient ischaemic attack 3 weeks ago,
myocardial infarction 12 months ago, hypertension, deep vein thrombosis
aged 50, and he has been a lifelong smoker. He has a respiratory rate
of 45 breaths per minute, oxygen saturation of 89% on air, pulse rate
of 120bpm, and blood pressure is 143/78mmHg. He has bruising and
swelling around the wound in his neck. Which is the single most likely
diagnosis? 


A Ipsilateral cerebrovascular accident
B Myocardial infarction
C Pulmonary embolus
D Vagus nerve injury
E Wound haematoma

E Wound hematoma

Explanation

  • A sudden deterioration implies an acute event.
  • Given the history of recent carotid endarterectomy with neck swelling, a wound haematoma compromising the airway must be suspected.
  • This may occur due to bleeding at the site of the arteriotomy, carotid patch blow out, or delayed wound bleeding, which may be arterial or venous in origin.
  • This can rapidly obstruct the airway and prove fatal unless the swelling is relieved— these patients need immediate re-opening of the neck incision, on the ward if necessary, to drain the haematoma, and to apply pressure to the bleeding point, with urgent transfer to theatre.
  • Cerebrovascular accident would usually present with neurological signs.
  • Myocardial infarction is an acknowledged complication of endarterectomy but rarely presents with acute dyspnoea alone.
  • Pulmonary embolus is a rare complication of endarterectomy and the time course following surgery is usually longer.
  • A vagus nerve injury may cause dyspnoea due to adduction of the ipsilateral vocal cord but this would usually be apparent in the immediate
  • recovery period following surgery.

9

A 48-year-old man with type 1 diabetes and peripheral vascular
disease develops an infected ulcer in his right foot. The infection
spreads to involve the soft tissues of the foot resulting in necrosis, he
develops rigors and his diabetes becomes harder to control with insulin.
An amputation is planned and a medical student asks about the procedure
and its likely outcome. Which is the single most appropriate
advice?


A Above-knee amputation is preferred to supracondylar (Gritti–Stokes)
amputation for bilateral amputees
B Diabetics are 50 times more likely than non-diabetics to undergo
major lower limb amputation
C Likelihood of mobility following below-knee amputation is significantly
better than following above-knee amputation
D Postoperative phantom-limb pain is less common in below-knee
amputations than above-knee amputations
E Stump healing rates following below-knee amputation are higher than
following above-knee amputation

C. Likelihood of mobility following below-knee amputation is significantly better than following above-knee amputation

Explanation

  • For bilateral amputees, preservation of limb length is important for
    balance, especially if they are likely to be confined to a wheelchair.
  • The Gritti–Stokes amputation preserves more of the femur than an above-knee amputation.
  • Diabetics are 15 times more likely to require amputation than non-diabetics.
  • Stump healing rates are related to level of amputation and adequacy of blood supply, which is generally better proximally in the limb.
  • There is no evidence to suggest phantom-limb pain occurs less frequently in below-knee amputations.

10

A 23-year-old medical student returning from her elective in
Australia develops a tender, warm, swollen right calf within 12h
of her flight. She smokes five cigarettes daily and takes the oral contraceptive
pill. She has no chest pain or shortness of breath. Which single
investigation is the most appropriate? 


A Ascending venography
B CT pulmonary angiography
C D dimer
D Duplex ultrasound scan
E VQ scan

D. Duplex ultrasound scan

Explanation

  • This student has clinical features suggestive of a deep vein thrombosis.
  • This may be demonstrated by ascending venography, but this requires contrast injection and has been superseded by duplex ultrasound scanning which is sensitive and non-invasive.
  • CT pulmonary angiography is the modality of choice for rapid and sensitive investigation for suspected pulmonary embolus.
  • It has now largely replaced ventilation perfusion (VQ) scans for investigation of pulmonary embolus.
  • D dimers are a sensitive test for deep vein thrombosis but are usually employed as part of a thrombotic screen.
  • The most sensitive, specific, and appropriate investigation in this case is duplex ultrasound of the leg which will demonstrate occlusive thrombus and blood flow disturbances caused by clot.

11

A 22-year-old woman employed on the butcher’s counter at
her local supermarket complains that her fingers become white,
then blue and cold at work. When she warms her hands under the hot
tap they become acutely painful developing a deep red colour. Which is
the single most appropriate management? 


A Oral prednisolone
B Request transfer from her current job to a different role
C Lumbar sympathectomy
D Oral prostacyclin
E Nifedipine 5mg three times daily increasing to 20mg three times daily

B. Request transfer from her current job to a different role

Explanation

  • This woman is exhibiting Raynaud’s phenomenon on exposure of her hands to a cold stimulus.
  • This occurs nine times more commonly in females and characteristically affects young women.
  • The redness of her hands on warming is caused by reactive hyperaemia, not a reperfusion injury, which is often accompanied by pain and paraesthesia.
  • Initial management should be based around conservative measures including avoidance of cold stimuli, stopping smoking, and wearing gloves where feasible. 
  • If this fails, second-line therapy involves treatment with calcium channel blockers, such as nifedipine, in the doses described (E). In debilitating digital vasospasm resistant to other treatments, IV infusions of prostacyclin, titrated against body mass and side effects, may provide respite.
  • Lumbar chemical sympathectomy is occasionally employed to improve cutaneous blood flow and to relieve rest pain in critical leg ischaemia, but has no role here.
  • Steroids are not an appropriate treatment.

12

A 43-year-old office worker, who has had a swollen left leg since
her early teens, has aching in the calf at rest and has developed
a 4cm shallow ulcer, with an erythematous base, above her lateral
malleolus.

A Aorto-iliac arterial disease
B Cellulitis
C Deep vein thrombosis
D Lipodermatosclerosis
E Lymphoedema
F Raynaud’s phenomenon
G Scleroderma
H Superficial femoral artery occlusion
I Superficial thrombophlebitis

E Lymphoedema

  • This lady has a history suggestive of congenital unilateral lymphoedema (Milroy’s disease), associated with hypoplasia of the lymphatic trunks. 
  • Long-term lymphoedema predisposes to skin changes including leg ulcers, fungal infections, and increased risk of cellulitis.
  • The mainstay of conservative management is treatment with compression and expectant management of superficial skin infections with early antibiotic treatment.
  • Lymphoscintigraphy may be helpful in confirming the diagnosis.