These ten questions test your knowledge of the diagnosis, investigation and management of acute and chronic limb ischaemia.
Reviewed by: awaiting review
Stem 1 - Question 1
A 60 year old patient presents to his GP with worsening pain in his right leg. The pain comes on in his calf when walking. He’s had intermittent pain for some time now but no pain at rest. He smokes 15 cigarettes a day, his BP is 156/90 and his BMI is 34. His most recent blood tests showed an HbA1c of 48. The GP suspects chronic limb ischaemia.
What might you find on examination?
Absent pedal pulses
Distal right leg red
Distended saphenous vein
Right foot warm to touch
Other signs of limb ischaemia are:
- femoral bruits
- shiny, hairless skin
- cold peripheries and skin
- ulceration of feet
You may find AF in a patient with ischaemic limb pain, but this would more likely be acute than chronic. A distal inflamed right leg might indicate DVT and the dilated saphenous vein may indicate venous insufficiency, rather than an arterial disorder.
Stem 1 - Question 2The GP has the patient remove his shoes and socks, lie down and then raises their leg by 45 degrees. The right foot rapidly goes pale. When the patient sits back up and hangs his foot over the examination table it goes a dusty pink colour. What is the name of this test?
Allen's test is used to check for collateral circulation in the hands before doing an ABG. The Bainbridge reflex is a physiological rise in heart rate in a response to increased atrial pressure. Thomas' test examines hip flexion and Thompson's test is also known as the calf squeeze test and checks to see if the achilles tendon has ruptured.
Stem 1 - Question 3Given the patient’s suspected diagnosis, what is the first line investigation of choice?
Fasting blood glucose
The CT angiogram may be used to identify the location of any stenosis but is usually avoided for two reasons: patients are likely to have reduced kidney function due to renal artery stenosis so there is an increased risk of kidney damage from the contrast, and there is also a risk of dislodging emboli that then migrate to the feet causing 'trash foot'.
Tne ECG may be indicated if you were worried about heart failure, ischaemic damage to the heart or AF. Note that AF would more likely be associated with acute limb ischaemia. A lipid profile may be used in assessing his cardiovascular risk or monitoring and dietary interventions but has no indication here and we already know he is obese. Fasting blood glucose is of no relevance as we already know he is diabetic based on his HbA1c.
Stem 1 - Question 4What classification scheme is used to grade the severity of the patient’s limb ischaemia?
Modified Well's Score
The Rutherford classification is used to assess tissue viability.
Stem 1 - Question 5Which medication might the patient be started on to reduce the risk of further ischaemia?
- Modifying risk factors e.g. diabetes, hypertension, obesity...
- three month supervised exercise programme
- aspirin or clopidogrel
Stem 1 - Question 6Which of the following ulcers described below is the patient most at risk of developing due to his limb ischaemia?
Painful, expanding ulcer on the shin with granulomatous base and violet edges
A shallow ulcer with slough and granulation tissue in the gaiter region, surrounded by eczematous and brown-stained skin
Deep, punched-out ulcer with minimal exudate and granuloma formation, and evidence of necrosis
Deep puncture wound in sole of the foot surrounded by insensate skin
Red, non-blanching shiny tissue on the back of the heel
- A - pyoderma gangrenosum
- B - venous ulcer
- D - neuropathic ulcer e.g. secondary to diabetes
- E - grade 1 pressure ulcer .
His diabetes puts him at an increased risk of a diabetic foot ulcer (D) but the question was specifically asking about the ulcer that could be causes by his vascular condition.
Check out some of our other questions about ulcers.
Stem 2 - Question 1
A patient is sent to the surgical assessment unit by his GP with suspected critical, acute on chronic limb ischaemia of the left leg.
Which of the following is most likely to be a sign that the distal limb is non-viable?
Non-palpable pedal pulses
Fixed staining of skin
Pain on passive movement
Reduced sensation in toes
Stem 2 - Question 2Which medication should be given first in the acute setting to help reverse the cause of the critical limb ischaemia?
The patient will also need oxygen, analgesia and IV fluids. Analgesia will probably be paracetamol and opiates. Don't forget to prescribe laxatives and anti-emetics alongside the opiate.
Source: Royal College of Emergency Medicine.
Posterior to medial malleolus
Posterior to lateral malleolus
Medial edge of the plantar arch
Lateral to extensor hallucis longus
Lateral to extensor digitorum longus
Posterior tibial artery
Anterior tibial artery
Deep plantar artery