Vascular
CASE 47: DiabetiC Foot
history
A 54-year-old insulin-dependent diabetic woman has come to the emergency department complaining of increasing pain in the right foot for the past week. The pain is worse at night and is relieved by hanging her leg over the side of the bed. For the past few days she has noticed swelling, redness and discolouration over the base of the big toe. Her glucose control has been recently reviewed by the general practice nurse and her insulin regimen changed.
examination
She is afebrile, her pulse is 86/min, her blood pressure is 130/60 mmHg and her blood glucose is 13.2 mmol/L on BM stick testing. Femoral pulses are palpable bilaterally. No popliteal, posterior tibial or dorsalis pedis pulses are palpable in either limb. The great toe is erythematous with a large fluctuant swelling at the base.
INVESTIGATIONS
an x-ray of the foot is shown in Figure 47.1.
Figure 47.1 plain x-ray of the foot.
Questions
•What do the clinical appearances suggest?
•What does the x-ray show?
•What other investigations does she require?
•How would you manage this patient?
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100 Cases in Surgery
ANSWER 47
This patient has peripheral vascular disease and poor diabetic control. Examination describes swelling and erythema over the base of the first metatarsal, which may indicate an underlying collection of pus. A full vascular examination should be carried out and ankle–brachial indices measured. All areas of the foot, especially between the toes and the heel should be examined for other areas of ulceration, and the foot examined for the presence of diabetic neuropathy.
Investigations should include:
•Full blood count
•Renal function and C-reactive protein
•Blood sugar
•Foot x-ray
The patient should be commenced on intravenous broad-spectrum antibiotics and an insulin sliding scale. The priority is to release the pus and debride necrotic tissue. The x-ray changes (osteopenia, osteolysis, sequestra and periostial elevation) suggest there is underlying osteomyelitis (Figure 47.2). This will also need to be debrided in order to remove all the infection.
Figure 47.2 osteomyelitis in the metatarsophalangeal joint of the great toe (arrows).
A duplex scan or intra-arterial angiogram should then be carried out to ascertain whether the blood supply to the foot is compromised and whether any revascularization procedure is necessary. As a rule, revascularization should be carried out prior to any surgical debridement/amputation in order to ensure that the blood supply is adequate for tissues to heal. In this particular case, however, delaying surgery would result in further damage to the foot. Revascularization of the foot should be carried out as soon as possible after surgery.
KEY POINT
•Diabetic feet are at risk of ischaemia (progressive distal ischaemia) and neuropathy (sensory, motor and autonomic), and are more prone to infections.
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Vascular
CASE 48: SuDDen arm pain
history
A 59-year-old woman presents to the emergency department with pain and tingling in the right arm. The pain occurred that morning while she was walking the dog. It was sudden in onset and has improved since arriving in the department. There is no history of trauma and she has had no previous episodes. She is now able to move her fingers, but says they feel numb. Her previous medical history includes intermittent episodes of palpitations for which she is waiting to see a cardiologist.
examination
The right hand appears pale and feels cool to touch. The radial and ulnar arterial pulses are absent. There is no muscle tenderness in the forearm and she has a full range of active movement in the hand. Sensation is mildly reduced.
INVESTIGATIONS
an urgent angiogram is performed (Figure 48.1) and an eCg (Figure 48.2).
Questions
• |
What is the likely diagnosis? |
• |
What is the probable aetiology? |
• |
What other aetiologies do you |
|
know for this condition? |
• |
How would you investigate and |
|
manage this patient? |
Figure 48.1 angiogram of the right upper limb.
I |
aVR |
v1 |
v4 |
II |
aVL |
v2 |
v5 |
III |
aVF |
v3 |
v6 |
II |
|
|
|
Figure 48.2 electrocardiogram.
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100 Cases in Surgery
ANSWER 48
This patient has an acutely ischemic arm secondary to arterial embolism (arrow in Figure 48.3).
Figure 48.3 angiogram showing an occlusion of the brachial artery.
The embolus is likely to have originated from the left atrium as the patient has atrial fibrillation (shown on the ECG).
Other aetiologies include:
•Cardiac arrhythmias (most commonly atrial fibrillation)
•Aneurysmal disease
•Procoagulant state caused by underlying malignancy
•Thrombophilias
•Atrial myxomas
Investigations aim to determine the aetiology of the embolism and to prepare the patient for theatre:
•Full blood count (polycythaemia)
•Clotting
•Group and save
•ECG (arrhythmias)
•Chest x-ray (underlying malignancy)
The patient should be given intravenous unfractionated heparin, analgesia and resuscitated with intravenous fluids. Loss of sensation and paralysis in the affected limb (signs of advanced ischaemia) are indications for urgent embolectomy. A postoperative echocardiogram is arranged if preoperative investigations do not reveal an obvious cause for the embolism. This investigation can detect cardiac thrombus or an atrial myxoma.
KEY POINTS
Signs and symptoms of acute limb ischaemia – the six ps:
•pain
•pulseless
•pallor
•paraesthesia
•perishingly cold
•paralysis
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