Evaluation of peripheral vascular disease : Positioning, inspection, Palpation, Investigations

February 22, 2013 | By | Reply More

Evaluation of peripheral vascular disease : Positioning, inspection, Palpation, Investigations

Positioning and inspection
Ideally the patient should be examined in a warm environment at rest. Inspect the limb at rest in the supine position first, then elevated (passively), and finally dependent. Be sure to expose the entire limb including the foot or hand to allow thorough inspection. If necessary, take any dressings down (or ask for them to be removed if you are not happy to). For venous disease, the patient should also be examined standing.
During supine inspection look for the following.
  • Appearance. Does the skin look chronically ischaemic (lack of hair, poor nails, pale and flaky)? Are there any areas of established skin necrosis (dry gangrene; e.g. apex of digits, between digits, heel of the foot)? Are there changes of chronic venous stasis (prominent veins, venous eczema, lipodermatosclerosis)?
  • Colour. Waxy white suggests acute severe ischaemia, Blue and mottled suggests acute irreversible ischaemia, Dark purple and shiny suggests chronic ischaemia.
  • Colour changes during position. Note the angle at which the skin of the limb blanches when passively elevated. Normal limbs may not blanch at all. An angle of 15° or less suggests severe ischaemia. Note the presence and delay in change in colour when the limb is dependent. Ischaemic limbs slowly turn deep purple.
  • Ulcers. What is the location (medial suggests venous disease; lateral or plantar suggests arterial disease)? Be sure to inspect between the toes/fingers and on the plantar surface of the foot.
  • Venous inspection. Stand the patient up. Inspect for varicose veins. Are they in the long saphenous or short saphenous distribution?
Palpation
  • Temperature. Does the skin feel cold or warm? Is there a transition level?
  • Skin capillary compression and refill. A delay of greater than 5sec suggests significant ischaemia.
  • Peripheral pulses. Start with the most proximal (major) vessels and work distally. Record if the pulse is hyperdynamic (+++), normal (++), reduced (+), or absent (-). Record if there are any thrills palpable.
  • In venous disease, tests of venous competence may be performed .
  • Surgical grafts. Palpate the course of any surgical grafts and record the presence of pulses if present.
Percussion
Look for transmitted thrill. The course of varicose veins may be tracked by presence of a percussion thrill.
Auscultation
Listen for bruits. Are there bruits in the proximal vessels (suggestive of stenosis or previous surgery)?
Investigations
Doppler ultrasound
  • Easy and simple. Can be carried and performed anywhere from outpatients to ITU.
  • May be simply diagnostic, i.e. confirm or refute the presence of flow in a vessel or graft.
  • May be used to evaluate the relative flow in vessels by measuring the pressure at which detectable flow ceases using a compression cuff. The commonest example is ankle-brachial pressure index (ABPI).
  • May be used to evaluate the presence of reflux between.
Colour flow Doppler
  • Combined 2D ultrasound image with Doppler-derived flow represented using colour, superimposed in real time.
  • May be used for assessment of stenoses or vessels or flow characteristics in vessels or grafts.
  • May be used for assessment of reflux between deep and superficial veins.
Direct angiography
  • Either simple or, more commonly, digital subtraction angiography (DSA; used to reduce background image ‘noise’ and convert the arterial images to black for easier viewing).
  • Invasive, requiring direct arterial puncture with the associated risks.
  • Requires IV contrast with the small risk of allergy (relatively contraindicated in renal dysfunction or where renal blood flow is poor).
  • Gives direct views of arterial tree.
Magnetic resonance angiography
  • Provides images of an arterial tree based on the presence of arterial flow during scanning.
  • Safe and non-invasive; requires no contrast.
  • Tends to overestimate degree of stenosis due to very low flow being underrepresented.
CT angiography
  • Requires multislice rapid acquisition (‘helical’/‘spiral’) scanner.
  • Images acquired in arterial phase after IV injection of contrast.
  • 3D reconstruction allows ‘virtual angiogram’ images to be produced.
  • Easy to perform, safe especially where direct angiogram is difficult, e.g. visceral vessels.
  • Requires dose of IV contrast.

Category: Surgery

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