Arterial

• Arterial ulcers, also known as ischemic or arterial insufficiency ulcers, stem from inadequate blood supply to the extremities.

  • Usually due to atherosclerosis
  • Arterial narrowing and comprised blood flow
  • Diminished perfusion deprives tissues of oxygen and nutrients, resulting in tissue damage and ulceration
• Location:

  • Predominantly occur on the lower extremities near end-arteries
  • Toes
  • Heels
  • Lateral malleolus
• Pain:

  • Severe, resting pain due to ischaemia
  • Especially painful at night - pain worsens when legs are elevated
• Appearance and features:

  • Often appear pale, dry (minimal exudate) and gangrenous with cool surrounding skin
  • Sharply defined and have a deep 'punched-out' appearance
  • Loss of hair on surrounding skin (shiny appearance)
  • Less likely to bleed than venous ulcers
  • Thick nails
  • Gangrene
• Pulses:

  • Diminished or absent pulses, especially in the affected limb, are a hallmark sign
• Investigations:

  • Doppler ultrasound: non-invasive test to assess blood flow and identify arterial stenosis
  • Ankle-Brachial Pressure Index (ABPI): measures the ratio of systolic blood pressure at the ankle to that in the arm. ABPI <0.9 indicated arterial insufficiency
  • Angiography: may be necessary to visualize arterial anatomy and plan interventions
• Management:

  • Good analgesia to control ischaemic pain
  • Lifestyle promotion - smoking cessation, exercise and control of comorbidities. Reducing blood lipid and sugar levels reduces the risk of further ulcer development
  • Wound management - dressings should maintain a moist wound environment
  • Compression bandaging and anti-embolism stockings are contraindicated if arterial ulcers are present as this could further reduce distal blood flow
  • Vascular reconstruction - surgical bypass or angioplasty (stenting) to restore blood flow
• Peripheral arterial bypass graft:

  • Bypass the diseased section and connect a higher up functioning artery to a lower down functioning artery to restore supply to the leg beyond the level of disease
  • Bypass procedure names depend on where the bypass starts and finished e.g. femoro-popliteal
  • Artificial grafts are used when bypassing large arteries
  • Patient's vein (usually long saphenous) is used when bypassing smaller arteries
• ABPI:

  • Ratio of systolic BP of brachial artery and the dorsalis pedis + posterior tibial arteries
  • Take BP from right and left arm and record higher of the two
  • Take blood pressure at ankle using BP cuff and hand help doppler
  • Take higher pressure from posterior tibial or dorsalis pedis
  • > 1.4 - calcified vessels can cause unusually high ABPI result. warrants further assessment
  • < 0.9 - mild to moderate arterial disease
  • < 0.5 - severe arterial disease - urgent referral for vascular assessment
• Buerger's test:

  • With the patient supine, elevate both legs and assess at which angle the leg becomes pale - Buerger's angle
  • Pallor occurs when peripheral arterial pressure is inadequate to overcome the effects of gravity
  • Angle less than 90 indicates severe limb ischaemia
  • hold legs at 45 degrees for 1-2 minutes
  • Ask patient to hang legs over the side of the bed
  • Skin first becomes blue as blood is deoxygenated it its passage through the ischaemic tissue
  • Skin then becomes red due to reactive hyperaemia from post-hypoxic vasodilatation (driven by anaerobic metabolic waste products)