Scans

Arterovenous Fistula Duplex Ultrasound

Indications:

  • Decreased pulsatility
  • Absence of bruit or thrill in site
  • Pulsatile or expanding swelling of graft
  • Increased return venous pressure
  • Poor arterial inflow
  • Difficulty with fistula cannulisation
  • Increased circulation time
  • Withdrawal of blood clots from fistula site at the time of cannulation
  • Distal limb ischemia
  • Venous hypertension
  • Surveillance of fistula; for assessment of developing fistula and matured fistulas

Contraindications and limitations:

  • Open wounds, Surgical wound/dressing

Patient preparation:

  • On the day of the ultrasound, refrain from applying oils or moisturisers to the lower limb being examined

PLEASE BRING RELEVANT, PREVIOUS DIAGNOSTIC REPORTS AND ULTRASOUND WORKSHEETS TO YOUR ULTRASOUND AND DOCTORS APPOINTMENT

What to wear:

Loose clothing that will allow easy access to the fistula and to the proximal and distal (top and bottom) arteries and veins, of the limb. This includes the clavicular region (collar bone region), axillar (arm pit) and the arm, for arm fistulas; lower abdomen, groin, and the lower limb, for leg fistulas.

Ultrasound study technique:

Ultrasound is a non-invasive diagnostic study. The patient will lie on a bed, with the head of the bed slightly elevated for comfort, or in a chair, with their arm supported on a pillow. Ultrasound gel will be applied to the clavicular region (collar bone region), axillar (arm pit) and the arm, for arm fistulas; the lower abdomen, groin, and the lower limb, for leg fistulas. An ultrasound probe will be run over these regions and the fistula site. Particular care will be taken, whilst scanning the fistula, by applying a generous amount of acoustic jelly and applying minimal pressure. If discomfort is experienced, at any time, the patient must inform the ultrasonographer. Occasionally the ultrasonographer may mark the skin with indelible ink, to assist the renal dialysis nurses or physician. Images will be obtained, and the results documented on a worksheet.

Ultrasound study time:

The first ultrasound with VASCAN may take 30-60minutes, per limb. Subsequent, follow-up and surveillance ultrasounds may take less time, approximately 30 minutes, per limb

Results:

A worksheet can be available, if requested. A formal written report will be available within 24 to 48 hours, following the ultrasound examination, Monday to Friday. If the ultrasound findings demonstrate pathology, which may require urgent attention, the referring Doctor will be notified ASAP following the completion of the ultrasound.