Why am I having this test?
Once the arteriovenous fistula has been created it is important to ensure that it remains in good working condition. During the early development stage your doctor may ask that the fistula is scanned to ensure it is maturing adequately. If you are already using the fistula your dialysis nurses/renal doctors may request that the fistula is imaged if they notice any problems during dialysis; for example needling problems, high/low venous pressures or prolonged bleeding after the needles are removed.
What are we looking for?
The arteriovenous fistula ultrasound scan will involve the inflow (artery) and outflow (vein). We use b-mode, colour and pulsed wave doppler to map the fistula and measure the volume of flow passing through the fistula. We will access for any significant narrowing or dilation that may result in difficulty using the fistula for dialysis.
What will I need to do for the test?
Arrive 5 minutes before your appointment time to allow any paperwork to be completed. Once you have been called into the ultrasound room you will need to remove some clothing. The sonographer will let you know exactly what you need to remove depending on the location of your fistula. If your fistula is in the upper arm (at the elbow level) you will likely need to take off any clothes that cover your arms/shoulder area. If you are wearing a singlet you may be able to leave this on. Leave your bra on if you are wearing one although the sonographer may need to move the strap slightly whilst scanning across the shoulder area. Once you are ready the sonographer will instruct you to either lie down on the bed or sit on the side of the bed. The gel will be cold and the ultrasound probe will be pressed gently across your arm in the region of the fistula. In some cases the entire arm up to the neck may need to be imaged to fully assess the fistula. Your sonographer will instruct you if you need to move your arm to ensure all the veins and arteries can be imaged. The scan usually takes 15-30 minutes.
How will I get my results?
The sonographer will check through the images and produce a worksheet with the relevant information which is then rechecked by the vascular surgeon. If you are seeing one of our specialists on the same day as the scan then they will be able to give the result immediately. Otherwise your report will be sent back to the referrer within a day or two. You can contact the referer to arrange a time to discuss the results. If the sonographer identifies any urgent problems then they will discuss it with our vascular specialists and your referrer immediately and let you know if you need to do anything further.
