Share your insights

Help us by sharing what content you've recieved in your exams


Arteriovenous fistula

An arteriovenous fistula is a surgically created anastomosis between an artery and a vein. Its main use is to dilate a vein for easier access in patients requiring regular haemodialysis.

Arteriovenous fistula diagram

Examining an AV fistula

Look

  • General inspection
    • PatientΒ well/unwell
    • In pain
  • Fistula
    • Type of fistula
      • Radiocephalic AV fistula (most): radial artery to cephalic veinΒ at wrist
      • Brachiocephalic AV fistula = brachial artery to cephalic veinΒ in antecubital fossa
      • Brachiobasilic transposition AV fistula = brachial artery to transposed basilic veinΒ in upper arm
    • Scars
    • Signs of inflammation: rash, erythema, swelling
    • Arm elevation test (for outflow obstruction): fistula should collapse on arm elevation
  • VeinsΒ Β Β Β Β Β Β Β Β Β Β Β Β Β 
    • Presence of collateral veins (suggest venous stenosis)
  • Hands – compare to other side
    • Oedema
    • Signs of ischaemia (Steal syndrome = vascular insufficiency secondary to AV fistula)
Arteriovenous fistula photo

Feel

  • Thrill:Β a thrill is normal but it shouldn’t be pulsatile
  • Consistency:Β should be soft and easily compressible
  • Augmentation testΒ (for anastomotic stenosis): occlude vein 1-2 cm above anastomosis. If arterial pressure is adequately conducted (i.e. there is no anastomotic stenosis), a pulsation in the vein will be seen.Β NB: if vein is pulsatile anyway, there is venous outflow stenosis.

Listen

  • Bruit:Β should be a soft machinery–like rumbling sound (high-pitched = stenosis)

Questions and more details about arteriovenous fistulae

Why is a fistula needed?

Oops! This section is restricted to members. Click here to signup!

How long does it take for an AV fistula becomes patent?

Oops! This section is restricted to members. Click here to signup!

How is an AV fistula used?

Oops! This section is restricted to members. Click here to signup!

What are the complications of an AV fistula?

Oops! This section is restricted to members. Click here to signup!

What special instructions should be given to a patient with a new AV fistula?

What are the advantages of an AV fistula over a central venous catheter?

  1. Oops! This section is restricted to members. Click here to signup!

No comments yet πŸ˜‰

Leave a Reply