What is Dialysis Access Contrast Venography?

Contrast venography (also called a venogram or catheter-based vein mapping) is a specialized X-ray procedure that uses a contrast dye injected into a vein to create detailed images of the veins in your arm and upper chest.

It is commonly performed before creating a permanent dialysis access (arteriovenous fistula or graft) or to evaluate problems in an existing fistula or graft. The images help the care team see the size, shape, and pathway of the veins, including any narrowings, blockages, or anatomic variations.

Why Do I Need This Procedure?

Your provider may recommend contrast venography for dialysis access planning or evaluation when:

• Ultrasound vein mapping is not sufficient or shows limited options
• There is concern for central vein stenosis or prior catheter use
• Planning the best site for a new arteriovenous fistula or graft
• Evaluating reduced flow, swelling, or other problems in an existing dialysis access
• The information helps maximize the chance of successful, long-lasting dialysis access

How Do I Prepare for the Procedure?

Preparation is usually straightforward:

• Medications: Tell your team about all medications, especially blood thinners (warfarin, apixaban, etc.). You may be asked to hold some of them.
• Allergies: Report any prior reaction to iodinated contrast (X-ray dye), shellfish, or iodine.
• Kidney function: If you still have residual kidney function, the team will discuss the contrast load and possible alternatives (such as CO₂ venography).
• Eating/drinking: You may be asked to have only clear liquids for a few hours before the procedure.
• Clothing & arrival: Wear loose, comfortable clothing. Leave jewelry at home. Bring a list of your medications.

What is the Procedure?

The procedure is performed by an interventional radiologist or trained specialist in a sterile procedure room:

• You will lie on an X-ray table. Monitors track your vital signs.
• The skin over a vein in the arm (or the fistula/graft if evaluating existing access) is cleaned and numbed with local anesthetic.
• A small needle is inserted into the vein, followed by a thin catheter if needed.
• Contrast dye is injected while X-ray images (digital subtraction venography) are taken as the dye travels through the veins toward the heart.
• The images show vessel size, pathway, and any narrowings or blockages.
• The procedure usually takes 20–45 minutes. You may feel mild pressure or a warm sensation when the dye is injected.

How Do I Care for the Access Point Afterward?

Care focuses on the puncture site:

• Pressure is applied to the puncture site after the catheter is removed to stop any bleeding.
• A small bandage is placed over the site. Keep it clean and dry for the first 24 hours.
• Avoid heavy lifting or strenuous activity with that arm for 24 hours.
• You may shower the next day; gently pat the area dry.
• Mild bruising or tenderness at the puncture site is common and usually resolves in a few days.

What Do I Look Out For?

Contact your care team promptly if you notice any of the following:

• Increasing pain, swelling, or redness at the puncture site
• Bleeding that does not stop with gentle pressure
• Fever, chills, or feeling unwell
• Significant swelling of the arm, hand, or face on the same side
• Numbness, tingling, or color changes in the hand or fingers
• Signs of allergic reaction (rash, difficulty breathing, swelling of the face or throat) — seek emergency care