Vascular Access

What Is Vascular Access?

During hemodialysis, the blood is cleaned externally via a machine, and the blood passes through an artificial kidney called a dialyzer. The dialyzer contains many thin fibers that clean the blood and a solution called dialysate filters out excess waste, water, and salt. A vascular access is a connection between the artery and vein that makes hemodialysis possible.

How Does It Work?

Vascular access is used in hemodialysis to remove and return blood. The doctor creates an access to the blood vessel, typically in the arm or the leg. The blood is carried through a tube into the dialyzer, which filters out waste, salt, and extra fluids. Then, the filtered blood is returned to the body through another tube.

This is made possible by three methods: a catheter, an arteriovenous fistula, or an arteriovenous graft.


A venous catheter is a short-term solution for vascular access. A tube is inserted into a vein in the neck, chest, or leg. A catheter works if a patient needs hemodialysis right away, but it is not recommended for long-term use.

Arteriovenous Fistula

An AV Fistula is a long lasting vascular access. A direct connection from the artery to the vein is created by a vascular surgeon. It allows the vein to thicken and expand, allowing easy access for the blood to flow for dialysis.

Arteriovenous Graft

If problems with your veins prevent you from getting an AV Fistula, another long-term solution for vascular access is an AV Graft, which is a looped plastic tube that connects the artery and vein.

How Should I Prepare for Vascular Access?

Some people may feel a slight discomfort during the treatment, but many people do not feel any pain at all. If you feel discomfort, talk to your doctor and they will make you feel as comfortable as possible.

With hemodialysis, patients have to limit their fluid intake, both in drinks and food. While hemodialysis removes excess fluid from the blood, the treatment can only safely remove so much in one session. Getting treatment with too much liquid in your body can give you muscle cramps, a drop in blood pressure and feelings of nausea.

Limit the intake of sodium, potassium, and phosphorus in your diet. Being more conscious of your eating and drinking habits can make a difference in how well the treatments work. Speak with your renal dietician to get expert advice on diet and nutrition.

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