Wellness Library

Image of dialyzer Hemodialysis

Hemodialysis is one kind of dialysis. It uses a machine that holds a filter called a dialyzer. As blood flows through the dialyzer, waste is removed and fluid and chemicals are balanced. Hemodialysis treatments are usually done at a special dialysis center. In some cases, treatments may be done at home.

How Hemodialysis Is Done

Two needles are inserted into a blood vessel (called an access), usually in your arm. Each needle is attached to a tube. One tube carries your blood into the dialyzer, where it is cleaned. Clean blood returns to your body through a second tube and needle.

Problems to Watch For

Call your nurse or dialysis technician if you have any of these symptoms during or after treatment:

  • Chest pain

  • Bleeding from the needle site

  • Shortness of breath

  • Fever or chills

  • Headache or lightheadedness

  • Nausea or vomiting

  • Itching

  • Muscle cramps

Your Experience

  • Hemodialysis usually takes about 3-5 hours. It is usually done 3 times a week.

  • You’ll have a regular schedule for your hemodialysis. Many centers have evening and weekend hours as well as weekday hours to help you continue working.

  • A trained nurse or technician connects you to the dialysis machine. He or she watches for problems and makes sure you are comfortable.

  • During treatment, only a small amount of blood (about 1 cup) is out of your body at any one time.

  • During or after your first few treatments, you may have a headache, muscle cramps, or feel nauseated. These should decrease as your body gets used to the treatments.