One of the most difficult aspects of being on dialysis is the fluid restriction. Often, being on dialysis means you do not urinate as much as you used to, or you might not urinate at all. Besides ‘cleaning’ our blood, our kidneys also remove the extra fluid/water we eat and drink in a day.

When working properly, your kidneys filter 180 liters of blood daily. Our entire body’s blood supply is filtered approximately 20-25 times per day. During filtration, you create 1 to 2 liters of urine every day.

What is a fluid?

One of the difficult parts of dialysis is knowing ‘what is a fluid?’. This sounds simple, but more things are considered fluid than just what we drink. A fluid is ANYTHING that is liquid at room temperature.

For example:

  • Water, soda, tea, coffee, milk, non-dairy milk, and all other beverages
  • Ice
  • Soups and stews
  • Ice cream, sherbet, sorbet, popsicles, etc.
  • Jell-O® / Gelatin
  • Pudding
  • Protein drinks like Nepro, Novasource, Ensure, etc.

Some watery fruits such as watermelon and grapes are not counted towards your daily fluid amount, but you should limit your daily servings if you have fluid restrictions.

Fluid and stages of CKD

Depending on your stage of chronic kidney disease (CKD), you may have different fluid recommendations.

CKD stages 1-2

When you have chronic kidney disease stage 1-2, it is important to drink enough water: around 64 oz., or eight 8 oz. glasses every day. This will help keep your kidneys well hydrated and working well.

CKD stages 3, 4, and 5 (non-dialysis)

Once you reach the later stages of CKD – stages 3, 4, and 5 non-dialysis–you might need to limit your total fluid intake. This will be something you and your nephrologist (kidney doctor) should discuss.

It is possible during these stages that you could experience fluid retention (having too much fluid buildup in your body).

Alert your doctor right away if you notice these signs of possible fluid retention:

  • Swelling in your feet and ankles
  • Difficulty or shortness of breath when walking short distances like 1 – 3 blocks
  • Difficulty or shortness of breath while walking up 1 flight of stairs
  • Difficulty or shortness of breath when lying flat on your back. You might need 1 or more extra pillows to help you breathe

CKD stage 5 (dialysis)

Once you are on dialysis you will need to limit how much fluid you drink in a day. The recommended amount is 32 oz. per day of total fluid. If you still urinate, you can have a little more: 32 oz. per day plus the volume equal to the amount you urinate in 24 hours.

For example: If you urinate 1 cup (8 oz.) in a day, you could have 32 oz. + 8 oz. = 40 oz. of fluid daily.

Your daily urine output may decrease over time. It is suggested that you measure your urine output one day every three months and share that information with both your nephrologist and dialysis dietitian. Some people collect their urine in a 20 oz. disposable beverage cup, like you find at a convenience store. Before you get started, mark your container in ½ cup increments. After a 24-hour urine collection, record how much urine you produce, and throw away the disposable cup.

Having extra fluid in your body is dangerous because it results in an increase in blood volume. When the kidneys cannot handle this extra volume of blood, you may experience complications such as:

  • Swelling (edema)
  • Poor nutritional status
  • High blood pressure
  • Lung infections like pneumonia
  • Heart failure
  • Shortness of breath
  • Decreased blood proteins
  • Keeping blood protein levels at the right level makes your dialysis treatment most effective.