When a renal diet is ordered, just what does this mean? In long term care, the restrictions are liberalized. The diet may be interpreted as general (or regular), no added salt with a limit of 1 cup/day, high protein, low potassium which means no oranges, orange juice, bananas, tomato/prune juice or baked potato. Also, a fluid restriction is usually ordered.
A diabetic diet may be warranted if the resident has a history of diabetes. This may be a low concentrated sweet diet or consistent carbohydrate according to your facility diet manual. The resident may need to have a consistency change such as mechanical soft or pureed. Other individual restrictions may be added such as lactose restricted.
No added salt is a liberalized low salt diet. This excludes only a salt packet from the tray. If the facility has salt shakers on the table, education is needed to discourage its use. The resident does, however, have the right to use it as desired. A salt restriction helps with compliance to a fluid restriction. Salt increases thirst and can lead to drinking excess fluid, which can cause problems. When the kidneys are malfunctioning, they cannot get rid of excess sodium as efficiently. This can lead to swelling, high blood pressure, and further damage to the kidneys.
A milk limit is necessary due to the high content of phosphorus. Some dialysis centers limit to 1/2 cup milk per day. Your facility dietitian will be in communication with your local dialysis dietitian to determine this. When kidney function declines, the body has a difficult time keeping phosphorus and calcium in balance. Both are needed for good bone function. When phosphorus levels increase, calcium levels decrease. The body will then try to take calcium from the bones making them weak. High levels of phosphorus are also found in cola drinks, peanut butter, cheese, sardines, chicken/beef liver, nuts, caramels, beer and ice cream. Usually, medications such as PhosLo or Renvela are given to help block phosphorus absorption. These must be taken with meals to be effective.
A high protein diet is needed because when dialysis is done, albumin is pulled out of the blood stream. Albumin helps to maintain growth and tissue repair. During dialysis, albumin in the blood helps with fluid removal. It helps “pull” extra fluid from swollen tissues back into the blood where it can then be removed. The only way to replace the lost albumin is by eating more protein. High protein foods include meat, fish, poultry, and eggs. Watch the consumption of nuts, legumes, and dairy products due to phosphorus. High protein supplements may be necessary to achieve adequate albumin levels in the blood. Dialysis centers usually have their own normal for albumin but most of the time a level of 4.0 gm/dL is desired. When a person is overweight or obese, lower calorie high protein supplements are available. A high protein diet may also be achieved by allowing the dietitian to recommend adding extra protein with meals, especially with breakfast.
A low potassium diet restriction may also be ordered. The abbreviation for potassium is K+, not to be confused with vitamin K. Diseased kidneys are often unable to remove excess potassium from the blood. When blood potassium levels become too high, this may cause the heart to beat irregularly or even stop without warning. Potassium also helps in fluid and electrolyte balance and maintaining pH levels. In long-term care, low potassium is generally liberalized. Mostly fruits and vegetables are high in potassium, but there are other foods such as milk, yogurt, ice cream, and chocolate that are high. Baked potatoes are limited as the majority of potassium is just under the skin. Some diets will exclude or limit potatoes altogether or specify that they be leached (a tedious and long process of peeling, rinsing, and soaking).
Remember, each resident is an individual and may or may not need some or all of the above restrictions. The restrictions discussed in this article are mainly for those on 3-day/week hemodialysis. Those on in-house or peritoneal dialysis may have very few of these restrictions. Some physicians will liberalize renal diets if the resident is eating poorly or in an end of life situation. Pre-dialysis diets, or chronic kidney disease stage 4, may need a low protein diet. Quite often they are nauseated from high blood levels of toxic elements and may not be eating well and are therefore self limiting. There are many factors to consider with a renal diet. The best resource available is your facility dietitian to help decipher the most effective diet.