Dialysis is a treatment method to remove impurities and excess fluids from the body when the kidneys can no longer provide this vital function. The decision to start dialysis when kidney failure symptoms don't respond to other treatments belongs to the individual in consultation with a physician. The goal of dialysis is to provide stability of chemicals in your body and blood pressure control. Vitamins and minerals are also removed or decreased during the dialysis process.
Function
The use of dialysis mimics the function of the kidneys by using a solution called dialysate and a semi-permeable membrane to filter out wastes and excess fluids from the bloodstream. Dialysis removes blood, in small amounts, from the body, draws it into a machine where its filtered and then returns it to the body. Dialysis treatments may continue over a long period of time for chronic kidney failure. Dialysis uses include cases of acute kidney failure until blood tests reflect the return of kidney function or with poisoning from drugs or toxic substances.
Vitamins
Some vitamins, specifically water-soluble vitamins, are susceptible to removal during dialysis treatments and require replacement through diet and supplements. Vitamin replacement includes thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, cobalamin, folic acid, biotin and vitamin C. The B vitamins along with vitamin C work together with iron to help avoid anemia. Reduced levels of vitamins decreases the ability to ward off infections and diseases. Replacement B and C vitamins are taken after dialysis treatments.
Minerals
Dialysis solution contains minerals that transport across the semi-permeable membrane, equalize in the solution and then return to the body to maintain chemical balance. Blood samples drawn before and during dialysis help indicate which minerals such as sodium, potassium, chloride, phosphorus, magnesium and calcium require adjustment. Small amounts of iron are lost with every dialysis treatment which over time causes iron deficiency anemia if not replaced.
Replacement Treatment
Replacement of vitamins and minerals for kidney failure requires prescription renal vitamin supplements. Kidney failure diets restrict or limit the best food sources of water-soluble vitamins and minerals. Many of these food sources are also potassium-rich foods increasing potassium levels in the blood which the kidneys can't regulate. An additional factor affecting vitamin and mineral consumption includes medications that interfere with the absorption and use of vitamins. Over-the-counter multivitamins include potentially toxic amounts of fat-soluble vitamins such as A, D, E and K and are not recommended.
Considerations
Over-the-counter multivitamins include vitamins unnecessary and potentially toxic for individuals with kidney failure. These vitamins include fat-soluble vitamins A. D, E and K which are stored in the body. Vitamin A, not removed with dailysis, can increase to toxic levels causing elevated triglycerides, anemia and increased calcium levels. OTC multivitamins include the inactive form of vitamin D which relies on kidneys activation to make it usable. If the active form of D is necessary, your nephrologist can provide it. Consult with your physician before taking over-the-counter supplements.
References
- Northwest Kidney Centers: Vitamin and Mineral Concerns in Dialysis
- National Kidney Foundation: Nutrition and Peritoneal Dialysis
- Fresenius Medical Care: Improtant Vitamins and Minerals
- Kidney & Urology Foundation of America: Treatment Methods for Kidney Failure - Hemodialysis
- Rockwell Medical: Dialysis
