Lab results are a critical piece of the puzzle when working with a resident on dialysis. Lab values are routinely monitored at the dialysis center to determine if dialysis is “doing its job”. Dialysis works similar to a kidney by cleaning the blood. Dialysis is not able to remove all the extra minerals/nutrients in the body, thus the resident is encouraged to limit foods high in certain minerals. One of these minerals that are often limited is phosphorus. Phosphorus is a mineral found in your bones. It is needed for building healthy strong bones. High phosphorus levels can cause damage to the body. Foods high in phosphorus include dairy products, nuts and seeds, beans and dried peas, dark colas, and processed foods. Some protein items are also high in phosphorus but restriction of these is less important because of the high protein needs of a dialysis resident.
The dialysis dietitian and other team members evaluate the resident’s lab results at least monthly. The dietitian looks closely at phosphorus as well as other minerals and nutrients. Along with these levels the dietitian may also be reviewing the resident’s phosphorus binder therapy or the need for phosphorus binder therapy.
Phosphate binders are generally necessary in combination with limiting high phosphorus foods in the diet to prevent an elevated level. Phosphorus binders work as a “sponge” in the resident’s stomach, but only when food is present to bind with some of the phosphorus in the food and to prevent its accumulation in the blood. It is important that these binders be taken with the meals or snacks in order to be beneficial. Phosphorus in the diet is generally absorbed in the gastrointestinal tract at 60 to 70%, however with the use of binders that level of absorption may be reduced to 30%.
There are different categories of phosphate binders. The nephrologist and the dialysis dietitian determine which type/types of binders are appropriate for the resident based on their mineral/metal containing compounds. Some common binders used today may include Phoslo, Tums, Fosrenol, Renagel, and Renvela. Some residents may use a combination of these to help control phosphorus levels as well as other blood levels in the body. Some residents may take up to as many as 5 or 6 binders with each meal and some with snacks to keep the phosphorus level in control.
Desirable phosphorus levels are possible with monitoring the diet, attending dialysis regularly and taking phosphorus binders as prescribed. So as a healthcare provider it is our challenge to help our residents reach their ultimate phosphorus goal!