Certified Nephrology Nurse Certification (CNN) Practice Exam

Phosphate binders are specifically prescribed for patients with chronic kidney disease (CKD) to manage hyperphosphatemia, which is a condition characterized by elevated levels of phosphate in the blood. As kidney function declines in CKD, the ability of the kidneys to excrete phosphate diminishes, leading to an accumulation of phosphate in the body. High phosphate levels can result in various complications, including cardiovascular disease, bone disease, and metastatic calcification.

By using phosphate binders, these medications bind to dietary phosphate in the gastrointestinal tract, reducing its absorption into the bloodstream. This helps to lower serum phosphate levels, mitigating the associated risks. Managing phosphate levels is crucial for maintaining mineral and bone health in CKD patients, thereby preventing potential complications that arise from hyperphosphatemia.

The other choices do not directly pertain to the primary purpose of phosphate binders in the management of CKD. For example, while increasing calcium absorption may be relevant in the context of managing secondary hyperparathyroidism, it is not the primary action of phosphate binders. Enhancing protein synthesis is not a function of these medications, nor do they promote kidney regeneration, which is not typically achievable through pharmacologic intervention in CKD.