During hemodialysis, which substance is primarily removed from the blood?

During hemodialysis, the primary purpose is to remove waste products and excess substances from the blood, particularly those that accumulate in the setting of kidney failure. Urea and creatinine are the key waste products that clinicians aim to reduce through the dialysis process. While sodium can also be removed during dialysis, it is not the primary substance targeted.

The process uses a semipermeable membrane that allows certain small molecules and ions to pass through, while retaining larger blood components like red blood cells and proteins. Sodium, a critical electrolyte, is indeed regulated and can be exchanged during dialysis; however, the focus is more on removing toxins and waste rather than on sodium levels alone.

In this context, even though sodium is removed during hemodialysis, the more significant takeaway is the removal of nitrogenous waste products, particularly urea, which is indicative of the patient’s metabolic state and kidney function. Therefore, while sodium removal is an important aspect, it represents a secondary focus in hemodialysis when compared to the elimination of primary waste products.