Hemodialysis cleans and filters your blood using a machine to temporarily rid your body of harmful wastes, extra salt, and extra water Hemodialysis helps control blood pressure and helps your body keep the proper balance of important chemicals such as potassium, sodium, calcium, and bicarbonate Dialysis can replace part of the function of your kidneys Diet, medications, and fluid limits are often needed as well Your diet, fluids, and the number of medications you need will depend on which treatment you choose.