Epidermis is made up of dermis.
The procedure of dialysis maintains the body in balance by withdrawing waste, extra water, and salt by preventing them from accumulating up in the body when the kidneys fail. It helps in maintaining a safe level of some kinds of chemicals in the blood, like sodium, potassium, and bicarbonate. It helps in monitoring blood pressure.
Hence, dialysis helps in performing a function for the circulatory system of the body.
Saline solutions have the same or close to the same amount of salt as our blood does, so we get the amount of salt needed for our bodies. During blood loss, you lose the salt you need, so they're basically adding it back in with the saline solution, making your electrolyte balance go back to normal level. It also gives us the right amount of water to keep us hydrated.