When is dialysis needed? What does dialysis do?

Dialysis is a process for removing waste and excess water from the blood, and is used primarily as an artificial replacement for lost kidney function in people withrenal failure. Dialysis may be used for those with an acute disturbance in kidney function (acute kidney injury, previously acute renal failure), or progressive but chronically worsening kidney function – a state known as chronic kidney disease stage.

When is dialysis needed?

You need dialysis when you develop end stage kidney failure – usually by the time you lose about 85 to 90 percent of your kidney function. Haemodialysis (HD) blood taken from the body to be cleaned in a filter known as a dialyser (artificial kidney). A dialyser works on the principle of blood flowing along one side of a semi-permeable membrane made of cellulose or a similar product, with the dialysate flowing along the other side. The dialysate is a fluid with essential minerals and is devoid of toxic products; which comes in close contact with blood separated by a semipermeable membrane. Then there is exchange of substance between the dialysate & the patient’s blood; by way of diffusion, convention & osmosis the “cleaned” blood given back to the patient.

What does dialysis do?

Dialysis is a process of separating out clean blood from unclean blood i/.e, blood with waste, salts & unwanted excess water. The similar process is done by kidney, in normal living. Thus dialysis process regulate the acid base balance in blood & maintains the salt level (sodium & potassium) in the blood.

Types of Dialysis:

In Haemodialysis, an artificial kidney (haemodialyzer) is used to remove waste and unwanted salt and fluid from your blood. To get your blood into the artificial kidney, the doctor needs to make an access (puncture entry) into your blood vessels. Sometimes, an access is made by joining an artery to a vein under your skin to make a bigger blood vessel called a fistula. However, if your blood vessels are not adequate for a fistula, the doctor may use a soft Teflon (or) “rubber” tube to join an artery and a vein under our skin. This is called a graft. Occasionally, an access is made by means of a narrow plastic tube, called a catheter, which is inserted into a large vein in your neck. This type of access may be temporary, but is sometimes used for long-term treatment (Perm-cath).

In Peritoneal Dialysis, your blood is cleaned inside your body. With a small surgical technique, a plastic tube like device called a catheter is placed onto your abdomen (belly). During the treatment, your abdominal (called the peritoneal cavity) is slowly filled with “fluid” through the catheter. The blood stays in the arteries and veins that line your peritoneal cavity. Extra fluid and waste products are drawn out of your blood and into the “inserted fluid”. There is a shift of waste & excess water into the inserted fluid compartment. The fluid later removed from the abdomen & discorded after the exchange occurs in a stipulated time. The peritoneal dialysis can be done in two methods. One manually & other by automated machine.