Hemodialysis is a process of purifying blood by removing waste products from the kidneys such as creatinine & urea when they are in a state of failure.
Hemodialysis is the most common type of dialysis. This process uses an artificial kidney (hemodialyzer) to remove waste and extra fluid from the blood. The blood is removed from the body and filtered through the artificial kidney. The filtered blood is then returned to the body with the help of a dialysis machine.
Hemodialyzer, or filter, has two parts, one for your blood and one for a washing fluid called dialysate. A thin membrane separates these two parts. Blood cells, protein and other important things remain in your blood because they are too big to pass through the membrane. Smaller waste products in the blood, such as urea, creatinine, potassium and extra fluid pass through the membrane and are washed away.
At the start of a hemodialysis treatment, a dialysis nurse places two needles into your arm that are attached to a soft tube connected to the dialysis machine. The dialysis machine pumps blood through the filter and returns the blood to your body. During the process, the dialysis machine checks your blood pressure and controls how quickly:
- blood flows through the filter
- fluid is removed from your body
Blood enters at one end of the filter and is forced into many, very thin, hollow fibers. As your blood passes through the hollow fibers, dialysis solution passes in the opposite direction on the outside of the fibers. Waste products from your blood moves into the dialysis solution. Filtered blood remains in the hollow fibers and is then returned to your body.
Hemodialysis treatments usually last three to five hours and are performed three times per week. However, hemodialysis treatment can also be completed in shorter, more frequent sessions.
Most hemodialysis treatments are performed at a hospital, doctor’s office, or dialysis center. The length of treatment depends on your body size, the amount of waste in your body, and the current state of your health.