Hemodialysis is the alternative treatment to peritoneal dialysis. Hemodialysis cleans the blood through an “artificial kidney” or machine. The machine’s computer monitors blood flow, blood pressure, and the quantity of blood removed from the body during treatment. The pump moves the blood from the body, to the dialyzer, and then back to the body. The dialyzer is a plastic tube that acts as a replacement kidney during treatment. Blood enters one side of the dialyzer and the dialysate fluid enters through the other. The blood and dialysate are both separated in the dialyzer by a semi permeable (sponge-like) membrane. The artificial membrane contains many tiny holes that filter the waste products into the dialysate. It also prevents essential blood cells from passing though into the dialysate. The dialyzer works similarly to a tea bag. The tea bag (dialyzer) allows the tea (or waste) to pass through but keeps the tea leaves (or blood products) within the bag. The dialysate fluid helps to pull waste products and excess water from the blood. The dialysate with toxins and extra water then flows to the drain, to be removed by the body and the filtered blood is then returned to your body.
Excess water is removed during dialysis by a process called ultrafiltration. Ultrafiltration occurs when the blood entering the dialyzer is placed under pressure to push excess water through the dialyzer membrane.
Hemodialysis treatment occurs three times a week and usually takes 4-5 hours a week. However, some people may require longer or shorter treatments depending on their needs.