Healthy kidneys clean waste products and extra fluids out of the blood, keep your bones healthy and help to prevent anemia. If kidneys are damaged and fail, treatment is needed to replace these important functions. Dialysis is a treatment that can help replace lost kidney function. There are two main types of dialysis with several possible variations. No one treatment is right for every person so it is important to understand all of the choices and then be able to make an informed treatment decision.
Types of Kidney DIalysis
There are two main types of dialysis used to treat kidney failure, according to the National Kidney Foundation. Hemodialysis (hemo) cleans the blood using a special filter and machine. Peritoneal dialysis (PD) uses the lining of the abdominal cavity, called the peritoneum, to filter the blood. Both types remove waste products, extra salt and fluids from the body.
Hemodialysis
Hemo is the most common type of dialysis, according to the National Institutes of Health. Blood is removed from the body a small amount at a time and run through a special filter called a dialyzer. The dialyzer acts as an artificial kidney to clean the blood which is then returned to the body.
Hemo is often done at special clinics or dialysis centers, where treatments usually last three to five hours and must be done three to four days per week. According to the NIH, hemo can also be done for longer periods of time, more often and are more effective at removing wastes. This type of treatment can be done overnight while a person is sleeping, either in a center or at home. Another option, called short daily dialysis, can be done at home with treatments five to six days per week for two to three hours at a time.
Peritoneal Dialysis
The abdominal cavity is lined with a membrane called the peritoneum. A soft flexible tube is used to place special cleansing fluid, called dialysate, into the abdomen. The membrane acts as a filter and allows waste products and extra fluids to move from the blood into the abdomen. The dialysate is left in the abdomen for four to six hours and then drained and discarded. Each time the abdomen is filled and drained it is called an exchange and the time that the fluid is left in the abdomen is called dwell time. Each exchange takes about 30 minutes and usually needs to be done four times per day. PD done without a machine to control the exchanges is called continuous ambulatory peritoneal dialysis or CAPD. A special machine, a cycler, can be used to fill and drain the abdomen during sleep. This is called continuous cycler-assisted peritoneal dialysis, CCPD, or assisted peritoneal dialysis, APD.
Considerations
Choosing a type of dialysis depends on many factors including how urgently treatment is needed, individual preferences and lifestyle. Hemodialysis can be done at home or a center and requires regular treatments along with diet and fluid restrictions. Peritoneal dialysis is done at home and may provide more flexible treatment schedules, with fewer diet and fluid restrictions. Each type has pros and cons which must be carefully considered. A person may try more than one type in order to find the right fit.
