Dialysis, or the artificial system for cleansing the blood, is one of the most common treatment options for patients with end-stage renal disease. There are two main types of dialysis: hemodialysis and peritoneal dialysis. You can learn more about each type of dialysis below:
Dialysis Treatment Options
Hemodialysis is a type of dialysis that uses a special filter to cleanse the blood. During hemodialysis treatment, blood is passed from the body through a set of tubes to a filter. The cleansed blood is then returned to the body through another set of tubes. On average, hemodialysis treatments are typically administered three times per week and last two and a half to four hours.
Hemodialysis treatments are typically performed in an outpatient dialysis center. In order to undergo hemodialysis, an operation may be necessary to connect an artery and a vein in one of the limbs (called arteriovenous fistula or graft) because this type of dialysis cannot be performed without a fistula, graft or catheter.
How Hemodialysis Works
Hemodialysis replaces the work of your own kidneys to clear wastes and extra fluid from your blood. This is done using a special filter called a dialyzer or artificial kidney. Your blood travels through plastic tubing to the dialyzer, where it is cleaned and then returned to you. At the beginning of each treatment, two needles are placed into your access. These needles are connected to the plastic tubing that carries your blood to the dialyzer. Only a small amount of blood is out of your body at any one time. The dialysis machine pumps your blood through the dialysis system and controls the treatment time, temperature, fluid removal and pressure. This basic process is the same for home hemodialysis, except that you and a care partner are trained to do your treatment at home.
Hemodialysis at Home or In-Center
You can do hemodialysis at a dialysis center where a nurse or technician performs the tasks required during treatment. In-center hemodialysis is usually done three times a week for about three to four hours or longer each session. In-center treatments are done at a pre-scheduled time.
You can also do hemodialysis at home where you are the one doing your treatment. At home, you may be better able to fit your treatments into your daily schedule. Studies show that the more you know about your treatment and the more you do on your own, the better you are likely to do on dialysis.
Peritoneal Dialysis (PD) is a process in which blood is artificially cleansed using a man-made solution that is delivered into and removed from the abdominal cavity. Peritoneal Dialysis does not completely compensate for all normal kidney functions. For example, it does not replace the hormones produced by the normal kidney.
In PD, the peritoneal cavity in the abdomen is used as a reservoir for the dialysis solution. The thin membrane lining this cavity provides a suitable barrier through which blood can be filtered. A tube or catheter is surgically placed in the abdomen to create an access for peritoneal dialysis.
In Peritoneal Dialysis, a sterile solution containing minerals and glucose is run through a tube into the peritoneal cavity, where the peritoneal membrane acts as a semipermeable membrane. The dialysate (1-3 L of prescribed solution) is left in the peritoneal cavity for a period of time to absorb waste products, and then it is drained out through the tube and discarded. This cycle is repeated 4-5 times during the day. Peritoneal dialysis treatment is used at home under the routine supervision of a dialysis facility. The types of chronic peritoneal dialysis are determined by various schedules:
CAPD- CAPD is a manual form of peritoneal dialysis, with no machine. During CAPD, the dialysate solution stays in the peritoneal cavity for about 4 to 6 hours. After this time, the solution is drained out of the cavity. The cavity is then is then refilled with fresh solution. This is the most commonly used form of peritoneal dialysis and employs 4-6 exchanges per day.
CCPD, also known as Automated Peritoneal Dialysis (APD), is a form of peritoneal dialysis using a cycler at night. During CCPD, a machine automatically fills and drains the dialysate from the peritoneal cavity. This process takes about 10 to 12 hours; therefore CCPD is performed at night. The cycler automatically makes 4-6 exchanges per day.
Nocturnal Intermitted Peritoneal Dialysis or IPD is much like CCPD but is usually performed in a hospital. Treatment sessions may last up to 24 hours, have an increased number of exchanges (5-8) at night and may be done several times a week. With IPD, the abdomen is drained and left "dry" (without dialysate) during the day. IPD is rarely done anymore.