Types of peritoneal dialysis

Continuous Ambulatory Peritoneal Dialysis (CAPD)

CAPD is performed manually. It can be done almost anywhere. CAPD stands for:

Continuous. CAPD is a continuous process. The blood is being cleaned as long as fresh dialysis fluid is exchanged for old fluid in the peritoneal cavity. With CAPD, dialysis takes place 24 hours a day, 7 days a week.
Ambulatory. To ambulate means to walk. CAPD patients are not attached to a machine for treatment, but move around freely and even dialyze while sleeping.
Peritoneal. The peritoneum is the membrane in the abdomen that is used as the dialysis membrane. The peritoneal membrane acts as a filter, removing waste and excess fluid from the blood. The wastes and excess fluid cross the membrane into the dialysis solution. They are removed from the body when the dialysis solution is drained into a drainage bag.
Dialysis. The blood inside the body is filtered and cleansed of wastes and excess water.

How does a CAPD exchange work?

An exchange of dialysis fluid in CAPD is simple. You will be able to do it yourself once you have been trained by a specialized PD nurse. This training usually takes place at the renal center and the duration will depend on the hospital you are with.

The basic steps are:

Connect the peritoneal dialysis catheter to a disposable tubing and bag set of dialysate fluid and an empty drain bag.
Drain the fluid from your peritoneal cavity into the drain bag (Approximately 20 minutes).
Drain fresh fluid into your peritoneal cavity by clamping the drain bag, opening the inflow of the new dialysate bag, and letting the fluid fill your peritoneal cavity (Approximately 10 minutes).
When the new fill bag is empty, clamp the bag and disconnect.
Discard the used solution and disposable tubing set.
Go about your activities with the solution in your peritoneal cavity until the next exchange (about 4 to 6 hours).

An exchange takes about 30 minutes. Most CAPD patients need to do between three and five exchanges a day.

Automated peritoneal dialysis (APD)

Automated peritoneal dialysis (APD) is peritoneal dialysis using a small machine. It is done at night while you are sleeping.

The APD machine automatically controls the timing of exchanges, drains the used solution, and fills the peritoneal cavity with new solution. Patients need to keep fluid in their peritoneal cavity during the day. Some need to perform an additional exchange during the day to ensure they receive sufficient dialysis.

How does APD work?

Before the patient goes to bed, they connect their PD catheter to the APD machine, and switch on the machine.
The APD machine carries out exchanges automatically overnight while the patient is asleep. The machine carefully measures the amount of fluid that goes into the peritoneal cavity and the amount that comes out. This usually continues for between 8 to 10 hours.
In the morning, the patient disconnects from the machine.
Usually the patient will have a last fill that will remain in the peritoneal cavity throughout the day.

At the renal_center, a training nurse will teach you to perform your CAPD or APD treatment safely. At home, most patients or their caregivers, do the treatments. Patients return to the renal center for regular check-ups.

Patients on either kind of peritoneal dialysis are relatively independent and can manage their own care at home. Continuous dialysis means dialysis is usually happening 24 hours a day and 7 days a week, with no days off. This means that the dialysis is effective, provides good control of blood pressure, and offers more choices of diet and fluid intake than Haemodialysis. PD patients are usually comfortable and pain free. Most adults hold 2 to 3 liters of fluid in their abdomen without being aware of it. No needles are used for PD. Although PD patients do not have to travel to the renal center for treatment sessions, it is important to maintain the dialysis schedule of 3-5 exchanges each day prescribed by your doctor.

Travel for business or pleasure can be arranged easily with a little planning.

PD requires the insertion of a permanent catheter, which poses some risk of infection.

Storage space is needed at home for PD supplies. The bags of dialysis fluid come in boxes of different quantities depending on your type of PD requirements, so a month's supply can be as many as 30 boxes. These must be stored in a clean, dry area.

May 1, 2006

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