How does Peritoneal Dialysis work?

  • Peritoneal dialysis (PD) uses the peritoneal membrane as a filter for the blood. The peritoneal cavity is the space in the abdomen that is lined by the peritoneal membrane.
    Example of a standard PD catheter.
    Catheter type and placement will vary by patient.
  • Fluid (called dialysate or PD solution) is put into the peritoneal cavity through a small, flexible tube called a peritoneal catheter (or PD access). The catheter is about the size of a straw and is placed in the lower abdomen or pre-sternally.
    • The catheter is typically ready to use in about 2 weeks and completely healed in about 4 weeks. 
    • The clinic nurse teaches how to care for the PD access to prevent infection
    • The catheter is covered up by clothing when not in use. 
  • The dialysate remains in the peritoneal cavity for the prescribed time. During this time, waste products and extra water move from the blood, through the peritoneal membrane, and into the dialysate in the peritoneal cavity.
  • The used dialysate is then drained and replaced with new dialysate.

Steps for PD

  • The PD catheter is connected to sterile tubing, which connects to a drain bag and new bag of dialysate. Each set of fill, dwell, and drain is called an exchange.
    • Fill - New dialysate flows into the peritoneal cavity.
    • Dwell - The new dialysate stays, or dwells in the peritoneal cavity for a period of time.  This is when dialysis is taking place - extra water and waste products are removed from the blood.
    • Drain - Used dialysate is drained out of the peritoneal cavity into the empty drain bag. This fluid contains the extra water and waste products that were removed from the blood.


Steps to PD (Fill, Drain, Dwell)

PD Modalities

  • There are two PD modalities: continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD).  The choice can depend on lifestyle, personal likes, dislikes, and clinical needs as determined by physicians. The healthcare team will work with the patient to help decide which modality will work best.
  • Both CAPD and APD are self-care treatments, meaning that the patient will manage their treatments and care at home, with the support of their healthcare team.
  • PD may offer the following health and quality of life benefits:
    • Preservation of residual renal function1-3
    • Better energy and stamina4-7 compared to 3 times per week in-center hemodialysis (ICHD), patients report being more active and independent
    • More likely to receive a transplant10
    • Increased control2 – more daytime hours for work, school, family, friends, and hobbies
    • Greater quality of life scores compared to standard ICHD7, 11-12
    • Ability to travel
    • Schedule flexibility


Continuous Ambulatory Peritoneal Dialysis

CAPD Image
  • CAPD is a manual form of PD. Most people start with 4-6 exchanges during a 24 hour period. The exchanges are usually done in the morning after waking, around lunch, around suppertime, and just before bedtime. At night, most people leave the fluid in their abdomen while they sleep, but do not wake up to do more exchanges.
  • Each drain and fill takes about 30 - 45 minutes to complete, but the time can vary. During the 4 to 6 hours between exchanges, the patient is free to do their normal activities. They are not connected to any tubing during dwell, but dialysate is always in the peritoneal cavity.


Automated Peritoneal Dialysis

APD Image
  • APD is a form of PD done with a machine called a cycler. The cycler will automatically drain and fill dialysate from the peritoneal cavity.
  • Most of the exchanges are done while the patient sleeps. Generally, people are connected to the cycler for 8 to 10 hours each night.13-14
  • Depending on the prescribed therapy, some patients may require a last fill prior to disconnecting from the cycler in the morning. Others may need one or more exchanges during the day, performed manually or by reconnecting to the cycler for their drain and fill, then disconnecting to continue with their day.
  • A standard 3-prong outlet is required to use the cycler.

magnifying glass     Things to Consider About PD

  • PD is a self-care treatment, done at home
  • There is flexibility for treatment times
  • Treatments need to be done every day
  • The treatments are gentle - most people have no discomfort 
  • Diet may be more flexible compared to other therapies
  • An infection called peritonitis may occur with some people
  • The patient can do their usual activities while the dialysis is taking place
  • Visits to the clinic are required every 4 – 6 weeks to meet with the doctor and healthcare team to check laboratory values and see how the treatments are going


Risk Icon     Peritoneal Dialysis Risk

The reported benefits of peritoneal dialysis may not be experienced by all patients.

Peritoneal Dialysis does involve some risks that may be related to the patient, center, or equipment. These include, but are not limited to, infectious complications and achievement of adequacy (depending on patient characteristics and comorbidities). Examples of infectious complications include peritonitis, and exit site and tunnel infections. Non-infectious complications include catheter complications such as migration and obstruction, peritoneal leaks, constipation, hemoperitoneum, hydrothorax, increased intraperitoneal volume, respiratory, and gastric issues. It is important for healthcare providers to monitor patient prescriptions and achievement of adequacy and fluid management goals. Patients should adhere to dietary restrictions and dialysis prescription.

Patients should consult their doctor to understand the risks and responsibilities of performing peritoneal dialysis.


Home Icon     Training to do PD at Home

  • PD clinic nurses teach patients (and care partners) how to do PD and to troubleshoot
  • The training times vary and are customized to meet individual needs and be sure the patient is ready to do PD at home.  If the patient is not able to do their own treatments, a care partner can be trained to do the treatments. At the end of the training, the patient will begin doing their treatments at home.
  • Will learn how to operate dialysis equipment, monitor vital signs, administer PD treatment, troubleshoot, and handle emergency situations. 
  • Requires a clean space to do treatments at home. Supplies are typically delivered monthly, and need to be kept in a clean, dry area.



  1. Wang, A.Y.-M., and K.-N. Lai. “The Importance of Residual Renal Function in Dialysis Patients.”   Kidney International 69, no. 10 (2006): 1726–32.

  2. Maddux, Dugan W., Len A. Usvyat, Thomas Blanchard, Yue Jiao, Peter Kotanko, Frank M. Van Der Sande, Jeroen P. Kooman, and Franklin W. Maddux. “Transition Period Clinical Trajectories for PD versus HD Starters.” Peritoneal Dialysis International 39, no. 1 (2018): 42–50.

  3. François K, Bargman J. “Evaluating the Benefits of Home-Based Peritoneal Dialysis.” International Journal of Nephrology and Renovascular Disease, 7 (2014): 447.

  4. Ramer SJ, McCall NN, Robinson-Cohen C, et al. “Health Outcome Priorities of Older Adults with Advanced CKD and Concordance with Their Nephrology Providers’ Perceptions.” Journal of the American Society of Nephrology 29, no. 12 (2018): 2870–78.

  5. Ghani Z, Rydell H, Jarl J. “The Effect of Peritoneal Dialysis on Labor Market Outcomes Compared with Institutional Hemodialysis.” Peritoneal Dialysis International 39, no. 1 (2018): 59–65.

  6. Tokgoz B. “Clinical Advantages of Peritoneal Dialysis.” Peritoneal Dialysis International 29, Suppl 2 (2009): S59–61.

  7. Barendse SM, Speight J, Bradley C. “The Renal Treatment Satisfaction Questionnaire (RTSQ): A measure of satisfaction with treatment for chronic kidney failure.” American Journal of Kidney Diseases 45, no. 3 (2005): 572–579.

  8. Sinnakirouchenan R, Holley JL. “Peritoneal Dialysis Versus Hemodialysis: Risks, Benefits, and Access Issues.” Advances in Chronic Kidney Disease 18, no. 6 (2011): 428–32.

  9. Manera KE, Johnson DW, Craig JC, et al. “Patient and Caregiver Priorities for Outcomes in Peritoneal Dialysis.” Clinical Journal of the American Society of Nephrology 14, no. 1 (2018): 74–83.

  10. Snyder JJ, Kasiske BL, Gilbertson DT, Collins AJ. “A Comparison of Transplant Outcomes in Peritoneal and Hemodialysis Patients.” Kidney International 62, no. 4 (2002): 1423–30.

  11. Rubin HR, Fink NE, Plantinga LC, et al. “Patient Ratings of Dialysis Care with Peritoneal Dialysis vs Hemodialysis.” JAMA 291, no. 6 (2004): 697–703.

  12. Juergensen E, Wuerth D, Finkelstein SH, et al. “Hemodialysis and Peritoneal Dialysis: Patients’ Assessment of Their Satisfaction with Therapy and the Impact of the Therapy on Their Lives.” Clinical Journal of the American Society of Nephrology 1, no. 6 (2006): 1191–

  13. Heimbürger O, Blake PG. Apparatus for Peritoneal Dialysis. In: Daugirdas JT, Blake PG, Ing TS, eds. Handbook of Dialysis. 5th ed. Philadelphia, PA: Walters Kluwer Health; 2015:408-424.

  14. K/DOQI Clinical practice guidelines for peritoneal dialysis adequacy. Am J Kidney Dis. 2006;48 Suppl 1:S91-S129. Available from:



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