What is Peritoneal Dialysis and how does it work?

This blog is a fundamental introduction to the Peritoneal Dialysis treatment and will be useful for those who are new to peritoneal dialysis. It will include how it works, who it’s suitable for, and what patients can expect from treatment.

A Fundamental Introduction to Peritoneal Dialysis

Introduction

Peritoneal dialysis (PD) is a lifesaving treatment for patients with kidney failure, myself included. As an alternative to hemodialysis, PD allows for more flexibility, as it can be done at home, and it is a gentler option for patients who cannot tolerate traditional hemodialysis so I am told. It can also be a pain in the ass – cycler drain problems that just won’t go away. Having said that, this blog post aims to provide a fundamental introduction to PD, its mechanisms, suitability for patients, and what to expect during treatment. It is so included because it has been my experience to date the TC Mits (The Common Man in the Streets) really doesn’t have a handle on what PD is all about – nor should they understandably. This blog is for TCMits.

What is Peritoneal Dialysis?

Kidneys are essential organs that filter waste products and excess water from the blood, maintaining a proper balance of minerals and electrolytes (1). When kidneys fail, waste products accumulate in the blood, leading to a dangerous condition known as uremia. Dialysis is a treatment that replicates the kidney’s filtering function and removes these waste products from the blood (2).

Peritoneal dialysis is a type of dialysis that uses the peritoneal membrane, the thin lining of the abdominal cavity, as a natural filter (3). The peritoneal membrane is rich in blood vessels, making it an effective filtration system. During PD, a sterile solution called dialysate is introduced into the peritoneal cavity through a catheter. The dialysate absorbs waste products and excess water from the blood, and is then drained from the body (4).

How Does Peritoneal Dialysis Work?

There are two primary types of peritoneal dialysis: Continuous Ambulatory Peritoneal Dialysis (CAPD) and Automated Peritoneal Dialysis (APD) (5).

1. Continuous Ambulatory Peritoneal Dialysis (CAPD): CAPD is a manual process where the patient drains and refills the dialysate solution multiple times a day, usually four to five times, with each exchange taking about 30 minutes (6). This process is typically done during waking hours, and the dialysate remains in the abdomen for four to six hours before being exchanged (7).
2. Automated Peritoneal Dialysis (APD): APD uses a machine called a cycler to perform the dialysate exchanges (8). The cycler automatically fills and drains the peritoneal cavity with dialysate, usually overnight while the patient sleeps. The number of exchanges and the time spent on the cycler vary depending on individual needs (9).

Who is Suitable for Peritoneal Dialysis?

PD is suitable for a wide range of patients with end-stage renal disease (ESRD). It is particularly appropriate for those who:

• Have difficulty accessing a hemodialysis center due to geographical or transportation limitations (10)
• Are medically stable and can manage the treatment at home (11)
• Prefer a more flexible schedule, as PD can be done at home and does not require strict adherence to a center’s schedule (12)
• Are not suitable candidates for hemodialysis due to medical reasons or personal preference (13)

However, PD may not be suitable for patients with:

• Severe peritoneal scarring or adhesions from previous surgeries or infections (14)
• Limited manual dexterity or visual impairment, as these patients may have difficulty performing the exchanges (15)
• Uncontrolled psychiatric or cognitive disorders that could affect their ability to manage treatment (16)

What to Expect from Peritoneal Dialysis Treatment

1. Preparing for PD: Before starting PD, patients undergo a minor surgical procedure to insert a catheter into the abdomen (17). This procedure is typically done under local anesthesia, and the catheter is left in place for several weeks to heal before PD begins (18).
2. Training: Patients receive training from a specialized PD nurse to learn the proper techniques for managing their treatment, including how to connect and disconnect from the dialysis system, maintaining sterility, and recognizing potential complications (19). The training period usually lasts one to two weeks and may take place in a hospital, clinic, or at home (20).

3. Managing PD at Home: Once trained, patients can perform PD in the comfort of their own homes. It is crucial to maintain a clean environment and follow the prescribed schedule for dialysate exchanges (21). Regular check-ups with the healthcare team are essential to monitor the patient’s health, make necessary adjustments to the treatment plan, and address any issues or concerns (22).
4. Diet and Fluid Intake: As with other dialysis treatments, patients on PD need to follow specific dietary guidelines to ensure their bodies receive the necessary nutrients without overloading on waste products (23). A dietitian will provide personalized advice on dietary restrictions, including limitations on sodium, potassium, and phosphorus intake (24). Fluid intake should also be monitored, as the body’s ability to remove excess fluids is limited (25).
5. Physical Activity: Most patients on PD can engage in regular physical activity, which helps maintain overall health and well-being (26). However, it is essential to consult with the healthcare team before starting any new exercise regimen (27).
6. Potential Complications: While PD is generally safe, complications can arise, including peritonitis (an infection of the peritoneal membrane) and hernias due to increased abdominal pressure (28). Prompt recognition and treatment of these complications are essential to prevent serious health issues (29).

Conclusion

Peritoneal dialysis is a valuable treatment option for patients with kidney failure, offering flexibility and a gentler alternative to traditional hemodialysis. Understanding the mechanics, suitability, and expectations of PD can help patients make informed decisions about their treatment options and better manage their condition. With the proper guidance and support from their healthcare team, patients on PD can maintain their health and enjoy an improved quality of life.

References

1. National Institute of Diabetes and Digestive and Kidney Diseases. (2019). Your Kidneys & How They Work. Retrieved from https://www.niddk.nih.gov/health-information/kidney-disease/kidneys-how-they-work
2. National Kidney Foundation. (2017). Dialysis. Retrieved from https://www.kidney.org/atoz/content/dialysisinfo
3. Jain, A. K., & Blake, P. (2020). Peritoneal Dialysis. In StatPearls. StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK430685/
4. U.S. National Library of Medicine. (2021). Peritoneal Dialysis. MedlinePlus. Retrieved from https://medlineplus.gov/peritonealdialysis.html
5. Nolph, K. D. (2017). Types of Peritoneal Dialysis. UpToDate. Retrieved from https://www.uptodate.com/contents/types-of-peritoneal-dialysis
6. Ibid.
7. Ibid.
8. Ibid.
9. Ibid.
10. Couchoud, C., et al. (2009). Geographical variations in the epidemiology of end-stage renal disease: a French national study. Nephrology Dialysis Transplantation, 24(2), 715-722.
11. Jain, A. K., & Blake, P. (2020). Peritoneal Dialysis. In StatPearls. StatPearls Publishing.
12. National Kidney Foundation. (2017). Dialysis.
13. Ibid.
14. Jain, A. K., & Blake, P. (2020). Peritoneal Dialysis. In StatPearls. StatPearls Publishing.
15. Ibid.
16. Ibid.
17. U.S. National Library of Medicine. (2021). Peritoneal Dialysis. MedlinePlus.

18. Ibid.
19. Figueiredo, A., et al. (2016). Teaching peritoneal dialysis at home: evaluation of a new strategy. Peritoneal Dialysis International, 36(2), 159-166.
20. Ibid.
21. U.S. National Library of Medicine. (2021). Peritoneal Dialysis. MedlinePlus.
22. National Kidney Foundation. (2017). Dialysis.
23. Kidney Care UK. (n.d.). Diet for peritoneal dialysis patients. Retrieved from https://www.kidneycareuk.org/about-kidney-health/living-kidney-disease/kidney-kitchen/diet-for-peritoneal-dialysis-patients/
24. Ibid.
25. Ibid.
26. Heiwe, S., & Jacobson, S. H. (2014). Exercise training in adults with CKD: a systematic review and meta-analysis. American Journal of Kidney Diseases, 64(3), 383-393.
27. Ibid.
28. Jain, A. K., & Blake, P. (2020). Peritoneal Dialysis. In StatPearls. StatPearls Publishing.
29. Ibid.