Peritoneal Dialysis: Overview of Kidney Treatment via Peritoneum

What is Peritoneal Dialysis?

Peritoneal dialysis removes excess fluid and waste through blood vessels along the internal lining of the abdomen, which is covered by a thin membrane, the peritoneum. Peritoneal dialysis involves putting a soft, hollow tube into the abdominal cavity and filling it with a cleansing fluid, also known as dialysis solution.

The waste and fluid pass from your blood vessels into the peritoneum, where they are diluted in the peritoneal fluid. After a timeframe, the solution and waste drain out, and the overall process of filling and draining your abdomen is called an exchange.

Now, let’s understand how peritoneal dialysis works in a stepwise manner.

How Does Peritoneal Dialysis Work?

Peritoneal dialysis is performed via a catheter placed in the peritoneum. This is the location where old solutions are exchanged for new ones.

Here is a stepwise analysis for the fluid exchange procedure for peritoneal dialysis:

Step 1: Drain

The used-up, saturated solution within the abdomen is drained through the catheter. The solution contains waste products and excess fluid that pass out of the blood vessels.

Step 2: Fill

After draining the old solution from the abdomen, the peritoneal cavity refills with fresh solution through the abdominal catheter.

Step 3: Dwell

When the new solution is emptied into your abdomen, the bags and the catheter tubes are removed. However, only the short tubing with a sterile cap is placed to continue with everyday activities.

Let’s now explore the two major types of peritoneal dialysis.

What are the Types of Peritoneal Dialysis

There are two primary types of peritoneal dialysis: continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD). Both use the peritoneal membrane as a natural filter for fluid and solute exchange. Recent evidences depict that CAPD can achieve a weekly Kt/V of approximately 1.7 with four daily exchanges ¹.

1. Continuous Ambulatory Peritoneal Dialysis (CAPD)

The dialysate fills the abdomen and remains there for the dwell time, then drains. Gravity causes the fluid to move through the catheter and into the abdomen.

• Here are some of the key considerations to remember during a CAPD session:
• There is a requirement for three to five exchanges during the day and one with a longer dwelling time while you sleep.
• The exchange can be done at home, work, or in any dry place.
• Patients are free to engage in any regular activities while cleansing the fluid within their bodies.

2. Continuous Cycling Peritoneal Dialysis (CCPD)

A common name for CCPD is automated peritoneal dialysis (APD), which uses an automated cycler. The machine does the exchanges for you even at night. Moreover, it drains the fluid into a sterile bag, which you can empty in the morning.

Here are some of the core factors associated with CCPD:

• It is essential to keep the machine attached during the day, and it continues the exchange process for you even at night.
• It is not mandatory to connect with the dialysis machine in the early morning; however, you can connect during the day. The exchange may take a day, and it is essential to follow your caregiver’s directions.
• There is a lower risk of peritonitis infection because, in most patients, connecting and disconnecting from the dialysis equipment is less frequent than during a CAPD session.

Note: Consult with your nephrology-focused healthcare professional to select the optimal exchange method for you. Your care team may suggest minor adjustments to tailor the procedure to your needs.

Benefits of Peritoneal Dialysis

Peritoneal dialysis gives you the option to receive treatment in the comfort and convenience. According to a study, patients starting peritoneal dialysis had a 51% lower risk than those starting haemodialysis ².

Here are some of the benefits of peritoneal dialysis that you must know:

• Flexibility: One of the significant advantages of peritoneal dialysis is the flexibility. Unlike other dialysis techniques, patients do not have to maintain a strict schedule and can maintain a normal lifestyle with minimal disruption.
• Improved Quality of Life: Patients undergoing peritoneal dialysis often experience a better quality of life than those on conventional haemodialysis. Peritoneal dialysis avoids the rapid shifts in toxins and fluids, and patients experience symptoms such as nausea and fatigue at lower levels.
• Few Dietary Restrictions: There is a liberal diet chart for peritoneal dialysis, and, as the process is continuous, it closely mimics the function of healthy kidneys.
• Preservation of Kidney Function: Peritoneal dialysis better preserves residual kidney function than haemodialysis. The process drastically enhances the quality of life and may reduce the need for intensive peritoneal dialysis indications.
• Stable for Heart and Blood Vessels: The process is beneficial for the cardiovascular system compared to haemodialysis. The gradual loss of fluid leads to a steady drop in blood pressure, making it a safer option for patients.

Next, let’s explore some of the risks associated with peritoneal dialysis.

Risks of Peritoneal Dialysis

While peritoneal dialysis offers several benefits, it is also essential to evaluate its potential risks. One such example is a study in which 50.8% of patients on peritoneal dialysis experienced at least one infection related to the treatment ³.

Here are some of the peritoneal dialysis complications that you must know before going through the process:

• Adverse Infections: Peritoneal cavity infections are a common complication of peritoneal dialysis. The infection can also begin at the catheter insertion site; therefore, the vascular access site needs to be cleaned regularly. To avoid such infections, it is essential to wash hands and the area where the tube goes inside the body.
• Gain of Weight: Dextrose is a common sugar which is present in the dialysate solution. The absorption of such monosaccharides can lead to an increase in weight. Moreover, such excess calories can also lead to higher blood sugar and diabetes.
• Hernia: Muscles in the abdomen can feel strained when holding fluids for long hours. Moreover, such conditions can also lead to hernia and other chronic kidney diseases.
• Reduced Treatment Efficacy: Peritoneal dialysis may stop working after a few years of continuous administration. You must switch to haemodialysis at this stage to maintain kidney function.

Also read: How to Manage Chronic Kidney Disease: A Guide from Kidney Specialists.