Peritoneal Dialysis

In peritoneal dialysis, the dialysate is infused into the peritoneal cavity through a tube and left there for a specific dwell time to absorb waste products. During this time, waste, chemicals, and excess fluids move from the blood into the dialysate across the peritoneal membrane. After the dwell time, the fluid, now containing waste products, is drained out and discarded. Each cycle of filling and draining the dialysate is known as an "exchange," and it typically occurs 3-5 times throughout the day or overnight using an automated system.

Ultrafiltration in peritoneal dialysis occurs through osmosis. The high concentration of glucose in the dialysis solution creates osmotic pressure, which draws fluid from the blood into the dialysate, resulting in more fluid being drained than initially infused. Although peritoneal dialysis is less efficient than hemodialysis on an hourly basis, the extended duration of treatment means the overall removal of waste, salt, and water is comparable to hemodialysis. Peritoneal dialysis can be performed by patients at home.

Peritoneal Dialysis Complications

Like any medical procedure, peritoneal dialysis may have associated complications, including:

• Risk of infection at the catheter site or within the abdominal cavity.
• Fluid imbalance, which may require adjustment of the dialysis solution concentration.
• Peritoneal membrane changes over time, which can reduce dialysis effectiveness.

Types of Peritoneal Dialysis

There are two primary types of peritoneal dialysis:

• Continuous Ambulatory Peritoneal Dialysis (CAPD): The fluid exchange is done manually several times a day.
• Automated Peritoneal Dialysis (APD): A machine automatically fills and drains the fluid, typically overnight while the patient sleeps.