Peritoneal dialysis

Basic principles:

• Utilizes the peritoneal membrane as a semipermeable membrane, therefore avoiding the need for extracorporeal circulation of blood
• The principles are simple:
• A tube is placed into the peritoneal cavity through the anterior abdominal wall
• Diasylate is run into the peritoneal cavity under gravity
• Urea, creatinine, phosphate and other uraemic toxins pass into the diasylate down their concentration gradients
• Water (with solutes) is attracted into the peritoneal cavity by osmosis, depending on the osmolarity of the diasylate (this is determined by the dextrose concentration of the diasylate)
• The fluid is changed regularly to repeat the process

• There are 3 main adaptations of peritoneal dialysis:
• Continual ambulatory peritoneal dialysis (CAPD)
• Nightly intermittent peritoneal dialysis (NIPD)
• Tidal dialysis

Complications:

• Bacterial peritonitis
• Infection around the catheter site
• Constipation
• Pleural effusion (caused leakage of the diasylate through a diaphragmatic defect)