Continuous Ambulatory Peritoneal Dialysis (CAPD)

Related Subjects: |Respiratory Failure |Non invasive ventilation (NIV) |Haemodialysis |Cautions Renal Dialysis and Transplant Patients |Continuous Ambulatory Peritoneal Dialysis (CAPD)

Continuous Ambulatory Peritoneal Dialysis (CAPD) 💧

CAPD is a form of dialysis for kidney failure where the peritoneum acts as a natural semi-permeable membrane to filter waste and excess fluid. It can be done at home and gives patients more independence compared to haemodialysis.

Indications 🩺

• Chronic kidney disease (CKD) stage 4–5 when haemodialysis is unsuitable.
• Patients who prefer home-based or flexible dialysis schedules.
• Difficult vascular access for haemodialysis.
• Children and patients wanting more lifestyle independence.

The CAPD Process 🔄

• Access: A Tenckhoff catheter is surgically placed in the peritoneal cavity.
• Dialysate: Sterile solution (usually glucose-based) is infused into the peritoneal cavity.
• Dwell Time: Fluid remains in place for 4–6 hrs, during which diffusion and osmosis remove urea, creatinine, and water.
• Drainage: Used dialysate is drained and replaced with fresh solution.
• Typical Schedule: 3–5 exchanges daily, each taking 30–40 min.
• Automated PD: Can also be done overnight using a machine (APD).

Complications ⚠️

• Peritonitis 🤢: Abdominal pain, cloudy effluent, fever. Treat with intraperitoneal antibiotics; prevention relies on aseptic technique.
• Catheter problems: Blockage, displacement, infection → may need revision.
• Fluid overload 💦: If ultrafiltration inadequate, use hypertonic dialysate bags.
• Electrolyte imbalance: Regular monitoring required (esp. K⁺, Ca²⁺, phosphate).
• Other: Constipation, pleural effusion, leakage into scrotum, rare sclerosing peritonitis.

Advantages ✅

• Can be done at home or work → promotes independence.
• Gentle, continuous therapy → fewer swings in electrolytes and fluid balance.
• No vascular access needed (avoids fistula/graft complications).

Disadvantages ❌

• High risk of peritonitis and exit-site infection.
• Requires patient motivation, dexterity, and strict asepsis.
• May be less effective in some patients (esp. with adhesions or large body size).

Summary 📝

CAPD uses the patient’s peritoneal membrane as a natural dialysis filter. It provides independence and flexibility but comes with risks of infection and fluid complications. Choice between CAPD and haemodialysis depends on patient suitability, lifestyle, and medical considerations.