Dialysis is a life-saving treatment for individuals with kidney failure.
Kidney failure is a condition where the kidneys can no longer function adequately on their own.
Dialysis treatment performs the critical functions of filtering waste products, excess fluids, and toxins from the blood.
Learn more about dialysis, including its definition, types, indications, vascular access, and the processes involved in hemodialysis and peritoneal dialysis.
Abdominal transplant surgeons at WashU Medicine
Our transplant surgeons perform hemodialysis access procedures and peritoneal dialysis tube placement procedures in St. Louis for people with kidney disease. For people in need of transplant, we lead a transplant program with a high volume of transplants with excellent results and a multidisciplinary care team.
What is dialysis?
Dialysis is a medical procedure that replicates some of the functions of healthy kidneys when those organs fail. The two main types of dialysis are hemodialysis and peritoneal dialysis.
Understanding kidney failure and kidney disease
Chronic kidney disease (CKD)
Chronic kidney disease is a long-term condition characterized by gradual loss of kidney function over time. It is commonly caused by conditions such as diabetes, hypertension, and chronic glomerulonephritis.
End-stage renal disease (ESRD)
End-stage renal disease is the final stage of chronic kidney disease when the kidneys have lost nearly all their ability to function effectively, requiring dialysis or a kidney transplant.
Acute kidney injury (AKI)
Acute kidney injury is a sudden loss of kidney function, often reversible with appropriate treatment. It can be caused by severe infections, injuries, or exposure to certain drugs or toxins.
Indications for dialysis
Symptoms of kidney failure
- Fluid overload: Swelling in the legs, ankles, and lungs due to fluid retention.
- Electrolyte imbalances: Dangerous levels of potassium or sodium in the blood.
- Uremia: A build-up of waste products in the blood, leading to symptoms such as nausea, vomiting, fatigue, and confusion.
Laboratory parameters
- Glomerular filtration rate (GFR): A GFR below 15 mL/min indicates the need for dialysis.
- Creatinine and blood urea nitrogen (BUN): Elevated levels in the blood signaling impaired kidney function.
Vascular access for hemodialysis
Arteriovenous (AV) fistula
A surgical connection between an artery and a vein, usually in the arm. It provides high blood flow for effective dialysis and has a lower risk of infection compared to other access types.
Requires time to mature (usually several weeks to months) before it can be used for dialysis.
Arteriovenous (AV) graft
A synthetic tube connecting an artery to a vein. It is used when an AV fistula is not feasible.
Can be used sooner than a fistula but has a higher risk of infection and clotting.
Central venous catheter (CVC)
A catheter placed in a large vein, usually in the neck, chest, or groin. It is used for immediate access when dialysis is urgently needed.
Higher risk of infection and other complications; typically a temporary solution.
Hemodialysis
Process of hemodialysis
- Blood removal: Blood is drawn from the body through the vascular access (AV fistula, AV graft, or catheter).
- Filtration: Blood passes through a dialyzer (artificial kidney) composed of thousands of tiny fibers that filter wastes, excess fluids, and electrolytes.
- Cleaned blood: The filtered blood is returned to the body.
Frequency and duration
- Sessions: Typically three times a week.
- Duration: Each session lasts about 3-5 hours.
Setting
- In-center hemodialysis: Performed at a dialysis center under the supervision of healthcare professionals.
- Home hemodialysis: Performed at home after training, offering more flexibility and control over the schedule.
Patient-centered transplant care
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Peritoneal dialysis
Process of peritoneal dialysis
- Catheter insertion: A catheter is surgically placed into the abdomen and used to introduce dialysate (a special fluid) into the peritoneal cavity (the space around the abdominal organs).
- Filtration: The peritoneal membrane acts as a natural filter. Waste products and excess fluids pass from the blood vessels in the peritoneum into the dialysate.
- Drainage: After the filtration process, the used dialysate is drained and replaced with fresh fluid.
Types
- Continuous Ambulatory Peritoneal Dialysis (CAPD): Involves manual exchanges (draining and filling) several times a day.
- Automated Peritoneal Dialysis (APD): Uses a machine (cycler) to perform exchanges automatically, usually while the patient sleeps.
Benefits and challenges of dialysis
Hemodialysis
Benefits
- Efficiency: Effectively removes waste and excess fluid in a controlled setting.
- Monitoring: Performed under the supervision of healthcare professionals.
Challenges
- Time-consuming: Requires frequent visits to a dialysis center.
- Vascular access issues: Risks of infection, clotting, and other complications.
Peritoneal dialysis
Benefits
- Flexibility: Allows more flexibility in scheduling and daily activities.
- Home-based: Can be carried out at home, reducing the need for frequent travel to a dialysis center.
Challenges
- Infection risk: Risk of peritonitis (infection of the peritoneum).
- Catheter care: Requires meticulous care to prevent infections and complications.
Potential risks and complications
Common complications
- Infections: Infection at the catheter site or within the peritoneum (peritonitis for peritoneal dialysis).
- Hypotension: Low blood pressure during or after hemodialysis.
- Electrolyte imbalances: Risk of imbalances in potassium, calcium, and other electrolytes.
Long-term considerations
- Quality of life: Dialysis can impact the patient’s lifestyle, daily activities, and mental well-being.
- Nutritional modifications: Adhering to dietary restrictions to manage fluid and electrolyte balance.
- Regular monitoring: Frequent follow-ups to monitor kidney function, access sites, and overall health.
Support and resources
Patient education
- Training: Comprehensive training for home dialysis (both hemodialysis and peritoneal dialysis) if applicable.
- Diet education: Guidance on dietary modifications to manage fluid and electrolyte balance.
Support groups and counseling
- Support groups: Connecting with others undergoing dialysis for shared experiences and support.
- Counseling: Emotional and psychological support for patients and their families to cope with the challenges of chronic kidney disease and dialysis.
Dialysis is a critical intervention for individuals with kidney failure, offering an essential lifeline for maintaining health and quality of life.
Understanding the different types of dialysis, the processes involved, and the essential aspects of vascular access and long-term care can help patients and their families navigate this complex journey.
