Dialysis

Overview

Dialysis is a treatment for individuals with kidney failure, where the kidneys can no longer effectively filter blood. This leads to the accumulation of wastes and toxins in the bloodstream. Dialysis steps in to perform the function of the kidneys by removing these waste products and excess fluids from the blood.

Reasons for undergoing the procedure

Kidney failure, or end-stage renal disease (ESRD), often necessitates dialysis and can result from conditions like high blood pressure, diabetes, lupus, or injuries. Some people develop kidney problems without a known cause. Kidney failure can be chronic or acute, the latter potentially reversible after a severe illness or injury. In stage 5 kidney disease, considered ESRD, kidneys function at only 10% to 15% of their capacity, requiring dialysis or a kidney transplant for survival, with some patients undergoing dialysis while awaiting a transplant.

The kidneys, part of the urinary system, are two bean-shaped organs located below the ribcage on either side of the spine. They filter toxins from the blood, returning nutrient-rich blood to the body and creating urine from waste and excess water. Additionally, the kidneys play a crucial role in regulating blood pressure.

Risks

Hemodialysis risks

  • AV fistula or graft issues:
    • Infection: There is a risk of infection at the site of the fistula or graft, which can lead to serious complications if not treated promptly.
    • Poor blood flow: Blood flow through the fistula or graft may be inadequate, which can affect the efficiency of the dialysis.
    • Blockage: Scar tissue or blood clots can form, causing a blockage in the fistula or graft. This may require medical intervention to restore proper function.
  • Blood leak detection:
    • Needle or tube dislodgement: Although rare, the dialysis needle can come out of the arm, or a tube can come out of the machine during dialysis.
    • Safety systems: A blood leak detection system alerts patients and medical staff to this issue. The machine temporarily shuts off to prevent blood loss until the problem is resolved.

Peritoneal dialysis risks

  • Catheter-related issues:
    • Skin infections: There is a risk of developing skin infections around the catheter insertion site, necessitating careful hygiene and monitoring.
    • Peritonitis: Bacteria can enter the abdomen through the catheter, causing peritonitis. Symptoms include fever, abdominal pain, nausea, and vomiting.
  • Abdominal muscle weakness:
    • Hernias: The use of an abdominal catheter and the process of filling the abdomen with fluid can weaken abdominal muscles over time, leading to hernias. This condition occurs when an organ, such as the small intestine, pushes through the weakened abdominal muscles, creating a bulge near the belly button or in the groin area. Surgery may be required to repair the hernia.
  • Weight gain:
    • Dextrose absorption: The body absorbs dextrose (a sugar) from the dialysis solution during peritoneal dialysis. Over time, this can lead to weight gain, so patients need to monitor their diet and exercise regularly.

Types of dialysis

Dialysis methods: hemodialysis and peritoneal dialysis
Hemodialysis
Hemodialysis is a process where a machine removes blood from your body, filters it through a dialyzer (artificial kidney), and then returns the cleaned blood to your body. This process typically lasts 3 to 5 hours and is performed three times a week either in a hospital or a dialysis center.

Peritoneal dialysis
Peritoneal dialysis involves using the tiny blood vessels inside the abdominal lining (peritoneum) to filter blood with the help of a dialysis solution. This solution is a cleansing liquid that contains water, salt, and other additives.

Peritoneal dialysis is always performed at home and can be done in two ways:

  • Automated peritoneal dialysis: Uses a machine called a cycler.
  • Continuous ambulatory peritoneal dialysis (CAPD): Is done manually.

Before the procedure

Hemodialysis preparation
Before starting hemodialysis, you’ll undergo a minor surgical procedure to facilitate access to your bloodstream. There are two main options:

  • Arteriovenous fistula (AV fistula): A surgeon connects an artery and a vein in your arm, creating a connection that enlarges the vessels, making dialysis access easier and improving blood flow.
  • Arteriovenous graft (AV graft): If your artery and vein are too short to connect directly, the surgeon uses a graft (a soft, hollow tube) to join them. This also enlarges the vessels and improves blood flow for dialysis.
    If dialysis needs to be initiated quickly, a catheter (a thin tube) may be placed in a vein in your neck, chest, or leg for temporary access. Your healthcare provider will instruct you on how to prevent infections in your fistula or graft and will also guide you if you choose to perform hemodialysis at home.

Peritoneal dialysis preparation
About three weeks before starting peritoneal dialysis, you will undergo a minor surgical procedure where a surgeon inserts a soft, thin tube (catheter) through your abdomen into the peritoneum. This catheter remains in place permanently.

A healthcare provider will teach you how to perform peritoneal dialysis at home and how to prevent infections at the catheter site.

During the procedure

Hemodialysis
During hemodialysis, the dialysis machine:

  • Removes blood from a needle in your arm.
  • Circulates the blood through the dialyzer filter, which moves waste into a dialysis solution. This cleansing liquid contains water, salt, and other additives.
  • Returns filtered blood to your body through a different needle in your arm.
  • Monitors your blood pressure to adjust how fast blood flows in and out of your body.

Peritoneal dialysis
During peritoneal dialysis, you:

  • Connect the catheter to one branch of a Y-shaped tube. This tube connects to a bag that has dialysis solution. The solution flows through the tube and catheter into the peritoneal cavity.
  • Disconnect the tube and catheter after about 10 minutes, when the bag is empty.
  • Cap off the catheter.
  • Go about your usual activities while the dialysis solution inside the peritoneal cavity absorbs waste and extra fluids from the body. This process can take 60 to 90 minutes.
  • Remove the cap from the catheter and use the other branch of the Y-shaped tube to drain the fluid into a clean, empty bag.
  • Repeat these steps up to four times a day. You sleep with the solution in your stomach all night.

Some people prefer to do peritoneal dialysis at night. With automated peritoneal dialysis, a machine called a cycler pumps the fluid in and out of the body while you sleep.

After the procedure

After hemodialysis
Some people experience low blood pressure during or immediately after hemodialysis, which can cause nausea, dizziness, or fainting. Other side effects may include:

  • Chest pain or back pain
  • Headaches
  • Itchy skin
  • Muscle cramps
  • Restless legs syndrome

After peritoneal dialysis
The liquid in your belly can make you feel bloated or full, leading to discomfort, though the treatment itself isn’t painful. Your stomach may also stick out more than usual when filled with fluid.

Outcome

It is possible to live 10 to 20 years on dialysis, with the outlook varying based on age, overall health, the cause of kidney failure, and other factors. A kidney transplant can eliminate the need for dialysis once the new kidney starts functioning. Many individuals on dialysis lead active lives, working, raising families, and traveling. Healthcare providers can arrange dialysis at new locations during travel, and those using self-dialysis can bring portable equipment. While people using peritoneal dialysis may need to limit certain physical activities when their abdomen is filled with dialysis solution, exercise is generally acceptable for dialysis patients. It is important to consult with a healthcare provider about specific activities or sports.

Contact your healthcare provider if you experience:

  • Difficulty urinating
  • Dizziness, fainting, or unusual thirst (dehydration)
  • Nausea and vomiting
  • Signs of infection (fever, oozing, redness at AV fistula or catheter site)
  • Severe abdominal pain
  • Unusual bulge in the abdomen or groin (hernia)