Overview
Individuals with damaged or failed kidneys face difficulty in eliminating unwanted and waste substances from the blood. Dialysis is an alternate, artificial method of carrying out this process. It is the only treatment that does not involve transplantation, and yet allows a patient with end-stage organ failure to live a long, healthy and productive life. Dialysis substitutes the kidneys’ natural functions. Therefore, it is also called Renal Replacement Therapy (RRT).
Healthy kidneys remove waste and regulate the levels of water and minerals in the body. They also secrete certain products that are vital in metabolism. Dialysis, however, cannot do this.
What are Kidneys?
The kidneys are organs that are:
- Shaped like a kidney bean
- Slightly larger than your fist
- Located in your mid-back tucked up under your ribs on each side of the spine
- Most people have two kidneys.
What do the Kidneys do?
The kidneys have many important jobs that keep you healthy. Your kidneys are very important to your health. The kidneys have 5 main jobs:
- Make urine
- Filter blood to take out the wastes
- Balance chemicals such as sodium and potassium (electrolytes) in your blood
- Help control blood pressure
- Help to make red blood cells
What causes kidney disease?
There are several factors that can lead to kidney disease.
- Most kidney disease is from damage to the tiny blood vessels in the kidney.
When this happens:
– The kidney does not get enough blood flow
– The blood is not cleaned
– Fluids and wastes can build up in the body
- Sometimes controlling the underlying health problem can slow progression from kidney disease to kidney failure.
- Some patients have more than one health problem that leads to kidney disease.
- When the kidneys stop working, it is called kidney failure.
What is dialysis?
Healthy kidneys filter about 120 – 150 quarts of blood every day. If the kidneys are not functioning properly, waste builds up in the blood. This can, eventually, lead to coma and death. The causes for disruptions in kidney functions may be due to a long-term or chronic condition, or an acute problem like a disease (short-term) or an injury that affects the kidneys.
Dialysis helps in preventing the waste products in the blood from reaching hazardous levels. Dialysis can also remove drugs or toxins from the blood in an emergency setting. Regular dialysis is recommended to individuals who have lost 85 – 90 percent of their kidney function.
What are the types of Dialysis available?
There are different types of dialysis:
- Hemodialysis
- Peritoneal Dialysis (PD)
- Continuous renal replacement therapies (CRRT)
Hemodialysis
While the word ‘hemo’ means blood, the word ‘dialysis’ means to filter.
- Hemodialysis cleans your blood through a filter.
- Blood flows from your body to the dialysis machine through a special filter.
- The special filter is called a dialyzer.
- The dialyzer is sometimes called an artificial kidney.
- As blood goes through the dialyzer, fluid and wastes are removed.
- The blood goes back to your body after going through the dialyzer. Hemodialysis needs a way to remove blood from the body and return it. This is called access.
Hemodialysis treatments are most often done in an out-patient department 3 times a week. Each session is 3 to 5 hours long. The length of time depends on the person’s condition.
- A doctor places the access in a blood vessel in the patient’s chest or arm.
- Access allows blood to flow to the machine where the wastes are removed.
- Blood is returned to the patient through access.
- Some patients can do hemodialysis treatments at home.
- Home treatments are most often done 5 to 6 times a week.
- The patient needs someone to help them.
- The patient must meet strict aseptic and other requirements.
- Talk to your nephrologist or dialysis nurse if you want to know more about hemodialysis.
Peritoneal Dialysis (PD)
- This is a treatment for kidney failure that uses the body’s own peritoneal membrane.
- Peritoneal dialysis uses the lining of the abdominal cavity to filter your blood. The membrane acts as a filter to remove the fluids and wastes from your body.
- This lining is called the peritoneal membrane. It holds organs like your intestines, liver and stomach in place. One advantage of peritoneal dialysis is that you can do it at home. It allows your schedule to be more flexible.
- A special tube, called a peritoneal catheter, is placed into the abdomen near the belly button.
- A special cleaning fluid, called dialysate, goes into the abdomen through the catheter.
- The fluid stays in the abdomen for a few hours.
- Then it is drained out of the abdomen.
- New fluid is put in.
- This is done 4 times a day.
- In some cases, peritoneal dialysis may be done at night with a machine.
Continuous renal replacement therapy (CRRT)
Dialysis can be either intermittent or continuous. An intermittent dialysis session lasts up to 6 hours. However, Continuous Renal Replacement Therapies (CRRT) are designed to last up to 24-hours in an ICU (Intensive Care Unit).
CRRT are of different types. It can either involve diffusion or filtration. As the fluid (solute) removal is slower, CRRT is tolerated better compared to intermittent dialysis. This may lead to fewer complications, such as a lower chance of hypotension.
