Dialysis: Purpose, Types, Risks, Alternative Treatment, Preparation and Outlook


Dialysis is a treatment that filters and purifies the blood using a machine.

September 3, 2018

Dialysis is a treatment that filters and purifies the blood using a machine. This helps keep your fluids and electrolytes in balance when the kidneys are unable to perform their job.
The function of kidneys is to filter your blood by removing waste and excess fluid from your body. This waste is sent to the bladder which is eliminated through urine. As the body functions, the cells use energy and the operation of the cells produces waste products that must be removed from the body. When these waste products are not removed properly, they build up in the body. The elevation of waste products can be measured in the blood, which is called azotemia. Due to accumulation of waste product such as urea and other nitrogenous waste compounds, a sick feeling is developed throughout the body called uremia. Dialysis performs the function of the kidneys when they have failed. End stage kidney failure occurs when the kidneys are performing at only 10 to 15 percent of their normal function. Dialysis is a procedure that is a substitute for many of the normal functions of the kidneys. The kidneys are two organs located on either side in the back of the abdominal cavity. Dialysis can allow individuals to live productive and useful lives, even though their kidneys no longer work adequately.

Purpose of Dialysis:

Kidneys prevent extra water, waste, and other impurities from accumulating in your body when they are working properly. They also help control blood pressure and regulate the levels of sodium and potassium. Your kidneys even activate a form of vitamin D that improves the absorption of calcium.
Dialysis can help keep the body running as normally as possible when your kidneys can't perform these functions due to disease or injury. Salts and other waste products will accumulate in the blood, which will poison the body and damage other organs without dialysis.
However, dialysis isn't a cure for kidney disease or other problems affecting the kidneys. It allows people with kidney failure a chance to live productive lives. Dialysis can provide some people an extended life, and in others, it provides additional time to locate an appropriate donor kidney for a kidney transplant.

Types of Dialysis:

There are three different types of dialysis. These include:

Hemodialysis:

Hemodialysis is the most common type of dialysis. In this procedure uses an artificial kidney called as hemodialyzer is used to remove waste and extra fluid from the blood. The blood is removed from the body and filtered through the artificial kidney. The filtered blood is then returned to the body with the help of a dialysis machine.
A surgery will be performed by your doctor to create an entrance point called as vascular access into your blood vessels to get the blood to flow to the artificial kidney. The three types of entrance points are:

  • Arteriovenous (AV) fistula: This type connects an artery and a vein. It is the preferred option.
  • AV graft: This type is a looped tube.
  • Vascular access catheter: This may be inserted into the large vein in your neck.
  • Both the AV fistula and AV graft are designed for long term dialysis treatments. With in two to three months of AV fistulas surgery, the patients are healed and ready to begin hemodialysis. People who receive AV grafts are ready in two to three weeks. Catheters are designed for short term or temporary use.

Hemodialysis treatments usually last three to five hours and are performed three times per week. However, it can also be completed in shorter and more frequent sessions. The length of treatment depends on your body size, the amount of waste in your body, and the current state of your health. It is usually performed at a hospital, doctor's office, or dialysis center. For long term treatment, you can give yourself dialysis treatments at home after an extended period of time.

Peritoneal dialysis:

In this procedure a peritoneal dialysis (PD) catheter will be implanted into your abdomen by surgery. The catheter helps filter your blood through a membrane in your abdomen called peritoneum. A special fluid called dialysate flows into the peritoneum during treatment. The dialysate absorbs waste. Once the dialysate draws waste out of the bloodstream, it is drained from your abdomen. This process takes a few hours and needs to be repeated four to six times per day. The exchange of fluids can be performed while you are sleeping or awake.
The different types of peritoneal dialysis are:
Continuous ambulatory peritoneal dialysis (CAPD): In CAPD, your abdomen is filled and drained multiple times each day. This method doesn't require a machine and must be performed while awake.

  • Continuous cycling peritoneal dialysis (CCPD): CCPD uses a machine to cycle the fluid in and out of your abdomen. It is usually performed at night while you sleep.
  • Intermittent peritoneal dialysis (IPD): This treatment is usually performed in the hospital. But it may be performed at home also. It uses the same machine as CCPD, but the process takes longer.
  • Continuous renal replacement therapy (CRRT): This therapy also known as hemofiltration is used for people with acute kidney failure. It is primarily done in the intensive care unit. In this procedure a machine passes the blood through tubing. A filter then removes waste products and water. The blood is returned to the body, along with replacement fluid. This procedure is performed 12 to 24 hours a day, generally every day.

Both hemodialysis and peritoneal dialysis can be performed at home. Peritoneal dialysis can be performed alone, while hemodialysis requires a partner. A friend or family member can help you in this, or you can opt to hire a dialysis nurse.
You can receive thorough training from a medical professional beforehand in either type of treatment.

Risks associated with Dialysis:

Risk associated with all three forms of dialysis are different. These include:

Risks associated with Hemodialysis:

Hemodialysis risks include:

  • low blood pressure
  • anemia, or not having enough red blood cells
  • itching
  • high blood potassium levels
  • difficulty sleeping
  • muscle cramping
  • pericarditis, an inflammation of the membrane around the heart
  • sepsis
  • bacteremia, or a bloodstream infection
  • irregular heartbeat
  • sudden cardiac death, the leading cause of death in people undergoing dialysis

Risks associated with Peritoneal dialysis

There is an increased risk for infections in or around the catheter site in the abdominal cavity in case of Peritoneal dialysis. A person can experience peritonitis, which is an infection of the membrane lining the abdominal wall after catheter implantation.
Other risks include:

  • fever
  • stomach pain
  • abdominal muscle weakening
  • high blood sugar due to the dextrose in the dialysate
  • weight gain
  • hernia

Risks associated with CRRT

The risks associated with CRRT include:

  • infection
  • bleeding
  • delayed renal recovery
  • hypothermia
  • low blood pressure
  • electrolyte disturbances
  • weakening of bones
  • anaphylaxis

Inform your healthcare provider performing the treatment, if you experience these symptoms while on dialysis. People who undergo long term dialysis treatments are also at risk of developing other medical conditions, such as amyloidosis. This disease can occur when amyloid proteins produced in bone marrow build up in organs such as the kidneys, liver, and heart, causing joint pain, stiffness, and swelling. Some people may also develop depression after receiving a diagnosis of long term kidney failure.

Alternative Treatment to Dialysis:

People experiencing severe, acute kidney failure usually do not choose dialysis. The reason for not choosing it may be because it is time consuming and expensive.
There are other treatment options that may help manage your symptoms if you decide not to choose dialysis as your treatment option.
One of these options is management of anemia. The hormone erythropoietin (EPO) is produced naturally in the body when kidneys work properly. You can get an injection of EPO every week to help with an under functioning kidney. Maintaining good blood pressure can help slow the deterioration of your kidney. To avoid dehydration drink more fluids. However, it is important to talk to your doctor before taking any anti-inflammatory drugs, including ibuprofen and diclofenac. A kidney transplant is another option for some people which is also a long term commitment. However it is not suitable for everyone. Therefore talk to your doctor to check if a transplant is suitable for you.
You might not be a good candidate for a kidney transplant if you:

  • smoke
  • heavily use alcohol
  • are obese
  • have an untreated mental health condition

Preparation for Dialysis:

A surgical implant of a tube or device will be done by your doctor before your first dialysis treatment to gain access to your bloodstream. This is typically a quick operation and you should be able to return home the same day. Wearing comfortable clothing during your dialysis treatments are advisable. Certain instructions such as fasting for a certain amount of time before the treatment should be followed.

Outlook for Dialysis:

Not necessarily all kidney disorders are permanent. In such cases where there is a chance of cure, dialysis can temporarily serve the same function as kidneys until the functions of your own kidneys are back to normal again. However, the kidneys rarely get better in chronic kidney disease. You must go on dialysis permanently or until a kidney transplant becomes an option if you have this condition. Your nephrologist should have a dietician on their team to help guide dietary choices as there is a need of lifestyle changes. Limit your intake of potassium, phosphorus, and sodium while on hemodialysis. This includes sodium from vegetable juice and sports drinks. You will also need to keep a record of how much liquid you consume as having too much fluid in the body can cause problems.
Being consistent with your dialysis will decrease your chances of needing a kidney transplant. Weight and blood pressure are the two measurements that can help determine whether the dialysis is effective and if you can consider stopping it. However, stopping dialysis will eventually lead to death if the condition causing the kidney failure has not been corrected.
You should talk to mental health professional before ending this life-saving treatment. The expected lifespan of a patient receiving dialysis in the United States Renal Data System (USRDS) report was approximately 8 years for dialysis patients 40 to 44 years of age and approximately 4.5 years for those 60 to 64 years of age. This is a highly variable range that is dependent on many factors such as:

  • race
  • age of patient
  • quality of dialysis treatment
  • other medical issues in the patient
  • quality of pre-dialysis treatment
  • control of potassium levels
  • overall compliance of the patient

In case of some patients dialysis can be done till the time to locate an appropriate donor kidney to get a kidney transplant. The survival prognosis increases greatly if a patient is successful in getting a transplant and is able to stop dialysis.