Our kidneys perform an important job every day. They remove waste products and extra fluid from the blood and help maintain the balance of minerals and other substances in the body. When the kidneys become severely damaged and cannot perform enough of this work, doctors may recommend dialysis. Dialysis helps remove waste and extra fluid from the body when the kidneys can no longer do enough on their own. It can also help maintain important chemical balances in the blood.

Hearing the word “dialysis” can feel frightening for patients and their families. Many people have questions about how dialysis works, how long treatment takes, whether it hurts, what happens during a session, and what changes a person needs to make in daily life.

What Are the Main Types of Dialysis?

There are two main types of dialysis:

Type	How It Works	Common Setting
Hemodialysis	Blood passes through a special filter outside the body	Dialysis centre or home
Peritoneal dialysis	The lining of the abdomen helps filter the blood inside the body	Usually at home

Both methods remove waste and extra fluid, but they work in different ways. The suitable option depends on a person’s medical condition, lifestyle, treatment needs, and advice from the healthcare team.

How Does the Hemodialysis Process Work?

Hemodialysis uses a dialysis machine and a filter called a dialyzer. The dialyzer works like an artificial kidney by helping remove waste and extra fluid from the blood. Before regular hemodialysis starts, the medical team needs a way to safely move blood out of the body and return it after filtering. This is called vascular access. A common long-term option is an arteriovenous fistula, which connects an artery and vein. Other forms of access may also be used depending on the person’s situation.

What Happens During a Hemodialysis Session?

A typical treatment follows several steps.

1. The Patient Arrives for Treatment

At a dialysis centre, the healthcare team usually checks important measurements such as blood pressure and weight before treatment. The weight can help the team understand how much extra fluid the person may have gained since the previous treatment. The exact treatment plan depends on the patient’s dialysis prescription.

2. Blood Access Is Connected

For patients with a fistula or graft, needles connect the blood vessels to the dialysis machine. The machine then moves blood through the dialysis circuit. The healthcare team monitors the patient and the machine during treatment.

3. Blood Passes Through the Dialyzer

The machine pumps blood through the dialyzer. Inside the dialyzer, blood passes through very thin fibres. Dialysis solution flows on the other side of these fibres. Waste products and certain extra substances move from the blood into the dialysis solution while the cleaned blood stays in the fibres.

4. Cleaned Blood Returns to the Body

After passing through the filter, the blood returns to the person’s body. The machine also controls the movement of blood and helps remove the amount of fluid prescribed by the healthcare team.

5. Treatment Ends

After the prescribed treatment time, the blood circuit is disconnected according to the centre’s procedure. The healthcare team may again check blood pressure and other measurements before the patient leaves.

How Long Does Hemodialysis Take?

Treatment time varies from person to person. For many people receiving standard in-centre hemodialysis, sessions commonly last around four hours and often take place several times a week. However, the exact schedule depends on the individual’s medical needs and dialysis prescription. People should not compare their dialysis schedule with another patient’s schedule and assume that both need the same treatment.

What Is Peritoneal Dialysis?

Peritoneal dialysis works differently than hemodialysis because it doesn’t filter blood outside the body. Instead, it uses the natural lining of your abdomen—called the peritoneum—as a built-in filter to clean your blood right inside your body.

Here is a simpler way to explain that process:

A doctor places a soft tube into your belly, and a special cleaning liquid flows through it. This liquid absorbs wastes and extra fluid from your blood. Finally, the used liquid is drained out and replaced with fresh liquid.

How Does a Peritoneal Dialysis Exchange Work?

An exchange generally involves three basic stages.

• Filling: Fresh dialysis solution flows into the abdomen through the catheter.
• Dwell: The solution stays inside the abdomen for a prescribed period. During this time, waste and extra fluid move from the blood into the dialysis solution.
• Draining: The used solution drains out through the catheter. Fresh solution can then be added to start another exchange.

The number and timing of exchanges depend on the type of peritoneal dialysis and the patient’s treatment plan.

CAPD and Automated Peritoneal Dialysis

The two most common ways to do peritoneal dialysis are continuous ambulatory and automated peritoneal dialysis.

With CAPD, the patient performs exchanges manually during the day. With automated peritoneal dialysis, a machine called a cycler performs several exchanges, commonly during sleep.

A healthcare team trains patients and caregivers before they perform peritoneal dialysis at home.

What Does Dialysis Remove From the Body?

It mainly helps remove substances that can build up when the kidneys cannot filter the blood properly.

These include:

• Waste products
• Extra fluid
• Extra salt and certain minerals
• Excess potassium in appropriate dialysis treatment

It also helps control fluid and mineral balance. However, it does not perform every function of healthy kidneys. This explains why dialysis treatment often works together with medicines, blood tests, food choices, and fluid management.

What Can a Person Expect After Dialysis?

People can respond differently to dialysis. After treatment, some people feel much better once the waste and extra fluid are gone. However, others might feel tired or deal with issues like muscle cramps or low blood pressure. Fortunately, your dialysis team is always watching closely and can adjust things to help you stay as comfortable as possible.

If a patient develops unusual or severe symptoms, they should contact their healthcare team rather than assuming the symptoms are a normal part of dialysis.

Diet and Fluid Management During Dialysis

It does not mean that every patient must follow exactly the same diet. A person’s food and fluid requirements depend on factors such as kidney function, dialysis type, blood test results, and other health conditions.

Doctors and renal dietitians may advise patients to manage foods containing sodium, potassium, or phosphorus and may recommend an appropriate fluid intake. Peritoneal dialysis can have different dietary and fluid considerations from hemodialysis.

The safest approach is to follow the diet plan provided by the patient’s kidney specialist or renal dietitian instead of following a general diet chart found online.

Is Dialysis Painful?

Dialysis itself does not necessarily cause pain, but some parts of treatment can feel uncomfortable.

For example, people receiving hemodialysis through needles may feel discomfort when the needles enter the access site. Some people may also experience symptoms during treatment, such as low blood pressure or muscle cramps.

Peritoneal dialysis does not require the repeated blood needles used for standard in-centre hemodialysis. However, it requires a catheter in the abdomen and careful handling of the equipment and supplies. If pain or discomfort becomes persistent or severe, the patient should tell the dialysis team.

What Are the Possible Problems With Dialysis?

It is an important treatment, but it can have complications.

• For hemodialysis, possible problems can include changes in blood pressure, muscle cramps, and issues related to vascular access.
• For peritoneal dialysis, infection around the catheter or inside the abdominal cavity can occur. Proper training and hygiene play an important role in reducing infection risk.

Patients should learn which warning signs require urgent medical attention from their own healthcare team.

Dialysis and Daily Life

Starting dialysis can change a person’s daily routine. Treatment appointments, medicines, food choices, fluid management and medical tests can become part of everyday life. However, many people continue to work, spend time with family and maintain normal activities while receiving dialysis.

The right routine depends on the person’s health, dialysis type, and treatment schedule. Patients should discuss work, travel, exercise, and other daily activities with their healthcare team.

Conclusion

Dialysis treatment varies from one person to another. The schedule, diet, fluid intake, medicines, and treatment method should come from the patient’s kidney specialist and healthcare team. For patients and families, understanding the process can make dialysis feel less confusing. If someone has been advised to start dialysis, asking the doctor about the treatment type, expected schedule, access method, diet, possible side effects, and long-term treatment plan can help the family prepare better.