In the UK, there are two primary types of dialysis: haemodialysis and peritoneal dialysis. Both methods are designed to filter the blood and remove excess fluid when the kidneys are no longer able to function effectively. While both treatments are equally effective at cleaning the blood, they differ significantly in how they are performed, where they take place, and how they impact a person’s daily routine. Under current NICE guidance, patients should be offered a choice of dialysis modality and setting, provided it is clinically safe for them.
What We’ll Discuss in This Article
- The mechanical process of haemodialysis (HD)
- The biological process of peritoneal dialysis (PD)
- Differences between hospital-based and home-based treatment
- Sub-types of peritoneal dialysis: CAPD and APD
- How haemodiafiltration (HDF) differs from standard dialysis
- Lifestyle and dietary considerations for each modality
Haemodialysis (HD)
Haemodialysis is the most common form of dialysis in the UK. It involves diverting blood into an external machine called a dialyser, which acts as an artificial kidney. Inside the dialyser, blood flows on one side of a semi-permeable membrane while a special cleaning fluid (dialysate) flows on the other. This allows waste products and extra water to pass out of the blood and into the fluid.
Key aspects of haemodialysis include:
- Access: Requires a surgical procedure to create an arteriovenous (AV) fistula, or the insertion of a central venous catheter (line).
- Schedule: Standard hospital-based treatment typically occurs three times a week for approximately four hours per session.
- Location: Can be performed in a hospital renal unit, a satellite dialysis centre, or at home.
- Physical Impact: Some patients experience fatigue (often called ‘wash-out’), muscle cramps, or low blood pressure during or after sessions.
Peritoneal Dialysis (PD)
Peritoneal dialysis uses the lining of the individual’s own abdomen, known as the peritoneum, as the filter. A soft, flexible tube (catheter) is permanently inserted into the abdomen. Dialysis fluid is pumped through this catheter into the abdominal cavity, where it ‘dwells’ for several hours. During this time, waste products from the tiny blood vessels in the peritoneum move into the fluid, which is then drained away and replaced.
There are two main ways this is performed:
- Continuous Ambulatory Peritoneal Dialysis (CAPD): A manual process where the patient performs four to five fluid exchanges throughout the day. No machine is required, allowing for mobility.
- Automated Peritoneal Dialysis (APD): A machine called a ‘cycler’ performs the exchanges automatically while the patient sleeps at night.
Causes and Need for Different Modalities
The decision of which dialysis type to use is often driven by the underlying cause of kidney failure and the patient’s general health status.
- Vascular Health: If a patient has poor blood vessels that cannot support a fistula, peritoneal dialysis may be the only viable option.
- Abdominal Integrity: Patients who have had extensive abdominal surgery or have certain types of hernias may not be suitable for peritoneal dialysis.
- Heart Stability: Haemodialysis can put strain on the heart due to rapid fluid shifts; therefore, those with heart failure might be better suited to the slower, daily process of peritoneal dialysis.
- Residual Kidney Function: Peritoneal dialysis is often recommended for those who still produce some urine, as it may help preserve that remaining function for longer.
Triggers for Choosing a Specific Type
While patient choice is a priority, certain clinical ‘triggers’ or lifestyle factors may lead a medical team to recommend one type over another.
- Lifestyle Independence: Patients who wish to continue working full-time or who travel frequently often choose APD or home haemodialysis for greater flexibility.
- Age Factors: Peritoneal dialysis is frequently the first choice for very young children (under age two) as it is gentler on their smaller bodies.
- Social Support: Home-based treatments require the patient (or a carer) to be comfortable managing the equipment and maintaining a sterile environment.
- Clinical Urgency: If a patient needs to start dialysis urgently without a pre-existing fistula, they may start with haemodialysis via a neckline while a more permanent solution is planned.
Differentiation: Modality Comparisons in the UK
The following table compares the most common delivery methods for dialysis across the UK.
| Feature | Hospital Haemodialysis | Home Haemodialysis | Peritoneal Dialysis (CAPD/APD) |
| Frequency | 3 times per week | 4 to 7 times per week | Daily (Every day) |
| Independence | Low (Staff managed) | High (Self-managed) | High (Self-managed) |
| Dietary Limits | Strict (Fluid/Potassium) | More flexible | Most flexible |
| Travel Impact | Must book sessions away | Portable machines available | Supplies can be shipped |
| Recovery Time | Longer (Several hours) | Shorter (Due to frequency) | Minimal (Continuous process) |
My final conclusion
There are several ways to receive dialysis in the UK, and the best choice depends on a balance of medical suitability and personal lifestyle. Haemodialysis offers treatment-free days but requires a rigid schedule, whereas peritoneal dialysis and home haemodialysis offer more freedom but require daily commitment. Understanding these options early allows for better preparation, such as the timely creation of a fistula or catheter site.
If you experience severe, sudden, or worsening symptoms such as extreme shortness of breath, chest pain, or a complete stop in urine production, call 999 immediately.
Can I switch between types of dialysis?
Yes, many patients move from peritoneal dialysis to haemodialysis if their abdominal lining becomes less effective over time or if they prefer a change.
Which type of dialysis is the ‘best’?
Clinically, both are equally effective at cleaning the blood; the ‘best’ type is the one that fits most safely and comfortably into your specific life.
Does the NHS pay for home dialysis equipment?
Yes, the NHS covers the cost of the machine, all supplies, and any necessary home plumbing or electrical modifications.
Is there a difference in life expectancy between the types?
Studies generally show similar survival rates for both types, though home-based treatments are often associated with better quality of life.
What is haemodiafiltration (HDF)?
HDF is a version of haemodialysis that uses a different pressure gradient to remove larger waste molecules more effectively; it is increasingly offered in UK units.
Can I go on holiday while on dialysis?
Yes, the UK has a ‘Dialysis Away From Home’ programme, and peritoneal dialysis supplies can often be delivered to your holiday destination.
Authority Snapshot
This article has been reviewed by Dr. Rebecca Fernandez to ensure clinical accuracy and adherence to UK medical standards. Dr. Fernandez is a UK-trained physician with extensive experience across internal medicine and emergency care. The information provided is based on current NHS and NICE guidelines to help patients understand the different renal replacement therapies available in the UK.
