End Stage Kidney Disease
A common conversation I have with many of my patients with advanced chronic kidney disease is what we should do if they reach end stage kidney disease. I generally begin talking about this when their kidney function drops below 20% (20 mL/min/1.73m2 ). This gives my patients time to think about what is important in their life, and what they would and would not accept. Understandably, some patients take some time to come around to the idea that their kidneys will not last forever.
The choices for end stage kidney disease are:
1. Renal supportive care
2. Transplantation
3. Dialysis
Renal supportive care is a conservative approach which prioritises a person’s quality of life over quantity of life. There is a team of healthcare professionals who can support a person’s physical, mental and spiritual needs as nature takes its course. Renal supportive care is most suitable for those with multiple medical illnesses on top of their kidney disease causing frailty. A recent patient of mine has been struggling at home for the past 2 years, resulting in falls, loss of weight and multiple admissions to hospital. Dialysis and transplant would result in an unacceptable toll on this person’s body. Therefore renal supportive care was chosen.
Transplantation is the most aggressive form of therapy. In the right patient, it offers the best chance of long term survival, with the best quality of life. While there is no strict age cutoff, most of the patients who are transplanted are less than 70 years old. This is because the body has to cope with the rigours of the operation, and potential complications that may follow. This includes infection, transplant rejection, osteoporosis, diabetes, cardiovascular disease, cancer, side effects from anti-rejection medication.
The most common dilemma my patients face is choosing between haemodialysis and peritoneal dialysis. Haemodialysis is where patients are hooked up to a machine three times a week (4-5 hours each session) which directly filters their blood. Peritoneal dialysis is where patients instil dialysis fluid into their abdomen through a catheter (as thick as a drinking straw), which is then drained every few hours. This can be done overnight automatically through a machine. However some patients need to manually perform the dialysis themselves 4 times throughout the day. If we were therefore to think about advantages of each:
Peritoneal dialysis
· Increased freedom – Dialysis may be able to be finished completely and automatically overnight. Even if the patient needs to perform dialysis during the day, this leaves hours in between where they are free to go about their activities during the day. This may especially be important for those who work, or live far away from a hospital. Haemodialysis patients by contrast are tethered to the chair while they dialyse. Most haemodialysis is done at the patient’s closest hospital, where they are given a regular roster of Tuesday, Thursday and Saturday; or Monday, Wednesday and Friday. This may limit flexibility in a person’s lifestyle. Some of my patients travel two hours return to get to and from the unit.
· Longer preservation of urination – Maintenance of a degree of urine output is associated with better survival and quality of life. This may be because of better blood pressure control and kidney clearance of waste. Diet is also usually more liberal as peritoneal dialysis is done continuously, rather than once every 2-3 days. Haemodialysis patients tend to lose their residual urine output more quickly than peritoneal dialysis patients.
I would also favour peritoneal dialysis over haemodialysis in those
· With heart problems – Peritoneal dialysis tends to be gentler on the heart than haemodialysis. Peritoneal dialysis usually remove around 1-2L of fluid slowly over the course of 12-24h of dialysis, and dialysis occurs on a daily basis. By contrast haemodialysis can remove up to 3-4L of fluid over 4 hours. This must be done because the next dialysis session may be 2-3 days away. However the heart has to be able to cope with this strain of fluid shifts. If it does not, some patients feel unwell or drop their blood pressure.
· With needle phobia – Once the peritoneal dialysis catheter is placed, patients simply connect this to the bags of dialysis fluid. No needles are involved. In haemodialysis, fistulas are usually created: a vein and artery are knitted together for the purpose of providing a big blood vessel where two dialysis needles are inserted each session. We can decrease the pain by applying local anaesthetic before needling however.
· Who want to travel – The peritoneal dialysis fluid can simply be packed up and taken on the journey. I have a few patients who enjoy caravanning around Australia. They bring their dialysis supply with them. Haemodialysis patients may find travelling trickier as dialysis units around Australia tend to be at near capacity. When I was working on the Gold Coast, patients knew they needed to book their dialysis spot a year in advance because it is a popular holiday destination!
Haemodialysis
· Sustainable – Haemodialysis atients usually use a fistula, which can last years with regular upkeep. By contrast, peritoneal dialysis on average in Australia lasts around 3-4 years as the abdomen’s dialysis membrane (the peritoneum) becomes scarred with repeated use.
· Less patient responsibility – Haemodialysis units are staffed by nurses who perform the dialysis on the patients. This offloads the stress from the patient and their carers. For example I have a patient who is blind, and would therefore struggle to perform peritoneal dialysis.
· Effect – Haemodialysis can remove more fluid. If a patient’s urine output drops off completely there is a risk that they may not be getting adequate fluid and waste removal from peritoneal dialysis
I would also favour haemodialysis over peritoneal dialysis in those with
· Multiple major abdominal surgeries – Peritoneal membrane integrity is vital for this dialysis option to work. Disruption to the peritoneal membrane from surgeries (eg gallbladder removal, bowel cancer removal) lead to scarring of the membrane and likely inadequate dialysis. Haemodialysis uses a fistula and therefore is unaffected by abdominal surgeries.
· Inadequate storage at home – Haemodialysis is mostly done in hospital, where the equipment and dialysate are readily accessible. Peritoneal dialysis requires multiple boxes of equipment and dialysis fluid to be delivered to the patient’s house, which can sometimes be too intrusive.
· An increased abdominal girth – In haemodialysis, the fistula is created on the limbs (usually on a wrist). In contrast, peritoneal dialysis requires a catheter to be inserted into the patient’s abdomen. The additional weight of abdominal tissue can increase pressure inside the abdomen, leading to increased risk of fluid leak, infections, and less effective dialysis. Further, as the dialysate is made of glucose, this can increase weight further.
Levy, Jeremy B., Edwina Anne Brown, Christine M. Daley and Anastasia Lawrence. “Oxford Handbook of Dialysis.” (2001).
ANZDATA - https://www.anzdata.org.au/wp-content/uploads/2019/09/c05_peritoneal_2018_ar_2019_1.1_20200415-1.pdf
