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Saturday, February 7, 2015

What Kind of Dialysis is the "Best"? Which Dialysis Modality should I chose if I have Impending Kidney Failure?

We are years, if not decades away from creating an artificial kidney. Until then, in an ideal world, every patient with advanced stage-5 kidney disease who needs kidney replacement therapy would get a kidney transplant. Unfortunately, kidneys are a scarce and limited resource. The number of people with kidney failure who could use a transplant far outweighs the number of transplants that actually occur every year. As per the latest USRDS Annual Data Report (2013), 17,671 kidney transplants were performed in the United States in 2011 (111 fewer than in 2010). Meanwhile, the waiting list had 90,474 patients in line, as of December 31st of the same year. As you can see, the active waiting list is more than three times larger than the actual supply of donor kidneys. In the light of this stark mismatch, desperate patients have to make a decision about the next best option, dialysis. And the question that any proactive patient will ask, and should ask, is what kind of dialysis is the "best"?

Dialysis is an artificial way of replacing some, but not all, of the kidneys' function. Its role is entirely supportive. It does not cure kidney disease. It just treats its consequences and helps patients stay alive and hopefully, live a better fuller life. 

Median wait time (in years) to get a kidney, by State
Courtesy: www.USRDS.org

I had discussed a while ago about the basics of dialysis. For the sake of clarity, let me reiterate the basics of dialysis below (further information can also be found here: Dialysis 101):


As the name suggests, hemo, or blood dialysis is performed by drawing the patient's blood via a dialysis access (for eg. a shunt in your arm called a fistula, or a catheter inserted in to the patient's veins) and circulating it through a dialysis machine. The machine has an artificial kidney called the dialyzer. As the blood runs through the dialyzer, toxins are filtered and dumped, electrolyte levels are corrected, and clean blood returned to the patient. 

As you might imagine, hemodialysis (HD) would require sticking two needles into the shunt, one to send the blood from the patient to the dialysis machine, and the other needle for returning the blood to the patient. 


Peritoneum is the cavity that surrounds your abdominal organs. Hence, peritoneal dialysis (PD) entails putting a catheter in to the patients belly. The patient hooks the catheter to a source of dialysis fluid (there are no needles or sticking involved). Clean dialysis fluid is instilled into the patients belly via the catheter. Once the fluid is there, your peritoneum's membrane acts like a natural dialyzer and filters toxins from the blood into the dialysis fluid. Later, the fluid is dumped (often automatically by a machine called the "cycler") and clean fluid is re-instilled. This process is repeated multiple times, usually at night while the patient is asleep. 


HD is more often performed in a dialysis unit, typically three times a week for 3-4 hours each. However, it is very much possible to perform HD at home. In this case, patients get to take home a simpler (but as good) dialysis machine and do the treatment themselves. This is called Home HD, and would typically be done more often (5-7 days a week), but for less number of hours (as short as 2 hours per session sometimes). Most patients prefer doing this at night.

PD on the other hand is always a home dialysis modality, done by patients themselves. Again, the typical treatment is done at night since it could be up to 8-10 hours long depending on the number of cycles prescribed by your nephrologist. 

So you can see that both HD and PD can be performed in the comfort and privacy of your home. The term Home Dialysis is used to include these modalities (Home HD, or PD). This is a significant factor that determines which kind of dialysis patients chose. It might also be easier logistically since patients can do it at their own time, and don't have to make frequent trips to the dialysis unit. Another major factor that patients need to consider is their ability to continue to work after starting dialysis. Home dialysis would often give them that flexibility to do their treatments at night and work during daytime. 

Looking at it strictly from a medical standpoint, no dialysis modality has ever been proven to be conclusively better than another. Patients on home dialysis are often reported to do better than others (better electrolytes and blood pressure control, etc), but part of that might be good old selection bias:  the healthier patients tend to chose home dialysis.


It might seem that I am pushing home dialysis here. Well, that is not entirely true, although I must admit that I am a big fan. For the right patient, home dialysis is a great choice. If the patient has the inclination and the means, and is willing to learn, nothing can beat the freedom that comes with home dialysis. You can work, you can travel, and you have more of "a life". But to paraphrase Stan Lee (or Voltaire, depending on whom you talk to!), "with great freedom comes great responsibility". Patients have to be willing to take ownership of their healths. You have to obsessive about cleanliness and best practices, for instance. You disregard standard precautions once, and you could end up with a nasty infection like peritonitis (if you are on PD, that is). 

So if you are facing this quandary today, ask yourself a few basic questions. Are you able and willing to learn how to do home dialysis (whether Home HD or PD, the training can run into a few weeks)? Do you have a reasonably clean living space? Are you too frail to do it? Do you have a lot of pets who might be around during treatments? Do you have someone to help or watch you if you are not sure? Do you want to work or travel?

Quite simply speaking, the decision about which kind of dialysis to chose is more of a social and lifestyle, than a medical choice.

Bradenton, Sarasota, Lakewood Ranch, FL


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