Nocturnal Hemodialysis

There was a time in the 1970s when hemodialysis treatment took 8 to 12 hours, three times per week. As technology advanced, dialyzers (the artificial kidney that filters the blood) became able to handle more dialysate (dialysis solution) and higher blood flow rates, so dialysis treatment times were shortened to three to five hours per treatment, three times per week. This quicker dialysis treatment provided patients with more time for their lives, and made time in dialysis centers for more patients to reap the benefits of dialysis.

As other dialysis centers switched to the shorter treatment schedule, one clinic in Tassin, France remained on the longer dialysis program and noticed advantages for patients who were on extended dialysis times.

While many people on dialysis may not want to spend eight hours of their day, three times a week, at their dialysis center, they may want to consider sleeping at the dialysis center overnight, because of some of the health and lifestyle benefits.

Advantages of longer, slower dialysis

The process of hemodialysis can be tough on the body. When hemodialysis is performed slowly over a longer time period, this makes for a gentler hemodialysis treatment. The blood and dialysate flow rates are slower than daytime dialysis shifts because the patient dialyzes for about twice the time during nocturnal dialysis. (Instead of dialyzing three to five hours, nocturnal patients dialyze approximately eight hours per session.) There is a better chance the patient will not be under-dialyzed; therefore, more toxins and fluids may be removed. Because this process occurs more slowly, there is less of a chance of cramping and blood pressure drops during dialysis. Usually, patients do not report the “washed out” feeling after longer dialysis and say they do not need to take a nap after treatment like they would after shorter hemodialysis treatments.

The most notable advantage of the longer dialysis process has been the higher survival rates of the patients in Tassin, France compared to patients who do short, in-center hemodialysis in the United States, Japan and other countries in Europe. According to an article from the Journal of Nephrology (2003; Vol. 16 S.7: S16-S21), “The difference in survival was mainly explained by a lower cardiovascular mortality in the lower pre-dialysis mean arterial pressure subgroup:  12.7 vs. 28.1 cardiovascular deaths per 1,000 patient years.”

Benefits of nocturnal dialysis

Many people who choose nocturnal dialysis report having a better quality of life. Psychologically, nocturnal dialysis patients state that they have more control over their life. There is more time to work, attend school, take care of their children and enjoy social events during the day because they are not spending their daytime hours on dialysis. They feel that the nighttime dialysis schedule makes them feel “more normal” because nonproductive time, where they would be “sleeping anyway”, is now used for treatment. Some feel that they no longer need to tell people they are on dialysis, because the nocturnal dialysis schedule does not interfere with their working or social lives. Staff members working the nocturnal dialysis shift comment their nocturnal patients have a new “zest for life.”

In addition to emotional benefits, there are many physical improvements noticed by patients. Many patients say they feel much better and find they have a much better appetite after beginning nocturnal dialysis. Patients have a higher Kt/V (adequacy of dialysis) indicating their blood is cleaner.

Ironically, nurses reported that while nocturnal dialysis lasts about twice as long as daytime dialysis, nocturnal patients are far less likely to ask to end their dialysis sessions early compared to patients on the daytime shifts. Overall, people who choose nocturnal dialysis report feeling better emotionally and physically.

Disadvantages of nocturnal dialysis

For people who try nocturnal dialysis and then decide it’s not for them, the number one reason is because they cannot sleep at night while on dialysis. During the night the technicians need to check on patients and record blood pressure and other information. The daytime shift checks patients every 30 minutes; however, at night the checks are performed every hour to help patients sleep better. Even with fewer checks patients still report being awakened by the blood pressure cuff inflating.

Even though dialysis is being performed for a longer amount of time, there are still diet restrictions that need to be followed. Because patients feel better and have a better appetite sometimes it is more difficult to control their diet. Weight gain has been noticed among patients who choose nocturnal dialysis. Fluid gain between dialysis sessions can also be a problem because patients believe the longer dialysis will be able to take off all the fluid.

While there were improvements in lab reports of patients doing nocturnal dialysis, the numbers were not as significant as the Tassin, France group or other studies. Perhaps working closely with patients to improve diet and fluid compliance, along with modifying the sodium content of the dialysate, can produce results more on par with the Tassin, France example. (Dialysate is made up of an acidified solution, bicarbonate and purified water. The acidified solution contains electrolytes and minerals, including sodium.)   

Nocturnal dialysis in a dialysis center

For nocturnal dialysis, patients arrive at the dialysis center in the evening and receive approximately eight hours of dialysis treatment during the night. Patients sleep at the clinic three nights a week while they are attached to the dialysis machine. On nights when they dialyze, patients usually get into the center around 7:00 p.m. and are hooked up to the dialysis machine. They are able to bring their dinner, watch television, read a book, listen to music, chat with their health care staff or each other, or any other activity they can do at dialysis.

Patients are asked to bring their pillow, blanket, toothbrush and other items to make them feel “at home.” At about 11:00 p.m. the lights are turned down. At that time people either fall asleep, or quietly continue their activities as not to disturb each other. After lights out the patients normally only have about four to five hours of treatment left. Treatment is usually over before 5:00 a.m. Patients are taken off dialysis and able to go home and start their days, usually before early-morning traffic.

Staff members report that the nocturnal dialysis setting is more peaceful and relaxed than the daytime. The health care staff and patients are able to spend more time talking to each other and find there is more closeness between the patients and the health care team.


While a majority of the people using nocturnal dialysis as their dialysis treatment choice report feeling better and enjoying a better quality of life, this dialysis schedule isn’t for everyone. People going to the center for nocturnal hemodialysis will need dependable transportation and be able to sleep at the center three nights per week. For some, nocturnal hemodialysis is a treatment with many benefits.