From NDTV, India
Wearable Artificial Kidney May Replace Dialysis, Shows New Clinical Trial
The technology may become an alternative to conventional hemodialysis for people with end-stage kidney disease.
Present-day treatment generally requires three sessions a week on a stationary machine that restricts patients' ability to walk around while it is attached and running.
In contrast, a wearable device would allow patients to be mobile and untethered. It could also provide additional treatment benefits from longer sessions or more frequent days of dialysis.
The clinical trial of a prototype for such a device was performed with seven patients at University of Washington Medical Centre in the US last year. The patients were treated with the device for up to 24 hours.
The US Food and Drug Administration-authorised trial was conducted to determine the safety and efficacy of the device - its ability to take over some functions of failed kidneys.
The researchers also wanted to ask the participants about their impressions of the experimental treatment, and to compare those with standard dialysis treatment.
The device was shown to effectively clear the blood of waste products, like urea, creatinine and phosphorus, while also removing excess water and salt. These are normally filtered out and removed by working kidneys.
The usual diet for patients on standard dialysis is highly limited. In contrast, on the wearable artificial kidney, the patients' blood electrolytes - like sodium and potassium - and their blood fluid volume remained balanced during the test, even without any diet restrictions.
Regulating the volume and composition of body fluids is another job of normal kidneys.
During the trial, the participants tolerated the treatment well and did not have any serious, adverse effects.
The circulatory system, which keeps blood moving throughout the body, stayed stable in all the patients.
However, the trial was stopped after the seventh patient because of technical problems with the device. These included the excessive formation of carbon dioxide gas bubbles in the dialysis solution, and intermittent variations in solution and blood flow.
These technical complications will need to be addressed through device redesign and refinement to enhance safety and reliability prior to any further, long-term studies of the wearable artificial kidney, researchers said.
The findings provide proof of concept that a wearable device along these lines could be developed as a viable, novel dialysis technology, they said.
The patients participating in the study reported greater satisfaction during their treatment with the wearable artificial kidney when compared to their ratings of care during conventional dialysis centre treatment.
The findings were published in the journal JCI Insights.
Living with PKD
From The Wilson Post, Gallatin, Tennessee, by SABRINA GARRETT
Misamore, who grew up in the Pacific Northwest, remembers gathering wild lilies to bring her mother as a girl. "Then as I grew older, I used to watch a show called "Three's Company" and thought how fun it would be to be Janet, one of the characters, because she worked at a flower shop," she recounted.
Misamore carried the dream for years - until 2005. With the support of her husband, Steve, she quit her corporate job and started her own flower shop. Fresh by CarryAnn, now located in Mt. Juliet, was born.
One of the most rewarding aspects of her job as a floral designer is helping brides get ready for their big day.
"After I have met with a bride (and) we gushed over all the details of her imagined wedding day, a few months later I get to hand her the bouquet. It is so personal, and at that moment I think for a bride it all becomes real," she said. "They often get emotional, and I love it."
Regardless of if the creation is for a wedding, charitable event or "just because" - Misamore loves making people smile.
"No one ever sees flowers and frowns. Flowers always bring joy even on a day of loss, they soften the sorrow and fill the sad space," she said.
Misamore herself has had some sad space - being diagnosed with Polycystic Kidney Disease.
"Just saying it out loud was a challenge at one time because I just didn't want anyone to know. It is characterized as a terminal illness because there is no cure," she explained. "PKD causes numerous cysts to grow in the kidneys. These cysts are filled with fluid. If too many cysts grow or if they get too big, the kidneys can become damaged."
About 50 percent of people with PKD have kidney failure by age 60.
In September 2015, Misamore's kidneys had grown so large they had reduced the function to the point that dialysis was needed.
"I made a video (on vimeo.com) asking for a donor," she said. "Vanderbilt received blood kits from people all over the country that wanted to be my donor."
There were more than 50 matches.
"This was overwhelming to me and to Vanderbilt. They had never had such a large response," Misamore said. However, her brother, Kelly Lambson, of Seattle, was her perfect match.
On January 27, 2016, Misamore had both kidneys removed and began dialysis. She had to heal before the transplant could take place.
"With God's grace, on April 12, I had a life-saving, successful kidney transplant. I could not love my brother more and am so grateful to so many people that selflessly offered their kidney, their love to a stranger, the prayers from all over, the support of my church, The Bridge Fellowship, and the amazing abilities and expertise of my Vanderbilt team," she said. "I encourage all women to know - when you feel lost, hurt, devastated, alone, hopeless, overwhelmed or sad - know that miracles happen in each breath, and that even in a dark time God will provide a light."
In her spare time, Misamore enjoys time with her husband of 12 years and their fur-babies, a dog named Toby and a cat named Kathryn.
"I love to go for rides with my husband in 'Ole Red' - his 68 Ford F150. I love baking. I love playing with Toby. I love spending time with my family and I love living."
Misamore admires her mother, Lue Simerly, and her late grandmother, Ann.
"Both of them play a key role in the woman I have become," she said. "In addition, I really am inspired and admire all women. I can look at any woman and find hope. There is a story and an amazing strength in every woman, if you just open your heart and see it."
Dialysis Issues
Medscape spoke with Laura Niklason, MD, who, along with colleagues, recently published a paper[1] in the Lancetreporting results from two clinical trials investigating the application of a new vessel grafting technique.
Medscape: Let's begin by having you explain a bit about the issues facing patients with end-stage renal disease who must undergo dialysis. What are the particular challenges for this group of people?
Dr Niklason: Patients who are on dialysis for kidney failure have a really challenging existence. They have to go to dialysis centers three times a week, for 3-5 hours each session, so that they can have their blood cleansed in the dialysis machine. It's a big burden for them and also very expensive for the healthcare system. It probably costs $80,000-90,000 a year for Medicare to care for each dialysis patient. It's burdensome for the patients, and it's also expensive for the system.
One of the key drivers of patient discomfort and difficulty is failure of what we call "dialysis access." In order to do dialysis, we have to be able to withdraw blood from the patient at a high rate, around 1 L/min, to run it through a dialysis machine and clean the blood. In order to do that, we need a conduit, a connection between the patient's artery and the vein that is sitting underneath the skin. That conduit gets punctured with large-bore needles three times a week in order to draw blood out of a patient, clean it, and then return it to the patient.
One of the things that really contributes to the difficulties of the dialysis patients is when this dialysis conduit fails. When they become clotted, otherwise obstructed, or infected, then this conduit has to be removed, replaced, or intervened upon. And that contributes to morbidity and overall patient misery.
What we're hoping to achieve with this new product, the human acellular vessel, is to hopefully have a graft that will suffer fewer of these complications and/or last longer, so that patients can go substantially longer before they have to get a new conduit placed.
Medscape: Given the difficulties with viable biological alternatives, tell us about how you and your co-investigators settled on culturing acellular vessels.
Dr Niklason: I think, as a comparison to other biological materials, there are two real distinctions of our vessel vs other products or other things that have been tested in man.
Many other biological conduits are derived from animal sources—typically, pig sources or bovine sources, although there are some conduits that are also grown in sheep. For all of those xenogeneic constructs, they all have to undergo crosslinking, often with glutaraldehyde, in order to limit the immunogenicity of the product. When you do that, it becomes very difficult for the patient's own self to repopulate, remodel, and maintain the graft. In some instances, those grafts undergo dilatation and basically flow mechanical failure because the host can't repopulate the tissues. [Read more]
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