Wearable Artificial Kidney Passes Test
FRIDAY Dec. 14, 2007 -- The first version of an American-designed wearable artificial kidney has delivered promising results in a pilot trial, British physicians report.
Five men and three women newly diagnosed with end-stage kidney failure used the device for between four and eight hours, according to a report in the Dec. 15 issue of the journal The Lancet.
The device resembles a large tool-belt hung with a variety of devices needed for the dialysis process. Using miniaturized components, it produced satisfactory, if small, rates of blood flow and clearance of toxins from the body, the report said.
That slow rate actually offers an advantage over standard dialysis, said Dr. Garabed Eknoyan, professor of medicine at Baylor College of Medicine, who wrote an accompanying editorial.
Dialysis now is done in three- or four-hour sessions, three times a week, Eknoyan said. "There are two major problems," he said. "The changes occur fast, and removal occurs very fast, before the body gets a chance to accommodate, so there is discomfort with the process. If you dialyse at a lower rate for a longer period, the patient does better."
But dialyzing at a slower rate using a standard artificial kidney has major disadvantages, Eknoyan said. "The patient is tied down to the machine," he said. "Not every patient is willing to cope with that."
The new device was designed by Dr. Victor Gura, a nephrologist at the University of California, Los Angeles. He is chief medical officer of Xcorporeal Inc., the company that made the device.
The discomfort and inefficiency of current dialysis treatment is becoming a bigger issue every years, said Dr. William Henry Fissell, director of the Cleveland Clinic Center for Extracorporeal Therapy.
"The population of patients requiring dialysis has been growing by 8 percent a year for a quarter-century," Fissell said. "The United States now has 400,000 patients on maintenance dialysis."
That increase is due to the growing ability of physicians to prolong the lives of people with the various aliments associated with cardiovascular risk factors such as diabetes and obesity, he said. Kept alive, many of those people will eventually develop kidney failure, Fissell said, and they often find current dialysis therapy unsatisfactory.
An informal network of kidney experts is working to develop better dialysis technology, and the new device is one example of the effort, Fissell said.
Major tests lie ahead, Eknoyan said. "Now that it has passed this stage of trial, we must go to the stage where people use it several times a day," he said. "It remains to be seen how it is going to work. But the evidence is there, and the need is there that people need to dialyze more frequently."
There's more on kidney failure and dialysis at the U.S. National Library of Medicine.
Posted: December 2007