|Wearable artificial kidney--Courtesy of the University of Washington|
While hemodialysis has improved since its introduction in the 1960s, there are still some drawbacks, most notably being tethered to a machine for several hours, multiple times a week. The University of Washington Medical Center in Seattle has tested a wearable artificial kidney (WAK) that could give patients more freedom while dialyzing.
The WAK comprises miniaturized dialyzer components worn around the waist like a tool belt. It is connected to patients by a catheter, according to a University of Washington article. The data from the 7-patient safety and efficacy trial were published last week in JCI Insight.
No serious adverse events were recorded and the device effectively cleared the patients' blood of waste, such as urea, creatinine and phosphorus, as well as excess water and salt. It also regulated body fluid volume and composition the way a real kidney would.
Chuck Lee was the first patient to test the device and preferred it to a traditional dialyzer. Because dialysis is given three times a week, patients must control the amount of liquid they drink and restrict their diets. Conversely, the WAK cleans the blood continuously, so there was no need for patients to watch their diets for the time they were testing the WAK, which was up to 24 hours.
|Chuck Lee wearing the WAK beside a traditional dialyzer--Courtesy of the University of Washington|
Ten patients consented to participate in the trial, but the investigators ended it after the seventh patient due to some "technical problems." These included excessive formation of carbon dioxide bubbles in the dialysis solution and "intermittent variations" in the solution and blood flow. The team, which includes the device's inventor, Dr. Victor Gura of Cedars-Sinai Medical Center, plans to address these issues in a device redesign before kicking off further studies.
More than 600,000 Americans have end-stage kidney disease and must undergo regular dialysis for the rest of their lives. Travel is tricky, Lee said in a University of Washington video, mentioning the need to arrange dialysis appointments at the destination well in advance. The researchers aim to get the device cleared for home use to be administered by the patient or by a caregiver, thus giving dialysis patients more independence to travel.
Meanwhile, UC San Francisco scientists are working on an even smaller, implantable artificial kidney. It is made of a silicon nanofilter that removes waste from the blood and a "bioreactor" containing human kidney tubule cells that perform metabolic functions and control blood volume. They hope it will be a viable alternative for kidney transplants or dialysis for kidney disease patients.