Replacing conventional dialysis with portable or implantable artificial kidneys

Dialysis hasn’t fundamentally changed since the early 1960s. Portable or, ultimately, implantable devices could improve survival rates and quality of life.

Researchers at the University of Washington are focused on portable external dialysis, which might be a nearer-term solution.

Dr. Jonathan Himmelfarb, professor (Nephrology) and Dr. Buddy Ratner, a chemical engineer and bioengineer at the Center for Dialysis Innovation, are developing an artificial kidney that recycles dialysate — the liquid that removes urea and adds back electrolytes — instead of using litres of water to flush it away.

The device is outfitted with a regeneration module, through which dialysate flows after picking up urea from the blood. Inside, ultraviolet light breaks down the absorbed urea into nitrogen and carbon dioxide, which then vent into the air before the dialysate is returned for reuse.

The device could weigh about 14 kilograms, Himmelfarb says — light enough that people could take it with them to the office or on a trip.

“We’re envisioning longer, slower dialysis treatments, perhaps even continuous, like the kidneys work,” he says. That could place less strain on the body. “If we or others can really, truly make mobile forms of dialysis that don’t need connection to an external water system, it’s going to free patients up,” he says.