Hollow fiber dialyzer

This type of artificial kidney is the most common type used. This artificial kidney makes use of countercurrent flow (Fig 2). Countercurrent flow is where the blood is flowing in one direction and the dialysate is flowing in the opposite direction. Countercurrent flow is less efficient, but seems to be more gentle. Because it is more gentle, it is used on pediatric patients and some first time dialysis patients. The hollow-fiber dialyzer comes in many different sizes. It looks like a cylinder filled with thousands of tiny hollow-fibers(Fig 3). Blood flows into one end of the dialyzer and through these thousands of tiny hollow-fibers. Dialysate, at the same time, is pumped into the cylinder and across the tiny hollow-fibers. This method keeps fresh dialysate circulating constantly.