Cost-effective dialysis for the developing world.

Results: Each dialysate delivery system provided a flow of dialysate in the range of 200– 300 mL/minute. In one example, flow regulation was good, but ultrafiltration could not be monitored. The second prototype could monitor and regulate ultrafiltration but required repeated manual adjustment to maintain nearly constant dialysate flow. Approaches to the remaining obstacles to a fully passive dialysis system are outlined, but these will require further work to prove feasibility.