Cost-effective dialysis for the developing world.

INTRODUCTION Dialysis is an effective treatment for end-stage renal disease, but it is available to only approximately half of those who need it in the world. METHODS Two prototype passive-flow dialysate delivery systems were constructed. 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. CONCLUSION In principle, costs of providing hemodialysis could be reduced and equipment created to function without electricity by exploiting passive-flow techniques.