Portable dialysis system and pump therefor

A lightweight and portable system for dialysing blood wherein blood passes through an exchange station with the blood contacting one side of a semipermeable membrane and dialysate contacting the other side of the semipermeable membrane, said system comprising elastic tube means adapted to be connected to a blood source and to return blood thereto for conducting blood past a plurality of stations, a blood clot detector and an air bubble detector in communication with said blood tube means, elastic tube means adapted to be connected to a source of dialysate for conducting dialysate past a plurality of stations, means for measuring and regulating dialysate flow, pressure, temperature and conductivity, means for maintaining the dialysate at a lower pressure than the blood during passage through the exchange station, a single motor means having the output shaft thereof connected to at least two peristaltic pumps one for transporting blood in said elastic blood tube means and the other for transporting dialysate in said elastic dialysate tube means, mechanism associated with said motor means and said peristaltic pumps for maintaining the dialysate flow at about three times the blood flow, each of said peristaltic pumps having an inner arcuate bearing surface, said blood pump having at least two rollers associated with said inner arcuate bearing surface to trap said blood tube means therebetween, said dialysate pump having a single roller associated with said inner arcuate bearing surface to trap said dialysate tube means therebetween, actuation of said peristaltic blood pump causing smooth laminar flow of blood in said blood tube means due to said rollers, actuation of said peristaltic dialysate pump causing dialysate flow due to a vacuum generated by said single roller resulting in the deformation and return of said elastic dialysate tube means, and control mechanism operatively connected to the blood clot detector and the air bubble detector and to said motor means and to the dialysate flow, pressure, temperature and conductivity measuring means for selectively stopping the dialysate roller thereby halting movement of dialysate through the dialysate tube means and through the exchange station in response to pressure or temperature or conductivity measurements outside of a preselected range while maintaining blood flow and for simultaneously stopping all the rollers in response to a signal from either the blood leak detector or the air bubble detector to shut down the entire system and halt pumping.