Dynamic weight balancing of flow in kidney failure treatment systems

Abstract

A kidney failure treatment system includes: (i) a dialysate supply; (ii) a weighing device; a control container coupled operably to the weighing device; (iii) a diffusion membrane; (iv) a drain; first and second pumps; (v) a first fluid conduit coupled fluidly to the dialysate supply and the diffusion membrane, the first fluid conduit coupled operably to the first pump; (vi) a second fluid conduit coupled fluidly to the control container and the drain, the second fluid conduit coupled operably to the first pump; and (vii) a third fluid conduit coupled fluidly to the diffusion membrane and the control conduit, the third fluid conduit coupled operably to the second pump.

The invention is claimed as follows: 
     
         1 . A kidney failure treatment system comprising:
 a dialysate supply;   a diffusion membrane;   a drain;   a pump;   a first fluid conduit coupled fluidly to the dialysate supply and the diffusion membrane, the first fluid conduit coupled operably to the pump;   a second fluid conduit coupled fluidly to the drain, the second fluid conduit coupled operably to the pump;   a first loop closing conduit in fluid communication with the first fluid conduit, forming a first closed loop around the pump;   a second loop closing conduit in fluid communication with the second fluid conduit, forming a second closed loop around the pump; and   first and second valves coupled operably with the first and second closed loops, respectively, enabling dialysate to flow selectively through the first and second closed loops.   
     
     
         2 . The kidney failure treatment system of  claim 1 , which is configured such that fresh dialysate flows through the first closed loop and spent dialysate flows through the second closed loop. 
     
     
         3 . The kidney failure treatment system of  claim 1 , which includes a third valve coupled operably with the first closed loop and a fourth valve coupled operably with the second closed loop. 
     
     
         4 . The kidney failure treatment system of  claim 1 , which includes at least one of: (i) a first pressure relief valve coupled operably with the first closed loop, the first pressure relief valve enabling flow of dialysate through the first closed loop to occur when dialysate upstream of the first pressure relief valve reaches a certain pressure and (ii) a second pressure relief valve coupled operably with the second closed loop, the second pressure relief valve enabling flow of dialysate through the second closed loop to occur when dialysate upstream of the second pressure relief valve reaches a certain pressure. 
     
     
         5 . The kidney failure treatment system of  claim 1 , wherein the diffusion membrane is selected form the group consisting of: a dialyzer, a hemofilter and a patient's peritoneum. 
     
     
         6 . A kidney failure treatment system comprising:
 a dialysate supply;   a weighing device;   a control container coupled operably to the weighing device;   a diffusion membrane;   a drain;   a pump;   a first fluid conduit coupled fluidly to the dialysate supply and the diffusion membrane, the first conduit coupled operably to the pump;   a second fluid conduit coupled fluidly to the control container and the drain, the second conduit coupled operably to the pump;   a first loop closing conduit in fluid communication with the first fluid conduit, forming a first closed loop around the pump;   a second loop closing conduit in fluid communication with the second fluid conduit, forming a second closed loop around the pump; and   first and second valves coupled operably with the first and second closed loops, respectively, enabling dialysate to flow selectively through the first and second closed loops.   
     
     
         7 . The kidney failure treatment system of  claim 6 , which includes a third fluid conduit coupled fluidly to the diffusion membrane and the control container, the pump being a first pump, the third fluid conduit coupled operably to a second pump. 
     
     
         8 . The kidney failure treatment system of  claim 7 , wherein at least one of the first pump and the second pump is of a type selected from the group consisting of: a peristaltic pump and a membrane pump. 
     
     
         9 . The kidney failure treatment system of  claim 6 , which includes a logic implementer coupled operably to the weighing device, the logic implementer configured to at least substantially match flow through the first fluid conduit and the second fluid conduit. 
     
     
         10 . The kidney failure treatment system of  claim 6  which includes (i) a third fluid conduit coupled fluidly to the diffusion membrane and the control container, and (ii) a logic implementer operably coupled to the weighing device, the logic implementer configured to set flow through the third fluid conduit so as to remove a desired amount of fluid from a patient. 
     
     
         11 . A kidney failure treatment system comprising:
 a dialysate supply;   a diffusion membrane;   a drain;   a pump;   a first fluid conduit coupled fluidly to the dialysate supply and the diffusion membrane, the first fluid conduit coupled operably to the pump;   a second fluid conduit coupled fluidly to the drain, the second fluid conduit coupled operably to the pump; and   (i) first and second fluid pathways each connected fluidly to the first and second fluid conduits upstream of the pump, (ii) third and fourth fluid pathways each connected fluidly to the first and second fluid conduits downstream of the pump, and (iii) wherein the first, second, third and fourth fluid pathways are configured to enable dialysate from the dialysate supply to be pumped alternatively by the pump through the first fluid conduit to the diffusion membrane or through the second fluid conduit to the first fluid conduit to the diffusion membrane.   
     
     
         12 . The kidney failure treatment system of  claim 11 , which includes first, second, third and fourth valves coupled operably with the first, second, third and fourth fluid pathways, respectively. 
     
     
         13 . The kidney failure treatment system of  claim 12 , which includes fifth and sixth valves coupled operably with the first and second fluid conduits upstream of the pump and seventh and eighth valves coupled operably with the first and second fluid conduits downstream of the pump. 
     
     
         14 . The kidney failure treatment system of  claim 13 , wherein the first, second, third and fourth valves are opened for flowing dialysate from the supply through the first fluid conduit to the diffusion membrane and the fifth, sixth, seventh and eighth valves are opened for flowing dialysate from the supply through the second fluid conduit to the first fluid conduit to the diffusion membrane. 
     
     
         15 . The kidney failure treatment system of  claim 11 , which includes first and second valves coupled operably to the first and second fluid conduits upstream of the pump and third and fourth valves coupled operably to the first and second fluid conduits downstream of the pump. 
     
     
         16 . The kidney failure treatment system of  claim 11 , where the first, second, third and fourth fluid pathways are configured to enable used dialysate to be pumped alternatively by the pump through the second fluid conduit to the drain, or through the first fluid conduit to the diffusion membrane. 
     
     
         17 . The kidney failure treatment system of  claim 11 , where at least one of (i) the first and second fluid pathways are connected fluidly in parallel, or (ii) the third and fourth fluid pathways are connected fluidly in parallel. 
     
     
         18 . A kidney failure treatment system comprising:
 a dialysate supply;   a diffusion membrane;   a weighing device;   a control container coupled operably to the weighing device;   a drain;   a pump;   a first fluid conduit coupled fluidly to the dialysate supply and the diffusion membrane, the first fluid conduit coupled operably to the pump;   a second fluid conduit coupled fluidly to the drain and, the second fluid conduit coupled operably to the pump; and   (i) first and second fluid pathways each connected fluidly to the first and second fluid conduits upstream of the pump, (ii) third and fourth fluid pathways each connected fluidly to the first and second fluid conduits downstream of the pump, and (iii) wherein the first, second, third and fourth fluid pathways are configured to enable dialysate from the dialysate supply and the control container to flow alternatively through the first fluid conduit and the second fluid conduit.   
     
     
         19 . The kidney failure treatment system of  claim 18 , which includes (i) a third fluid conduit coupled fluidly to the diffusion membrane and the control container, and (ii) a logic implementer operably coupled to the weighing device, the logic implementer configured to set a flow rate through the third fluid conduit so as to remove a desired amount of fluid from a patient. 
     
     
         20 . The kidney failure treatment system of  claim 18 , which includes a third fluid conduit coupled fluidly to the diffusion membrane and to the control conduit, the pump a first pump, and the third fluid conduit coupled operably to a second pump. 
     
     
         21 . The kidney failure treatment system of  claim 20 , which includes a logic implementer coupled operably to the weighing device, the logic implementer configured to control the speed of the second pump relative to the speed of the first pump so as to remove a desired amount of fluid from a patient. 
     
     
         22 . The kidney failure treatment system of  claim 18 , which is valved so that at least one of (i) dialysate from the supply can be pumped straight through the first fluid conduit to the diffusion membrane or be bypassed from the first fluid conduit to the second fluid conduit back to the first fluid conduit to the diffusion membrane or (ii) used dialysate from the control container can be pumped straight through the second fluid conduit to the drain or be bypassed from the second fluid conduit to the first fluid conduit back to the second fluid conduit to the drain. 
     
     
         23 . The kidney failure treatment system of  claim 18 , which includes a logic implementer coupled operably to the weighing device, the logic implementer configured to calculate a total volume of fluid removed from a patient.