A renal therapy machine includes a blood filter including a plurality of porous fibers; a blood circuit in communication with the blood filter; and a dialysate circuit in communication with the blood filter and operable with at least one pump, wherein the renal therapy machine is configured to perform a priming sequence in which a physiologically compatible solution, other than dialysate, primes the blood circuit and is flowed within the fibers and through pores in the fibers of the blood filter, and the pump of the dialysate circuit vents air from the blood filter into the dialysate circuit.

Dialysis systems comprising actuators that cooperate to perform dialysis functions and sensors that cooperate to monitor dialysis functions are disclosed. According to one aspect, such a hemodialysis system comprises a user interface model layer, a therapy layer, below the user interface model layer, and a machine layer below the therapy layer. The user interface model layer is configured to manage the state of a graphical user interface and receive inputs from a graphical user interface. The therapy layer is configured to run state machines that generate therapy commands based at least in part on the inputs from the graphical user interface. The machine layer is configured to provide commands for the actuators based on the therapy commands.

A method of draining a device for extracorporeal blood treatment, wherein the device comprises a dialyzer which is divided by means of a membrane into a first chamber and a second chamber, an arterial line connected to a blood inlet of the first chamber, a venous line connected to a blood outlet of the first chamber, a dialysis fluid line for fresh dialysis fluid connected to a dialysis fluid inlet of the second chamber and a dialysis fluid line for used dialysis fluid connected to a dialysis fluid outlet of the second chamber, a blood pump disposed in the arterial line, a venous expansion chamber disposed in the venous line and an air detector unit downstream of the venous expansion chamber, and wherein the method comprises the following steps of: connecting a patient-side port of the arterial line to a patient-side port of the venous line; generating a negative pressure in the second chamber; operating the blood pump in a first direction and draining the arterial and venous lines in the first direction via the membrane and the second chamber; and stopping the blood pump and draining the arterial and venous lines in a second direction opposed to the first direction via the membrane and the second chamber.

A filter CF1 for filtering dialysis fluid comprises the following: a housing 52 inside of which a filter material 51 is accommodated and which is vertically long; an introduction port 53 that is disposed in the lower part of the housing and that introduces dialysis fluid from an upstream-side flow path 23a; a filtered fluid lead-out port 54 through which filtered dialysis fluid, which has passed through the filter material, is lead out from the upper part of the housing to a downstream-side flow path 23b; and an unfiltered fluid lead-out port 55 through which unfiltered fluid is lead out from the upper part of the housing to a waste fluid flow path 57. When removing the filter from a dialysis fluid circuit 4, fluid is suctioned from the inside of the housing via the upstream-side flow path by using fluid suction means 64A, and a gas is caused to flow into the housing from at least either one of the waste fluid flow path and the downstream-side flow path by using gas inflow means 65. The fluid may be suctioned from the downstream-side flow path and the gas may be caused to flow in from the upstream-side flow path, or the fluid may be suctioned from the waste fluid flow path and the gas may be caused to flow in from the downstream-side flow path. Residual fluid in the filter can be reduced.

A drain cassette for a dialysis unit has a fluid channel between venous and arterial connection ports, and a valve may controllably open and close fluid communication between a drain outlet port and the venous connection port or the arterial connection port. A blood circuit assembly and drain cassette may be removable from the dialysis unit, e.g., by hand and without the use of tools. A blood circuit assembly may include a single, unitary member that defines portions of a pair of blood pumps, control valves, channels to accurately position flexible tubing for an occluder, an air trap support, and/or other portions of the assembly. A blood circuit assembly engagement device may assist with retaining a blood circuit assembly on the dialysis unit, and/or with removal of the assembly. An actuator may operate a retainer element and an ejector element that interact with the assembly.

A blood circuit and a dialysate circuit bidirectionally circulate a fluid through a blood purification membrane of a blood purifier, and include a first flow route that causes a dialysate to flow from the dialysate circuit into the blood circuit through a connection flow route connecting the dialysate circuit to the blood circuit while bypassing the blood purifier, and a second flow route that causes the dialysate to flow from the dialysate circuit into the blood circuit through the blood purification membrane. The controller performs control such that blood in the blood circuit is returned to the body by feeding the dialysate to one of these flow routes, determine if a flow amount of the dialysate reaches a predetermined flow amount, and control such that the blood in the blood circuit is returned to the body by feeding the dialysate to the other one of these flow routes.

An extracorporeal blood treatment device and a method for automatic priming of an extracorporeal blood treatment device. The device includes an extracorporeal circuit, a dialyser, a dialysis liquid circuit and a control unit. The control unit is designed to control the priming such that a liquid is delivered from the dialysis liquid circuit via a membrane of the dialyser to the extracorporeal circuit, and to actuate valves and/or pumps in the dialysis liquid circuit such that pressure builds up in the dialyser on the dialysis liquid side. The control unit actuates a flow machine in the extracorporeal circuit to perform a push cycle, in which the flow machine pushes air into the extracorporeal circuit, and a pull cycle, in which the flow machine draws air out from the extracorporeal circuit, to assist a transfer of the liquid through the membrane of the dialyser during the priming process.

The present invention generally relates to hemodialysis and similar dialysis systems, including a variety of systems and methods that would make hemodialysis more efficient, easier, and/or more affordable. One aspect of the invention is generally directed to new fluid circuits for fluid flow. In one set of embodiments, a hemodialysis system may include a blood flow path and a dialysate flow path, where the dialysate flow path includes one or more of a balancing circuit, a mixing circuit, and/or a directing circuit. Preparation of dialysate by the preparation circuit, in some instances, may be decoupled from patient dialysis. In some cases, the circuits are defined, at least partially, within one or more cassettes, optionally interconnected with conduits, pumps, or the like. In one embodiment, the fluid circuit and/or the various fluid flow paths may be at least partially isolated, spatially and/or thermally, from electrical components of the hemodialysis system. In some cases, a gas supply may be provided in fluid communication with the dialysate flow path and/or the dialyzer that, when activated, is able to urge dialysate to pass through the dialyzer and urge blood in the blood flow path back to the patient. Such a system may be useful, for example, in certain emergency situations (e.g., a power failure) where it is desirable to return as much blood to the patient as possible. The hemodialysis system may also include, in another aspect of the invention, one or more fluid handling devices, such as pumps, valves, mixers, or the like, which can be actuated using a control fluid, such as air. In some cases, the control fluid may be delivered to the fluid handling devices using an external pump or other device, which may be detachable in certain instances. In one embodiment, one or more of the fluid handling devices may be generally rigid (e.g., having a spheroid shape), optionally with a diaphragm contained within the device, dividing it into first and second compartments.

Dialysis systems comprising actuators that cooperate to perform dialysis functions and sensors that cooperate to monitor dialysis functions are disclosed. According to one aspect, such a hemodialysis system comprises a user interface model layer, a therapy layer, below the user interface model layer, and a machine layer below the therapy layer. The user interface model layer is configured to manage the state of a graphical user interface and receive inputs from a graphical user interface. The therapy layer is configured to run state machines that generate therapy commands based at least in part on the inputs from the graphical user interface. The machine layer is configured to provide commands for the actuators based on the therapy commands.

Simple-to-use systems, methods, and devices for priming replacement blood treatment devices, for swapping the blood treatment devices out, for replacing swapped-out blood treatment devices, and other related operations are described. In embodiments, a blood treatment device can be primed while a therapy is still running. When the replacement blood treatment device is needed, the therapy can be stopped momentarily (less than a minute) for the rapid and safe swap of the blood treatment device. Blood loss can be minimized. The down time from therapy can be minimized.