CN104394900A - Pressure-Based Leak Detection in Extracorporeal Blood Processing Devices - Google Patents

Abstract

The extracorporeal blood treatment apparatus described herein includes components configured to detect leakage of fluid from one or more fluid circuits within the extracorporeal blood treatment apparatus, as well as methods for detecting fluid leakage within the extracorporeal blood treatment apparatus. The components for detecting leakage include one or more fluid-filled pressure lines connected to one or more remote pressure ports of one or more pressure sensors and one or more local pressure ports. The fluid in the pressure lines transmits the pressure exerted by any collected fluid on the remote pressure ports to the local pressure ports of the pressure sensors.

Description

Pressure-Based Leak Detection in Extracorporeal Blood Processing Devices

cross reference

This application claims the benefit of US Provisional Application No. 61/747,718, filed December 31, 2012, the disclosure of which is incorporated herein by reference.

technical field

Described herein are extracorporeal blood treatment devices incorporating means for pressure-based leak detection and methods of use thereof.

Background technique

Extracorporeal blood processing involves obtaining blood from a patient, processing the blood outside the patient's body, and returning the processed blood to the patient. Extracorporeal blood treatment is commonly used to extract unwanted substances or molecules from a patient's blood and/or to add beneficial substances or molecules to the blood. Extracorporeal blood treatment is used for patients who cannot effectively remove substances from their blood, for example in the case of patients suffering from temporary or permanent renal failure. For example, these and other patients may undergo extracorporeal blood treatment to add substances to or remove substances from their blood, to maintain acid-base balance or to remove excess body fluids.

Typically, extracorporeal blood treatment is performed by sampling a patient's blood in a continuous flow and by introducing the blood into the blood cavity of a filter defined at least in part by a semipermeable membrane. Depending on the type of treatment, a semipermeable membrane may selectively allow unwanted substances contained in the blood to pass through the membrane from the blood lumen to the auxiliary lumen, and may selectively allow beneficial substances contained in fluid entering the auxiliary lumen. Substances pass through the membrane into the blood entering the blood cavity.

Some extracorporeal blood treatments can be performed with the same machines. In an ultrafiltration (UF) process, unwanted substances are removed from blood in an auxiliary chamber by convection across a membrane.

In a hemofiltration (HF) process, as in UF, blood flows through a lumen at least partially defined by a semipermeable membrane, and either before or after the blood passes through the filter and before it is returned to the patient, the The fluid is introduced into the blood, adding beneficial substances to the blood.

In hemodialysis (HD) treatment, an auxiliary fluid containing beneficial substances is introduced into the auxiliary lumen of the filter. Unwanted substances in the blood pass through the semipermeable membrane by diffusion and penetrate into the auxiliary fluid, and beneficial substances of the auxiliary fluid can pass through the membrane and penetrate into the blood.

In hemodiafiltration (HDF) treatment, as in HD, blood and auxiliary fluid exchange their substances, and further, as in HF, typically by introducing the fluid into the post-treatment to add substances to the blood; unwanted substances are removed from the blood by convection and diffusion.

In those treatments using an auxiliary fluid, the auxiliary fluid passes through the auxiliary lumen of the filter and receives unwanted substances in the blood that pass through the membrane by diffusion and/or convection. The liquid is then drawn from the filter: it is commonly called waste and is sent to a drain, or to a container and then discharged to a drain.

The extracorporeal blood treatment devices used to achieve these treatments generally include many components, such as: pumps, valves, tubes, sensors, etc., which are connected to each other to form multiple fluid circuits. During use of the device, undesired fluid leakage from one or more fluid circuits may occur at one or more junctions between various components, or due to damage or failure of one or more components.

Although the fluid circuits in an extracorporeal blood treatment set are designed to function without leakage under all operating conditions, under certain circumstances one or more of the fluid circuits in an extracorporeal blood treatment set may potentially leak. In addition to causing undesired loss of material, leaks in fluid circuits in extracorporeal blood treatment devices can damage the device and potentially jeopardize patient treatment.

Contents of the invention

The extracorporeal blood treatment devices described herein include components configured to detect fluid leakage from one or more fluid circuits of an extracorporeal blood treatment device, and methods of detecting fluid leakage from an extracorporeal blood treatment device. The means for detecting leaks includes a remote pressure port connected by a fluid-filled pressure line to a local pressure port on the pressure sensor. The fluid in the pressure line transfers the pressure exerted by any collected liquid on the remote pressure port to the local pressure port of the pressure sensor.

In one or more embodiments, isolating the remote pressure port from the pressure sensor by a fluid-filled pressure line allows the pressure sensor to be electrically connected to the control unit without the need for an electrical connection to the remote pressure port extending to where leaked fluid is collected. Instead, the pressure applied on the remote pressure port is transmitted to the local pressure port of the pressure sensor through a fluid-filled pressure line.

In one or more embodiments, the pressure sensor may be located in the housing as the control unit, while the fluid-filled pressure line extends out of the housing to a liquid collector where the remote pressure port is located. A shortened electrical connection between the pressure sensor and the control unit would be advantageous, since a longer electrical connection extending from the remote pressure port to the control unit could potentially cause electrical interference (especially at locations remote from the device where leaked liquid is collected). In the extracorporeal blood treatment device of the housing). For example, leaking liquid may be detected at the base of the device while the housing is located above the base at a distance of eg more than one meter.

In one or more embodiments, the extracorporeal blood treatment apparatus described herein may include a single remote pressure port connected by a single fluid-filled pressure line to the local pressure port of the pressure sensor. In one or more alternative embodiments, the extracorporeal blood treatment apparatus described herein may comprise two or more remote pressure ports connected to two or more local pressure ports of one or more pressure sensors, wherein Each remote pressure port is connected to its respective local pressure port by a dedicated fluid-filled pressure line. In such an embodiment, the remote pressure ports may be arranged to detect a pressure difference between the two remote pressure ports and use this pressure difference as a basis for determining that a leak has occurred within the extracorporeal blood treatment device.

Although described herein in relation to an extracorporeal blood treatment device configured to perform dialysis using a dialysis solution, similar problems may be encountered in any extracorporeal blood treatment device. For purposes discussed herein, the leak detection device may be incorporated into any extracorporeal blood treatment device, for example, using replacement fluid for convective replacement therapy of renal function, plasma for therapeutic plasma exchange (TPE), albumin, or colloids solution, or any other known type of medical fluid used in connection with extracorporeal blood treatment devices.

In one aspect, one or more embodiments of the extracorporeal blood treatment apparatus described herein include: a housing; a fluid circuit on or in the housing, wherein the fluid circuit includes a fluid circuit configured to one or more pumps and tubing to move blood through the fluid circuit for extracorporeal blood treatment; a fluid collector configured to collect fluid leaking from the fluid circuit; wherein the fluid leaking from the fluid circuit liquid reaches the liquid collector by gravity; and a pressure sensor including a local pressure port on or in the housing, a remote pressure port at a selected location in the liquid collector port and a pressure line extending from the remote pressure port to the local pressure port, the liquid collected by the collector accumulates above the selected location, wherein the local pressure port is positioned at the liquid collection port in the liquid collector such that the liquid collected at the selected location in the liquid collector contacts the remote pressure port, and wherein the pressure line is configured to transfer the pressure applied to the remote pressure port via Fluid in the pressure line is delivered to the local pressure port. The device also includes a control unit operatively connected to the pressure sensor, wherein the control unit is configured to: receive a signal from the pressure sensor, wherein the signal is indicative of a pressure sensed by the remote pressure port; and a determination that fluid is leaking from the fluid circuit when the pressure sensed by the remote pressure port reaches or exceeds a selected pressure limit.

In one or more embodiments of the extracorporeal blood treatment apparatus described herein, the pressure line is connected to the remote pressure port by a fluid tight connector.

In one or more embodiments of the extracorporeal blood treatment apparatus described herein, the pressure line is connected to the local pressure port by a fluid tight connector.

In one or more embodiments of the extracorporeal blood treatment device described herein, the fluid in the pressure line consists essentially of one or more gases.

In one or more embodiments of the extracorporeal blood treatment apparatus described herein, the fluid in the pressure line consists essentially of one or more liquids.

In one or more embodiments of the extracorporeal blood treatment apparatus described herein, the pressure sensor comprises: a second remote pressure port configured to measure atmospheric pressure at a second selected location; The remote pressure port extends to a second pressure line of a second local pressure port of the pressure sensor, wherein the second pressure line is configured to pass the pressure applied on the second remote pressure port through the pressure sensor located at the second pressure port. fluid in the line is delivered to a second local pressure port; and wherein the control unit is configured to sense a pressure difference between the remote pressure port and the second remote pressure port when the difference in pressure reaches or exceeds a selected value, a determination is made that liquid leaks from the liquid circuit. In one or more embodiments, a second selected location is positioned at a selected height relative to said second local pressure port, and wherein the remote pressure at said selected location of said liquid collector The port is also located at said selected height relative to the local pressure port to which it is connected. In one or more embodiments, the fluid in the second pressure line consists essentially of one or more gases. In one or more embodiments, the fluid in the second pressure line consists essentially of one or more liquids.

In one or more embodiments of the extracorporeal blood treatment apparatus described herein, the control unit is operatively connected to a pump of the one or more pumps of the fluid circuit, and wherein the control unit is configured To stop the operation of the pump when the control unit determines that the liquid circuit is leaking.

In a second aspect, one or more embodiments of the method of detecting a leak in an extracorporeal blood treatment apparatus as described herein may include pumping a fluid through a fluid circuit located on or in the housing, the The liquid circuit includes one or more pumps and piping configured to perform extracorporeal blood treatment; collecting liquid leaking from the liquid circuit in a liquid collector located below the housing; detecting pressure exerted by collected liquid on a remote pressure port of a pressure sensor, wherein the pressure sensor is located on or in the housing, and wherein the remote pressure port is located in the liquid collector selected location; transmitting the pressure detected at the remote pressure port to the local pressure port using a pressure line extending from the remote pressure port to the local pressure port of the pressure sensor, wherein the pressure a line delivering pressure from the remote pressure port to the local pressure port through fluid located in the pressure line; and when the pressure sensed by the remote pressure port reaches or exceeds a selected pressure limit , a determination is made that liquid leaks from the liquid circuit.

In a second aspect, one or more embodiments of the method of detecting a leak in an extracorporeal blood treatment apparatus as described herein may include pumping a fluid through a fluid circuit located on or in the housing, the The liquid circuit includes one or more pumps and piping configured to perform extracorporeal blood treatment; collecting liquid leaking from the liquid circuit in a liquid collector located below the housing; detecting pressure exerted by collected liquid on a first remote pressure port, wherein the first remote pressure port is located at a first selected location in the liquid collector, and wherein collected liquid in the collector accumulates above the first remote pressure port; using a first pressure line extending from the first remote pressure port to a first local pressure port of a pressure sensor located on or in the housing will be at Pressure sensed on the first remote pressure port is communicated to the first local pressure port, wherein the first pressure line transfers pressure from the first remote pressure port via a transfer the fluid in the first local pressure port; detect the atmospheric pressure acting on the second remote pressure port; use the second local pressure port extending from the second remote pressure port to the pressure transducer A pressure line communicates atmospheric pressure sensed at the second remote pressure port to the second local pressure port, wherein the second pressure line transmits pressure from the second remote pressure port via the transfer of fluid in the second pressure line to the second local pressure port; and when the difference in pressure sensed by the first remote pressure port and the second remote pressure port reaches or exceeds a selected value, a determination is made that liquid leaks from the liquid circuit. In one or more embodiments, the second remote pressure port is positioned at a selected height relative to the second local pressure port, and wherein the first remote pressure port is also positioned relative to the first The selected height of a local pressure port.

In one or more embodiments of the methods described herein, the fluid in the pressure line consists essentially of one or more gases.

In one or more embodiments of the methods described herein, the method further comprises stopping a pump of the one or more pumps in the liquid circuit after determining that liquid has leaked from the liquid circuit.

As used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a" or "the" component may include one or more components and equivalents thereof known to those skilled in the art. In addition, the term "and/or" refers to one or all of the listed elements, or a combination of any two or more of the listed elements.

It should be noted that the term "comprising" and its variants appearing in the specification do not have a restrictive meaning. Also, "a", "an", "the", "at least one" and "one or more" are used interchangeably herein.

The above summary is not intended to describe each embodiment or every implementation of the extracorporeal blood treatment apparatus and methods described herein. Rather, a more complete understanding of the invention will become apparent and appreciated by reference to the following description of the exemplary embodiments and claims based on the accompanying drawings.

Description of drawings

Figure 1 illustrates an exemplary embodiment of an extracorporeal blood treatment device configured to detect leaks using pressure-based leak detection as described herein.

Figure 2 is a schematic illustration of an exemplary embodiment of an extracorporeal blood treatment apparatus including a fluid circuit as described herein.

Figure 3 is a schematic illustration of another exemplary embodiment of an extracorporeal blood treatment apparatus as described herein.

Detailed ways

In the following description of the exemplary embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of example specific embodiments. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.

An exemplary embodiment of an extracorporeal blood treatment device is shown in FIG. 1 . In one or more embodiments, the extracorporeal blood treatment device 1 is a dialysis machine for treating renal insufficiency, which can perform one or more of the following treatments: hemodialysis, simple ultrafiltration, hemofiltration, hemodiafiltration over, therapeutic plasma exchange, etc.

In the embodiment shown in FIG. 1 , the device 1 is particularly suitable for intensive treatment of acute renal failure and comprises a blood treatment device 2 (eg, a dialyzer filter) and is capable of transferring fluid (eg, blood, dialysis solution, etc.) to the fluid distribution circuit 3 of the blood treatment apparatus 2 . In order to keep the drawing simple and clear, only the support for the fluid distribution circuit 3 is shown in FIG. 1 .

The extracorporeal blood treatment device 1 also comprises one or more pumps 4 for circulating fluid within the fluid distribution circuit 3 . Fluid distribution circuit 3 may be configured to move blood to and from a patient, as well as fluid provided by and/or delivered to reservoir 6, which in the illustrated embodiment is The liquid container 6 is suspended from the bottom end 13 of the housing 12 of the extracorporeal blood treatment device 1 . The reservoir 6 is shown in the form of a bag, however any other suitable container for containing fluid inside may be used instead of a bag.

The extracorporeal blood treatment device 1 shown in FIG. 1 also includes a base 14 on which the housing 12 is supported by a column 16 . The base 14 includes a liquid collector 20 disposed below the bottom end 13 of the housing 12 . The collector 20 is shaped to collect liquid leaking from a liquid circuit in or on the housing 12 of the extracorporeal blood treatment device 1 located above the base 14 . The surface of the collector 20 is shaped and or angled to collect liquid in one area of the collector 20 regardless of where the liquid first contacts the collector 20 . In the embodiment shown in FIG. 1 , for example, the collector 20 includes a surface designed to direct the liquid towards a collection area 23 which is lower than the rest of the collector 20 .

Also visible in the embodiment of the extracorporeal blood treatment apparatus 1 shown in FIG. 1 is the remote pressure port 22, which is used in combination with a pressure sensor to detect leakage of the extracorporeal blood treatment apparatus 1 as described herein. . While two remote pressure ports 22 are shown in the embodiment of FIG. 1 , in one or more other embodiments, as will be described herein, for example, as few as one remote pressure port may be used to perform the methods described herein. The leak detection function of the device.

Figure 2 is a schematic diagram of an exemplary embodiment of an extracorporeal blood treatment apparatus including a fluid circuit as described herein. One part of the depicted fluid circuit comprises a blood pump 4a configured to move blood removed from the patient P using the arterial line 7 and convey it to the blood treatment apparatus 2, eg using the blood pump 4a. The fluid circuit shown in FIG. 2 also includes a venous line 8 for returning blood from the filter 2 to the patient P. As shown in FIG. Another part of the liquid circuit shown in FIG. The dialysate is removed from the blood treatment device 2 and transferred to the reservoir 6b.

Also shown in the exemplary embodiment of the extracorporeal blood treatment device 20 is a collector 20 which is sufficiently large and suitably positioned to collect liquid leaking from a liquid circuit in or on the extracorporeal blood treatment device 1 . Preferably, collector 20 includes a sloped or angled surface such that liquid falling into collector 20 is sent to and collected above where remote pressure port 22 is located. The remote pressure port 22 is connected to a local pressure port 26 on a pressure sensor 28 by a pressure line 24 .

Liquid collected in collector 20 exerts pressure on remote pressure port 22 and this pressure is communicated through fluid-filled pressure line 24 to local pressure port 26 on pressure sensor 28 . As discussed herein, the use of fluid-filled pressure line 24 to transmit the pressure applied to remote pressure port 22 by liquid collected in collector 20 to local pressure port 26 on pressure sensor 28 reduces or eliminates The potential for electrical interference would arise from electrical connections extending on the same path as the fluid-filled pressure line 24 .

In one or more embodiments, remote pressure port 22 may include a membrane or other structure to prevent liquid collected in collector 20 from entering remote pressure port 22 in a manner that would allow it to mix or enter fluid-filled pressure line 24 .

In one or more embodiments of the extracorporeal blood treatment apparatus described herein, a fluid-filled pressure line 24 for communicating pressure from a remote pressure port 22 to a local pressure port 26 of a pressure sensor 28 may be provided via a connector 23 Connects to remote pressure port 22 and connects via connector 27 to local pressure port 26 on pressure sensor 28 . Connectors 23 and 27 may be the same or different, and may take various forms, such as a Luer twist lock connection, a bayonet fit, a hose clamp and fitting, or a fluid connection in pressure line 24 to remote pressure port 22 Any other suitable connection that transmits the required pressure between the leaking liquid and between the fluid in the pressure line 24 and the local pressure port 26.

In one or more embodiments of the extracorporeal blood treatment apparatus described herein, the fluid in pressure line 24 may be of a type capable of transmitting the pressure applied at remote pressure port 22 to pressure transducer 28 with acceptable accuracy. Any suitable fluid from local pressure port 26. Some examples of potentially suitable fluids for use in fluid-filled pressure line 24 may include, for example, air, nitrogen, saline, gel, water, and the like. In one or more embodiments, the fluid-filled pressure lines used in the extracorporeal blood treatment devices described herein may only be filled with gas (e.g., the fluid in the pressure line consists essentially of one or more gases, such as air, nitrogen, etc.), or they may be filled with liquids only (eg, the fluid in the pressure line may consist essentially of one or more liquids).

Another component described in connection with the exemplary embodiment of the extracorporeal blood treatment device 1 in FIG. 2 is the control unit 30 . In the described embodiment, both the blood pump 4 a and the dialysis solution pump 4 b are operatively connected to the control unit 30 . Additionally, a pressure sensor 28 connected to the remote pressure port 22 through a fluid-filled pressure line 24 is also operatively connected to the control unit 30 .

The control unit 30 is configured to receive signals from the pressure sensor 28 . The signal from the pressure sensor 28 is indicative of the pressure sensed at the remote pressure port 22 connected to a local pressure port 26 on the pressure sensor 28 by a fluid-filled pressure line 24 . If the signal received by the control unit 30 from the pressure sensor 28 indicates that the pressure sensed at the remote pressure port 22 exceeds a selected limit, it may be determined that liquid is leaking from the liquid circuit in the extracorporeal blood treatment apparatus 1 .

The selected limit may be a function of the amount of liquid in the collector 20 relative to the height of the liquid in the collector 20 above the remote pressure port 22 . Specifically, the pressure (P) at the remote pressure port 22 is a function of P=ρ*g*h, where ρ=density of the liquid, g=acceleration of gravity, and h=height of the liquid above the remote pressure port 22.

If this determination is made, the extracorporeal blood treatment apparatus 1 may be configured to provide an indication to the operator in the form of an alarm or other signal and, in one or more embodiments, may also result in an operative connection to the control unit Operation of one or more pumps is terminated. In addition, if the extracorporeal blood treatment device includes a valve, clamp, etc. ).

The control unit used in the extracorporeal blood treatment apparatus described herein may be arranged in any suitable form and may eg comprise a memory and a controller. The controller may, for example, be in the form of one or more microprocessors, application specific integrated circuit (ASIC) state machines, or the like. The control unit may include one or more any suitable input device (e.g., keyboard, touch screen, mouse, trackball, etc.) configured to allow a user to operate the device, and a display device (e.g., monitor (which may or may not be a touch screen), indicator lights, etc.).

Another alternative exemplary embodiment of an extracorporeal blood treatment device 101 is shown in FIG. 3 . Among the components forming part of the extracorporeal blood treatment device 101 shown in the schematic diagram of FIG. Inside. The extracorporeal blood treatment device 101 shown in FIG. 3 also includes a liquid collector 120 positioned and dimensioned to collect liquid leaking from the fluid circuit within the extracorporeal blood treatment device 101 .

Pressure sensor 128 includes two local pressure ports 126a and 126b. The first remote pressure port 122a is connected to a local pressure port 126a on the pressure sensor 128 through a fluid-filled pressure line 124a, while the second remote pressure port 122b is connected to the local pressure port 126a on the pressure sensor 128 through a second fluid-filled pressure line 124b. Pressure port 126b.

The first remote pressure port 122a is positioned in the liquid collector 122 to detect the pressure exerted on the remote pressure port 122a by the liquid collected in the liquid collector 120 . The second remote pressure port 122b is open to atmospheric pressure. In one or more embodiments, the second remote pressure port 126b is positioned at the same height h as the first remote pressure port 122a relative to the local pressure ports 126a and 126b. Doing so allows the system to both correct for atmospheric pressure changes and eliminate the pressure head created by the fluid in fluid-filled lines 124a and 124b. It should be noted that relative positional terms used herein, such as "above", "below" and "height" are measured along the direction of gravity.

Although in the depicted embodiment local pressure ports 126a and 126b are part of a single pressure sensor 128, in one or more alternative embodiments, each local pressure port may be connected to a separate and independent pressure sensor, wherein Each individual pressure sensor is operatively connected to the control unit 130 .

Although the method of detecting a leak in an extracorporeal blood processing device has been described in relation to the device shown in FIGS. 1-3 , one or more embodiments of the method of detecting a leak in an extracorporeal blood processing device described herein may include A liquid circuit located on or in the housing of the extracorporeal blood treatment device pumps liquid. As described herein, the fluid circuit may include one or more pumps and tubing configured to perform extracorporeal blood treatment. Liquid leaking from the liquid circuit may be collected in a liquid collector located below the housing of the extracorporeal blood treatment device.

In one or more embodiments, the methods may include detecting the pressure applied to the remote pressure port of the pressure sensor by liquid collected in the liquid collector. The pressure sensor is located on or in the housing and the remote pressure port is located at a selected location in the liquid collector. The pressure applied on the remote pressure port is transferred to the local pressure port of the pressure sensor using a pressure line extending from the remote pressure port to the local pressure port. A pressure line transfers pressure from the remote pressure port to the local pressure port through fluid located in the pressure line.

The method further includes determining that liquid has leaked from the liquid circuit when the pressure exerted by the liquid collected in the leak collector on the remote pressure port reaches or exceeds a selected pressure limit.

In one or more alternative embodiments of the method of detecting a leak as described herein, detecting the pressure exerted by the leaking liquid collected in the liquid collector may include detecting the pressure exerted by the liquid collected in the liquid collector. Pressure on the sensor's first remote pressure port. The pressure sensor is located on or in the housing of the extracorporeal blood treatment device. A first remote pressure port is located at a first selected location in the liquid collector. The pressure detected at the first remote pressure port is communicated to the first local pressure port of the pressure sensor using a first pressure line extending from the first remote pressure port to the first local pressure port. The first pressure line communicates pressure from the first remote pressure port to the first local pressure port through fluid located in the first pressure line.

The method may also include sensing atmospheric pressure applied to a second remote pressure port connected to a second local pressure port of the pressure sensor by a second fluid-filled line. As a result, the pressure applied to the first remote pressure sensor can be adjusted to account for changes in atmospheric pressure. In one or more embodiments, the second remote pressure port may be positioned at the same elevation as the first pressure port relative to the local pressure port on the pressure sensor. As a result, the pressure applied to the first remote pressure port can also be adjusted for the head pressure due to fluid in the fluid-filled pressure line connecting the first and second remote pressure ports to the pressure sensor .

A method involving pressure sensing on such first and second remote pressure ports includes determining that the liquid is coming from Leak in liquid circuit.

In one or more embodiments of the method of detecting a leak in a fluid circuit of an extracorporeal blood processing apparatus as described herein, the fluid in the pressure line for pressure transfer from the remote pressure port to the local port is substantially Composed of one or more gases.

In one or more embodiments of the method of detecting a leak in a fluid circuit of an extracorporeal blood processing apparatus as described herein, the fluid in the pressure line used to transfer pressure from the remote pressure port to the local pressure port is substantially Consists of one or more liquids.

In one or more embodiments of the method of detecting a leak in a fluid circuit of an extracorporeal blood treatment apparatus as described herein, the method may include: upon determining that fluid has leaked from the fluid circuit, stopping one or A pump of multiple pumps.

The complete disclosures of the patents, patent documents, and publications identified herein are hereby incorporated by reference in their entirety, as if each were individually incorporated.

Illustrative embodiments of blood processing apparatus and methods of using same have been discussed with reference to possible variations. These and other changes and modifications in the invention will be apparent to those skilled in the art without departing from the scope of the invention, and it should be understood that this invention is not limited to the exemplary embodiments set forth herein. Accordingly, the invention is to be limited only by the claims provided below and their equivalents.

Claims (15)

1. An extracorporeal blood treatment device, comprising: case; a fluid circuit on or in the housing, wherein the fluid circuit includes one or more pumps and tubing configured to move blood through the fluid circuit for extracorporeal blood treatment; a liquid collector configured to collect liquid leaking from the liquid circuit; wherein the liquid leaking from the liquid circuit reaches the liquid collector under the action of gravity; a pressure sensor comprising a local pressure port on or in the housing, a remote pressure port at a selected location in the liquid collector, and a pressure sensor extending from the remote pressure port to the local pressure port. The pressure line of the port where the liquid collected by the collector accumulates above the selected location, wherein the local pressure port is positioned in the liquid collector such that the selected location in the liquid collector Liquid collected at the location contacts the remote pressure port, and wherein the pressure line is configured to transfer pressure exerted on the remote pressure port to the local pressure line via fluid located in the pressure line pressure ports; and a control unit operatively connected to the pressure sensor, wherein the control unit is configured to: receiving a signal from the pressure sensor, wherein the signal is indicative of pressure sensed by a remote pressure port of the pressure sensor; and A determination is made that fluid is leaking from the fluid circuit when the pressure sensed by the remote pressure port reaches or exceeds a selected pressure limit. 2. The apparatus of claim 1, wherein the pressure line is connected to the remote pressure port by a fluid tight connector. 3. Apparatus according to claim 1 or 2, wherein the pressure line is connected to the local pressure port by a fluid tight connector. 4. Apparatus according to any one of claims 1 to 3, wherein the fluid in the pressure line consists essentially of one or more gases. 5. Apparatus according to any one of claims 1 to 3, wherein the fluid in the pressure line consists essentially of one or more liquids. 6. Apparatus according to any one of claims 1 to 5, wherein the pressure sensor comprises: a second remote pressure port configured to measure barometric pressure at a second selected location; and a second pressure line extending from the second remote pressure port to a second local pressure port of the pressure sensor, wherein the second pressure line is configured to be applied to the second remote pressure port the pressure of is delivered to the second local pressure port via fluid in the second pressure line; And wherein the control unit is configured to make a leak of liquid from the liquid circuit when the difference in pressure sensed by the remote pressure port and the second remote pressure port reaches or exceeds a selected value judgment. 7. The apparatus of claim 6, wherein the second selected location is positioned at a selected height relative to the second local pressure port, and wherein a selected location in the liquid collector The remote pressure port at the location is also at the selected height relative to the local pressure port to which it is connected. 8. Apparatus according to any one of claims 6 to 7, wherein the fluid in the second pressure line consists essentially of one or more gases. 9. Apparatus according to any one of claims 6 to 7, wherein the fluid in the second pressure line consists essentially of one or more liquids. 10. Apparatus according to any one of claims 1 to 9, wherein the control unit is operatively connected to a pump of the one or more pumps of the liquid circuit, and wherein the control unit is controlled by configured to stop the operation of the pump when the control unit determines that the liquid circuit is leaking. 11. A method of detecting leaks in an extracorporeal blood treatment device, the method comprising: pumping the fluid through a fluid circuit on or in the housing, the fluid circuit comprising one or more pumps and tubing configured to perform extracorporeal blood treatment; collecting liquid leaking from the liquid circuit in a liquid collector located below the housing; detecting pressure exerted by liquid collected in the liquid collector on a remote pressure port of a pressure sensor, wherein the pressure sensor is located on or in the housing, and wherein the remote pressure a port is located at a selected location in said liquid collector; The pressure detected at the remote pressure port is communicated to the local pressure port using a pressure line extending from the remote pressure port to the local pressure port of the pressure sensor, wherein the pressure line transfers the pressure from the remote pressure port communicates to the local pressure port via fluid in the pressure line; and A determination is made that fluid is leaking from the fluid circuit when the pressure sensed by the remote pressure port reaches or exceeds a selected pressure limit. 12. A method of detecting leaks in an extracorporeal blood treatment device, the method comprising: pumping the fluid through a fluid circuit on or in the housing, the fluid circuit comprising one or more pumps and tubing configured to perform extracorporeal blood treatment; collecting liquid leaking from the liquid circuit in a liquid collector located below the housing; detecting pressure exerted by liquid collected in the liquid collector on a first remote pressure port, wherein the first remote pressure port is located at a first selected location in the liquid collector, and wherein, liquid collected by the collector accumulates above the first remote pressure port; The pressure detected at the first remote pressure port will be detected at the first remote pressure port using a first pressure line extending from the first remote pressure port to a first local pressure port of a pressure sensor located on or in the housing. pressure to the first local pressure port, wherein the first pressure line transmits the pressure from the first remote pressure port to the first pressure port via fluid in the first pressure line local pressure port; detecting atmospheric pressure acting on the second remote pressure port; communicating atmospheric pressure detected at the second remote pressure port to the second local pressure port using a second pressure line extending from the second remote pressure port to a second local pressure port of the pressure sensor , wherein the second pressure line transfers pressure from the second remote pressure port to the second local pressure port via fluid located in the second pressure line; and A determination is made that fluid is leaking from the fluid circuit when the difference in pressure sensed by the first remote pressure port and the second remote pressure port reaches or exceeds a selected value. 13. The method of claim 12, the second remote pressure port being positioned at a selected height relative to the second local pressure port, and wherein the first remote pressure port is also positioned relative to the second local pressure port said selected height of said first local pressure port. 14. A method according to any one of claims 11 to 13, wherein the fluid in the pressure line consists essentially of one or more gases. 15. The method according to any one of claims 11 to 14, wherein the method further comprises stopping pumping in one or more pumps in the liquid circuit after determining that liquid has leaked from the liquid circuit. Pump.