Patent Description:
The present disclosure generally relates to pumping segments, and, in particular, to peristaltic pumping segments.

Patients in hospitals often receive medications and medical fluids (e.g., a saline solution or a liquid medication) via infusion using an intravenous ("IV") pump. In some applications, an IV pump uses peristaltic manipulation of a segment of tubing of an IV set to create the flow of medical fluid to the patient. Peristaltic manipulation of a segment of tubing may utilize the material properties of the tubing during operation. Document <CIT> discloses a biological component-measuring device enabling the operator to calibrate the entire device and capable of measuring biological components accurately. The device measures a sample including a body fluid taken through a body fluid sampler by sending it with a pump through a sample channel to a sensor.

In some applications, the material properties of the tubing may limit the fluid delivery accuracy of a peristaltic pump.

The disclosed subject matter relates to pumping segments in combination with a peristaltic pump as defined in the accompanying claims. In certain embodiments, a peristaltic pumping segment include a tubing segment, a plunger, an occluder, and a check valve. The tubing segment defines a pumping volume between an upstream portion and a downstream portion. The plunger is disposed adjacent to the pumping volume of the tubing segment. The plunger is movable to selectively expand the pumping volume to draw in fluid flow and contract the pumping volume to administer the fluid flow. The occluder is disposed adjacent to the downstream portion of the tubing segment. The occluder is movable to selectively engage against the downstream portion to prevent fluid flow from the downstream portion during expansion of the pumping volume and to permit fluid flow from the pumping volume through the downstream portion during contraction of the pumping volume. The check valve is coupled to the upstream portion of the tubing segment, the check valve comprising a valve element in fluid communication with a valve inlet and a valve outlet. The valve outlet is in fluid communication with the pumping volume, and the valve element is configured to permit fluid flow from the valve inlet to the pumping volume during expansion of the pumping volume and to prevent fluid flow from the pumping volume to the valve inlet during contraction of the pumping volume.

In certain embodiments, a fluid delivery system includes a fluid container including a medical fluid, an intravenous tubing, and an intravenous pump. The intravenous pump includes a tubing segment, a plunger, an occluder, and a check valve. The tubing segment defines a pumping volume between an upstream portion and a downstream portion, wherein the downstream portion is in fluid communication with the intravenous tubing. The plunger is disposed adjacent to the pumping volume of the tubing segment. The plunger is movable to selectively expand, or permit expansion of, the pumping volume to draw in the medical fluid from the fluid container and contract the pumping volume to administer the medical fluid to the intravenous tubing. The occluder is disposed adjacent to the downstream portion of the tubing segment. The occluder is movable to selectively engage against the downstream portion to prevent fluid flow from the intravenous tubing during expansion of the pumping volume and to permit fluid flow from the pumping volume through the intravenous tubing during contraction of the pumping volume. The check valve is coupled to the upstream portion of the tubing segment, the check valve comprising a valve element in fluid communication with a valve inlet and a valve outlet. The valve inlet is in fluid communication with the fluid container, the valve outlet is in fluid communication with the pumping volume, and the valve element is configured to permit fluid flow from the fluid container to the pumping volume during expansion of the pumping volume and to prevent fluid flow from the pumping volume toward the fluid container during contraction of the pumping volume.

In certain embodiments, a method is disclosed and comprises expanding a pumping volume of a tubing segment; and drawing a medical fluid through a check valve into the pumping volume during the expanding the pumping volume.

The detailed description set forth below is intended as a description of various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology may be practiced. Like components are labeled with identical element numbers for ease of understanding. Reference numbers may have letter suffixes appended to indicate separate instances of a common element while being referred to generically by the same number without a suffix letter.

While the following description is directed to administration of medical fluid by utilizing the disclosed peristaltic pumping segment, it is to be understood that this description is only an example of usage and does not limit the scope of the claims. Various aspects of the disclosed peristaltic pumping segments may be used in any application where it is desirable to administer the flow of fluid.

<FIG> depicts a patient <NUM> receiving an infusion of a medical fluid using an IV pump <NUM>. In the depicted example, the IV pump <NUM> is delivering a medical fluid from a fluid container <NUM> to the patient <NUM>. A fluid container <NUM> is hung at or above the patient's head and connected via an IV set <NUM> to the IV pump module <NUM> and then to the patient <NUM>. In some embodiments, the IV pump <NUM> includes a control unit <NUM> and a pumping module <NUM>.

The pumping module <NUM> can include a peristaltic pump segment to administer the medical fluid from the fluid container <NUM> to the patient <NUM>.

<FIG> is an illustration of a peristaltic pump segment <NUM> in a filling phase, in accordance with various aspects of the present disclosure. As illustrated, a peristaltic pump segment <NUM> can include tubing <NUM> that is peristaltically manipulated to create the flow of medical fluid to the patient. In some embodiments, an upstream portion <NUM> of the tubing <NUM> is in fluid communication with a source of medical fluid, such as an IV bag or other medical fluid container, and the downstream portion <NUM> of the tubing is in fluid communication with IV tubing to the patient.

In some embodiments, peristaltic pumping repeatedly cycles between a filling phase and a delivery phase.

In some applications, a peristaltic pump segment <NUM> can include a plunger <NUM>, an upstream occluder <NUM>, and a downstream occluder <NUM>, each configured to contact and manipulate the tubing <NUM> to deliver fluid from a fluid source to the patient. In some embodiments, the plunger <NUM>, the upstream occluder <NUM>, and the downstream occluder <NUM> can move in coordinated, sequential steps to pump fluid through the tubing <NUM>. The tubing <NUM> can be formed from a mechanically resilient material such as polyvinyl chloride (PVC), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), polyolefin, silicone, composites thereof, or the like.

With reference to <FIG>, the tubing <NUM> draws in medical fluid <NUM> during the filling phase. As illustrated, the plunger <NUM> is withdrawn or retracted from a compressed portion of the tubing <NUM>, allowing the tubing walls <NUM> to resiliently expand the pumping volume <NUM> to an original or expanded state. The plunger <NUM> can be moved by a suitable mechanism, including one or more of an actuator, a cam assembly, a geared assembly, or the like.

In the depicted example, the expansion of the pumping volume <NUM> draws in fluid into the peristaltic pump segment <NUM>, and in particular, the pumping volume <NUM>. The mechanical resilience of the tubing <NUM> allows the tubing walls <NUM> to expand from a compressed state to an expanded state, expanding the pumping volume <NUM>. The rate at which the pumping volume <NUM> rebounds from a compressed state to an expanded state can determine the amount of fluid that can be drawn into the pumping volume <NUM> in a given period of time.

As illustrated, during the expansion of the pumping volume <NUM>, the downstream portion <NUM> of the tubing <NUM> is blocked, pinched, or otherwise occluded by the downstream occluder <NUM> to prevent backflow or contamination of fluid into the pumping volume <NUM>.

In the depicted example, the downstream occluder <NUM> is actuated, moved downward, or otherwise engaged to compress the tubing walls <NUM> of the tubing <NUM> at the downstream portion <NUM> to occlude flow through the downstream portion <NUM> of the tubing <NUM>. The downstream occluder <NUM> can be moved by any suitable mechanism, including an actuator, a cam assembly, a geared assembly, etc. The downstream occluder <NUM> can include a beveled engagement portion <NUM> to contact the tubing <NUM>. When engaged, the downstream occluder <NUM> can prevent flow or fluid communication from the downstream portion <NUM> into the pumping volume <NUM>.

During the expansion of the pumping volume <NUM>, medical fluid <NUM> is drawn into pumping volume <NUM> from the upstream portion <NUM> of the tubing <NUM>. As illustrated, during the expansion of the pumping volume <NUM>, the upstream portion <NUM> of the tubing <NUM> is unobstructed by the upstream occluder <NUM>, permitting medical fluid <NUM> into the pumping volume <NUM>. During operation, the upstream occluder <NUM> is withdrawn or retracted from a compressed portion of the tubing <NUM>, allowing the tubing walls <NUM> to resiliently expand the upstream portion <NUM> to an original or expanded state. The upstream occluder <NUM> can be moved by a suitable mechanism, including one or more of an actuator, a cam assembly, a geared assembly, or the like.

In the depicted example, the expansion of the upstream portion <NUM> permits the flow of medical fluid <NUM> into the peristaltic pump segment <NUM>, and in particular, the pumping volume <NUM>. The mechanical resilience of the tubing <NUM> allows the tubing walls <NUM> to expand from a compressed state to an expanded state, expanding the cross-sectional profile or flow area of the upstream portion <NUM>. The rate at which the upstream portion <NUM> rebounds from a compressed state to an expanded state can limit the size of the flow area or opening into the pumping volume <NUM>. Therefore, the rate at which the upstream portion <NUM> rebounds from a compressed state to an expanded state can limit or restrict the amount of fluid that can be drawn into the pumping volume <NUM> in a given period of time.

The amount of medical fluid <NUM> drawn into the pumping volume <NUM> during the filling phase can be determined by the timing and sequence of the plunger <NUM>, the upstream occluder <NUM>, a viscosity of the medical fluid <NUM>, and the mechanical properties of the tubing <NUM>.

<FIG> is an illustration of a peristaltic pump segment <NUM> of <FIG> in a delivery phase, in accordance with various aspects of the present disclosure.

In the depicted example, the peristaltic pumping segment <NUM> delivers medical fluid through a downstream portion <NUM> to a downstream location, such as a patient. As illustrated, the plunger <NUM> is actuated, moved downward, or otherwise engaged to compress the tubing walls <NUM> of the tubing <NUM> to compress the pumping volume <NUM> to a compressed or reduced state.

During operation, the compression of the pumping volume <NUM> expels or otherwise administers fluid from the pumping volume <NUM> to a downstream location. The rate of administration of the medical fluid can be controlled by the force and velocity of the plunger <NUM>.

During administration, the upstream portion <NUM> of the tubing <NUM> is blocked, pinched, or otherwise occluded by the upstream occluder <NUM> to prevent inadvertent fluid flow into the pumping volume <NUM> and to prevent backflow of fluid into the medical container from the pumping volume <NUM>.

In the depicted example, the upstream occluder <NUM> is actuated, moved downward, or otherwise engaged to compress the tubing walls <NUM> of the tubing <NUM> at the upstream portion <NUM> to occlude flow through the upstream portion <NUM> of the tubing <NUM>. The upstream occluder <NUM> can include a beveled engagement portion <NUM> to contact the tubing <NUM>. When engaged, the upstream occluder <NUM> can prevent flow or fluid communication between the upstream portion <NUM> and the pumping volume <NUM>.

During the compression of the pumping volume <NUM>, medical fluid is forced from the pumping volume <NUM> to a downstream location through the downstream portion <NUM> of the tubing <NUM>. As illustrated, during the compression of the pumping volume <NUM>, the downstream portion <NUM> of the tubing <NUM> is unobstructed by the downstream occluder <NUM>, permitting medical fluid <NUM> to flow out of the peristaltic pumping segment <NUM>. During operation, the downstream occluder <NUM> is withdrawn or retracted from a compressed portion of the tubing <NUM>, allowing the tubing walls <NUM> to resiliently expand the downstream portion <NUM> to an original or expanded state.

In the depicted example, the expansion of the downstream portion <NUM> permits the flow of medical fluid <NUM> out of the peristaltic pump segment <NUM>, and in particular, the pumping volume <NUM>. The mechanical resilience of the tubing <NUM> allows the tubing walls <NUM> to expand from a compressed state to an expanded state, expanding the cross-sectional profile or flow area of the downstream portion <NUM>. The rate at which the downstream portion <NUM> rebounds from a compressed state to an expanded state can limit the size of the flow area or opening out of the pumping volume <NUM>. Therefore, the rate at which the downstream portion <NUM> rebounds from a compressed state to an expanded state can limit or restrict the amount of fluid that can flow out of the pumping volume <NUM> in a given period of time.

The amount of medical fluid <NUM> administered from the pumping volume <NUM> during the delivery phase can be determined by the timing and sequence of the plunger <NUM>, the downstream occluder <NUM> and the mechanical properties of the tubing <NUM>.

In some applications, it may be desirable to perform peristaltic pumping operations at high flow rates (up to <NUM>/hr) across a wide range of temperatures (<NUM> C to <NUM> C). As described herein, the upstream portion of the tubing may be required to rebound from a compressed state to an expanded state rapidly (in a sub-second time scale) to facilitate high flow rates. However, materials used for tubing (e.g., polyvinyl chloride (PVC), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), polyolefin, silicone, etc.) can become rigid at lower temperatures and deteriorate in elasticity. Therefore, the upstream portion of the tubing may rebound from a compressed state to an expanded state at a slower rate than required to facilitate high flow rates. In some applications, the amount of fluid drawn into the pumping volume of the tubing during expansion may be reduced at low temperatures, resulting in under volume delivery.

In some applications, it may be desirable to perform peristaltic pumping operations at low flow rates (as low as <NUM>/hr) across a wide range of temperatures (<NUM> C to <NUM> C). As described herein, the upstream portion of the tubing may be required to rebound from a compressed state to an expanded state slowly to facilitate low flow rates. However, PVC tubing may exhibit surface tackiness due to exuded small molecular plasticizers on the inner and outer layer surface of the tubing, which may cause the tubing walls to adhere together at higher temperatures. Therefore, the upstream portion of the tubing may rebound from a compressed state to an expanded state at a slower rate than required or may remain in a compressed or occluded state. In some applications, the amount of fluid drawn into the pumping volume of the tubing during expansion may be reduced at low flow rates at high temperatures, resulting in under volume delivery.

The disclosed peristaltic pump segment incorporates a check valve to allow for improved fluid delivery accuracy. By utilizing a check valve in the peristaltic pump segment, the peristaltic pump segment can provide consistent and accurate fluid delivery by reducing or eliminating undesired flow caused by unpredictable rebounding of the segment, which may vary based on temperature and pumping frequency.

The disclosed peristaltic pumping segment overcomes several challenges discovered with respect to certain conventional peristaltic pumping segments and systems. One challenge with certain conventional peristaltic pumping segment is that certain conventional peristaltic pumping segment rely on the material properties of the tubing to draw fluid volume into the pumping segment. Further, certain peristaltic pumping segments or systems may require numerous moving parts during operation such as occluders to control the flow of fluid from a source to a patient. Because material properties of tubing may vary with temperature and pumping frequency, decreasing accuracy, and numerous moving parts can increase complexity, power consumption, and wear, it is advantageous to provide peristaltic pumping segments and systems, as described herein, that allow for increased fluid delivery accuracy, less wear on the tubing, fewer mechanical parts, and lower power consumption. The disclosed peristaltic pumping segments provide for increased fluid delivery accuracy, less wear on the tubing, fewer mechanical parts, and lower power consumption.

Examples of peristaltic pumping segments that allow for increased fluid delivery accuracy and reduced complexity are now described.

<FIG> is an illustration of a peristaltic pump segment <NUM> in a filling phase, in accordance with various aspects of the present disclosure. As illustrated, a peristaltic pump segment <NUM> can include tubing <NUM> that is peristaltically manipulated to create the flow of medical fluid to the patient. As described herein, the flow of medical fluid is controlled by a check valve <NUM> coupled to the tubing <NUM>. In some embodiments, a valve inlet <NUM> of the check valve <NUM> is in fluid communication with a source of medical fluid, such as a medical fluid container. The valve outlet <NUM> of the check valve <NUM> is in fluid communication with a pumping volume <NUM> of the tubing <NUM>. In some embodiments, the downstream portion <NUM> of the tubing <NUM> is in fluid communication with IV tubing to the patient.

In some embodiments, peristaltic pumping cycles between a filling phase and a delivery phase.

In some applications, a peristaltic pump segment <NUM> can include a plunger <NUM> and a downstream occluder <NUM> configured to contact and manipulate the tubing <NUM> to deliver fluid from a fluid source to the patient. In some embodiments, the plunger <NUM> and the downstream occluder <NUM> can move in coordinated, sequential steps to pump fluid through the tubing <NUM>. The check valve <NUM> can control flow through the tubing <NUM> during the pumping process to allow flow from a medical fluid source into the tubing <NUM>, while preventing backflow from the tubing <NUM> into the medical fluid source. The tubing <NUM> can be formed from a mechanically resilient material such as polyvinyl chloride (PVC), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), polyolefin,, silicone, composites thereof, or the like.

The features shown in <FIG> also reduce the need for an upstream occluder, such as the occluder <NUM> shown in <FIG>. If the pumping segment includes an in-line valve as described and shown, for example, in <FIG>, the pump may omit the upstream occluder along with the complexities and resource management required to adjust the functioning thereof. For example, additional power and processing cycles may be needed to control the upstream occluder. Use of these resources along with friction associated with, for example, pressing against the tubing may increase the temperature thereby introducing the potential for additional rebound effects.

In some implementations, the pump may selectively enable an upstream occluder based on the set loaded into the pump. For example, the set may include an identifier that can be detected upon insertion to the pump. In some implementations, the pump may request a user input during programming to identify the set being loaded. If the set is identified as a type with the in-line check valve features described, the pump may disable the upstream occluder to reduce resources needed for the infusion and strain on the pumping segment. By disabling the upstream occluder, the sources of temperature variance may be reduced. However, if the set is identified as a type without the in-line features described, the pump may enable the upstream occluder.

With reference to <FIG>, the tubing <NUM> draws in medical fluid <NUM> during the filling phase. As illustrated, the plunger <NUM> is withdrawn or retracted from a compressed portion of the tubing <NUM>, allowing the tubing walls <NUM> to resiliently expand the pumping volume <NUM> to an original or expanded state. As can be appreciated, the plunger <NUM> can be moved by a suitable mechanism, including one or more of an actuator, a cam assembly, a geared assembly, or the like.

In the depicted example, the expansion of the pumping volume <NUM> draws in fluid into the peristaltic pump segment <NUM>, and in particular, the pumping volume <NUM>. As can be appreciated, the mechanical resilience of the tubing <NUM> allows the tubing walls <NUM> to expand from a compressed state to an expanded state, expanding the pumping volume <NUM>. The rate at which the pumping volume <NUM> rebounds from a compressed state to an expanded state can determine the amount of fluid that can be drawn into the pumping volume <NUM> in a given period of time.

In the depicted example, the downstream occluder <NUM> is actuated, moved downward, or otherwise engaged to compress the tubing walls <NUM> at the downstream portion <NUM> to occlude flow through the downstream portion <NUM> of the tubing <NUM>. The downstream occluder <NUM> can be moved by a suitable mechanism, including one or more of an actuator, a cam assembly, a geared assembly, or the like. The downstream occluder <NUM> can include a beveled engagement portion <NUM> to contact the tubing <NUM>. When engaged, the downstream occluder <NUM> can prevent flow or fluid communication from the downstream portion <NUM> into the pumping volume <NUM>.

During the expansion of the pumping volume <NUM>, medical fluid <NUM> is drawn into pumping volume <NUM> through the check valve <NUM> coupled to the tubing <NUM>. As illustrated, during the expansion of the pumping volume <NUM>, the check valve <NUM> allows for medical fluid <NUM> to flow from the valve inlet <NUM> to the valve outlet <NUM>, permitting medical fluid <NUM> into the pumping volume <NUM>. During operation, a valve element within the check valve <NUM> is actuated or moved to permit flow from the valve inlet <NUM> toward the valve outlet <NUM>. In some implementations, the valve element can be spring actuated, or passively actuated with using a flap, ball and socket, or other means to fluid to flow only one direction.

In the depicted example, the actuation of the valve element within the check valve <NUM> to permit flow between the valve inlet <NUM> and the valve outlet <NUM> permits the flow of medical fluid <NUM> into the peristaltic pump segment <NUM>, and in particular, the pumping volume <NUM>. As can be appreciated, the valve element can be actuated by a pressure differential across the valve inlet <NUM> and the valve outlet <NUM>. For example, as the pumping volume <NUM> expands, the increasing volume of the pumping volume <NUM> can create a pressure differential across the valve inlet <NUM> and the valve outlet <NUM>, actuating the valve element and permitting flow into the pumping volume <NUM>. Optionally, positive pressure (e.g., by changing the height of the fluid container relative to the pump) can be applied at a fluid source to create a pressure differential across the valve inlet <NUM> and the valve outlet <NUM>.

In some embodiments, the check valve <NUM> can have a threshold pressure or cracking pressure that actuates the valve element to permit flow from the valve inlet <NUM> to the valve outlet <NUM>. Optionally, the cracking pressure can be selected based on flow requirements, temperature, tubing selection, etc. In some embodiments, the check valve <NUM> can have a valve element controlled by an actuator and/or a controller. The rate of actuation of the valve element from an occluding state to a flow state can control the amount of fluid that can be drawn into the pumping volume <NUM> in a given period of time. Advantageously, the valve element of the check valve <NUM> can be rapidly actuated independent of the mechanical properties (e.g. resilience) of the tubing <NUM>, allowing the check valve <NUM> to permit a desired amount of fluid into the pumping volume <NUM> independent of temperature, tubing material, and/or flow rates.

The amount of medical fluid <NUM> drawn into the pumping volume <NUM> during the filling phase can be determined by the timing and sequence of the plunger <NUM>, the characteristics of the check valve <NUM> and the mechanical properties of the tubing <NUM>.

During administration, the flow through the check valve <NUM> is blocked or occluded to prevent inadvertent fluid flow into the pumping volume <NUM> and to prevent backflow of fluid from the pumping volume <NUM> back into the medical container. During administration, the check valve <NUM> prevents or restricts the backflow of medical fluid from the valve outlet <NUM> toward the valve inlet <NUM>. The check valve <NUM> further prevents or restricts inadvertent flow of medical fluid from the valve inlet <NUM> to the valve outlet <NUM>.

The valve element can be configured to remain in an occlusion position when a pressure differential is applied across the valve outlet <NUM> and the valve inlet <NUM>. For example, when the pumping volume <NUM> is moved to a compressed configuration, the valve element can prevent the backflow of fluid from the valve outlet <NUM> toward the valve inlet <NUM>.

The valve element can be configured to remain in an occlusion position in the absence of a pressure differential. For example, when the pumping volume <NUM> is at a resting or expanded configuration, the valve element can prevent the backflow of fluid from the valve outlet <NUM> toward the valve inlet <NUM>. Further, the valve element can be configured to remain in an occlusion position if a pressure differential across the valve inlet <NUM> and the valve outlet <NUM> does not exceed the cracking pressure of the check valve <NUM>. For example, the valve element can prevent the inadvertent flow of medical fluid into the pumping volume <NUM> when the pumping volume <NUM> is in a resting (e.g., expanded) position.

In some embodiments, the downstream occluder <NUM> can be replaced with a check valve. A downstream check valve can be configured to have a cracking pressure to permit desired outflow from the pumping volume <NUM> while preventing backflow from downstream locations.

In some applications, the peristaltic pump segment <NUM> can be utilized in pump modules configured for use with upstream occluders and downstream occluders by disabling operation of the upstream occluder.

Terms such as "top," "bottom," "front," "rear" and the like if used in this disclosure should be understood as referring to an arbitrary frame of reference, rather than to the ordinary gravitational frame of reference. Thus, a top surface, a bottom surface, a front surface, and a rear surface may extend upwardly, downwardly, diagonally, or horizontally in a gravitational frame of reference.

Various items may be arranged differently (e.g., arranged in a different order, or partitioned in a different way) all without departing from the scope of the subject technology. Furthermore, to the extent that the term "include," "have," or the like is used, such term is intended to be inclusive in a manner similar to the term "comprise" as "comprise" is interpreted when employed as a transitional word in a claim.

Claim 1:
A peristaltic pump including a peristaltic pump segment (<NUM>) that is configured to operate with the peristaltic pump, the pump segment (<NUM>) comprising:
a tubing segment (<NUM>) defining a resilient pumping volume (<NUM>) between an upstream portion and a downstream portion (<NUM>) of the tubing segment, the pumping volume being selectively engagable by a plunger (<NUM>) disposed adjacent to the pumping volume of the tubing segment, wherein the pumping volume is selectively engaged by the plunger to expand the pumping volume to draw fluid flow into the pumping volume and to contract the pumping volume to conduct fluid flow from the pumping volume; and
a check valve (<NUM>) coupled to the upstream portion of the tubing segment, the check valve comprising a valve element in fluid communication with a valve inlet (<NUM>) and a valve outlet (<NUM>), wherein the valve outlet is in fluid communication with the pumping volume, and the valve element is configured to permit fluid flow from the valve inlet to the pumping volume during expansion of the pumping volume and to prevent fluid flow from the pumping volume to the valve inlet during contraction of the pumping volume, and characterized in that:
the peristaltic pump comprises a disabled upstream occluder or an omitted upstream occluder.