Peristaltic pump of an infusion system for delivery of small volumes of fluid

A medical fluid infusion system includes a peristaltic pump system configured to deliver a fluid drug to a patient. The peristaltic pump system can include a peristaltic pump in communication with a pressure source. In some embodiments, the peristaltic pump system can include a valve body positioned between the peristaltic pump and pressure source for controlling the delivery of pressurized fluid (e.g., air, liquid) to the peristaltic pump. The peristaltic pump can include more than one occluder, with each occluder having a flexible member that can form a collapsed and extended configuration based on a pressure provided to the flexible member.

TECHNICAL FIELD

The subject matter described herein relates to peristaltic pumps and peristaltic pump systems, as well as related methods.

BACKGROUND

There are a variety of applications where it is advantageous to deliver small, precise volumes of fluid. For example, the delivery of various medicaments (e.g., pain medication, insulin, etc.) are delivered from various medical devices where the delivery of such medicaments are preferably delivered in small, precise volumes to the patient. Some devices can include a peristaltic pump configured to control the delivery of the small, precise volumes. However, although peristaltic pumps can be beneficial for delivering small and precise volumes of fluids, they can be costly to manufacture and maintain. For example, peristaltic pumps can include a variety of mechanical parts, such as gears, cams, and followers that assist in the delivery of the small, precise volumes of fluids. Such mechanical parts can experience frictional forces that wear the mechanical parts down over time, which may cause the peristaltic pump to not perform as efficiently or effectively. As a result, it can be time-consuming and expensive to fix or replace the defective peristaltic pump or, alternatively, can require replacement of the entire peristaltic pump, which can also be costly. As such, there is a need for improved peristaltic pumps for the delivery of small, precise volumes of fluid.

SUMMARY

Aspects of the current subject matter can include various embodiments of a peristaltic pump and/or peristaltic pump system. In one aspect, a peristaltic pump of a medical infusion system is described that can include a housing having a fluid line passageway configured to allow a flexible tubing to extend therealong. The peristaltic pump can further include more than one tubing occluder coupled to the housing and positioned adjacent the fluid line passageway. Each of the more than one tubing occluders can have a pressure connecting end configured to communicate with a pressure source and a flexible member configured to form a collapsed configuration when a pressure within the flexible member is below a first pressure. In addition, the flexible member can form an extended configuration when the pressure within the flexible member is above a second pressure thereby causing the flexible member to extend into the fluid line passageway for pinching the flexible tubing.

In another aspect, a peristaltic pump of a medical infusion system is described that can include more than one tubing occluder. Each of the more than one tubing occluder can include a base configured to couple to a housing having a fluid line passageway for allowing a flexible tubing to extend therealong. The base can include a pressure connecting end configured to couple to a fluid line extending between the peristaltic pump and the pressure source. Each of the more than one tubing occluder can further include a flexible member configured to form a collapsed configuration when a pressure within the flexible member is below a first pressure. The flexible member can form an extended configuration when the pressure within the flexible member is above a second pressure thereby allowing the flexible member to extend into the fluid line passageway.

In some variations one or more of the following features can optionally be included in any feasible combination. The peristaltic pump can include an occluding end of the flexible member that is positioned adjacent a base of the occluder when the flexible member is in the collapsed configuration. The occluding end can be positioned a distance away from a base of the occluder when in the extended configuration. The peristaltic pump can include a first occluder of the more than one fluid line occluders that includes a first flexible member having an angled occluding end. The flexible member can be made out of a rubber material. The pressure source can be an air pump or a hydraulic pump. The more than tubing occluders can be positioned along a length of the fluid line passageway and can be configured to form the extended and collapsed configurations to cause a volume of fluid to be advanced along the flexible tubing.

In yet another aspect, a peristaltic pump system of a medical infusion system is described that can include a pressure source and a peristaltic pump having more than one tubing occluder. Each of the more than one tubing occluder can include a base configured to couple to a housing having a fluid line passageway for allowing a flexible tubing to extend therealong. The base can include a pressure connecting end configured to couple to a fluid line extending between the peristaltic pump and the pressure source. In addition, the peristaltic pump can include a flexible member configured to form a collapsed configuration when a pressure within the flexible member is below a first pressure. The flexible member can form an extended configuration when the pressure within the flexible member is above a second pressure thereby allowing the flexible member to extend into the fluid line passageway.

In some variations one or more of the following features can optionally be included in any feasible combination. The peristaltic pump system can include a valve body positioned along the fluid line for controlling the delivery of pressurized fluid to one or more of the more than one tubing occluders. The pressure source can be an air pump or a hydraulic pump. The valve body can include more than one valve, and each of the more than one valves can be configured to control the delivery of pressurized fluid from the pressure source to a respective tubing occluder of the more than one tubing occluders.

In another interrelated aspect of the current subject matter, a method of pumping fluid through a peristaltic pump of a medical infusion system is described. The method can include increasing a pressure in a flexible member of a tubing occluder of a peristaltic pump thereby causing the flexible member to form an extended configuration and apply a force against a flexible tubing thereby pinching the flexible tubing. In addition, the method can include decreasing the pressure in the flexible member of the tubing occluder thereby causing the flexible member to form a collapsed configuration and release the force against the flexible tubing.

In some variations one or more of the following features can optionally be included in any feasible combination. The method can further include controlling a valve positioned along a fluid line extending between the peristaltic pump and a pressure source. The controlling of the valve can include allowing a pressurized fluid to flow from the pressure source to the flexible member to cause the increase in the pressure and preventing the pressurized fluid flow from the pressure source to the flexible member to cause the decrease in the pressure.

DETAILED DESCRIPTION

Described herein are medical fluid infusion systems including a pump system configured to deliver a fluid drug to a patient. The pump system includes a compact and modular fluid controlled peristaltic pump that is configured to advance small, precise volumes of fluid along a fluid line, such as for delivery to the patient.

FIG. 1Ashows a schematic representation of a fluid infusion system10. The fluid infusion system10is described herein in the context of being a bedside fluid drug infusion system for a patient although it should be appreciated that the features described herein may be used with any of a variety of fluid pumping systems and are not limited to drug infusion systems. In addition, the pump system described herein can be used for non-infusion devices.

With reference toFIG. 1A, the infusion system10includes a fluid container, such as an intravenous (IV) bag11, fluidly coupled to a patient via one or more fluid conduits, such as tubes12and14. A pump device15, such as a peristaltic pump, may drive fluid from the IV bag11toward the patient. The IV bag11contains a supply of fluid (such as a liquid drug or any other fluid) to be pumped to a patient. The pump device15is configured to pump fluid from the IV bag11toward a patient via a tube14. In an embodiment, the pump device15includes a disposable IV set that removably couples with the pump device, such as the Alaris® System from Becton Dickinson (San Diego, Calif.).

With reference still toFIG. 1A, the tube12has a proximal end fluidly coupled to the IV bag11, such as via the drip chamber. A distal end of the tube12is fluidly coupled to the pump device15. Likewise, the tube14has a proximal end fluidly coupled to a fluid lumen of the pump device15and a distal end that attaches to the patient via an IV connection. Either of the tubes12or14may be formed of a single tube (e.g., that extends through the pump device15) or may be formed of a series of tubes removably attached to one another, such as in an end-to-end manner using any of a variety of connectors such as Luer connectors. The tubes12and14provide a fluid pathway from the IV bag11toward the patient. This continuous fluid lumen may include any of a variety of components that facilitate or otherwise are used in connecting the tubes and/or pumping fluid, including, for example, valves, filters, free-flow stop valves, pressure and air detection regions or components and access connectors, etc. Any of a variety of additional components may be used, including, for example, anti-free flow devices, pressure sensing components, air detection components, etc.

Various embodiments of a peristaltic pump having more than one tubing occluder that can be positioned adjacent a fluid passageway are disclosed herein. The fluid passageway can be configured to allow a flexible fluid line to extend therealong and the peristaltic pump can be configured to control advancing of small, precise volumes of fluid along from the fluid line, such as for dispensing the small, precise volumes of fluid to a patient. In some embodiments, the peristaltic pump can include a plurality of tubing occluders that each include a flexible member configured to form collapsed and extended configurations depending upon a pressure provided within the flexible member. For example, when the pressure is increased within the flexible member, the flexible member can form an extended configuration. When in the extended configuration, the flexible member can extend approximately perpendicular to the fluid pathway such that the flexible member can pinch the fluid line at a location adjacent the flexible member. When the fluid line is pinched, an inner lumen of the fluid line can be closed thereby occluding the fluid line and preventing fluid flow at the pinched location. When in a collapsed configuration, the flexible member can be folded or collapsed into a base of the occluder thereby allowing the inner lumen of the fluid line to be open such that fluid can flow past the occluder with the collapsed flexible member.

Some embodiments of the peristaltic pump disclosed herein can include more than one occluder, such as three occluders that can each be caused to form extended and collapsed configurations in at least one sequence to cause small, precise volumes of fluid to be dispensed from the fluid line. In some embodiments of the peristaltic pump, at least one of the occluders can include a feature that assists with advancing fluid along the fluid line.

Some embodiments of the peristaltic pump disclosed herein can include one or more pressure coupling features that allow the peristaltic pump to be in fluid communication with a pressure source, such as a pulse width modulated (PWM) pump. For example, the pressure source can provide pressurized fluid to the peristaltic pump for causing one or more flexible members to form extended configurations. In some embodiments, the peristaltic pump can be configured to couple to one or more of a hydraulic pump and a hydroelectric pump that delivers pressurized liquid or air, respectively, to the peristaltic pump.

Embodiments of the peristaltic pump disclosed herein can be included in a peristaltic pump system that includes at least one peristaltic pump, pressure source, and a valve body. The valve body can include one or more valves configured to control the delivery of pressurized fluid (e.g., air, liquid) from the pressure source to the peristaltic pump. For example, the valve body can control the delivery of pressure to one or more occluders to cause associated flexible members to form extended configurations. As will be described in greater detail below, the valve body can control which occluders form extended and collapsed configurations to thereby control the delivery of small, precise volumes of fluid from the fluid line. The valve body can include any number of valves that can control the passage of pressurized fluid between a pressure source and embodiments of the peristaltic pump described herein. The valve body can be controlled mechanically and/or by any number of computer processing systems, such as a processing system that can control the valve body to deliver pressurized fluid to the occluders in one or more sequences.

Some embodiments of the peristaltic pump can include a housing having a fluid passageway configured to allow a flexible tubing or flexible fluid line to extend therealong. The housing can be part of the peristaltic pump or can be part of a device to which the peristaltic pump is coupled to. As such, in some embodiments, the peristaltic pump can include a housing that can be coupled to a device. In some embodiments, the peristaltic pump can include occluders that can be directly coupled to coupling features of a device. One advantage of the peristaltic pump embodiments described herein includes the modularity and ease of replacement and repair of the peristaltic pumps. For example, the occluders of the peristaltic pumps described herein can be easily coupled to and uncoupled from the housing and/or device. This can allow a user to efficiently and cost-effectively replace one or more occluders, such as an occluder that has become damaged. In some embodiments, the housing of the peristaltic pump can be releasably coupled to the device such that the entire peristaltic pump can be efficiently and cost-effectively replaced due, in part, to the compact and simplistic design of the peristaltic pump.

Embodiments of the peristaltic pump described herein include a number of improvements and benefits over the prior art. For example, the peristaltic pumps described herein do not include mechanical parts such as cams that can wear out over time and are expensive to repair/replace. Instead, the peristaltic pumps described herein include occluders with flexible members that can require less maintenance or replacement, as well as can be efficiently and cost-effectively replaced. The pressure source and/or valve body may also be replaced in a modular fashion. Various other improvements and benefits of the peristaltic pump embodiments disclosed herein are included in the scope of this disclosure.

FIG. 1Billustrates an embodiment of a peristaltic pump system100including a peristaltic pump102in communication with a pressure source104. As shown inFIG. 1, the peristaltic pump system100can include a valve body106positioned between the peristaltic pump102and pressure source104to control delivery of pressurized fluid (e.g., liquid, air) from the pressure source104to the peristaltic pump102. The peristaltic pump102can include a plurality of tubing occluders112in communication with the pressure source104via the valve body106. As will be described in greater detail below, controlled delivery of pressurized fluid from the pressure source104to one or more of the occluders112(via the valve body106) can cause the pressurized occluder(s)112to transition from a collapsed configuration to an extended configuration.

As shown inFIG. 1B, the peristaltic pump102can include a housing105having a fluid passageway108configured to allow a flexible fluid line110to extend therealong. The housing105can be a part of a device to which the peristaltic pump102is coupled to or the housing105can be configured to be releasably coupled to the device. The device can include any number of devices configured for delivering small, precise volumes of fluid, such as a device for delivering small, precise volumes of a medicament to a patient.

FIG. 2illustrates the peristaltic pump100with the plurality of occluders112in a collapsed configuration. As shown inFIG. 2the plurality of occluders112can include a first occluder112a, a second occluder112b, and a third occluder112c, with the first occluder112abeing furthest upstream relative to the direction of fluid flow passing through the peristaltic pump100. For example, when all of the occluders112are in the collapsed configuration, an inner lumen of the flexible tubing110extending along the fluid passageway108is not pinched such that fluid is allowed to free-flow past the plurality of occluders112. As will be described in greater detail below, sequencing the formation of extended and collapsed configurations between the plurality of occluders112can assist the peristaltic pump102with delivering small, precise volumes of fluid.

FIG. 3Ashows a cross-section view of the first tubing occluder112aof the peristaltic pump102in a collapsed configuration. As shown inFIG. 3Athe first tubing occluder112acan include a base120having an elongated hollow body121with a flange122at a proximal end for assisting with coupling and positioning the first tubing occluder112ato the housing105. The base120can include a pressure coupling feature124at a distal end that is configured to couple a pressure line for providing fluid communication between the pressure source104(via the valve body106) and the first tubing occluder112a. For example, the pressure coupling feature124can include threads, a quick-connect feature, or provide a sliding/friction fit for the pressure line to couple thereto. The base120can be rigid and/or flexible and can be made out of a variety of materials, including various types of rubber.

As shown inFIGS. 3A-3C, the first occluder112acan include a flexible member130made out a flexible material. The flexible member130can include an occluding end132and a base end134that connects the flexible member130to the base120. In some embodiments, as shown inFIG. 3B, the base end134of the flexible member130can be connected to the base120at or adjacent the flange122. The flexible member130can include an inner chamber135that is in fluid communication with at least the distal end of the body121. This can allow pressurized fluid delivered from the pressure source104to be directed into the inner chamber135of the flexible member130. The materials of the flexible member130and body121, as well as the connection between the flexible member130and base120, are such that pressurized fluid directed into the inner chamber135can cause the flexible member to deform, including stretch in one or more directions, from a collapsed configuration to an extended configuration.

For example, the flexible member130can be molded such that it includes a shape-memory of the collapsed configuration and thus returns to the collapsed configuration when pressure within the inner chamber135is at or below a first pressure level (e.g., atmospheric pressure). As pressure is increased in the inner chamber135(e.g., above a second pressure level), the pressure forces can overcome the spring memory molded into the flexible member130thereby causing the flexible member130to form the extended configuration. As such, when the pressure is reduced in the inner chamber135, the spring memory can cause the flexible member130to deform back to the collapsed configuration. Additionally, releasing the fluid retained in the inner chamber135to atmosphere (e.g., if the fluid is air) or to a reservoir (e.g., if the fluid is a liquid) can assist the flexible member130with transitioning from the extended configuration to the collapsed configuration. Such release of the fluid causes the pressure within the inner chamber135to reduce (e.g., below the first pressure level) thereby allowing the flexible member130to form the collapsed configuration.

As show inFIG. 3A, when the first tubing occluder112ais in the collapsed configuration, the flexible member130can be folded into the base134such that the occluding end132of the flexible member130is positioned adjacent the flange122, as shown inFIG. 3B. Additionally, in the collapsed configuration, a first length131of the flexible member130can extend down from the flange122along an inner wall of the body121to a folded portion137of the flexible member130, as shown inFIG. 3C. The folded portion137can allow a second length133of the flexible member130to extend up along the first length131of the flexible member130. As such, in the collapsed configuration, the occluding end132of the flexible member130can be positioned at or adjacent the proximal end of the base such that flexible member130does not pinch an adjacent fluid line. As shown inFIG. 3A, when the flexible member130is in the collapsed configuration, the first length131and the second length133of the flexible member130are approximately the same in length.

FIG. 4Aillustrates an embodiment of the first occluder112ain an extended configuration where the flexible member extends away from the base and the occluding end132is positioned a distance away from the base120. In the extended configuration, the flexible member130can cause pinching of an adjacent fluid line, as will be discussed in greater detail below. As shown inFIG. 4B, when the flexible member130is in the extended configuration, the first length131can be significantly shorter than the second length133of the flexible member130and the folded portion137can be positioned adjacent the proximal end of the base120.

The flexible member130can be made out of one or more of a variety of flexible materials and can include a variety of shapes and profiles. For example, the flexible member can have a circular, square, and/or rectangular shape or profile. Furthermore, in some embodiments, the second and third occluders112b,112ccan include the same or similar features as described above with respect to the first occluder112a. In some embodiments, any one of the plurality of occluders112can include one or more features that are not the same or similar compared to the other occluders112. For example, flexible members130of the first and third occluders112a,112ccan be the same or similar in shape and size such that they are optimized for pinching the flexible tubing and preventing fluid flow. In some embodiments, the flexible member130of the second occluder112bcan be sized and/or shaped different from the flexible member130of the first and second occluders112a,112csuch that the flexible member130of the second occluder112bis optimized for advancing fluid along the flexible tubing110.

In some embodiments, the flexible member130and the base120can be made out of the same material and/or formed as a single part. In some embodiments, the flexible member130and/or the base120can be made using one or more of a configurable thermoformed rubber, rotocuring, a blow molding process, and an injection molding process.

As discussed above, the valve body106can be controlled to allow the delivery of pressurized fluid from the pressure source104to one or more (or none) of the flexible members130of the peristaltic pump102. For example, the valve body106can be controlled to deliver a pressurized fluid to the first, second, and/or third occluders112a,112b, and/or112cin a predetermined sequence. The predetermined sequence can cause the peristaltic pump102to advance a small, precise volume of liquid along the fluid line110, such as for dispensing out of the fluid line110. The following provides an example pumping sequence that includes the control of pressurized fluid delivery to the occluders112of the peristaltic pump for advancing a small, precise volume of liquid along the fluid line110. Other sequences of pressurized fluid delivery to the occluders112are within the scope of this disclosure.

FIG. 5illustrates the peristaltic pump102in an example first position of the pumping sequence where pressurized fluid from the pressure source104is provided (via the valve body106) to the inner chamber135of the flexible member130of the first occluder112a, thereby allowing the flexible member to form an extended configuration. As shown inFIG. 5, in the extended configuration the flexible member130can extend approximately perpendicular to the fluid passageway108. This can allow the flexible member130to pinch the flexible fluid line110extending along the fluid passageway108. For example, the occluding end of the flexible member can apply a force against the fluid line to cause the fluid line110to pinch between the occluding end132and a side of the fluid passageway108. As such, the flexible member130of the first occluder112acan prevent fluid flow at the pinched location thus preventing free-flow along the fluid line.

FIG. 6illustrates the peristaltic pump102in an example second position of the pumping sequence where pressurized fluid from the pressure source104is provided (via the valve body106) to the inner chambers135of the flexible members130of the first and second occluders112a,112b, thereby allowing such flexible members130to form extended configurations. As shown inFIG. 6, the second occluder112bincludes an occluding end132of the flexible member130that is angled relative to a longitudinal axis of the body of the occluder and/or the fluid line110. The angled occluding end can assist with advancing fluid in the fluid line. For example, as shown inFIG. 6, the angled occluding end can be angled such that as the associated flexible member forms the extended configuration, the fluid line can experience a gradual closing of the inner lumen along the length of the occluding end, with the gradual closing occurring in the direction of fluid flow. As such, as the second occluder pinches the fluid line, fluid positioned along the fluid line adjacent the second occluder can be caused to advance past at least the second occluder in the direction of fluid flow.

In some embodiments, the occluding ends132of the flexible members130of the first and third occluders112a,112ccan be parallel relative to the longitudinal axis of the fluid passageway108and/or perpendicular to the longitudinal axis of the body of the associated occluder body. Other shapes and profiles of the occluding end132of the flexible member130are within the scope of this disclosure.

FIG. 7illustrates the peristaltic pump102in an example third position of the pumping sequence where pressurized fluid from the pressure source is provided (via the valve body106) to the inner chambers135of the flexible members130of the second and third occluders112b,112c, thereby allowing the flexible members to form extended configurations. For example, in the third position of the pumping sequence, fluid can be prevented from advancing past the second and third occluders thereby preventing free-flow of fluid along the fluid line.

FIG. 8illustrates the peristaltic pump102in an example fourth position of the pumping sequence where pressurized fluid from the pressure source is provided (via the valve body106) to the inner chamber135of the flexible member130of the third occluder112c, thereby allowing the flexible member of the third occluder to form (or maintain in) the extended configuration. For example, in the fourth position of the pumping sequence, fluid can be allowed to advance up to but not past the flexible member130of the third occluder112c. The pumping sequence can then be started again to thereby advance fluid positioned along the fluid line adjacent the second occluder112b, as described above.