Apparatus and method for micro-volume infusion

• US 20020062105A1
• Filed: 09/25/2001
• Published: 05/23/2002
• Est. Priority Date: 09/22/2000
• Status: Abandoned Application

• Current Assignee: David N. Jones, Howard M.C. Tanner, Royce Herbst, Stephen R. Topaz
• Original Assignee: David N. Jones, Howard M.C. Tanner, Royce Herbst, Stephen R. Topaz
• Inventors: Topaz, Stephen R., Jones, David N., Herbst, Royce, Tanner, Howard M. C.
• Application Number:
  US09/963,021
• Publication Number:
  US 20020062105A1
• Time in Patent Office: Days
• US Class Current: 604/131
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 5/14232 Roller pumps
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body

Abstract

An apparatus and method for volumetric micro-liter infusion of therapeutic liquids. This portable pump system remains unobtrusive and less restrictive of patient ambulation and orientation. The present invention includes expendables, the disposability of which facilitates safe reuse of more expensive portions and is sufficiently simple for use in a home care environment. It may be designed to incorporate real-time, interactive or remote monitoring and regulation and visual or audible indication of system pressures, chemical balances and other important variables.

Claims

1. A portable peristaltic pump system for volumetric micro-liter infusion of therapeutic fluid, including:

a motor;

a drive train;

a roller housing associated with and driven by said motor through said drive train, said roller housing comprising;

a plurality of rollers, each roller structured and arranged to rotate around a respective roller axis; and

a housing axis around which said roller housing is mounted to revolve on a plane;

wherein said plane is substantially parallel with respect to each said respective roller axis;

a disposable cartridge interface, comprising a collapsible fluid conduit including an upstream end and a downstream end; and

a drive plate structured and arranged to abut a first side of said fluid conduit as each respective roller presses against a second side of said fluid conduit while the roller housing revolves;

whereby fluid may be transferred from a source into said fluid conduit through said upstream end and then out said downstream end to a destination.

2. The pump system of claim 1, further comprising a gear assembly associated with said drive train and capable of reducing the rpm'"'"'s of said motor.

3. The pump system of claim 2, wherein said motor rotates at approximately 5,500 rpm and said gear assembly is structured and arranged to reduce the rpm'"'"'s of said motor to about 20 rpm'"'"'s.

4. A portable peristaltic pump system for volumetric micro-liter infusion of

therapeutic liquid, including:

a motor which rotates at approximately 5,500 rpm;

a drive train, including a gear assembly capable of reducing the rpm'"'"'s of said motor to about 20 rpm'"'"'s;

a roller housing associated with and driven by said motor through said drive train, said roller housing comprising;

a plurality of rollers, each roller structured and arranged to rotate around a respective roller axis; and

a housing axis around which said roller housing can revolve on a plane;

wherein each respective roller axis is not perpendicular with respect to said plane;

a disposable cartridge interface, comprising a collapsible fluid conduit including an upstream end and a downstream end; and

a drive plate structured and arranged to abut a first side of said fluid conduit as each respective roller presses against a second side of said fluid conduit while said roller housing revolves;

whereby fluid may be transferred from a source into said fluid conduit through said upstream end and then out said downstream end to a destination.

5. The pump system of claim 4, wherein said collapsible fluid conduit is integrally formed as a part of a flexible cassette path with a periphery.

6. The pump system of claim 5, wherein said disposable cartridge interface further comprises a rigid or semi-rigid member circumscribing a majority of said periphery of said flexible cassette path.

7. The pump system of claim 5, wherein said flexible cassette path is formed of a polyurethane material.

8. The pump system of claim 6, wherein said rigid or semi-rigid member is formed of a polystyrene material.

9. A portable peristaltic pump system for volumetric micro-liter infusion of

therapeutic liquid, including:

a motor which rotates at approximately 5,500 rpm;

a drive train, including a gear assembly capable of reducing the rpm'"'"'s of said motor to about 20 rpm'"'"'s;

a roller housing associated with and driven by said motor through said drive train, said roller housing comprising;

a plurality of rollers, the exterior circumference of each said roller including a pinch surface and each said roller structured and arranged to rotate around a respective roller axis; and

a housing axis around which said roller housing can revolve on a plane;

wherein said pinch surface of each respective roller axis is along at least one position of rotation substantially parallel with respect to said plane;

a disposable cartridge interface, comprising a collapsible fluid conduit including an upstream end and a downstream end; and

a drive plate structured and arranged to abut a first side of said fluid conduit as said pinch surface of each respective roller presses against a second side of said fluid conduit while said roller housing revolves;

whereby fluid may be transferred from a source into said fluid conduit through said upstream end and then out said downstream end to a destination.

10. A method of manufacturing a mask work embodying an integral cavity configuration, comprising the steps of:

providing a mold plate assembly comprising a first face in which a desired cavity configuration with a periphery is formed, a second face for abutting said first face and at least one access point whereby negative or positive pressure from a source external to said mold plate may be applied to said cavity configuration;

providing a sheet of flexible polymer flat stock with a first exposure and a second exposure facing a direction opposite said first exposure;

placing at least a first portion of said flat stock between said first side and said second side of said mold plate assembly with said first exposure abutting said first face and anchoring said first side and said second side together with said first portion of flat stock remaining indwelling between said first side and said second side;

associating said mold plate assembly including said indwelling first portion of flat stock with said external pressure source;

heating said mold plate assembly and said indwelling first portion of flat stock to a degree sufficient to surmount a first memory characteristic of said flat stock;

applying selectively negative or positive pressure to said cavity configuration in sufficient degree to displace a part of said flat stock specifically into said cavity configuration;

cooling said flat stock to a degree sufficient to establish a second memory characteristic of said part of said flat stock displaced into and in conformity with said cavity configuration, such that said first exposure of said first portion of said flat stock is formed to include a convex configuration corresponding to said cavity configuration and said second exposure is formed to include a concave configuration corresponding to said cavity configuration;

removing said first portion of said flat stock from between said mold plate assembly and folding a second portion of said flat stock against said first portion such that said second exposure of said first portion is opposite to and lays against said second exposure of said second portion; and

bonding said first portion and said second portion together in close proximity to said periphery of said cavity configuration.

11. The method of claim 10, wherein said bonding is accomplished by a dielectric weld.

12. The method of claim 11, wherein said dielectric weld forms a continuous seal along said entire periphery of said cavity configuration.

13. The method of claim 12, wherein said cavity configuration defines a fluid conduit for use in a cassette path of a disposable cartridge interface of a peristaltic pump.

14. The method of claim 13, wherein said cavity configuration further comprises at least one compartment structured and arranged to accommodate a fluid metering device.

15. The method of claim 13, wherein said cavity configuration further comprises at least one compartment structured and arranged to accommodate a pressure sensor.

16. The method of claim 15, wherein said pressure sensor is structured and arranged to communicate interactively with said pump in response and relative to information provided by said pressure sensor and any preprogramming of said pump.

17. The method of claim 10, wherein said bonding is accomplished with a dielectric weld and forms a continuous seal along said entire periphery of said cavity configuration to define a fluid flow path, said flow path including an upstream fluid opening and a downstream fluid opening, and wherein said bonding further comprises bonding said first portion and said second portion together at or near an outer edge of said flat stock to define a bag portion space between said first exposure and second exposure that is in communication with said upstream fluid opening but sealed against fluid flow in any other direction.

20. The pump system of claim 19, whereby fluid flow may be further reduced to preselected micro-liter flow rates substantially lower than rates of flow achievable by said pump mechanism alone.

21. The pump system of claim 19, wherein a pressure sensor is associated with said downstream conduit upstream from said fluid restrictor stage, whereby pressure characteristics of said fluid in said downstream conduit upstream from said fluid restrictor stage may be ascertained to a more subtle degree thereby enabling inference of pressure characteristics of said fluid in said downstream conduit downstream from said fluid restrictor stage, said pressure sensor being in communication with said governing means.

22. The pump system of claim 21, wherein said pressure characteristics may include:

pressure status;

pressure change;

rate of pressure change;

or

any or all of the foregoing;

whereby said pressure sensor may communicate pressure characteristics to said governing means as a basis for said governing means to govern and coordinate actuation of said plurality of valves for achievement of optimal pump system performance in accordance with predetermined specifications.

24. The pump system of claim 23, whereby said pump governing means and said actuation governing means are coordinated based upon said information signal to achieve either dynamic valving or dynamic metering or both dynamic valving and dynamic metering of fluid flow within said downstream conduit.

25. The pump system of claim 24, wherein said pressure transducer is a strain gauge capable of sensing mechanical movement by means of changes in an electrical signal from a micro circuit.

27. Said pump system of claim 26, wherein operation of said at least one valve to open said at least one interface channel to fluid flow may increase volume throughput capacity up to 1 liter per hour.

28. Said pump system of claim 26, wherein operation of all of said at least one valve to close all but one of said plurality of interface channels to fluid flow may decrease volume throughput capacity to about 0.05 ml per hour.

30. Said pump system of claim 29, wherein said fluid flow may be in communication with a pressure sensor or fluid metering means or both a pressure sensor and fluid metering means to achieve greater consistency and definition in dynamic fluid flow.

18. A portable peristaltic pump system for volumetric micro-liter infusion of

therapeutic fluid, including:

a motor which rotates at approximately 5,500 rpm;

a drive train, including a gear assembly capable of reducing the rpm'"'"'s of said motor to about 20 rpm'"'"'s;

a roller housing associated with and driven by said motor through said drive train, said roller housing comprising;

a plurality of rollers, said exterior circumference of each roller including a pinch surface and each roller structured and arranged to rotate around a respective roller axis; and

a housing axis around which said roller housing can revolve on a plane;

wherein said pinch surface of each respective roller axis is along at least one position of rotation substantially not perpendicular with respect to said plane;

a disposable cartridge interface, comprising;

a cassette path formed of polyurethane or other flexible medical grade flat stock wherein is formed a cavity configuration comprising a collapsible fluid conduit between an upstream inlet a downstream outlet, said conduit compressible by said pinch surface of each roller as each roller rolls across said conduit; and

a drive plate structured and arranged to abut a first side of said fluid conduit as said pinch surface of each respective roller presses against a second side of said fluid conduit while said roller housing revolves;

whereby fluid may be transferred from a source into said fluid conduit through said upstream end and then out said downstream end to a destination.

19. A portable pump system for volumetric micro-liter infusion of therapeutic fluid, including:

a pump mechanism;

a fluid conduit comprising an upstream conduit, a downstream conduit and an interface conduit associated with said pump mechanism for pumping fluid; and

a fluid metering system in fluid communication with said downstream conduit and comprising;

a plurality of valves;

a means of governing actuation of said plurality of valves in accordance with an information signal; and

a fluid restrictor stage including a plurality of possible fluid flow paths any one or combination or all of which may be selectively accessed or bypassed in accordance with actuation of any or all of said plurality of said valves subject to said actuation governing means.

23. A portable pump system for volumetric micro-liter infusion of therapeutic fluid, including:

a pump mechanism;

a fluid conduit comprising an upstream conduit, a downstream conduit and an interface conduit associated with said pump mechanism for pumping fluid; and

a signal processing feedback loop associated with said downstream conduit and comprising;

a means of governing the rpm rate of said pump mechanism in accordance with an information signal; and

a pressure transducer in communication with said pump governing means,

capable of ascertaining pressure characteristics of said fluid within said downstream conduit, and

capable of supplying to said pump governing means said information signal pertaining to ascertained pressure characteristics.

26. A portable peristaltic pump system for volumetric micro-liter infusion of therapeutic liquid, including:

a motor which rotates at approximately 5,500 rpm;

a drive train, including a gear assembly capable of reducing the rpm'"'"'s of said motor to about 20 rpm'"'"'s;

a roller housing associated with and driven by said motor through said drive train, said roller housing comprising;

a plurality of rollers, said exterior circumference of each roller including a pinch surface and each roller structured and arranged to rotate around a respective roller axis; and

a housing axis around which said roller housing can revolve on a plane;

wherein said pinch surface of each respective roller axis is along at least one position of rotation substantially parallel with respect to said plane;

a disposable cartridge interface, comprising;

a collapsible fluid conduit, including an upstream conduit, a peristaltic interface in fluid communication with said upstream conduit and a downstream conduit in fluid communication with said peristaltic interface;

said peristaltic interface comprising a plurality of interface channels each including;

an upstream end,

at least one valve located near said upstream end of at least one of said plurality of interface channels, and

means whereby said at least one valve may be operated to open and thereby admit fluid from said upstream conduit through said upstream end of at least one interface channel or to close and thereby prevent fluid from said upstream conduit through said upstream end of at least one interface channel, thereby to respectively increase or decrease fluid throughput through said plurality of interface channels;

a drive plate structured and arranged to abut a first side of said fluid conduit as said pinch surface of each respective roller presses against a second side of said fluid conduit along a substantial portion of said peristaltic interface housed between said first side and second side while said roller housing revolves;

whereby fluid may be transferred from a source into said fluid conduit through said upstream end and then out said downstream end to a destination.

29. A portable acoustic streaming pump system for volumetric micro-liter infusion of therapeutic fluid, including:

a fluid conduit comprising an upstream conduit, a downstream conduit and an interface conduit;

a fluid chamber in communication with said fluid conduit; and

a piezoelectric material wafer associated with said fluid chamber and in communication with a source of electric current;

whereby electric current may be introduced to said piezoelectric material to cause a deflection of said wafer repeatedly resulting in a fluid flow within said conduit.