Constant rate fluid delivery device with selectable flow rate and titratable bolus button

• US 20020022798A1
• Filed: 08/17/2001
• Published: 02/21/2002
• Est. Priority Date: 08/18/2000
• Status: Active Grant

• Current Assignee: Becton, Dickinson & Co
• Original Assignee: Becton, Dickinson & Co
• Inventors: Powell, Kenneth G., Connelly, Robert I.
• Granted Patent: US 6,702,779 B2
• Time in Patent Office: Days
• US Class Current: 604/93.01
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/14586 pressurised by means of a flexible diaphragm
• CPC Class Codes: A61M 5/148 flexible, e.g. independent bagsA61M5/155 takes precedence
• CPC Class Codes: A61M 5/16881 Regulating valves on-off valves, e.g. clamps A61M39/28

Abstract

A wearable, self-contained drug infusion device is disclosed that is capable of achieving the precise flow rate control needed for dose-critical drugs such as insulin. In preferred embodiments of the device, at least two flow channels are utilized in conjunction with a series of valves for providing a user with selectable, constant flow rate control. The device can be made with small dimensions so that it can be worn by the user with a minimum of discomfort and inconvenience. In addition, the simple mechanical nature of the device provides the user with close control over the flow rate, which is required for safe and effective delivery of insulin and other drugs. Also, the absence of electronic components allows the device to be manufactured inexpensively. The device is provided with a first channel that is long and narrow, functioning as a flow restrictor. The first channel is preferably provided in a serpentine pattern. A second channel is also provided that has a larger cross section so that flow is not restricted. A series of valves are used to force the flow of fluid through a selectable portion of the serpentine portion of the first channel before entering the remainder of the second channel and flowing to the delivery cannula. In one embodiment of the device, a needle port is provided in fluid communication with the delivery cannula for delivering bolus injections. In another embodiment, a bolus button is provided for delivering bolus injections. A flow restrictor is preferably included in the bolus button to limit the rate at which the bolus button refills.

Claims

1. A device for delivering fluid at a constant selectable flow rate comprising:

a housing;

a reservoir in said housing for containing a supply of said fluid and for delivering said fluid under pressure;

first and second flow channels each having a proximal end and a distal end, said proximal ends being in fluid communication with said reservoir; and

a delivery cannula in fluid communication with said distal end of said first and second flow channels for delivering said fluid;

said first flow channel comprising a plurality of sections;

said second flow channel having a plurality of nodes, each node being in fluid communication with a corresponding section of said first flow channel, and capable of being closed, such that when a particular node is closed, fluid flowing from said reservoir toward said needle may not pass through the node but rather must pass through the corresponding section of said first flow channel.

2. A device as claimed in claim 1, wherein said second flow channel has a greater cross sectional area than said first flow channel.

3. A device as claimed in claim 1 wherein said first flow channel is formed in a serpentine pattern.

4. A device as claimed in claim 1 further having a resealable port in fluid communication with said delivery cannula for immediate delivery of additional fluid.

5. A device as claimed in claim 1, wherein said reservoir comprises at least one spring element for pressurizing said fluid contained in said reservoir.

6. A device as claimed in claim 5, wherein said spring element is a Belleville spring.

7. A device as claimed in claim 1 wherein said first and second flow channels are formed into said housing.

8. A device as claimed in claim 7 wherein at least one wall of said flow channels is formed by a flexible membrane.

9. A device as claimed in claim 1 wherein said nodes are defined by indentations in said housing, said device further having a flow rate selection device movably connected to said housing, said flexible membrane disposed between said housing and said flow rate selection device, said flow rate selection device further having a plurality of detents adapted to match said indentations such that said detents may be moved into alignment with any number of said indentations causing the corresponding nodes to be closed.

10. The device as claimed in claim 1 further comprising a self sealing needle port in fluid communication with said delivery cannula.

11. A method of injecting medication into a patient comprising the steps of:

providing a pressurized container of medicament in fluid communication with a proximal end of a first channel and a second channel, said first channel and said second channel each having a distal end in fluid communication with a cannula, said container having a plurality of nodes each in fluid communication with a section of said first channel and said second channel, said nodes being adapted such that when said nodes are in a closed position, fluid is not able to flow from said first channel to said second channel;

injecting said cannula into said patient;

closing a selected number of nodes;

delivering said medicament to said patient through said flow channels and said cannula at a flow rate determined by said selected number of nodes.

12. The method of claim 11, wherein said first channel has a substantially longer length and smaller cross section than said second channel.

13. The method of claim 11 wherein said providing step further comprises:

providing said pressurized container of medicament in a container comprising at least one flexible membrane sealed to a substantially flat surface.

14. The method of claim 13 further comprising:

pressurizing said medicament by flexing a spring against said container.

15. The method of claim 14 wherein said spring is a Belleville spring.

17. A device as claimed in claim 16, wherein said reservoir comprises at least one spring element for pressurizing said fluid contained in said reservoir.

18. A device as claimed in claim 17, wherein said spring element is a Belleville spring.

19. A device as claimed in claim 16, wherein said resealable port is adapted to accept a needle.

20. A device as claimed in claim 16, wherein said first flow channel is formed into said housing.

21. A device as claimed in claim 20, wherein at least one wall of said first flow channel is formed by a flexible membrane.

22. A device as claimed in claim 16,

wherein said first flow channel comprises a plurality of sections, and

wherein said device further comprises a second flow channel having a proximal end in fluid communication with said reservoir and a distal end in fluid communication with said delivery cannula;

said second flow channel having a greater cross sectional area than said first flow channel, and further having a plurality of nodes, each node being in fluid communication with a corresponding section of said first flow channel, and capable of being closed, such that when a particular node is closed, fluid flowing from said reservoir toward said needle may not pass through the node but rather must pass through the corresponding section of said first flow channel.

23. A device as claimed in claim 22, wherein said first flow channel is formed in a serpentine pattern.

25. A device as claimed in claim 24 wherein said second flow channel further comprises a check valve adapted to prevent the flow of fluid toward said reservoir.

26. A device as claimed in claim 24, wherein said second flow channel further comprises a flow restrictor adapted to restrict the flow of fluid through said second flow channel.

27. A device as claimed in claim 26, wherein said first flow channel comprises a plurality of sections, and wherein said device further comprises

a fourth flow channel having a proximal end in fluid communication with said reservoir and a distal end in fluid communication with said delivery cannula;

said fourth flow channel having a greater cross sectional area than said first flow channel, and further having a plurality of nodes, each node being in fluid communication with a corresponding section of said first flow channel, and capable of being closed, such that when a particular node is closed, fluid flowing from said reservoir toward said needle may not pass through the node but rather must pass through the corresponding section of said first flow channel.

28. A device as claimed in claim 27, wherein said first flow channel is formed in a serpentine pattern.

16. A device for delivering fluid at a constant flow rate comprising:

a housing;

a reservoir in said housing for containing a supply of said fluid and for delivering said fluid under pressure;

a first flow channel having a proximal end and a distal end, said proximal end being in fluid communication with said reservoir;

a delivery cannula in fluid communication with said distal end of said first flow channel for delivering said fluid; and

a resealable port in fluid communication with said delivery cannula for immediate delivery of additional fluid.

24. A device for delivering fluid at a constant flow rate comprising:

a housing;

a reservoir in said housing for containing a supply of said fluid and for delivering said fluid under pressure;

a first flow channels having a proximal end and a distal end, said proximal end being in fluid communication with said reservoir;

a delivery cannula in fluid communication with said distal end of said first flow channel for delivering said fluid;

a second flow channel having a proximal end in fluid communication with said reservoir, and a distal end in fluid communication with a bolus button; and

a third flow channel having a proximal end in fluid communication with said bolus button, a distal end in fluid communication with said delivery cannula, and a spring check valve adapted to prevent said fluid from flowing toward said bolus button and further adapted to allow said fluid to flow toward said delivery cannula only if a minimum pressure is exceeded;

wherein said bolus button is adapted to have a maximum volume, and is further adapted to be collapsed, causing fluid to flow through said spring check valve to said delivery cannula.