Reservoir pressure equalization systems and methods

• US 8,313,467 B2
• Filed: 12/27/2007
• Issued: 11/20/2012
• Est. Priority Date: 12/27/2007
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Chong, Colin A., Bikovsky, Rafael, Kavazov, Julian D., Lorenzen, Eric M., Sargent, Bradley J., Scherer, Andrew J., Bare, Rex O.
• Primary Examiner(s): Sirmons, Kevin C
• Assistant Examiner(s): Thomas, Jr., Bradley G
• Application Number:
  US11/965,578
• Publication Number:
  US 20090171324A1
• Time in Patent Office: 1,790 Days
• Field of Search: 604134-139, 604/67, 604/131, 604/148, 604/151, 604/218, 604/890.1, 604/200, 604/201, 604/187
• US Class Current: 604/148
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61M 2005/14264 with means for compensating influence from the environment
• CPC Class Codes: A61M 2005/14268 with a reusable and a disposable component
• CPC Class Codes: A61M 2039/267 having a sealing sleeve around a tubular or solid stem portion of the connector
• CPC Class Codes: A61M 2205/0216 Materials providing elastic properties, e.g. for facilitating deformation and avoid breaking
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/3337 Controlling, regulating pressure or flow by means of a valve by-passing a pump
• CPC Class Codes: A61M 2205/3592 using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/7527 liquophilic, hydrophilic
• CPC Class Codes: A61M 2205/7536 allowing gas passage, but preventing liquid passage, e.g. liquophobic, hydrophobic, water-repellent membranes
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/1452 pressurised by means of pistons
• CPC Class Codes: A61M 5/1456 with a replaceable reservoir comprising a piston rod to be moved into the reservoir, e.g. the piston rod is part of the removable reservoir
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: B65D 51/1633 whereby venting occurs by automatic opening of the closure, container or other element
• CPC Class Codes: F16K 17/02 opening on surplus pressure on one side; closing on insufficient pressure on one side check valves F16K15/00
• CPC Class Codes: Y10T 137/0318 Processes
• CPC Class Codes: Y10T 137/0396 Involving pressure control

Abstract

Various embodiments of the present invention are directed to equalizing pressure in a reservoir containing fluidic media, possibly due to imperfect installation of the reservoir or an external influence such as an altitude or a temperature change. In various embodiments, fluidic media may be expelled from the reservoir through a needle and contained in an interior volume of a pierceable member before the needle pierces the pierceable member to establish a flow path to a user. In other embodiments, fluidic media may be expelled through a port of the reservoir into a chamber. In further embodiments, fluidic media may be expelled through a channel in a plunger head and out a passage in the reservoir when the channel and passage are aligned. In other embodiments, fluidic media may be expelled through a valve, and the valve may be pierceable by a needle to establish a flow path to the user.

Claims

1. A system for equalizing pressure within a reservoir, the system comprising:

a first housing portion adapted to be carried by a user; and

a second housing portion configured to be selectively operatively engaged with and disengaged from the first housing portion;

a structure having a chamber, the structure supported by one of the first and second housing portions;

a needle connectable to the reservoir for allowing fluidic media contained in the reservoir to flow through the needle when the needle is connected to the reservoir, the needle having a piercing end; and

a pierceable member moveable, relative to the piercing end of the needle and the reservoir when the needle is connected to the reservoir, within the chamber of the structure in a direction along a longitudinal dimension of the needle, the pierceable member pierceable by the piercing end of the needle, the pierceable member having an interior volume extending along at least a portion of the longitudinal dimension of the needle before the pierceable member is pierced by the needle, the pierceable member having a first end for engaging the other of the first and second housing portions when the first housing portion and the second housing portion are operatively engaged, the pierceable member having a second end located on an opposite side of the pierceable member from the first end;

the structure configured to expel the fluidic media contained in the reservoir through the needle and out of the structure when the needle is connected to the reservoir and the pierceable member is pierced by the piercing end of the needle and as pressure within the reservoir is increased relative to pressure within the interior volume of the pierceable member;

wherein the pierceable member is arranged for movement in a first direction to a piercing position in which the piercing end of the needle pierces through the pierceable member, and in a second direction from the piercing position to a retracted position in which the piercing end of the needle is located inside the interior volume of the pierceable member.

2. The system according to claim 1, wherein fluidic media is expelled from the reservoir, through the needle before the pierceable member is pierced by the needle in a case where a pressure difference exists between the reservoir and the chamber.

3. The system according to claim 1, wherein fluidic media is expelled from the reservoir, through the needle before the pierceable member is pierced by the needle in a case where a pressure difference exists between the reservoir and the interior volume of the pierceable member.

4. The system according to claim 1, the piercing end of the needle is located at least substantially within the interior volume of the pierceable member before the pierceable member is pierced by the needle.

5. The system according to claim 1, wherein a cross-section of the pierceable member is U-shaped.

6. The system according to claim 1, the pierceable member positioned

to be pierced by the needle when the first housing portion and the second housing portion are operatively engaged;

the needle positioned to enter the other of the first and second housing portions from said one of the first and second housing portions when the first housing portion and the second housing portion are operatively engaged.

7. The system according to claim 1, a first portion of the chamber adjacent to the second end of the pierceable member, the first portion of the chamber for containing fluidic media in a case where fluidic media flows out of the interior volume of the pierceable member.

8. The system according to claim 7, the first portion of the chamber located between the pierceable member and the reservoir.

9. The system according to claim 7, a second portion of the chamber adjacent to an opposite side of the pierceable member from the first portion of the chamber, the second portion of the chamber for containing fluidic media in a case where fluidic media flows out of the first portion of the chamber.

10. The system according to claim 9, the pierceable member comprising:

a seal member for inhibiting fluidic media contained in the second portion of the chamber from flowing back into the first chamber.

11. The system according to claim 1,

the structure having an opening that communicates with the chamber, the opening for allowing fluidic media to be purged from the chamber in a case where fluidic media flows out of the interior volume of the pierceable member.

12. The system according to claim 1, the pierceable member comprising:

a membrane configured to expand to increase the interior volume of the pierceable member in a case where the interior volume of the pierceable member sufficiently fills with fluidic media.

13. The system according to claim 1, the system further comprising:

a bias member arranged to impart a bias force on the pierceable member, the bias force being in the second direction.

14. The system according to claim 13, wherein the bias member comprises a spring.

15. The system according to claim 1, the pierceable member having a resiliently flexible portion for providing a bias force on the pierceable member, the bias force being in the second direction.

16. The system according to claim 1,

the needle having a longitudinal dimension and a central axis along the longitudinal dimension;

the interior volume of the pierceable member curved concavely relative to the central axis of the needle.

17. The system according to claim 1, the system further comprising:

at least one seal member positioned between the structure and the pierceable member.

19. The system according to claim 1, the pierceable member arranged to surround a portion of the needle before the pierceable member is pierced by the needle.

20. The system according to claim 1,

wherein the needle is configured to allow fluidic media in the reservoir to flow through the needle in a case where the needle is connected to the reservoir.

21. The system according to claim 1, the pierceable member arranged such that the piercing end of the needle is disposed in the interior volume of the pierceable member to surround a portion of the needle before the pierceable member is pierced by the needle.

22. The system according to claim 1, wherein the pierceable member is arranged such that the fluidic media expelled from the reservoir, through the needle and out of the structure, does not contact the pierceable member and portions defining the interior volume of the pierceable member.

23. The system according to claim 1, wherein the needle is arranged such that the fluidic media that is expelled through the needle before the needle pierces the pierceable member and contained in the interior volume of the pierceable member is prevented from flowing out of the structure through the needle.

24. The system according to claim 1, the structure configured to equalize pressure between the reservoir and the interior volume of the pierceable member before the needle pierces the pierceable member by expelling the fluidic media contained in the reservoir through the needle into the interior volume of the pierceable member.

25. The system according to claim 1, wherein the needle is configured to be stationary and the pierceable member is configured to be movable so that movement of the pierceable member against the needle causes the needle to pierce the pierceable member.

26. The system according to claim 1, wherein at least some of the interior volume of the pierceable member is free of fluidic media as the fluidic media contained in the reservoir is expelled through the needle and out of the structure when the needle is connected to the reservoir and the pierceable member is pierced by the needle and as pressure within the reservoir is increased relative to pressure within the interior volume of the pierceable member.

27. The system according to claim 1, wherein the pierceable member is a septum having a unitary structure.

28. The system according to claim 1, wherein the pierceable member is arranged in the chamber of the structure before the needle pierces the pierceable member.

29. The system according to claim 28, wherein the pierceable member is arranged in the chamber of the structure at all times while the fluidic media is expelled out of the structure through the needle.

30. The system according to claim 1, the structure configured such that before the pierceable member is pierced by the needle, fluidic media contained in the reservoir is expelled through the needle and out the needle into the interior volume of the pierceable member, in a case where the needle is connected to the reservoir and the pressure within the reservoir is increased relative to pressure within the interior volume of the pierceable member;

and the structure configured such that after the pierceable member is pierced by the needle fluidic media contained in the reservoir is expelled out of the structure through the needle, in a case where the needle is connected to the reservoir and the pressure within the reservoir is increased relative to the pressure within the interior volume of the pierceable member.

31. The system according to claim 1,

wherein, when the needle is connected to the reservoir, the reservoir is configured to remain stationary as the pierceable member moves relative to the needle and the reservoir so that the pierceable member is pierced by the needle.

32. The system according to claim 1,

wherein the bias member is arranged such that bias force of the bias member moves the pierceable member in a direction opposite a direction in which the pierceable member was moved by a force to be pierced by the needle when the bias force is greater than the force.

33. The system according to claim 1,

wherein the pierceable member is arranged for movement in a first direction in which the pierceable member is pierced by the needle and a second direction opposite the first direction to withdraw the needle from outside the pierceable member into the interior volume of the pierceable member.

34. The system according to claim 1, the other of the first and second housing portions, relative to the one of the first and second housing portions supporting the structure, moveable against a surface of the pierceable member opposite a surface of the pierceable member facing the needle to cause the pierceable member to be pierced by the needle.

35. The system according to claim 1, the pierceable member having.

36. The system according to claim 1, wherein the pierceable member is biased toward the second direction by a bias force;

the structure is configured for selectively coupling and uncoupling with the other of the first and second housing portions;

the pierceable member has a surface arranged to be contacted by the base assembly and receive a force from the other of the first and second housing portions to cause the pierceable member to move against the bias force in the first direction relative to the needle and be pierced by the needle, when the structure is coupling with the other of the first and second housing portions.

37. The system according to claim 1, wherein the end of the needle is arranged within the structure before the pierceable member is pierced by the end of the needle.

38. The system according to claim 1, wherein the pierceable member is arranged completely within the structure before the pierceable by the end of the needle.

39. The system according to claim 1, the pierceable member having a pierceable portion for piercing by the end of the needle;

wherein the pierceable portion is arranged within the chamber of the structure before the pierceable member is pierced by the end of the needle.

40. The system according to claim 1, wherein the structure is configured to receive in the chamber at least a portion of the other of the first and second housing portions.

18. A method for equalizing a pressure within a reservoir, the method comprising:

providing a first housing portion adapted to be carried by a user; and

providing a second housing portion configured to be selectively operatively engaged with and disengaged from the first housing portion;

providing a structure having a chamber, the structure supported by one of the first and second housing portions;

locating a needle connectable to the reservoir for allowing fluidic media contained in the reservoir to flow through the needle when the needle is connected to the reservoir, the needle having a piercing end;

locating a pierceable member that is moveable, relative to the piercing end of the needle and the reservoir when the needle is connected to the reservoir, within the chamber of the structure in a direction along a longitudinal dimension of the needle, the pierceable member pierceable by the piercing end of the needle, the pierceable member having an interior volume extending along at least a portion of the longitudinal dimension of the needle before the pierceable member is pierced by the needle, the pierceable member having a first end for engaging the other of the first and second housing portions when the first housing portion and the second housing portion are operatively engaged, the pierceable member having a second end located on an opposite side of the pierceable member from the first end; and

configuring the structure to expel the fluidic media contained in the reservoir through the needle and out of the structure when the needle is connected to the reservoir and the pierceable member is pierced by the piercing end of the needle and as pressure within the reservoir is increased relative to pressure within the interior volume of the pierceable member supporting the pierceable member for movement within the chamber of the structure in a first direction to a piercing position in which the piercing end of the needle pierces through the pierceable member, and in a second direction from the piercing position to a retracted position in which the piercing end of the needle is located inside the interior volume of the pierceable member.