Constant flow medication infusion pump

• US 6,280,416 B1
• Filed: 02/19/1999
• Issued: 08/28/2001
• Est. Priority Date: 02/19/1999
• Status: Expired due to Term

• Current Assignee: Minimed, Inc. (Medtronic Plc)
• Original Assignee: Minimed, Inc. (Medtronic Plc)
• Inventors: Van Antwerp, William P., Lord, Peter C., McConnell, Susan M.
• Primary Examiner(s): Nguyen, Anhtuant T.
• Assistant Examiner(s): Thompson, Michael M.
• Application Number:
  US09/253,382
• Time in Patent Office: 921 Days
• Field of Search: 604/891.1, 604/890.1, 604/132, 604/140, 604/141, 604/142, 604/93, 604/93.01, 604/131, 128/DIG.12
• US Class Current: 604/141
• CPC Class Codes: A61M 5/141 with capillaries for restricting fluid flow
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/1483 using flexible bags externally pressurised by fluid pressure
• CPC Class Codes: A61M 5/155 pressurised by gas introduced into the reservoir
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

A medication infusion pump includes a housing, a medication chamber defined within the housing, a medication delivery device in fluid communication with the medication chamber, a propellant chamber defined within the housing and adapted to apply a predetermined positive pressure to a medication in the medication chamber, and a non-ozone depleting, non-toxic propellant within the propellant chamber. The propellant preferably has a vapor pressure between about 11 psig and about 50 psig at 37° C.

Claims

1. A medication infusion pump comprising

a) a housing,

b) a medication chamber defined within said housing,

c) a medication delivery device in fluid communication with said medication chamber,

d) a propellant chamber defined within said housing and adapted to apply predetermined positive pressure to a medication within said medication chamber, and

e) a non-ozone depleting, non-toxic propellant within said propellant chamber.

2. The medication infusion pump of claim 1 wherein said propellant has a vapor pressure between about 11 psig and about 50 psig at 37°

C.

3. The medication infusion pump of claim 2 wherein said propellant has a vapor pressure between about 20 psig and about 24 psig at 37°

C.

4. The medication infusion pump of claim 1 wherein said propellant is selected from the group consisting of HFA-134a, HCFC-141b and neopentane.

5. The medication infusion pump of claim 1 wherein said propellant is selected from the group consisting of HFA-134a and HCFC-141b.

6. The medication infusion pump of claim 1 comprising a mixture of at least two propellants.

7. The medication infusion pump of claim 1 comprising at least one propellant in admixture with at least one diluent gas.

8. The medication infusion pump of claim 7 wherein said diluent is selected from the group consisting of O₂, N₂, CO₂, Ar, Xe and He.

9. A medication infusion pump that dispenses a medication at a substantially constant flowrate by application to said medication of a predetermined positive pressure, wherein said pressure is exerted by a non-ozone depleting, non-toxic propellant having a vapor pressure between about 11 psig and about 50 psig at 37°

C.

10. The medication infusion pump of claim 9 wherein said propellant has a vapor pressure between about 20 psig and about 24 psig at 37°

C.

11. The medication infusion pump of claim 9 wherein said propellant is selected from the group consisting of HFA-134a, HCFC-141b and neopentane.

12. The medication infusion pump of claim 11 wherein said propellant is selected from the group consisting of HFA-134a and HCFC-141b.