Controlled release osmotic pump

• US 5,672,167 A
• Filed: 04/15/1994
• Issued: 09/30/1997
• Est. Priority Date: 05/21/1990
• Status: Expired due to Fees

• Current Assignee: Recordati SPA (Fimei Finanziaria Industriale Mobiliare ED Immobiliare SPA)
• Original Assignee: Recordati SPA (Fimei Finanziaria Industriale Mobiliare ED Immobiliare SPA)
• Inventors: Low, Thomas P., Faste, Rolf A., Horres, C. Russell Jr., Athayde, Amulya L.
• Primary Examiner(s): ELGART, VANITHA M
• Assistant Examiner(s): Alexander, V.
• Application Number:
  US08/227,968
• Time in Patent Office: 1,264 Days
• Field of Search: 604/892.1, 604/131, 604/132, 604/141, 604/148, 604/151, 604/86, 604/87, 604/410, 128/DIG. 12, 424/422, 424/424
• US Class Current: 604/892.1
• CPC Class Codes: A61M 2005/14513 with secondary fluid driving or regulating the infusion
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/1483 using flexible bags externally pressurised by fluid pressure
• CPC Class Codes: Y10S 977/956 Of mechanical property

Abstract

A portable osmotic pump, having two pouches (4,3) in pressure-transmitting relationship, the first (4) containing a pumped fluid, such as infusate (5), and the second (3), a driving fluid (36). The driving fluid is created and pressurized by activation of an osmotic pump, and the rate of infusion is controlled by a semipermeable membrane (10). Activation can be by rupturing a seal (11) or by opening a closed tube (58) to permit permeant (2) to contact the semipermeable membrane. Pulses of the pumped fluid can be achieved by delivery pulses of the permeant to the second pouch. The pouches can be designed to resist collapse of the first pouch by external forces on the pumped liquid, such as gravity, movement of the first pouch and negative pressures applied to the pumped liquid. The infusate pouch is manufactured separately and can be stored apart from the rest of the system.

Claims

1. A pump comprising:

a. a first pouch containing a liquid to be pumped and having an outlet;

b. a second pouch in pressure transmitting relationship to said first pouch;

c. an integral power source comprising;

a pressure generating means for generating pressure in said second pouch, comprised of an osmagent and a liquid permeant, wherein a driving fluid is produced when the liquid permeant contacts the osmagent;

d. a housing containing said first and second pouches said housing being in restraining relationship to the aforesaid first and second pouch;

e. an activating means for initiating the action of said pressure generating means comprising;

a flexible tube fluidly coupling the liquid permeant which is to contact the osmagent with a semipermeable membrane when the flexible tube is in an open condition; and

means for selectively retaining the tube in a closed condition thereby fluidly isolating the liquid permeant from the semipermeable membrane.

2. The pump according to claim 1 where the first pouch holds:

a. a drug in dry form;

b. a pharmaceutically acceptable solvent for said drug; and

c. a breakable seal in separating relationship to said drug and solvent.

3. The pump of claim 1 wherein the selectively retaining means includes clamp means for maintaining the tube in a z-shaped collapsed condition.

4. The pump of claim 1 wherein the flexible tube includes an inner surface and the selectively retaining means includes:

a. an adhesive covering at least a section of the inner surface to permit said section to be collapsed and sealed by the adhesive; and

b. means for pressurizing the liquid permeant so to apply a separating force to said section of the inner surface so to place the tube in the open condition.

5. The pump of claim 1 wherein the selectively retaining means includes means for twisting the tube to place the tube in the closed condition.

6. The pump of claim 1, where said activating means further comprises means for breaking a barrier separating the permeant from contact with the semipermeable membrane.

7. The pump of claim 6, where:

a. said activating means is a plunger breaking said barrier; and

b. said barrier is a seal separating the permeant from contact with the semipermeable membrane.

8. The pump of claim 7 further comprising a container external to said housing for said permeant, said tube being connected between said container and said second pouch, and said barrier and plunger are incorporated in said container.

9. The pump of claim 1 further comprising a container external to said housing for said permeant, said tube being connected between said container and said second pouch.

10. The pump of claim 1 where said first pouch is loaded with the liquid to be pumped separately from the rest of the pump, and is then insertable into said housing.

11. The pump of claim 1 where the liquid to be pumped contained in the first pouch is chosen from a group of drugs including heparin, insulin, fluororacil, cisplatin, gancyclovir and adriamycin.

12. The pump of claim 1 wherein:

the housing also contains said power source.

13. The pump according to claim 1, further comprising a semipermeable membrane in communication with said second pouch to control the rate of flow of the liquid permeant to said second pouch for regulating the volume change of the driving fluid in said second pouch.

14. A pump comprising:

a. a first pouch containing a liquid to be pumped and having an outlet;

b. a second pouch in pressure transmitting relationship to said first pouch;

c. an integral power source comprising;

a pressure generating means for generating pressure in said second pouch, comprised of an osmagent and a liquid permeant, wherein a driving fluid is produced when the liquid permeant contacts the osmagent;

an activating means for initiating the action of said pressure generating means;

a rate-controlling means for regulating the volume change of said first pouch comprising a semipermeable membrane;

d. a housing containing said first and second pouches and in restraining relationship to the aforesaid first and second pouch and

e. means for temporarily increasing the flow of liquid permeant to the second pouch to react with the osmagent in the second pouch to produce a temporary pulse of driving fluid in the second pouch to transmit pressure to the first pouch so as to deliver a temporarily increased flow of the pumped liquid through the outlet of the first pouch.

15. The pump of claim 14 wherein the osmagent is in the second pouch and the temporarily increasing means includes means for delivering a pulse of the liquid permeant to the second pouch so to deliver a pulse of the pumped liquid through the outlet.

16. The pump of claim 15 wherein the pulse delivering means is a user-actuated one-way pulse pump.

17. The pump of claim 14 wherein the temporarily increasing means includes means for limiting the frequency of actuation thereof.

18. A pump comprising:

a. a first pouch containing a liquid to be pumped and having an outlet;

b. a second pouch in pressure transmitting relationship to said first pouch;

c. an integral power source comprising;

a pressure generating means for generating pressure in said second pouch, comprised of an osmagent and a liquid permeant, wherein a driving fluid is produced when the liquid permeant contacts the osmagent;

an activating means for initiating the action of said pressure generating means;

a rate-controlling means comprising a semi-permeable membrane for regulating the volume change of said first pouch; and

d. a housing containing said first and second pouches and in restraining relationship to the aforesaid first and second pouch; and

e. said first and second pouches having means for forcing engagement between the first and second pouches for assisting the first pouch to resist collapsing when subjected to at least one of the following forces selected from the group consisting of;

a negative pressure applied to the outlet, a gravity force applied to the first pouch and a force due to movement of the first pouch.

19. The pump of claim 18 wherein the means for forcing engagement includes means for mechanically connecting the first pouch to the second pouch between the first and second pouches.

20. The pump of claim 18 wherein the means for forcing engagement comprises said first pouch being of semi-rigid material and formed in an accordion-like shape.

21. The pump of claim 20 wherein the first pouch has a portion adjacent and affixed to the second pouch.

22. A pump comprising:

a. a first pouch having an outlet and containing a liquid to be pumped through said outlet;

b. a second pouch in pressure-transmitting relationship to said first pouch;

c. an integral power source comprising;

a pressure generating means for generating pressure in said second pouch, comprised of an osmagent and a liquid permeant, wherein a driving fluid is produced when the liquid permeant contacts osmagent;

an activating means for initiating the action of said pressure generating means;

a rate-controlling means for regulating the volume change of said first pouch, comprising a semipermeable membrane;

d. means for temporarily increasing the flow of liquid permeant to the second pouch to react with the osmagent in the second pouch to produce a temporary pulse of driving fluid in the second pouch to transmit pressure to the first pouch to deliver a temporarily increased flow of the liquid pumped through said first pouch outlet; and

e. means for applying a force to the first pouch for assisting the first pouch to resist collapsing when subjected to at least one of the following forces selected from the group consisting of;

a negative pressure applied to the outlet, a gravity force applied to the first pouch and a force due to movement of the first pouch.

23. A method for pumping a liquid to a receiver, comprising connecting said receiver to a pump, said pump comprising:

a. a first pouch having an outlet and containing the liquid to be pumped;

b. a second pouch in pressure-transmitting relationship to said first pouch;

c. an integral power source comprising;

a pressure generating means for generating pressure in said second pouch, comprised of an osmagent and a liquid permeant, wherein a driving fluid is produced when the liquid permeant contacts osmagent;

an activating means for initiating the action of said pressure generating means;

a rate-controlling means for regulating the volume change of said first pouch, comprising a semipermeable membrane;

d. a housing containing said first and second pouches and in restraining relationship to said first and second pouches; and

e. a pump for delivering a temporary pulse of the liquid permeant to the second pouch to react with the osmagent to produce a temporary pulse of the driving fluid in the second pouch so to deliver a pulse of the liquid pumped through the first pouch outlet.

24. The method of claim 23 wherein the connecting step is carried out with a housing containing the first pouch, second pouch and power source.

25. The method of claim 23 further comprising the step of activating the pump by opening a flexible tube to fluidly couple the liquid permeant and the semipermeable membrane.