Method and apparatus for drug infusion

• US 6,190,359 B1
• Filed: 10/11/1999
• Issued: 02/20/2001
• Est. Priority Date: 04/30/1996
• Status: Expired due to Fees

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Heruth, Kenneth T.
• Primary Examiner(s): Kennedy, Sharon
• Assistant Examiner(s): Lam, Ann Y.
• Application Number:
  US09/415,809
• Time in Patent Office: 498 Days
• Field of Search: 604/131, 604/94.01, 604/95.01, 604/95.02, 604/95.03, 604/48, 604/40, 604/133, 604/141
• US Class Current: 604/131
• CPC Class Codes: A61M 2005/14506 mechanically driven, e.g. spring or clockwork
• CPC Class Codes: A61M 2005/14513 with secondary fluid driving or regulating the infusion
• CPC Class Codes: A61M 5/14276 specially adapted for implantation

Abstract

The present disclosure describes a system wherein a drug or other fluid to be delivered to a specific desired location within the body is stored in a reservoir that is directly displaced by a force to infuse the drug from the device into the patient. Several specific methods are used to displace the reservoir, including, generally, hydraulic displacement, mechanical screw-type displacement, and spring force displacement of the fluid reservoir.

Claims

1. A periodically refillable drug infusion device to be implanted within a living body, comprising:

a drug fluid reservoir for receiving a supply of drug fluid;

a spring force displacer for selectively controlling the egress of drug fluid from said drug fluid reservoir for delivery into said living body, said displacer including a bellow-like expandable chamber annealed so that the chamber in its natural state assumes a collapsed position, and in an expanded state the chamber tends toward its natural collapsed position under its own action; and

a motor assembly, including a motor operatively coupled to a flywheel about which a first end of a cable having first and second ends is wrapped, said second end of said cable being attached to said bellows-like expandable chamber and wherein said motor assembly adjusts the position of the bellows-like expandable chamber as it relaxes from a first expanded state to a second more collapsed state to control the displacement of the fluid reservoir.

2. A periodically refillable drug infusion device to be implanted within a living body, comprising:

a drug fluid reservoir for receiving a supply of drug fluid;

a drug fluid reservoir displacer for selectively controlling the ingress of drug fluid into said drug fluid reservoir and selectively controlling the egress of drug fluid out of said drug fluid reservoir for delivery into said living body, said drug fluid reservoir displacer including a spring force displacer, the spring force displacer including a bellows-like expandable chamber annealed so that the chamber in its natural state assumes a collapsed position, and in an expanded state the chamber tends toward its natural collapsed Position under its own action; and

a motor assembly, including a motor operatively coupled to a flywheel about which a first end of a cable having first and second ends is wrapped, said second end of said cable being attached to said bellows-like expandable chamber; and

wherein said motor assembly adjusts the position of the bellows-like expandable chamber from a first contracted state to a second more expanded state to displace the fluid reservoir.

3. A periodically refillable drug infusion device to be implanted within a living body, comprising:

a drug fluid reservoir for receiving a supply of drug fluid;

said drug fluid reservoir defining a base, said drug fluid reservoir including an access port through which said drug fluid is introduced into said reservoir and an exit port through which said drug fluids delivered from said reservoir to said living body;

a motor operatively coupled to a rotatable member; and

a connector having first and second ends, said first end being attached to said rotatable member, said second end being attached to said base,

said member being rotatable by said motor in a first direction wherein said cable wraps about the rotatable member to displace said base from a natural state to increase the volume of said reservoir and draw the drug fluid into said reservoir through the access port;

said member being rotatable in a second direction by said motor to allow said base to return to the natural state to decrease the volume of said reservoir and meter the drug fluid through the exit port from the reservoir.

4. The apparatus of claim 3, wherein the drug fluid reservoir defines collapsible walls extending from the base, wherein said walls are in a collapsed position when said base is in said natural state.

5. The apparatus of claim 4, wherein said collapsible walls comprise bellows, said bellows being annealed such that in said natural state, said bellows are collapsed.

6. The apparatus of claim 3, wherein said rotatable member comprises a flywheel.

7. The apparatus of claim 3, wherein said rotatable member comprises a pully.