VARIABLE INFUSION RATE CATHETER

• US 20020107471A1
• Filed: 02/02/2001
• Published: 08/08/2002
• Est. Priority Date: 02/02/2001
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Mattes, Michael F., Larson, Lary R., Heruth, Kenneth T., Thompson, David L.
• Granted Patent: US 6,749,581 B2
• Time in Patent Office: Days
• US Class Current: 604/21
• CPC Class Codes: A61M 2205/3507 with implanted devices, e.g. external control
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 5/16813 by controlling the degree of opening of the flow line
• CPC Class Codes: A61M 5/16881 Regulating valves on-off valves, e.g. clamps A61M39/28

Abstract

A medical device known as a catheter is configured with a variable infusion rate to deliver a therapeutic substance such as pharmaceutical compositions, genetic materials, and biologics to treat a variety of medical conditions such as pain, spastisity, cancer, and other diseases in humans and other animals. The variable infusion rate catheter provides clinician with increased flexibility, versatility, and many other improvements. The variable infusion rate catheter has a Micro Electro Mechanical System (MEMS) flow restriction with a variable infusion rate. The MEMS flow restriction is fluidly coupled to the catheter to receive therapeutic substance dispensed from a therapeutic substance delivery device and restrict the therapeutic substance flow to a desired infusion rate. Many embodiments of the variable infusion rate catheter and its methods of operation are possible.

Claims

1. A variable infusion rate catheter, comprising:

a catheter coupleable to a therapeutic substance delivery device, the catheter configured to deliver therapeutic substance to a delivery site in a body; and

,

a Micro Electro Mechanical System (MEMS) variable flow restriction fluidly coupled to the catheter, the MEMS variable flow restriction adjustable to vary the infusion rate from at least one catheter infusion opening.

2. The catheter as in claim 1 wherein the catheter is configured to be percutaneously inserted into a patient.

3. The catheter as in claim 1 wherein the catheter is configured to be programmed after implantation.

4. The variable infusion rate catheter as in claim 1 wherein the MEMS variable flow restriction further comprises,

a substrate having a therapeutic substance flow path with a therapeutic substance input, a flow restriction, and a therapeutic substance output;

a passive power source carried on the substrate, the passive power source capable of supplying power upon being energized by a radio frequency source;

electronics carried on the substrate and coupled to the passive power supply, the electronics generating a control signal;

an actuator carried on the substrate and coupled to the control electronics, the actuator moving in response to the control signal; and

,

a valve moveably coupled to the substrate to selectively engage the flow restriction, the valve operated by the actuator to selectively adjust the flow restriction to for an infusion rate.

5. The catheter as in claim 1 wherein the catheter has a proximal end and a distal end, the distal end having at least a first flow path and a second flow path, the first flow path and the second flow path each having a MEMS variable flow restriction capable of providing a first infusion rate and a second infusion rate.

6. A variable infusion rate catheter, comprising:

means for therapeutic substance delivery to deliver therapeutic substance to a delivery site; and

,

means for variable flow restriction fluidly coupled to the means for therapeutic substance delivery, the means for variable flow restriction including a Micro Electro Mechanical System (MEMS) variable flow restriction adjustable to vary the infusion rate from at least one catheter infusion opening.

7. A method for varying a catheter infusion rate, comprising:

positioning a MEMS variable flow control on a catheter;

energizing a passive power supply with a radio frequency signal;

powering electronics with the passive power supply;

receiving an information signal modulated on the radio frequency signal with the electronics;

generating a control signal that is responsive to the information signal with the electronics;

operating an actuator in response to the control signal; and

,

moving a valve with the actuator to adjust the flow restriction for an infusion rate.

9. A Micro Electo Mechanical System (MEMS) variable flow restriction for a catheter, comprising:

a substrate having a drug flow path with drug input, a flow restriction, and a drug output;

a passive power source carried on the substrate, the passive power source capable of supplying power upon being energized by a radio frequency source;

electronics carried on the substrate and coupled to the passive power supply, the electronics generating a control signal;

an actuator carried on the substrate and coupled to the electronics, the actuator moving in response to the control signal; and

,

a valve moveably coupled to the substrate to selectively engage the flow restriction, the valve operated by the actuator to selectively adjust the flow restriction to modulate the flow through the drug flow path.

8. The method as in claim 16, further comprising,

supplying the catheter with therapeutic substance;

and,

infusing therapeutic substance from the catheter at the programmed infusion rate.

10. The MEMS flow restrictor as in claim 9 wherein the control electronics include nonvolatile memory.

11. The MEMS flow restrictor as in claim 9 wherein the actuator is a D.C. motor coupled to the valve with a gear.

12. The MEMS flow restrictor as in claim 9 wherein the actuator is a heat motor coupled to the valve with a ratchet wheel.

13. The MEMS flow restrictor as in claim 9 wherein the actuator is a stepwise rotor coupled to the valve.

14. The MEMS flow restrictor as in claim 9 wherein the flow restriction is a continuous path.

15. The MEMS flow restrictor as in claim 9 wherein the flow restriction is a plurality of restriction outlets selectable by the valve.

16. A Micro Electo Mechanical System (MEMS) flow restriction for a catheter, comprising:

means for therapeutic substance flow having a therapeutic substance input, a flow restriction, and a therapeutic substance output;

means for power carried on the means for therapeutic substance flow, the means for power capable of supplying power upon being energized by a radio frequency source;

means for programming to store flow restriction program;

means for electronics control to receive the flow restriction program and generate a control signal;

means for actuation to create motion in response to the control signal; and

,

means for valving to adjust therapeutic substance flow through the flow restriction moveably coupled to the substrate to selectively engage the flow restriction, the shutter operated by the actuator to selectively adjust the flow restriction to modulate the flow through the drug flow path.