Septum monitoring system and method for an implantable therapeutic substance delivery device

• US 20070255235A1
• Filed: 04/28/2006
• Published: 11/01/2007
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Olsen, James, Rogers, Charles
• Granted Patent: US 8,491,547 B2
• Time in Patent Office: Days
• US Class Current: 604/288.10
• CPC Class Codes: A61M 2039/0244 having means for detecting an inserted needle
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2209/045 for filling, e.g. for filling reservoirs
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: A61M 5/14276 specially adapted for implantation

Abstract

A system for monitoring an implantable medical device. The system includes an implantable therapeutic substance delivery device for delivering a therapeutic substance, along with a temperature sensor and an indicator device. The delivery device includes a housing maintaining a reservoir for containing the therapeutic substance. Further, the delivery device includes a fill port assembly having a port chamber in fluid communication with the reservoir and including a septum fluidly sealing the chamber. The temperature sensor is associated with the fill port assembly. Finally, the indicator device is adapted to indicate presence of a needle within the port chamber based upon information from the temperature sensor.

Claims

1. A system for monitoring an implantable medical device, the system comprising:

an implantable liquid therapeutic substance delivery device for delivering a therapeutic substance to a delivery site within a patient, the device including;

a housing maintaining a reservoir for containing the therapeutic substance,

a fill port assembly defining a port chamber in fluid communication with the reservoir, the fill port assembly further including a septum fluidly sealing the port chamber relative to an exterior of the device;

a temperature sensor associated with the fill port assembly; and

an indicator device for indicating presence of a needle within the port chamber based upon information from the temperature sensor.

2. The system of claim 1, wherein the reservoir chamber is fluidly open to the reservoir, and further wherein the temperature sensor is positioned within the port chamber.

3. The system of claim 2, wherein the temperature sensor is positioned to sense a temperature of the port chamber.

4. The system of claim 2, wherein the temperature sensor is configured to sense a change in a temperature of the port chamber.

5. The system of claim 1, wherein the temperature sensor is adapted to sense presence of a liquid maintained at room temperature being infused into the port chamber.

6. The system of claim 1, wherein the indicator device is adapted to generate at least one of an audible and visual indication to a clinician of the presence of a needle within the port chamber.

7. The system of claim 6, wherein the indicator device includes a sound generator maintained by the housing.

8. The system of claim 6, further comprising:

an external programmer provided apart from the delivery device and adapted to wirelessly communicate with the delivery device;

wherein the indicator device includes a display screen associated with the external programmer.

9. The system of claim 6, wherein the indicator device is programmed to display temperature information as a function of temperature information signaled by the temperature sensor.

10. The system of claim 9, wherein the indicator device is adapted to display a current temperature sensed by the temperature sensor.

11. The system of claim 9, wherein the indicator device is adapted to display a change in a temperature sensed by the temperature sensor on the display screen.

12. The system of claim 1, further comprising:

a detection circuit adapted to detect the presence of a needle in the port chamber based upon information from the temperature sensor and to prompt operation of the indicator device.

13. The system of claim 12, wherein the detection circuit is adapted to compare a current temperature sensed by the temperature sensor with a set point temperature.

14. The system of claim 13, wherein the set point temperature is a predetermined value.

15. The system of claim 13, wherein the set point temperature is a previous temperature sensed by the temperature sensor.

16. The system of claim 13, wherein the detection circuit is adapted to prompt operation of the indicator device upon determining that the current temperature is less than the set point temperature.

17. The system of claim 13, wherein the detection circuit is adapted to prompt operation of the indicator device upon determining that the current temperature is decreasing relative to the set point temperature over a predetermined time period.

18. A method of monitoring an implantable therapeutic substance delivery device, the method comprising:

providing an implantable liquid therapeutic substance delivery device for delivering a therapeutic substance to a delivery site within a patient, the delivery device including;

a housing maintaining a reservoir for containing the therapeutic substance;

a fill port assembly including a port chamber in fluid communication with the reservoir, the fill port assembly further including a septum disposed across the port chamber to fluidly seal the port chamber relative to an exterior of the device;

sensing information relating to a temperature of the port chamber; and

determining whether the sensed information is indicative of a presence of a needle within the port chamber.

19. The method of claim 18, further comprising:

controlling an indicator device based upon the determination.

20. The method of claim 19, wherein controlling an indicator device includes prompting operation of the indicator device upon determining that the sensed information is indicative of a presence of a needle within the port chamber.

21. The method of claim 19, wherein the indicator device includes a sound generator maintained by the housing.

22. The method of claim 19, wherein the indicator device includes a display screen provided as part of an external programmer in wireless communication with the delivery device.

23. The method of claim 22, wherein prompting operation of the indicator device includes causing the display screen to display the current temperature sensed by the temperature sensor.

24. The method of claim 22, wherein prompting operation of the indicator device includes causing the display screen to display a change in a temperature sensed by the temperature sensor over time.

25. The method of claim 18, wherein determining whether the sensed information is indicative of a presence of a needle within the port chamber is based upon a determination that a liquid at a temperature below a temperature of the delivery device is being injected into the port chamber.

26. The method of claim 18, wherein determining whether the sensed information is indicative of a presence of a needle with the port chamber includes:

comparing a currently sensed temperature with a set point temperature.

27. The method of claim 18, wherein determining whether the sensed information is indicative of a presence of a needle within the port chamber includes:

recording a first temperature sensed by the temperature sensor as the set point temperature;

wherein the currently sensed temperature is obtained after recording the first temperature.

28. The method of claim 18, further comprising:

providing a syringe assembly including a needle fluidly connected to a supply of liquid;

maintaining the supply of liquid at a temperature below 85°

F;

attempting to percutaneously access the port chamber with the needle;

injecting a volume of the liquid through the needle; and

sensing a decrease in temperature at the temperature sensor when the needle is within the port chamber immediately after the step of injecting the volume of liquid.

29. The method of claim 28, wherein a decrease in temperature is not sensed at the temperature sensor immediately after the step of injecting a volume of liquid when the needle is not located within the port chamber during the step of injecting of volume of liquid through the needle.

30. The method of claim 28, wherein immediately prior to the step of percutaneously accessing the port chamber, the liquid is stored at approximately room temperature and the port chamber has a temperature approximating a bodily temperature of the patient.

31. A system for monitoring an implantable medical device, the′

system comprising;

an implantable liquid therapeutic substance delivery device for delivering a liquid therapeutic substance to a delivery site of a patient, the delivery device including;

a housing maintaining a reservoir for containing the therapeutic substance;

a fill port assembly including a septum exteriorly fluidly sealing a port chamber otherwise in fluid communication with the reservoir;

means for sensing information relating to a temperature of the port chamber; and

indicator means electronically coupled to the sensing means for indicating to a clinician information indicative of a needle being in the port chamber based upon information signaled from the sensing means.

32. The system of claim 31, wherein the sensing means is a temperature sensor.