DETECTING NEEDLE ENTRY INTO A PORT OF AN INFUSION DEVICE

• US 20080243093A1
• Filed: 03/29/2007
• Published: 10/02/2008
• Est. Priority Date: 03/29/2007
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Sarkinen, Scott A., Kalpin, Scott L.
• Granted Patent: US 7,942,863 B2
• Time in Patent Office: Days
• US Class Current: 604/288.02
• CPC Class Codes: A61B 17/3403 Needle locating or guiding means guides for suture needles A61B17/0482; guiding or tracking by nuclear magnetic resonance G01R33/285
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61M 2039/0244 having means for detecting an inserted needle
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 2209/045 for filling, e.g. for filling reservoirs
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/16831 Monitoring, detecting, signalling or eliminating infusion flow anomalies low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066
• CPC Class Codes: A61M 5/427 Locating point where body is to be pierced, e.g. vein location means using ultrasonic waves, injection site templates

Abstract

Systems for detecting needle insertion into a port chamber of an implantable medical device include a pressure sensor. The system detects characteristic pressure profiles associated with needle insertion into the port chamber through a septum and may generate a sensory cue to a clinician that proper needle placement has been achieved. Methods for detecting needle insertion into a port chamber of an implantable medical device includes detecting characteristic pressure profiles associated with needle insertion into the port chamber through a septum.

Claims

1. A method for detecting insertion of a needle into a port chamber of an implantable infusion device, the device including a port assembly defining the port chamber, the port assembly having a septum disposed across the port chamber to fluidly seal the port chamber relative to an exterior of the device, the method comprising:

sensing a pressure change in the port chamber; and

,

determining whether the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber.

2. The method of claim 1, wherein determining whether the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber comprises determining whether the sensed pressure change reflects a transient pressure increase in the chamber.

3. The method of claim 2, wherein determining whether the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber further comprises determining whether the pressure in the chamber returns, within 5 seconds, to a level substantially similar to that prior to the transient pressure increase.

4. The method of claim 2, wherein determining whether the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber further comprises determining whether the pressure in the chamber returns, within 2 seconds, to a level substantially similar to that prior to the transient pressure increase.

5. The method of claim 2, wherein determining whether the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber further comprises determining whether the pressure in the chamber returns, in a logarithmic decay profile over time, to a level substantially similar to that prior to the transient pressure increase.

6. The method of claim 1, further comprising:

identifying a characteristic transient pressure pattern profile associated with insertion of the needle through the septum into the port chamber,

wherein determining whether the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber comprises comparing the sensed pressure change to the characteristic transient pressure pattern profile.

7. The method of claim 1, further comprising:

generating a sensory cue if the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber.

9. The method of claim 7, wherein generating the sensory cue comprises generating the sensory cue from a second device, the second device being in wireless communication with the infusion device.

10. The method of claim 9, wherein generating the sensory cue from the second device comprises generating the cue from a programmer device.

8. The method of clam 7, wherein generating the sensory cue comprises generating an audible cue.

11. An implantable infusion device comprising:

a housing;

a port assembly defining a port chamber, the port assembly including a septum disposed across the chamber to fluidly seal the port chamber relative to an exterior of the housing, the port assembly being disposed in the housing such that the chamber is accessible by a needle inserted through the opening and the septum from the exterior of the housing;

a pressure sensor in fluid communication with the port chamber; and

,

electronics disposed in the housing and operably coupled to the pressure sensor, the electronics including a computer readable medium containing instructions that when implemented cause the device to detect, via the pressure sensor, a transient pressure increase in the port chamber associated with insertion of a needle into the port chamber.

12. The device of claim 11, wherein the pressure sensor is operably disposed in the port chamber.

13. The device of claim 11, further comprising a reservoir in fluid communication with the port chamber.

14. The device of claim 13, wherein the pressure sensor is operably disposed in the reservoir.

15. The device of claim 11, wherein the port assembly is a refill port assembly.

16. The device of claim 11, wherein the port assembly is a catheter access port assembly.

17. A method comprising:

inserting a needle into a patient to access a port chamber defined by a port assembly of an infusion device implanted in the patient, the port chamber being accessible from an exterior of the infusion device through a septum disposed across the port chamber to fluidly seal the port chamber relative to the exterior of the device;

sensing a pressure change in a port chamber;

determining whether the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber; and

generating a sensory cue if the sensed pressure change is indicative of insertion of the needle through the septum into the port chamber.

18. The method of claim 17, further comprising alerting the device that a needle is to be inserted into the port chamber.

19. The method of claim 17, further comprising (i) delivering fluid through the needle, and (ii) determining whether the sensed pressure change is indicative of fluid being injected into the chamber.

20. The method of claim 19, further comprising generating a sensory cue if the sensed pressure change is not indicative of fluid being injected into the chamber.