Pressure switches, transmitters, systems, and methods for monitoring a pressure at a tissue site

• US 8,603,013 B2
• Filed: 03/13/2009
• Issued: 12/10/2013
• Est. Priority Date: 03/13/2008
• Status: Active Grant

• Current Assignee: KCI Licensing Incorporated (3M Company)
• Original Assignee: KCI Licensing Incorporated (3M Company)
• Inventors: Randolph, Larry Tab
• Primary Examiner(s): DOUGHERTY, SEAN PATRICK
• Application Number:
  US12/404,067
• Publication Number:
  US 20090234249A1
• Time in Patent Office: 1,733 Days
• Field of Search: 600/587, 600/592
• US Class Current: 600/592
• CPC Class Codes: A43B 3/34 with electrical or electronic arrangements
• CPC Class Codes: A43B 7/00 Footwear with health or hygienic arrangements
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/1036 Measuring load distribution, e.g. podologic studies
• CPC Class Codes: A61B 5/447 specially adapted for aiding the prevention of ulcer or pressure sore development, i.e. before the ulcer or sore has developed
• CPC Class Codes: A61B 5/6807 Footwear
• CPC Class Codes: A61B 5/6829 Foot or ankle
• CPC Class Codes: A61H 2201/164 Feet or leg, e.g. pedal
• CPC Class Codes: A61H 9/0057 Suction suction kneading A61H7/008
• CPC Class Codes: Y10T 156/1052 with cutting, punching, tearing or severing

Abstract

Apparatuses, systems, and methods for monitoring a pressure exerted on a tissue site are provided. In one embodiment, an apparatus includes a pressure switch adapted for placement adjacent the tissue site. The pressure switch includes an antenna operable to receive a first signal, a diode disposed adjacent the antenna, and a membrane covering the antenna and the diode. The membrane is movable from an unpressed position to a pressed position when a force is exerted on the membrane to cause electrical communication between the antenna and the diode. The antenna is operable to send a second signal when the membrane is in the pressed position. The apparatus may also include a transmitter operable to emit the first signal to the antenna. The transmitter may output an alert when the transmitter receives the second signal.

Claims

1. A system for monitoring a pressure exerted on a tissue site, the system comprising:

a transmitter operable to propagate a first signal, the first signal being a radio frequency signal, and emitting an alert when the transmitter receives a second signal in response to the first signal; and

a pressure switch adapted for placement adjacent the tissue site and to be responsive to a force applied at the tissue site, the pressure switch comprising;

an antenna operable to receive the first signal and propagate the second signal;

a diode disposed adjacent the antenna and electrically connected to the antenna to rectify the second signal;

a switch electrically connected to the antenna and the diode for completing a circuit when closed; and

a membrane covering the antenna and the diode, the membrane movable from an unpressed position to a pressed position when the force is exerted on the membrane to close the switch;

whereby the antenna propagates the second signal when the membrane is in the pressed position.

2. The system of claim 1, wherein the transmitter vibrates when the transmitter receives the second signal.

3. The system of claim 1, wherein the antenna is formed from a conducting conduit, and wherein the conducting conduit forms a spiral.

4. The system of claim 1, wherein the switch comprises a gap between the antenna and the diode, and a conductive material on an antenna-facing side of the membrane to electrically close the gap when the membrane is in the pressed position.

5. The system of claim 1, wherein the membrane moves from the pressed position to the unpressed position when at least a portion of the force is removed from the membrane.

6. The system of claim 1, wherein the membrane is shaped to form a dome.

7. The system of claim 1, wherein the pressure switch is a passive device.

8. The system of claim 1, wherein the pressure switch further comprises:

an adhesive layer adapted to adhere the pressure switch adjacent the tissue site, and

wherein the antenna is disposed between the adhesive layer and the membrane.

9. The system of claim 1, wherein the pressure switch further comprises:

an adhesive layer adapted to adhere the pressure switch to the tissue site, and

wherein the antenna is disposed between the adhesive layer and the membrane.

10. The system of claim 1, wherein the pressure switch further comprises:

a padding layer, and

wherein the antenna and the diode are disposed between the padding layer and the membrane.

11. The system of claim 1, wherein the pressure switch further comprises:

a padding layer formed from a gel, and

wherein the antenna and the diode are disposed between the padding layer and the membrane.

12. The system of claim 1, wherein the pressure switch further comprises:

an adhesive layer adapted to adhere the pressure switch adjacent the tissue site, wherein the antenna is disposed between the adhesive layer and the membrane; and

a padding layer disposed between the adhesive layer and the antenna.

13. The system of claim 1, wherein:

the antenna is formed from a conducting conduit,

the conducting conduit forms a spiral,

the switch includes a gap between the antenna and the diode, and a conductive material on an antenna-facing side of the membrane, and

the pressure switch further comprises;

an adhesive layer adapted to adhere the pressure switch adjacent the tissue site, wherein the antenna is disposed between the adhesive layer and the membrane; and

a padding layer disposed between the adhesive layer and the antenna.

14. A pressure switch for monitoring a pressure exerted on a tissue site and adapted for placement adjacent the tissue site and to be responsive to a force applied at the tissue site, the pressure switch comprising:

an antenna operable to receive a first radio frequency signal and propagate a second radio frequency signal in response to the first radio frequency signal;

a diode disposed adjacent the antenna and electrically connected to the antenna to rectify the second radio frequency signal;

a switch electrically connected to the antenna and the diode for completing a circuit when closed; and

a membrane covering the antenna and the diode, the membrane movable from an unpressed position to a pressed position when the force is exerted on the membrane to close the switch;

whereby the antenna propagates the second radio frequency signal when the membrane is in the pressed position.

15. The pressure switch apparatus of claim 14 further comprising:

a tactile feedback device operable to output a tactile alert to a patient when the second radio frequency signal is received;

wherein the tactile feedback device is adjacent the pressure switch.

16. The pressure switch of claim 15, wherein the tactile feedback device is coupled to the pressure switch.

17. The pressure switch of claim 15, wherein the tactile feedback device and the pressure switch are located in an off-loading boot.

18. The pressure switch of claim 15, wherein the tactile alert is vibration.

19. The pressure switch of claim 15, wherein the tactile alert is electrical stimulation.