Incontinence detection system

• US 10,349,881 B1
• Filed: 05/01/2018
• Issued: 07/16/2019
• Est. Priority Date: 02/21/2018
• Status: Active Grant

• Current Assignee: Hill-Rom Services Incorporated (Baxter International Inc.)
• Original Assignee: Hill-Rom Services Incorporated (Baxter International Inc.)
• Inventors: Monson, Gavin M., Nusair, Marwan, Canter, Joseph T., Christie, John D., Tallent, Dan, Voll, James D., Weidman, Bryan
• Primary Examiner(s): Fan, Hongmin
• Application Number:
  US15/968,029
• Time in Patent Office: 441 Days
• CPC Class Codes: A61B 2503/08 Elderly
• CPC Class Codes: A61B 2560/0468 Built-in electrodes
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/202 Assessing bladder functions, e.g. incontinence assessment
• CPC Class Codes: A61B 5/207 Sensing devices adapted to collect urine
• CPC Class Codes: A61B 5/6808 Diapers
• CPC Class Codes: A61B 5/6892 Mats
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/7465 Arrangements for interactive communication between patient and care services, e.g. by using a telephone network telemetry of measured physiological signal A61B5/0002
• CPC Class Codes: A61B 90/98 using electromagnetic means, e.g. transponders
• CPC Class Codes: A61F 13/42 with wetness indicator or alarm
• CPC Class Codes: A61F 2013/15154 for hospitalised patients
• CPC Class Codes: A61F 2013/424 having an electronic device
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications
• CPC Class Codes: G08B 21/20 responsive to moisture
• CPC Class Codes: H01H 35/18 Switches operated by change of liquid level or of liquid density, e.g. float switch by magnet carried on a float H01H36/02

Abstract

A system for detecting an incontinence event includes a pad which is deployable on a mattress and which, as deployed, has an open circuit comprised of a first conductor extending from a first terminal of an RFID inlay, and a second conductor extending from a second terminal of the RFID inlay. The system also includes an RFID reader subsystem having an array of two or more spatially distributed antennas. The detection system commands spatially and temporally varying transmission of energy from the antenna array at a variety of powers and frequency settings. The detection system monitors the antenna array for a return signal resulting from the transmission. The return signal has a moisture status indicator which indicates whether or not liquid is present on the pad. The detection system also causes communication of a WET or DRY status to a destination. The reported WET or DRY status depends on the moisture status indicator.

Claims

1. A system for detecting an incontinence event comprising:

a pad having an open circuit comprised of a first conductor extending from a first terminal of an RFID inlay, and a second conductor extending from a second terminal of the RFID inlay;

an RFID reader subsystem having a processor and two or more antennas, each antenna being adapted to radiate and receive electromagnetic energy, the system adapted to;

A) select;

1) an antenna pair i from an ordered list of i_max antenna pairs in which one member of the pair is a send antenna and the other member is a receive antenna,

2) a transmit power j from an ordered list of j_max transmit powers, and

3) a frequency k from an ordered list of k_max frequencies,

B) command transmission of energy from the send antenna of the selected antenna pair i at the selected power j and frequency k, and

C) repeat A and B with i replaced by an incremented value of i, j replaced by an incremented value of j, and k replaced by an incremented value of k provided that if any of the incremented values of i, j, or k exceeds i_max, j_max, k_max respectively, the excessive value is instead replaced by one.

2. The detection system of claim 1 wherein:

the ordered list of antenna pairs includes at least one occurrence of every possible send/receive pairing.

3. The detection system of claim 1 wherein:

the ordered list of antenna pairs includes a first ordered sublist of antenna pairs and a second ordered sublist of antenna pairs, the ordering of the second sublist differing from the order of the first sublist.

4. The detection system of claim 3 wherein the ordering of the second sublist is an offset ordering.

5. The detection system of claim 1 wherein:

the ordered list of transmit powers includes at least one transmit power repetition.

6. The detection system of claim 1 wherein no quotient of any two of i_max, j_max, k_max is an integer.

7. The detection system of claim 1 wherein the list of antenna pairs has N_AP members, the list of transmit powers has N_P members, the list of frequencies has N_F members, and no quotient of any two of N_AP, N_P, and N_F is an integer.

8. The detection system of claim 1 wherein execution of step B is selectively delayed relative to the immediately preceeding execution of step B.

9. The detection system of claim 1 wherein execution of step B is not carried out until a predesignated interval of time has elapsed since the immediately preceeding execution of step B.

10. The detection system of claim 1 wherein the list of power settings includes N_P members representing N_UP unique power settings and wherein N_UP is less than N_P.

11. The detection system of claim 1 wherein the list of frequencies includes N_F members representing N_UF unique frequencies and wherein the order of the frequencies is nonmonotonic.

12. The detection system of claim 1 wherein the system:

monitors the receive antenna for a return signal from the inlay, the return signal having an information content which includes at least a moisture status indicator which distinguishes between perceived presence and perceived absence of moisture at the pad and;

issues a report to a destination, the report including a WET or DRY indication based on the status indicator of one or more return signals.

13. The detection system of claim 12 wherein:

the report is based on the information content of a sample of one or more return signals;

the moisture status indicator has a wet state corresponding to the perceived presence of moisture at the pad and a dry state corresponding to the perceived absence of moisture at the pad; and

the indication of WET or DRY depends on the state of the moisture status indicator in the sample of return signals.

14. The detection system of claim 12 wherein the indication of WET or DRY is based on a sample of more than one return signal and does not require the state of the moisture status indicator to be the same in all of the return signals of the sample.

15. The detection system of claim 12 wherein the destination comprises one or more of an indicator light and a nurse call system.

16. The detection system of claim 12 comprising multiple pads each having an identity, and wherein the information content of the return signal from each pad includes a pad identifier and the report includes a WET or DRY indication accompanied by the pad identifier.

17. The detection system of claim 1 wherein:

if the circuit is open the moisture indicator is in a state indicating the absence of moisture at the pad; and

if the circuit is closed the moisture indicator is in a state indicating the presence of moisture at the pad.

18. The detection system of claim 1 wherein the inlay comprises an inlay processor connected to the first and second terminals and to an inlay antenna.

19. The detection system of claim 1 wherein the inlay processor is connected to the first and second terminals by first and second electrical paths respectively, at least one of the electrical paths being configured to guard against RF that impinges on one or both of the conductors from coupling to the inlay antenna.

20. The detection system of claim 19 wherein the at least one electrical path is configured to guard against RF that impinges on one or both of the conductors from coupling to the inlay antenna by virtue of one or both of:

having a nonlinear geometry; and

including a resistor.

21. The detection system of claim 1 wherein step C is conditioned by:

if the selected ith antenna pair is considered to be unsatisfactory, refraining from future use of the unsatisfactory antenna pair for a specified period of time, or for a specified number of passes through steps A and B and instead proceeding to the next antenna pair not identified as being unsatisfactory.

22. The detection system of claim 1 wherein step C is conditioned by:

if the selected jth transmit power is considered to be unsatisfactory, refraining from future use of the unsatisfactory transmit power for a specified period of time, or for a specified number of passes through steps A and B and instead proceeding to the next transmit power not identified as being unsatisfactory.

23. The detection system of claim 1 wherein step C is conditioned by:

if the combination of the selected ith antenna pair and jth transmit power is considered to be unsatisfactory, refraining from future use of the unsatisfactory combination for a specified period of time, or for a specified number of passes through steps A and B, and instead proceeding to the next combination not identified as being unsatisfactory.

24. A system for detecting an incontinence event comprising:

a pad having an open circuit comprised of a first conductor extending from a first terminal of an RFID inlay, and a second conductor extending from a second terminal of the RFID inlay;

an RFID reader subsystem having a processor and two or more antennas, each antenna being adapted to radiate and receive electromagnetic energy, the system adapted to;

A) select;

1) an antenna pair from a list of antenna pairs in which one member of the pair is a send antenna and the other member is a receive antenna,

2) a transmit power from a list of transmit powers, and

3) a frequency from an ordered list of frequencies,

B) command transmission of energy from the send antenna of the selected antenna pair at the selected frequency and power, and

C) repeat A and B with the antenna pair replaced by a newly selected antenna pair, the transmit power replaced by a newly selected transmit power and the frequency replaced by a newly selected frequency provided that the newly selected antenna pair or the combination of the newly selected antenna pair and newly selected transmit power is an antenna pair or combination determined to be satisfactory.