Dual-mode physiologic monitoring systems and methods
In some embodiments, a wearable physiologic monitor comprises an application-specific integrated circuit (ASIC) including signal conditioning circuitry, a real-time clock, digital control logic, and mode-selection logic for setting an operating mode of the ASIC to a stand-alone mode or a peripheral mode. In the stand-alone mode, the digital control logic periodically stores data packets including multiple sensor data types in a digital memory such as a removable flash memory card. In the peripheral mode, the data packets are transmitted to a microcontroller for processing. The monitor includes sensors such as electrocardiogram (ECG) electrodes, accelerometers, and a temperature sensor, some of which may be integrated on the ASIC. The same basic chip design may be used in the stand-alone mode in disposable patches, and in the peripheral mode in bedside devices. The operating mode may be chosen at monitor manufacture, by connecting input pins to mode-selection logic levels.
1. A physiologic monitoring system comprising:
a battery;
a plurality of electrocardiogram electrodes;
a digital memory; and
an integrated circuit connected to the battery, the plurality of electrocardiogram electrodes, and the digital memory, comprising:
a real-time clock for generating a set of real time indicators;
amplification and filtering circuitry for amplifying and filtering a set of physiologic electrical signals received from the plurality of electrocardiogram electrodes to generate a set of filtered electrical signals;
digital control logic connected to the real-time clock and the amplification and filtering circuitry; and
mode-selection logic connected to the digital control logic, for setting an operating mode of the integrated circuit to a mode selected from a stand-alone mode and a peripheral mode;
wherein, in the stand-alone mode, the digital control logic is configured to generate a set of time-stamped physiologic data packets from the set of real-time indicators and a set of digital electrocardiogram data derived from the filtered electrical signals, and
transmit the time-stamped data packets for storage in the digital memory; and
wherein, in the peripheral mode, the integrated circuit is configured to transfer physiologic data derived from the digital electrocardiogram data to a programmable microcontroller.
2. The system of claim 1 , wherein the operating mode of the integrated circuit is set to the stand-alone mode.
3. The system of claim 1 , wherein the operating mode of the integrated circuit is set to the peripheral mode.
4. The system of claim 3 , further comprising the programmable microcontroller connected to the integrated circuit.
5. The system of claim 1 , further comprising a set of integrated circuit mode-selection input pins connected to the mode-selection logic, wherein the mode-selection logic is configured to set the operating mode of the integrated circuit according to a set of logic levels of the mode-selection input pins.
6. The system of claim 5 , wherein the mode-selection input pins are bonded to a set of mode-selection logic levels.
7. The system of claim 1 , wherein the peripheral mode is a self-clocked peripheral mode, and wherein in the self-clocked peripheral mode the digital control logic is configured to generate the set of time-stamped physiologic data packets from the set of real-time indicators and the digital electrocardiogram data, and transmit the set of time-stamped data packets to the programmable microcontroller.
8. The system of claim 1 , wherein the peripheral mode is a passive peripheral mode, and wherein in the passive peripheral mode the digital control logic is substantially disabled.
9. The system of claim 1 , wherein the integrated circuit is integrated in a wearable patch configured to be attached to a subject's skin.
10. The system of claim 9 , wherein the plurality of electrodes are integrated in the wearable patch.
11. The system of claim 9 , wherein the patch comprises an encapsulant enclosing the integrated circuit.
12. The system of claim 9 , further comprising an adhesive for coupling the patch to a subject's skin.
13. The system of claim 1 , wherein the amplification and filtering circuitry comprises a pacemaker pulse detection circuit for detecting a set of pacemaker pulses sensed by the electrocardiogram electrodes.
14. The system of claim 1 , wherein the amplification and filtering circuitry comprises continuous-time analog filtering circuitry.
15. The system of claim 1 , wherein the amplification and filtering circuitry comprises switched capacitor filtering circuitry.
16. The system of claim 1 , wherein the amplification and filtering circuitry comprises a digital signal processor.
17. The system of claim 1 , further comprising a timing resonator coupled to the real-time clock, for sending a set of periodic timing pulses to the real-time clock.
18. The system of claim 17 , wherein the integrated circuit comprises the timing resonator.
19. The system of claim 1 , further comprising a physiologic temperature sensor for generating a set of subject temperature indicators, the digital control logic being connected to the temperature sensor, wherein in the stand-alone mode the digital control logic is configured to include in the time-stamped data packets a set of digital temperature data derived from the set of subject temperature indicators.
20. The system of claim 1 , further comprising an accelerometer for generating a set of subject acceleration indicators, wherein in the stand-alone mode the digital control logic is configured to include in the time-stamped data packets a set of digital acceleration data derived from the acceleration indicators.
21. The system of claim 20 , wherein the integrated circuit comprises the accelerometer.
22. The system of claim 1 , further comprising an impedance measurement circuit comprising an impedance measurement electrode, for generating a set of impedance indicators, wherein in the stand-alone mode the digital control logic is configured to include in the time-stamped data packets a set of digital impedance data derived from the impedance indicators.
23. The system of claim 1 , further comprising a pulse oximeter for generating a set of blood oxygen indicators, wherein in the stand-alone mode the digital control logic is configured to include in the time-stamped data packets a set of digital blood oxygen data derived from the blood oxygen indicators.
24. The system of claim 1 , further comprising a light detector for generating a set of ambient light intensity indicators, wherein in the stand-alone mode the digital control logic is configured to include in the time-stamped data packets a set of digital ambient light data derived from the ambient light intensity indicators.
25. The system of claim 1 , further comprising a sound detector for generating a set of ambient sound intensity indicators, wherein in the stand-alone mode the digital control logic is configured to include in the time-stamped data packets a set of digital ambient sound data derived from the ambient sound intensity indicators.
26. The system of claim 1 , further comprising an ionizing radiation detector for generating a set of ambient ionizing radiation indicators, wherein in the stand-alone mode the digital control logic is configured to include in the time-stamped data packets a set of digital ionizing radiation data derived from the ambient ionizing radiation indicators.
27. The system of claim 1 , further comprising a subject sensory indicator device connected to the digital control logic, for providing a sensory indication to a subject.
28. The system of claim 27 , wherein the sensory indicator device comprises a light-emitting device.
29. The system of claim 27 , wherein the sensory indicator device comprises a speaker.
30. The system of claim 29 , wherein the sensory indication comprises a voice prompt.
31. The system of claim 27 , wherein the digital control logic comprises physiologic condition detection logic connected to the sensory indicator device, the physiologic condition detection logic being configured to activate the sensory indicator device when a physiologic parameter value meets a predetermined condition.
32. The system of claim 27 , wherein the digital control logic comprises real-time detection logic connected to the sensory indicator device, the real-time detection logic being configured to activate the sensory indicator device when a current real time meets a predetermined condition.
33. The system of claim 1 , wherein the digital control logic comprises electrode fault detection logic connected to the plurality of electrocardiogram electrodes, for detecting an electrocardiogram electrode fault.
34. The system of claim 1 , further comprising an external event actuator, configured to generate an event signal in response to actuation by a subject, the digital control logic in the stand-alone mode being configured to include digital event data derived from the event signal in the time-stamped data packets.
35. The system of claim 1 , further comprising a wearable visual display connected to the digital control logic, for generating a display of data derived from the digital electrocardiogram data.
36. The system of claim 1 , wherein the set of time-stamped data packets include a first time-stamped data packet and a second time-stamped data packet, wherein the first time-stamped data packet and the second time-stamped data packet are temporally separated by a set of non-time-stamped physiologic data packets transmitted by the digital control logic in the stand-alone mode for storage in the digital memory.
37. The system of claim 1 , wherein the digital control logic in the stand-alone mode is configured to assemble the set of data packets according to a predetermined inter-packet time period, wherein each packet in the set of data packets is separated by the inter-packet time period from an immediately preceding data packet and an immediately subsequent data packet.
38. A physiologic monitoring system comprising:
a battery;
a set of physiologic sensors;
a digital memory; and
an integrated circuit connected to the battery, the set of physiologic sensors, and the digital memory, comprising:
a real-time clock for generating a set of real time indicators;
amplification and filtering circuitry for amplifying and filtering a set of electrical signals received from the set of physiologic sensors to generate a set of filtered electrical signals;
digital control logic connected to the real-time clock and the amplification and filtering circuitry; and
mode-selection logic connected to the digital control logic, for setting an operating mode of the integrated circuit to a mode selected from a stand-alone mode and a peripheral mode;
wherein, in the stand-alone mode, the digital control logic is configured to generate a set of time-stamped physiologic data packets from the set of real-time indicators and a set of digital physiologic data derived from the filtered electrical signals, and
transmit the time-stamped data packets for storage in the digital memory; and
wherein, in the peripheral mode, the integrated circuit is configured to transfer physiologic data derived from the digital physiologic data to a programmable microcontroller.
39. A physiologic monitoring integrated circuit comprising:
an integrated real-time clock for generating a set of real time indicators;
integrated amplification and filtering circuitry connected to a set of physiologic sensors, for amplifying and filtering a set of electrical signals received from the physiologic sensors to generate a set of filtered electrical signals;
integrated digital control logic connected to the real-time clock and the amplification and filtering circuitry; and
integrated mode-selection logic connected to the digital control logic, for setting an operating mode of the integrated circuit to a mode selected from a stand-alone mode and a peripheral mode;
wherein, in the stand-alone mode, the digital control logic is configured to generate a set of time-stamped physiologic data packets from the set of real- time indicators and a set of digital physiologic data derived from the filtered electrical signals, and
transmit the time-stamped data packets for storage in a digital memory; and
wherein, in the peripheral mode, the integrated circuit is configured to transfer data derived from the digital physiologic data to a programmable microcontroller.
40. A physiologic monitoring system comprising:
a set of physiologic sensors;
a digital memory; and
an integrated circuit connected to the set of physiologic sensors, and the digital memory, comprising:
real-time means for generating a set of real time indicators;
amplification and filtering means for amplifying and filtering a set of electrical signals received from the set of physiologic sensors to generate a set of filtered electrical signals;
digital control means connected to the real-time means and the amplification and filtering means; and
mode-selection means connected to the digital control means, for setting an operating mode of the integrated circuit to a mode selected from a stand-alone mode and a peripheral mode;
wherein, in the stand-alone mode, the digital control means is configured to generate a set of time-stamped physiologic data packets from the set of real-time indicators and a set of digital physiologic data derived from the filtered electrical signals, and
transmit the time-stamped data packets for storage in the digital memory; and
wherein, in the peripheral mode, the integrated circuit is configured to transfer physiologic data derived from the digital physiologic data to a programmable microcontroller.
41. A physiologic monitoring method comprising:
sensing a plurality of physiologic signals generated by a subject; and
employing an integrated circuit to generate a set of real time indicators;
amplify and filter the physiologic signals to generate a set of filtered electrical signals;
generate a set of digital physiologic data from the set of filtered electrical signals; and
process the set of digital physiologic data according to a setting of an operating mode of the integrated circuit to a mode selected from a stand-alone mode and a peripheral mode;
wherein, in the stand-alone mode, the integrated circuit is configured to generate a set of time-stamped physiologic data packets from the set of real-time indicators and the digital physiologic data, and
transmit the time-stamped data packets for storage in a digital memory; and
wherein, in the peripheral mode, the integrated circuit is configured to transfer data derived from the digital physiologic data to a programmable microcontroller.
42. The method of claim 41 , wherein the operating mode of the integrated circuit is set to the stand-alone mode.
43. The method of claim 41 , wherein the operating mode of the integrated circuit is set to the peripheral mode.
44. The method of claim 43 , further comprising connecting the programmable microcontroller to the integrated circuit.
45. The method of claim 41 , wherein setting the operating mode of the integrated circuit is performed according to a set of logic levels of a set of integrated circuit mode-selection input pins.
46. The method of claim 45 , wherein the mode-selection input pins are bonded to a set of mode-selection logic levels.
47. The method of claim 41 , wherein the peripheral mode is a self-clocked peripheral mode, and wherein in the self-clocked peripheral mode the integrated circuit is configured to generate the set of time-stamped physiologic data packets from the set of real-time indicators and the digital physiologic data, and transmit the set of time-stamped data packets to the programmable microcontroller.
48. The method of claim 41 , wherein the peripheral mode is a passive peripheral mode.
49. The method of claim 41 , wherein the integrated circuit is integrated in a wearable patch configured to be attached to a subject's skin.
50. The method of claim 49 , wherein the plurality of electrodes are integrated in the wearable patch.
51. The method of claim 49 , wherein the patch comprises an encapsulant enclosing the integrated circuit.
52. The method of claim 49 , further comprising coupling the patch to a subject's skin using a patch adhesive.
53. The method of claim 41 , farther comprising employing the integrated circuit to detect a set of pacemaker pulses.
54. The method of claim 41 , comprising employing continuous-time analog filtering circuitry to filter the physiologic signals.
55. The method of claim 41 , comprising employing switched-capacitor filtering circuitry to filter the physiologic signals.
56. The method of claim 41 , comprising employing a digital signal processor to filter the physiologic signals.
57. The method of claim 41 , farther comprising sending a set of periodic timing pulses from a timing resonator to a real-time clock configured to generate the set of real-time indicators.
58. The method of claim 57 , wherein the integrated circuit comprises the timing resonator.
59. The method of claim 41 , further comprising generating a set of subject temperature indicators, wherein in the stand-alone mode the integrated circuit is configured to include in the time-stamped data packets a set of digital temperature data derived from the set of subject temperature indicators.
60. The method of claim 41 , further comprising generating a set of subject acceleration indicators, wherein in the stand-alone mode the integrated circuit is configured to include in the time-stamped data packets a set of digital acceleration data derived from the acceleration indicators.
61. The method of claim 60 , wherein the integrated circuit comprises the accelerometer.
62. The method of claim 41 , further comprising generating a set of impedance indicators, wherein in the stand-alone mode the integrated circuit is configured to include in the time-stamped data packets a set of digital impedance data derived from the impedance indicators.
63. The method of claim 41 , further comprising generating a set of blood oxygen indicators, wherein in the stand-alone mode the integrated circuit is configured to include in the time-stamped data packets a set of digital blood oxygen data derived from the blood oxygen indicators.
64. The method of claim 41 , further comprising generating a set of ambient light intensity indicators, wherein in the stand-alone mode the integrated circuit is configured to include in the time-stamped data packets a set of digital ambient light data derived from the ambient light intensity indicators.
65. The method of claim 41 , further comprising generating a set of ambient sound intensity indicators, wherein in the stand-alone mode the integrated circuit is configured to include in the time-stamped data packets a set of digital ambient sound data derived from the ambient sound intensity indicators.
66. The method of claim 41 , further comprising generating a set of ambient ionizing radiation indicators, wherein in the stand-alone mode the integrated circuit is configured to include in the time-stamped data packets a set of digital ionizing radiation data derived from the ambient ionizing radiation indicators.
67. The method of claim 41 , further comprising providing a sensory indication to a subject.
68. The method of claim 67 , wherein the sensory indication comprises light.
69. The method of claim 67 , wherein the sensory indication comprises a sound.
70. The method of claim 69 , wherein the sensory indication comprises a voice prompt.
71. The method of claim 67 , further comprising selectively providing the sensory indication in response to determining that a physiologic parameter value derived from the set of digital physiologic data meets a predetermined condition.
72. The method of claim 67 , further comprising selectively providing the sensory indication in response to determining that a current real time meets a predetermined condition.
73. The method of claim 41 , further comprising employing the integrated circuit to detect an electrocardiogram electrode fault.
74. The method of claim 41 , further comprising receiving an input from an external event actuator configured to generate an event signal in response to actuation by a subject, the digital control logic in the stand-alone mode being configured to include digital event data derived from the event signal in the time-stamped data packets.
75. The method of claim 41 , further comprising generating a display of data derived from the digital electrocardiogram data on a wearable display connected to the integrated circuit.
76. The method of claim 41 , wherein the set of time-stamped data packets include a first time-stamped data packet and a second time-stamped data packet, wherein the first time-stamped data packet and the second time-stamped data packet are temporally separated by a set of non-time-stamped physiologic data packets transmitted by the integrated circuit in the stand-alone mode for storage in the digital memory.
77. The method of claim 41 , wherein the integrated circuit in the stand-alone mode is configured to assemble the set of data packets according to a predetermined inter-packet time period, wherein each packet in the set of data packets is separated by the inter-packet time period from an immediately preceding data packet and an immediately subsequent data packet.