SPOT CHECK MEASUREMENT SYSTEM

• US 20180310822A1
• Filed: 04/27/2018
• Published: 11/01/2018
• Est. Priority Date: 04/28/2017
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Indorf, Keith Ward, Frey, Sebastian T., Muhsin, Bilal, Chandran, Prashanth Rengaswamy, Chinchalkar, Mihir, Iyengar, Prashanth
• Granted Patent: US 10,856,750 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 5/0015 characterised by features of the telemetry system
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/4842 Monitoring progression or stage of a disease
• CPC Class Codes: A61B 5/6802 Sensor mounted on worn items
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6838 Clamps or clips
• CPC Class Codes: A61B 5/72 Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61B 5/7405 using sound
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

A portable spot-check system configured to assess the validity of a measured physiological parameter. The spot-check device can take into consideration a variety of factors to determine whether a valid measurement exists. For instance, the considerations can include signal stability, interference, signal IQ, patient movement, sensor position, timing of that measurement, comparison to previous or acceptable measurements, cancellation of measurement by the patient, confidence of the measurement, etc. The spot-check device can track a number of valid measurements. In some instances, the spot-check device is configured to provide a specified number of available measurements. If a valid measurement is recorded, the spot-check device can decrement the remaining number of available measurements.

Claims

1. A pulse oximetry monitor configured to perform a spot-check measurement of a physiological parameter, the monitor comprising:

a driver circuit that drives one or more emitters of an optical sensor at multiple wavelengths of light to cause the one or more emitters to transmit the multiple wavelengths of light through body tissue of a patient;

a hardware processor in communication with the sensor, the hardware processor configured to;

determine a number of remaining spot-check credits;

based at least in part on a determination that the number of spot-check credits satisfies a threshold, initiate a spot-check measurement by obtaining a signal from the optical sensor;

compute the spot-check measurement based on the signal;

assess a validity of the spot-check measurement;

based at least in part on a determination that the spot-check measurement is valid, update the number of remaining spot-check credits; and

output the spot-check measurement to a display of the pulse oximetry monitor.

2. The monitor of claim 1, wherein to assess the validity of the spot-check measurement, the processor is configured to assess a validity of the signal obtained from the optical sensor.

3. The monitor of claim 2, wherein to assess the validity of the signal the processor is configured to assess a quality of the signal, wherein the quality of the signal is based at least in part on a combination of one or more of a signal IQ, a signal stability, or a signal strength of the signal obtained from the optical sensor.

4. The monitor of claim 3, wherein the processor is configured to determine the that spot-check signal is valid based at least in part on a determination that the signal quality of the signal satisfied a signal quality threshold for a least a threshold portion of a time window during which the measurement was taken.

5. The monitor of claim 1, wherein the hardware processor is further configured to compute an early warning score based on contributor scores derived from the spot-check measurement and a plurality of other physiological parameter measurements, and output in a single region of the display the early warning score together with the contributor scores or a trend of prior early warning scores.

6. A method of performing a spot-check measurement of a physiological parameter, the method comprising:

under control of a hardware processor of a patient monitor,

determining a number of remaining spot-check credits associated with a physiological sensor configured to be used to measure a physiological parameter of a patient;

based at least in part on a determination that the number of spot-check credits satisfies a threshold, initiating a spot-check measurement in conjunction with a sensor;

receiving a signal indicative of the spot-check measurement from the physiological sensor;

computing the spot-check measurement based on the signal;

assessing a validity of the spot-check measurement;

based at least in part on a determination that the measurement is valid, updating the number of remaining spot-check credits; and

outputting the spot-check measurement for presentation to a clinician.

7. The method of claim 6, said assessing the validity of the signal comprises assessing a quality of the signal received from the sensor.

8. The method of claim 6, wherein said assessing the validity of the spot-check measurement comprises comparing the measurement to an expected or previously determined measurement.

9. The method of claim 6, wherein said assessing the validity of the spot-check measurement, comprises determining that a cancellation condition does not exist.

10. The method of claim 6, further comprising determining the number of remaining spot-check credits in response to a request to initiate the spot-check measurement.

11. A medical device configured to receive a physiological signal from a physiological sensor coupled with a patient and to perform a spot-check measurement based on the physiological signal, the medical device comprising:

a circuit board comprising circuitry configured to receive the physiological signal either from a cable connected to the physiological sensor or wirelessly from the physiological sensor;

a display in electrical communication with the circuit board;

a speaker in electrical communication with the circuit board;

a memory device in electrical communication with the circuit board, the memory device comprising executable instructions stored thereon; and

a processor in electrical communication with the circuit board, the processor configured to implement the executable instructions so as to;

measure a plurality of physiological parameter values from the physiological signal;

output the physiological parameter values to the display;

detect that the physiological sensor has been disconnected from the patient;

select a currently-displayed one of the physiological parameter values as the spot-check measurement upon detecting that the physiological sensor has been disconnected from the patient;

freeze the currently-displayed one of the physiological parameter values on the display; and

output audio of the spot-check measurement to the speaker.

12. The medical device of claim 11, wherein the processor is further configured to lock the medical device in spot-check mode so that continuous measurements are not able to be calculated by the medical device when in the spot-check mode.

13. The medical device of claim 11, wherein the processor is further configured to select a plurality of additional spot-check measurements and to output a graph of the spot-check measurement and the additional spot-check measurements on the display, the graph representing a trend of the spot-check measurement and the additional spot-check measurements.

14. The medical device of claim 13, wherein the processor is further configured to cause the display to output a user interface control together with the spot-check measurement, the user interface control selectable by a user to permit a user to overwrite the spot-check measurement with a manual measurement.

15. The medical device of claim 11, wherein the processor is further configured to

measure a second plurality of physiological parameter values from the physiological signal;

select one of the second plurality of physiological parameter values as a second spot-check measurement upon said detecting that the physiological signal has been disconnected from the patient;

output audio of the second spot-check measurement to the speaker; and

output the second spot-check measurement to the display.

16. The medical device of claim 15, wherein the processor is further configured to:

calculate a contributor score for each of the spot-check measurement and the second spot-check measurement;

derive an early warning score at least in part from the contributor scores; and

output the contributor scores and the early warning score together in a group on the display, apart from the spot-check measurement and the second spot-check measurement.

17. A method for using a medical device to perform a spot-check measurement, the method comprising:

by a medical device comprising electronic hardware;

receiving a physiological signal from a sensor coupled with a patient;

measuring, from the physiological signal, a plurality of first values of a first physiological parameter and a plurality of second values of a second physiological parameter;

detecting that the sensor has been disconnected from the patient or that a clinician has selected a display input requesting spot-check measurements;

selecting one of the first values and one of the second values as the spot-check measurements upon either detecting that the physiological sensor has been disconnected from the patient or upon detecting that the clinician has selected the display input requesting the spot-check measurements; and

outputting the spot-check measurements audibly or to a display.

18. The method of claim 17, further comprising outputting a trend graph of the spot-check measurements in response to selection of one of the spot-check measurements by the clinician.

19. The method of claim 17, further comprising, in response to said detecting that the sensor has been disconnected from the patient or that a clinician has selected an input requesting spot-check measurements, calculating an early warning score based at least in part on the spot-check measurements, and outputting the early warning score to the display.

20. The method of claim 17, further comprising, prior to said receiving,

outputting an option to place the medical device in spot-check mode;

receiving a selection of the option to place the medical device in the spot-check mode; and

subsequent to receiving the selection of the option, rebooting the medical device in spot-check mode and not permitting continuous monitoring.