SYSTEMS AND METHODS FOR PHYSIOLOGICAL EVENT MARKING

• US 20120143012A1
• Filed: 12/01/2010
• Published: 06/07/2012
• Est. Priority Date: 12/01/2010
• Status: Active Grant

• Current Assignee: Nellcor Puritan Bennett Ireland
• Original Assignee: Nellcor Puritan Bennett Ireland
• Inventors: Watson, James N., Addison, Paul Stanley, Sethi, Rakesh, Manning, Keith
• Granted Patent: US 9,357,934 B2
• Time in Patent Office: Days
• US Class Current: 600/300
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/02125 of pulse wave propagation time
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• 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: G01D 18/008 with calibration coefficients stored in memory
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

Systems and methods are provided for storing event markers. The value of a monitored physiological metric may be monitored and compared to a reference value. A patient monitoring system may compute a difference between a monitored metric and a reference value, and compare the difference to a threshold value to determine whether a physiological event has occurred. Based on the determination, a patient monitoring system may store an event marker, trigger a response, update a metric value, or perform any other suitable function.

Claims

1. A method for providing a physiological event marker, the method comprising:

receiving a physiological signal;

monitoring using electronic processing equipment at least one value derived from the physiological signal, wherein the at least one value comprises a combination of pulse rate, pulse wave area, pulse statistical moment, and/or DC offset;

determining using the electronic processing equipment that a physiological event has occurred based at least in part on the at least one value and based at least in part on at least one corresponding threshold; and

storing the physiological event marker indicative of when the physiological event occurred.

2. The method of claim 1, wherein the combination comprises a weighted sum.

3. The method of claim 1, further comprising triggering an alarm based at least in part on the occurrence of the physiological event.

4. The method of claim 1, further comprising triggering a recalibration of a medical monitoring apparatus based at least in part on the occurrence of the physiological event.

5. The method of claim 1, further comprising recording physiological data beginning at a time based at least in part on the occurrence of the physiological event.

6. The method of claim 1, wherein determining that the physiological event has occurred is based at least in part on a change in the at least one value.

7. The method of claim 6, wherein the at least one corresponding threshold is based at least in part on whether the change in the at least one value is positive or negative.

8. The method of claim 1, wherein the at least one corresponding threshold is based at least in part on calibration data.

9. The method of claim 1, wherein the at least one corresponding threshold is based at least in part on user input.

10. The method of claim 1, further comprising monitoring at least one auxiliary value derived from at least one auxiliary signal, wherein determining that a physiological event has occurred is further based at least in part on the auxiliary value.

11. The method of claim 10, wherein the auxiliary signal comprises a photoplethysmograph (PPG) signal, and wherein the physiological signal comprises a PPG signal, and wherein the at least one auxiliary value comprises a differential pulse transit time (DPTT) based at least in part on the physiological signal and on the auxiliary signal.

12. The method of claim 1, wherein the threshold is based at least in part on the monitored at least one value.

13. A system for providing a physiological event marker, the system comprising:

a sensing device;

a signal input configured to receive a physiological signal of a subject from the sensing device; and

electronic processing equipment coupled to the signal input and configured to;

monitor at least one value derived from the physiological signal, wherein the at least one value comprises a combination of pulse rate, pulse wave area, pulse statistical moment, and/or DC offset;

determine that a physiological event has occurred based at least in part on the at least one value and based at least in part on at least one corresponding threshold; and

store the physiological event marker indicative of when the physiological event occurred.

14. The system of claim 13, wherein the combination comprises a weighted sum.

15. The system of claim 13, wherein the electronic processing equipment is further configured to trigger an alarm based at least in part on the occurrence of the physiological event.

16. The system of claim 13, wherein the electronic processing equipment is further configured to recalibrate a medical monitoring apparatus based at least in part on the occurrence of the physiological event.

17. The system of claim 13, wherein the electronic processing equipment is further configured to record physiological data beginning at a time based at least in part on the occurrence of the physiological event.

18. The system of claim 13, further comprising:

an auxiliary sensing device, wherein the signal input is further configured to receive an auxiliary signal of the subject from the auxiliary sensing device, and wherein the electronic processing equipment is further configured to;

monitor at least one auxiliary value derived from the auxiliary signal, wherein determining that a physiological event has occurred is further based at least in part on the auxiliary value.

19. The system of claim 18, wherein the auxiliary signal comprises a photoplethysmograph (PPG) signal, and wherein the physiological signal comprises a PPG signal, and wherein the at least one auxiliary value further comprises a differential pulse transit time (DPTT) based at least in part on the physiological signal and on the auxiliary signal.

20. The system of claim 13, wherein the threshold is based at least in part on the monitored at least one value.