Physiological parameter system

• US 20050203352A1
• Filed: 03/08/2005
• Published: 09/15/2005
• Est. Priority Date: 03/08/2004
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Al-Ali, Ammar, Kiani, Massi E., Graybeal, John, Petterson, Michael
• Granted Patent: US 7,415,297 B2
• Time in Patent Office: Days
• US Class Current: 600/309
• CPC Class Codes: A61B 2560/0276 Determining malfunction
• CPC Class Codes: A61B 5/0836 Measuring rate of CO2 production
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• 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 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B

Abstract

A physiological parameter system has one or more parameter inputs responsive to one or more physiological sensors. The physiological parameter system may also have quality indicators relating to confidence in the parameter inputs. A processor is adapted to combine the parameter inputs, quality indicators and predetermined limits for the parameters inputs and quality indicators so as to generate alarm outputs or control outputs or both.

Claims

1. A physiological parameter system comprising:

a first parameter input responsive to a first physiological sensor;

a second parameter input responsive to a second physiological sensor;

a plurality of predetermined limits for said parameters; and

a processor adapted to combine said parameters and said limits so as to generate an alarm output.

2. The physiological parameter system according to claim 1 further comprising:

a variable threshold responsive to said second parameter, said alarm output responsive to said first parameter and said variable threshold.

3. The physiological parameter system according to claim 2 further comprising:

a predetermined limit related to said second parameter, wherein said alarm output is triggered below said variable threshold, and wherein said variable threshold is raised in response to said second parameter and said predetermined limit.

4. The physiological parameter system according to claim 3 wherein:

said first parameter is SpO₂, said second parameter is ETCO₂, and said variable threshold is a lower limit for SpO₂ that is raised in response to a downward trend in ETCO₂ at a rate greater than said predetermined limit.

5. The physiological parameter system according to claim 1 further comprising:

a pattern detector having a detection output responsive to said first parameter, said alarm output responsive to said detection output.

6. The physiological parameter system according to claim 5 further comprising:

a slope detector output responsive to said second parameter; and

a predetermined slope limit responsive to said slope detector output, wherein said alarm output is triggered only if said slope detector output exceeds said slope limit.

7. The physiological parameter system according to claim 6 wherein:

said first parameter is ETCO₂, said second parameter is SpO₂, and said alarm output is responsive to ETCO₂ morphology only when there is a sufficient downward trend in SpO₂.

8. A physiological parameter system comprising:

a parameter input responsive to a physiological sensor;

a quality indicator input relating to confidence in said parameter input;

a plurality of predetermined limits for said parameter input and said quality indicator input; and

a processor adapted to combine said inputs and said limits so as to generate a control output.

9. The controller according to claim 8 wherein said control output disables patient controlled analgesia when confidence in said parameter input is low.

10. The controller according to claim 9 wherein said control prevents said first parameter from disabling said patient controlled analgesia when confidence in said parameter is low.

11. A physiological parameter method comprising the steps of:

inputting a parameter responsive to a physiological sensor;

inputting a quality indicator related to data confidence for said parameter;

outputting a control signal from the combination of said parameter and said quality indicator,

wherein said control signal is adapted to affect the operation of a medical-related device.

12. The physiological parameter method according to claim 11 wherein said parameter and said quality indicator are derived from a pulse oximetry sensor, said outputting step comprising the substeps of:

configuring said control signal to conditionally disable said medical-related device;

regulating said control signal in response to said quality indicator.

13. The physiological parameter method according to claim 12 wherein said regulating substep comprises the substep of disabling said shut-off signal when confidence in said parameter is low.

14. The physiological parameter method according to claim 13 wherein said regulating substep comprises the substep of enabling said shut-off signal when confidence in said parameter is low.