Reducing nuisance alarms

• US 8,792,949 B2
• Filed: 03/06/2009
• Issued: 07/29/2014
• Est. Priority Date: 03/31/2008
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Baker, Clark R. Jr.
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): Pani, John
• Application Number:
  US12/399,304
• Publication Number:
  US 20090247848A1
• Time in Patent Office: 1,971 Days
• Field of Search: 600/300, 600/301, 600309-344
• US Class Current: 600/323
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take 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 40/63 for local operation
• CPC Class Codes: G16H 40/67 for remote operation

Abstract

Embodiments disclosed herein may describe systems and methods for reducing nuisance alarms using probability and/or accuracy of a measured physiological parameter, such as the pulse rate or SpO2 measurement generated by a pulse oximeter. Embodiments may include methods for adjusting a predetermined alarm threshold based on the probability distribution of the estimated pulse rate and/or oxygen saturation of a patient'"'"'s blood.

Claims

1. A pulse oximetry system configured to generate an alarm indicating that a physiological parameter has exceeded a predetermined threshold, the pulse oximetry system comprising:

an oxygen saturation module for;

calculating a first estimated value of the physiological parameter and a second estimated value of the physiological parameter;

an accuracy module for;

calculating a first accuracy of the first estimated value and a second accuracy of the second estimated value;

determining that the second estimated value of the physiological parameter exceeds the predetermined threshold; and

comparing the second accuracy to the first accuracy to determine whether accuracy data has degraded; and

an alarm module for;

based on determining by the accuracy module that the accuracy data has degraded, calculating a delay time period; and

delaying generating the alarm for the calculated delay time period.

2. The pulse oximetry system of claim 1, wherein the oxygen saturation module is further for:

after the delay time period, calculating a third estimated value of the physiological parameter based at least in part upon new data;

and wherein the alarm module is further for;

when the third estimated value of the physiological parameter exceeds the predetermined threshold, generating the alarm.

3. The pulse oximetry system of claim 1, wherein the accuracy module is further for determining that a third accuracy exceeds a predetermined accuracy range.

4. The pulse oximetry system of claim 1, wherein the oxygen saturation module is further for:

after a predetermined time period, calculating a third estimated value of the physiological parameter based at least in part upon new data; and

determining that the third estimated value of the physiological parameter exceeds the predetermined threshold;

wherein the accuracy module is further for;

calculating a third accuracy of the third estimated value based at least in part upon new data; and

determining that the third accuracy does not exceed a predetermined accuracy range; and

wherein the alarm module is further for;

generating the alarm.