Physiological parameter tracking system

• US 8,385,995 B2
• Filed: 08/06/2007
• Issued: 02/26/2013
• Est. Priority Date: 08/28/2003
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Al-Ali, Ammar, Diab, Mohamed, Weber, Walter M.
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Assistant Examiner(s): Liu, Chu Chuan (JJ)
• Application Number:
  US11/834,602
• Publication Number:
  US 20080027294A1
• Time in Patent Office: 2,031 Days
• Field of Search: 600/309, 600/310, 600/322, 600/323, 600/324, 600/326, 600/330, 600/331, 600/336, 600/301
• US Class Current: 600/310
• CPC Class Codes: A61B 2560/0204 of power management
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• 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 5/72 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

Abstract

A physiological parameter tracking system has a reference parameter calculator configured to provide a reference parameter responsive to a physiological signal input. A physiological measurement output is a physiological parameter derived from the physiological signal input during a favorable condition and an estimate of the physiological parameter according to the reference parameter during an unfavorable condition.

Claims

1. A physiological parameter tracking system comprising:

a physiological signal input having at least first and second intensity signal components received from a light-sensitive detector that detects light of at least first and second wavelengths transmitted through body tissue carrying pulsing blood;

a first calculator configured to output a reference parameter responsive to the physiological signal;

a second calculator configured to output an ancillary parameter responsive to the physiological signal;

a third calculator configured to output a slow parameter that is a function of the reference parameter and the ancillary parameter and is slowly varying in time relative to the reference parameter and the ancillary parameter; and

a fourth calculator configured to output a physiological measurement responsive to the reference parameter and the slow parameter, wherein the fourth calculator provides a physiological measurement that is at least in part of a function of the reference parameter and the slow parameter and wherein the physiological measurement is a function of the reference parameter and the slow parameter during a first time interval and is the ancillary parameter during a second time interval.

2. The physiological parameter tracking system according to claim 1 wherein the first time interval includes a period when calculations of the ancillary parameter are unfavorable.

3. The physiological parameter tracking system according to claim 2 wherein the second time interval includes a period when calculations of the ancillary parameter are favorable.

4. A physiological parameter tracking system comprising:

a physiological signal input having at least first and second intensity signal components received from a light-sensitive detector that detects light of at least first and second wavelengths transmitted through body tissue carrying pulsing blood;

a reference parameter calculator configured to output a reference parameter responsive to the physiological signal;

means for outputting a physiological parameter derived from the physiological signal input during a favorable condition and estimating the physiological parameter according to the reference parameter during an unfavorable condition;

means for relating the reference parameter to the physiological parameter during the unfavorable condition; and

means for selecting a first time period for outputting the derived physiological parameter and a second time period for outputting the estimated physiological parameter.

5. A physiological parameter tracking system comprising:

a physiological signal input having at least first and second intensity signal components received from a light-sensitive detector that detects light of at least first and second wavelengths transmitted through body tissue carrying pulsing blood;

a reference parameter calculator configured to output a reference parameter responsive to the physiological signal;

a physiological measurement calculator configured to output a physiological parameter derived from the physiological signal input during a favorable condition and estimating the physiological parameter according to the reference parameter during an unfavorable condition;

a slow parameter calculator configured to relate the reference parameter to the physiological parameter during the unfavorable condition; and

an update processor configured to select a first time period for outputting the derived physiological parameter and a second time period for outputting the estimated physiological parameter.