Concentration measurement device and concentration measurement method

• US 9,700,248 B2
• Filed: 12/25/2012
• Issued: 07/11/2017
• Est. Priority Date: 02/20/2012
• Status: Active Grant

• Current Assignee: Hamamatsu Photonics KK
• Original Assignee: Hamamatsu Photonics KK
• Inventors: Ozaki, Takeo, Suzuki, Susumu
• Primary Examiner(s): Winakur, Eric
• Assistant Examiner(s): LIU, CHU CHUAN
• Application Number:
  US14/377,931
• Publication Number:
  US 20150045640A1
• Time in Patent Office: 1,659 Days
• Field of Search: 600310, 600322, 600323, 600326, 600328, 600333, 600340, 600473, 600476, 600483
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/6814 Head
• CPC Class Codes: G01N 2021/3144 for oxymetry
• CPC Class Codes: G01N 21/314 with comparison of measurements at specific and non-specific wavelengths dual wavelength spectrometry G01J3/427
• CPC Class Codes: G06F 17/17 Function evaluation by approximation methods, e.g. inter- or extrapolation, smoothing, least mean square method G06F17/18 takes precedence ; interpolation for numerical control G05B19/18

Abstract

A concentration measurement apparatus includes a probe, having a light incidence section making measurement light incident on the head and a light detection section detecting the measurement light that has propagated through the interior of the head, and a CPU determining temporal relative change amounts of oxygenated hemoglobin concentration and deoxygenated hemoglobin concentration and determining a correlation coefficient of the relative change amounts and a polarity of a slope of a regression line.

Claims

1. An apparatus for measuring temporal relative change amounts of oxygenated hemoglobin concentration and deoxygenated hemoglobin concentration, that vary due to repetition of chest compression, in a head, comprising:

a light source configured to output measurement light;

a light detector configured to detect the measurement light that has propagated through the interior of the head and generate a detection signal in accordance with the intensity of the detected measurement light; and

a processor that is electrically coupled to the light detector and programmed to;

determine, based on the detection signal, a first temporal relative change amount of the oxygenated hemoglobin concentration and a second temporal relative change amount of the deoxygenated hemoglobin concentration,

determine a magnitude of a correlation coefficient of the first and second temporal relative change amounts,

determine a polarity of a slope of a regression line of the first and second temporal relative change amounts, and

evaluate occurrence of reverse direction blood transmission from the vena cava to the head in the chest compression based on the magnitude of the correlation coefficient and the polarity of the slope of the regression line.

2. The apparatus according to claim 1, wherein the processor is programmed to further determine a temporal relative change amount of total hemoglobin concentration based on the first and second temporal relative change amounts, and

the apparatus further comprises a display configured to display the temporal relative change amount of the total hemoglobin concentration together with the magnitude of the correlation coefficient and the polarity of the slope of the regression line.

3. The apparatus according to claim 1, wherein the processor is programmed to further determine an oxygen saturation based on the first and second temporal relative change amounts, and

the apparatus further comprises a display configured to display the oxygen saturation together with the magnitude of the correlation coefficient and the polarity of the slope of the regression line.

4. The apparatus according to claim 2, wherein the display displays the magnitude of the correlation coefficient by at least one of a numeral and a graph.

6. The apparatus according to claim 3, wherein the display displays the magnitude of the correlation coefficient by at least one of a numeral and a graph.

5. A method of measuring temporal relative change amounts of oxygenated hemoglobin concentration and deoxygenated hemoglobin concentration, that vary due to repetition of chest compression, in a head, the method comprising:

fixing a probe including a light source and a light detector on the head;

making measurement light that is output from the light source incident on the head;

detecting the measurement light that has propagated through the interior of the head and generating a detection signal in accordance with the intensity of the detected measurement light by the light detector;

determining, by a processor that is electrically coupled to the light detector, based on the detection signal, a first temporal relative change amount of the oxygenated hemoglobin concentration and a second temporal relative change amount of the deoxygenated hemoglobin concentration;

determining, by the processor, a magnitude of a correlation coefficient of the first and second temporal relative change amounts;

determining, by the processor, a polarity of a slope of a regression line of the first and second temporal relative change amounts; and

evaluating, by the processor, occurrence of reverse direction blood transmission from the vena cava to the head in the chest compression based on the magnitude of the correlation coefficient and the polarity of the slope of the regression line.