CN202589509U - Blood pressure and blood oxygen saturation degree simultaneous detection device - Google Patents

Abstract

The utility model discloses a blood pressure and blood oxygen saturation degree simultaneous detection device, and belongs to the technical field of radial artery detection, in order to solve the problem that the existing detection of the blood pressure and blood oxygen saturation degree needs to be detected by individual sensors, thus electronic elements are multiple, and structures are complex. The device comprises a cuff, a pulse generator, a photoelectric volume sensor, a wave peak retainer, a first high-pass filter, a first low-pass filter, a second high-pass filter, a second low-pass filter, an A/D (analog to digital) converter, a D/A (digital to analog) converter, a calculator, an electric and air transformer, an air pump, a power amplifier and a pressure sensor; radial artery acts as the detection object, thus blood pressure, and the blood oxygen saturation degree of arterial blood and venous blood can be detected synchronously, and the indirect measurement on the blood oxygen saturation degree of the venous blood is realized. The blood pressure and blood oxygen saturation degree simultaneous detection device provided by the utility model is suitable for the synchronous detection of the blood pressure and blood oxygen saturation degree.

Description

Checkout gear in the time of blood pressure and blood oxygen saturation

Technical field

Checkout gear when this utility model relates to a kind of blood pressure and blood oxygen saturation belongs to Radial artery detection technique field.

Background technology

At present, the blood pressure indirect measurement method when clinical or daily health detection has multiple.For example, traditional is the mercury sphygmomanometer blood pressure measuring method based on the Ke Shi method of detected object with the upper arm brachial artery; Radial artery with the wrist place is the electric sphygmomanometer blood pressure measuring method based on the pressure oscillographic method of detected object, and based on the electric sphygmomanometer blood pressure measuring method of volume vibratory drilling method; With refer to tremulous pulse be detected object based on the electric sphygmomanometer blood pressure measuring method of volume vibratory drilling method etc.And for the indirect measurement method of blood oxygen saturation normally to refer to that tremulous pulse is a detected object, adopt the dual wave length spectrophotometry method to carry out the oxygen saturation measurement of arterial blood.When the method for stating was in the use measured blood pressure and blood oxygen saturation, the measurement of blood pressure needed independent sphygomanometer, and the measurement of blood oxygen saturation also needs independent blood oxygen saturation detector.Even if use multi-tester to measure blood pressure and blood oxygen saturation simultaneously, its inner measuring process still adopts independent photoelectric sensor to realize that both can not dual-purpose respectively.Like this, just caused the electronic component of checkout gear to reach complex structure and other problems more; Simultaneously, this method can not realize the indirect measurement to the blood oxygen saturation of venous blood.

Summary of the invention

This utility model is need adopt independent pick off to realize respectively for the detection that solves existing blood pressure and blood oxygen saturation, causes the electronic component of checkout gear to reach baroque problem, checkout gear when a kind of blood pressure and blood oxygen saturation are provided more.

Checkout gear in the time of said blood pressure of this utility model and blood oxygen saturation; It comprises cuff; It also comprises pulse generator, photoelectricity volume sensor, crest keeper, first high pass filter, first low pass filter, second high pass filter, second low pass filter, A/D converter, D/A converter, the mechanical, electrical space-variant parallel operation of calculating, air pump, power amplifier and pressure transducer

Air pump is the cuff air feed through pipeline; Electricity space-variant parallel operation is arranged on the pipeline between air pump and the cuff; The control signal input of electricity space-variant parallel operation connects the control signal output ends of power amplifier; The control signal input of power amplifier connects the analog signal output of D/A converter, and the digital signal input end of D/A converter connects the control signal output ends of computer;

The pressure acquisition end of pressure transducer is through the pipeline connection between pipeline and electric space-variant parallel operation and the cuff, and the pressure signal outfan of pressure transducer connects the pressure signal input of A/D converter;

The photoelectricity volume sensor is arranged in the cuff; The photoelectricity volume sensor is made up of the first wavelength light emitting diode, the second wavelength light emitting diode and photodiode; First pulse signal output end of pulse generator connects the pulse signal input terminal of the first wavelength light emitting diode; Second pulse signal output end of pulse generator connects the pulse signal input terminal of the second wavelength light emitting diode; The 3rd pulse signal output end of pulse generator connects first driving signal input of photodiode; The 4th pulse signal output end of pulse generator connects second driving signal input of photodiode; First pulse signal of pulse generator and the 3rd pulse signal conducting simultaneously or close; Second pulse signal and the 4th pulse signal of pulse generator are closed or conducting simultaneously; Photodiode is respectively applied for the photoelectricity plethysmogram signal of gathering the first wavelength light emitting diode and the second wavelength light emitting diode; The acquired signal outfan of photodiode connects the acquired signal input of crest keeper; The wavelength signals outfan corresponding to the first wavelength light emitting diode of crest keeper connects lightwave signal input and first low pass filter and the lightwave signal input of first high pass filter simultaneously, and the lightwave signal outfan of first high pass filter connects first input end of analog signal of A/D converter, and the lightwave signal outfan of first low pass filter connects second input end of analog signal of A/D converter; The wavelength signals outfan corresponding to the second wavelength light emitting diode of crest keeper connects lightwave signal input and second low pass filter and the lightwave signal input of second high pass filter simultaneously; The lightwave signal outfan of second high pass filter connects the 3rd input end of analog signal of A/D converter, and the lightwave signal outfan of second low pass filter connects the 4th input end of analog signal of A/D converter, and the digital signal output end of A/D converter connects the acquired signal input of computer.

The emission wavelength of the first wavelength light emitting diode is 940nm, and the emission wavelength of the second wavelength light emitting diode is 805nm, and the wavelength photoreceptor center range of photodiode is 805nm to 940nm.

The driving frequency of pulse generator is 500Hz.

First pulse signal of said pulse generator and the relation of second pulse signal are: in a cycle period of pulse generator pulse signal; The ON time of first pulse signal and second pulse signal respectively was 1/3 cycle, and first pulse signal and the second pulse signal alternate conduction or the time difference of closing were 1/6 cycle.

The utility model has the advantages that: this utility model is detected object with the Radial artery in use, can realize the blood oxygen saturation of blood pressure and artery and vein blood is detected simultaneously, and it has realized the indirect measurement to the blood oxygen saturation of venous blood.This utility model can use under the situation that blood oxygen saturation is low and the tip circulation is very poor, and the precision of detection is high, has realized the non-invasive detection of Svo2; Improved and detected stability; Simplify the structure, reduced cost, but and the miniaturization of implement device.

Description of drawings

Fig. 1 is the electrical principle block diagram of this utility model device;

Fig. 2 is the detection schematic diagram of this utility model;

Fig. 3 is the absorbance curve chart corresponding to Fig. 2;

Fig. 4 is reduced hemoglobin Hb and the HbO2 Oxyhemoglobin Hbo absorption curve figure to HONGGUANG and infrared light.

The specific embodiment

The specific embodiment one: this embodiment is described below in conjunction with Fig. 1; Checkout gear in the time of said blood pressure of this embodiment and blood oxygen saturation; It comprises cuff 1; It also comprises pulse generator 2; Photoelectricity volume sensor 3; Crest keeper 4; The first high pass filter 5-1; The first low pass filter 5-2; The second high pass filter 5-3; The second low pass filter 5-4; A/D converter 6; D/A converter 7; Computer 8; Electricity space-variant parallel operation 9; Air pump 10; Power amplifier 11 and pressure transducer 12

Air pump 10 is cuff 1 air feed through pipeline; On the pipeline that electricity space-variant parallel operation 9 is arranged between air pump 10 and the cuff 1; The control signal input of electricity space-variant parallel operation 9 connects the control signal output ends of power amplifier 11; The control signal input of power amplifier 11 connects the analog signal output of D/A converter 7, and the digital signal input end of D/A converter 7 connects the control signal output ends of computer 8;

The pressure acquisition end of pressure transducer 12 is through the pipeline connection between pipeline and electric space-variant parallel operation 9 and the cuff 1, and the pressure signal outfan of pressure transducer 12 connects the pressure signal input of A/D converter 6;

Photoelectricity volume sensor 3 is arranged in the cuff 1; Photoelectricity volume sensor 3 is made up of the first wavelength light emitting diode, the second wavelength light emitting diode and photodiode; First pulse signal output end of pulse generator 2 connects the pulse signal input terminal of the first wavelength light emitting diode; Second pulse signal output end of pulse generator 2 connects the pulse signal input terminal of the second wavelength light emitting diode; The 3rd pulse signal output end of pulse generator 2 connects first driving signal input of photodiode; The 4th pulse signal output end of pulse generator 2 connects second driving signal input of photodiode; First pulse signal of pulse generator 2 and the 3rd pulse signal conducting simultaneously or close; Second pulse signal and the 4th pulse signal of pulse generator 2 are closed or conducting simultaneously; Photodiode is respectively applied for the photoelectricity plethysmogram signal of gathering the first wavelength light emitting diode and the second wavelength light emitting diode; The acquired signal outfan of photodiode connects the acquired signal input of crest keeper 4; The wavelength signals outfan corresponding to the first wavelength light emitting diode of crest keeper 4 connects lightwave signal input and the first low pass filter 5-2 and the lightwave signal input of the first high pass filter 5-1 simultaneously; The lightwave signal outfan of the first high pass filter 5-1 connects first input end of analog signal of A/D converter 6; The lightwave signal outfan of the first low pass filter 5-2 connects second input end of analog signal of A/D converter 6, and the wavelength signals outfan corresponding to the second wavelength light emitting diode of crest keeper 4 connects lightwave signal input and the second low pass filter 5-4 and the lightwave signal input of the second high pass filter 5-3 simultaneously, and the lightwave signal outfan of the second high pass filter 5-3 connects the 3rd input end of analog signal of A/D converter 6; The lightwave signal outfan of the second low pass filter 5-4 connects the 4th input end of analog signal of A/D converter 6, and the digital signal output end of A/D converter 6 connects the acquired signal input of computer 8.

In this embodiment, be provided with power amplifier 11,, be difficult to control the action of electric space-variant parallel operation 9 because the command signal of D/A converter 7 outputs is generally less.Therefore; Between D/A converter 7 and electric space-variant parallel operation 9, power amplifier 11 is set; The voltage signal of output is carried out power amplification, reach electric space-variant parallel operation 9 actions of control, regulate the air capacity that gets into cuff, the purpose that the pressure in the cuff is risen with certain speed.

The specific embodiment two: this embodiment is further specifying embodiment one; The emission wavelength of the first wavelength light emitting diode is 940nm; The emission wavelength of the second wavelength light emitting diode is 805nm, and the wavelength photoreceptor center range of photodiode is 805nm to 940nm.

Photoelectricity volume sensor 3 is made up of LED and photodiode PD of two different wave lengths.Two wavelength LED can adopt integral structure as light source.Absorb the scope that its wavelength photoreceptor of catoptrical PD need cover 805nm and 940nm, promptly can effectively absorb the reflected light of two wavelength LED.

The specific embodiment three: this embodiment is for to the further specifying of embodiment one or two, and the driving frequency of pulse generator 2 is 500Hz.

The specific embodiment four: this embodiment is further specifying embodiment one, two or three; First pulse signal of said pulse generator 2 and the relation of second pulse signal are: in a cycle period of pulse generator 2 pulse signals; The ON time of first pulse signal and second pulse signal respectively was 1/3 cycle, and first pulse signal and the second pulse signal alternate conduction or the time difference of closing were 1/6 cycle.

The detection method blood pressure of checkout gear and blood oxygen saturation time the in the time of based on embodiment one said blood pressure and blood oxygen saturation, it may further comprise the steps:

Step 1: photoelectricity volume sensor 3 is arranged between the contact surface of cuff 1 inner surface and skin;

Step 2: regulate the air inflow that gets in the cuff 1 through regulating electric space-variant parallel operation 9, the pressure in the cuff 1 is risen, with the speed of 5mmHg/S until the pressure that reaches regulation;

Step 3: four pulse signals of clamp-pulse generator 2 output, when making first pulse signal and the conducting simultaneously of the 3rd pulse signal of pulse generator 2, second pulse signal and the 4th pulse signal are closed simultaneously; In the time of the conducting simultaneously of second pulse signal of pulse generator 2 and the 4th pulse signal; First pulse signal and the 3rd pulse signal are closed simultaneously; Realize driven the intermittence of two light emitting diodes; Photodiode is gathered the photoelectricity plethysmogram signal of corresponding light emitting diode when each light emitting diode is lighted respectively simultaneously;

Step 4: crest keeper 4 is exported the reflected light signal that photodiode detects two kinds of wavelength that obtain respectively according to the pulse logic of pulse generator 2; Handle by 8 pairs of all image data of computer, obtain the blood pressure and the blood oxygen saturation numerical value at position to be detected.

In this embodiment, in the cuff pressure regulating system of being made up of electric space-variant parallel operation 9 and air pump 10, air pump 10 is normal air feed, and how much what therefore get into air capacity in the cuff is to be confirmed by the size of electric space-variant parallel operation 9 adjustings self electromagnetic valve opening.Meanwhile, the pressure variation that air inflow is brought in the cuff detects through pressure transducer 12.

Authorized pressure described in the step 2 of this embodiment can be decided to be for general user on the normal pressure of user and add 30～50mmHg.

8 pairs of image data of computer are handled the method that obtains blood pressure values and are in the step 4: the lightwave signal that the second high pass filter 5-3 that obtains gathered A/D converter 6 by computer 8 calculates with the pressure signal employing volume vibratory drilling method that pressure transducer 12 is gathered in the cuff 1 that obtains; Obtain mean blood pressure and flexible numerical value of pressing, and calculate the numerical value of diastolic pressure.

Computational methods about blood pressure values: for a light emitting diode in the photoelectricity volume sensor 3, through detecting its photoelectricity volume PGac signal, or catoptrical variation delta I ^λSignal utilizes the volume vibratory drilling method to confirm the peak SBP and the meansigma methods MBP of indirect blood pressure

8 pairs of image data of computer are handled the method that obtains blood oxygen saturation numerical value and are in the step 4:

At first, when position to be detected does not receive cuff 1 compressing, its absorbance A ^{λ i}For:

$A^{\mathrm{\λi}}=\log (I_0^{{\mathrm{\λ}}_i}/I^{{\mathrm{\λ}}_i})=({\mathrm{\ϵ}}_{\mathrm{Hb}}^{{\mathrm{\λ}}_i}{C}_{\mathrm{Hb}}^a+{\mathrm{\ϵ}}_{\mathrm{Hbo}}^{{\mathrm{\λ}}_i}{C}_{\mathrm{Hbo}}^a)d_a+({\mathrm{\ϵ}}_{\mathrm{Hb}}^{{\mathrm{\λ}}_i}{C}_{\mathrm{Hb}}^v+{\mathrm{\ϵ}}_{\mathrm{Hbo}}^{{\mathrm{\λ}}_i}{C}_{\mathrm{Hbo}}^v)d_v+{\mathrm{\ϵ}}_t^{{\mathrm{\λ}}_i}{C}_t{d}_t+B^{{\mathrm{\λ}}_i},$

I ₀ ^{λ i}Be incident light quantity, I ^{λ i}Be reflection light quantity, λ i=λ 1, λ 2, and λ 1 is the lightwave signal corresponding to the first wavelength light emitting diode, and λ 2 is the lightwave signal corresponding to the second wavelength light emitting diode,

is the specific absorbance of reduced hemoglobin Hb

is the reduced hemoglobin Hb concentration of arterial blood; is the absorptivity of oxyhemoglobin Hbo

is the HbO2 Oxyhemoglobin Hbo concentration of arterial blood

d _aBe the optical path length of arterial blood,

Be the reduced hemoglobin Hb concentration of arterial blood,

Be the HbO2 Oxyhemoglobin Hbo concentration of arterial blood,

d _vBe the optical path length of venous blood,

Be the specific absorbance of muscular tissue, C _tBe the concentration of muscular tissue,

d _tBe the optical path length of muscular tissue,

Absorption for light at random;

Cuff 1 compressing that receives when position to be detected does not change arteries, when having only vein blood vessel to change, corresponding to the wavelength X 2 of the wavelength X 1 of the first wavelength light emitting diode and the second wavelength light emitting diode respectively at V ₁Absorbance under the state

With the absorbance under the V2 state With

Be respectively:

$A_{{\mathrm{<figure-callout\; id="1"\; label="v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">v</figure-callout>}}_1}^{{\mathrm{\&lambda;}}_1}=\log (I_0^{{\mathrm{\&lambda;}}_1}/I_{v_1}^{{\mathrm{\&lambda;}}_1})=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hb}}^a+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hbo}}^a)d_a+({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hb}}^v+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hbo}}^v)d_{v1}+{\mathrm{\&epsiv;}}_t^{{\mathrm{\&lambda;}}_1}{C}_t{d}_t+B^{{\mathrm{\&lambda;}}_1},$

${\mathrm{<figure-callout\; id="1"\; label="A\; v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">A</figure-callout>}}_{v_{}}^{{}_1}=\log (I_0^{{\mathrm{\&lambda;}}_2}/I_{v_1}^{{\mathrm{\&lambda;}}_2})=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hb}}^a+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hbo}}^a)d_a+({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hb}}^v+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hbo}}^v)d_{v1}+{\mathrm{\&epsiv;}}_t^{{\mathrm{\&lambda;}}_2}{C}_t{d}_t+B^{{\mathrm{\&lambda;}}_2},$

${\mathrm{<figure-callout\; id="2"\; label="A\; v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">A</figure-callout>}}_{v_{}}^{{}_2}=\log (I_0^{{\mathrm{\&lambda;}}_1}/I_{v_2}^{{\mathrm{\&lambda;}}_1})=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hb}}^a+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hbo}}^a)d_a+({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hb}}^v+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hbo}}^v)d_{v2}+{\mathrm{\&epsiv;}}_t^{{\mathrm{\&lambda;}}_1}{C}_t{d}_t+B^{{\mathrm{\&lambda;}}_1},$

${\mathrm{<figure-callout\; id="2"\; label="A\; v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">A</figure-callout>}}_{v_{}}^{{}_2}=\log (I_0^{{\mathrm{\&lambda;}}_2}/I_{v_2}^{{\mathrm{\&lambda;}}_2})=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hb}}^a+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hbo}}^a)d_a+({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hb}}^v+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hbo}}^v)d_{v2}+{\mathrm{\&epsiv;}}_t^{{\mathrm{\&lambda;}}_2}{C}_t{d}_t+B^{{\mathrm{\&lambda;}}_2},$

Because at v ₁, v ₂The blood under the state in the arteries and the absorbance of muscular tissue do not change, and supposition is constant from the absorption of light at random in the small interval of cuff pressurization, and then the absorbance of venous blood two wavelength light is poor

With

Be respectively:

$\mathrm{\&Delta;}{A}_{v_1-v_2}^{{\mathrm{\&lambda;}}_1}=A_{v_1}^{{\mathrm{\&lambda;}}_1}-A_{v_2}^{{\mathrm{\&lambda;}}_1}=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hb}}^v+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hbo}}^v)\mathrm{\&Delta;}{d}_{v_1-v_2},$

$\mathrm{\&Delta;}{A}_{v_1-v_2}^{{\mathrm{\&lambda;}}_2}=A_{v_1}^{{\mathrm{\&lambda;}}_2}-A_{v_2}^{{\mathrm{\&lambda;}}_2}=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hb}}^v+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hbo}}^v)\mathrm{\&Delta;}{d}_{v_1-v_2}\text{,}$

In the formula Be v ₁With v ₂The optical path difference of venous blood under the state,

Cuff 1 compressing that receives when position to be detected makes the artery and vein vascular locking; The extinction characteristic of muscular tissue and light at random is constant; Have only the light path of the blood in the arteries to change, suppose corresponding to the wavelength X 1 of the first wavelength light emitting diode and the wavelength X 2 of the second wavelength light emitting diode to be respectively a ₁And a ₂During state, the absorbance of arterial blood two wavelength light poor

With

Be respectively:

$\mathrm{\&Delta;}{A}_{a_1-{\mathrm{<figure-callout\; id="2"\; label="a"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">a</figure-callout>}}_2}^{{\mathrm{\&lambda;}}_1}=A_{a_1}^{{\mathrm{\&lambda;}}_1}-A_{a_2}^{{\mathrm{\&lambda;}}_1}=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hb}}^a+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}{C}_{\mathrm{Hbo}}^a)\mathrm{\&Delta;}{d}_{a_1-a_2},$

$\mathrm{\&Delta;}{A}_{a_1-{\mathrm{<figure-callout\; id="2"\; label="a"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">a</figure-callout>}}_2}^{{\mathrm{\&lambda;}}_2}=A_{a_1}^{{\mathrm{\&lambda;}}_2}-A_{a_2}^{{\mathrm{\&lambda;}}_2}=({\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hb}}^a+{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_2}{C}_{\mathrm{Hbo}}^a)\mathrm{\&Delta;}{d}_{a_1-a_2},$

Be a ₁And a ₂The optical path difference of arterial blood under the state,

Use SvO ₂The expression Svo2, SaO ₂The expression arterial oxygen saturation, then

${\mathrm{<figure-callout\; id="2"\; label="SvO"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">SvO</figure-callout>}}_2=C_{\mathrm{Hbo}}^v/(C_{\mathrm{Hbo}}^v+C_{\mathrm{Hb}}^v),$

${\mathrm{<figure-callout\; id="2"\; label="SaO"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">SaO</figure-callout>}}_2=C_{\mathrm{Hbo}}^a/(C_{\mathrm{Hbo}}^a+C_{\mathrm{Hb}}^a),$

Above-mentioned all formula are found the solution acquisition Svo2 SvO ₂With arterial oxygen saturation SaO ₂:

${\mathrm{<figure-callout\; id="2"\; label="SvO"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">SvO</figure-callout>}}_2=\frac{{\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}}{{\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}-{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}}-\frac{\mathrm{\&beta;}}{{\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}-{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}}\&times;\frac{\mathrm{\&Delta;}{A}_{v_1-{\mathrm{<figure-callout\; id="2"\; label="v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">v</figure-callout>}}_2}^{{\mathrm{\&lambda;}}_1}}{\mathrm{\&Delta;}{A}_{v_1-{\mathrm{<figure-callout\; id="2"\; label="v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">v</figure-callout>}}_2}^{{\mathrm{\&lambda;}}_2}},$

${\mathrm{<figure-callout\; id="2"\; label="SvO"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">SvO</figure-callout>}}_2=\frac{{\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}}{{\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}-{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}}-\frac{\mathrm{\&beta;}}{{\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}-{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}}\&times;\frac{\mathrm{\&Delta;}{A}_{a_1-a_2}^{{\mathrm{\&lambda;}}_1}}{\mathrm{\&Delta;}{A}_{a_1-a_2}^{{\mathrm{\&lambda;}}_2}},$

β is λ in the formula ₂The absorptance of reduced hemoglobin Hb and HbO2 Oxyhemoglobin Hbo when selective reduction Hb H b and HbO2 Oxyhemoglobin Hbo have the isobestic point wavelength.

In this utility model related moving,, Svo2 detects principle and is:

This utility model adopts two wavelength optical spectroscopies to carry out the arteriovenous blood oxygen saturation and detects; The different tissues of considering the human detection position is different to seeing through light or catoptrical absorbing state; Can be simplified to the optical absorption model that constitutes by muscular tissue, tremulous pulse and vein with detecting the position, as shown in Figure 2.When pressurizeing for the detection position through cuff 1, because muscular tissue is incompressible, promptly its thickness does not change in the pressure process, therefore can consider that the optical characteristics of muscular tissue is constant.And vein blood vessel and arteries managed inner volume and can constantly dwindle until locking under the effect of cuff pressure, brought the variation of extinction characteristic thus.At first, the pressure of vein blood vessel is low, and distortion is earlier consequently pressed off fully under sleeve effect with pressure; Then, arteries is pressurized gradually, so that arteries is pressed off fully.The change records of extinction characteristic in cuff 1 pressure process is got off, can find on the extinction characteristic curve, to exist because of quiet, arterial vascular mechanical characteristic difference has a flex point.That is, the former part of this flex point is the variation of the extinction characteristic of venous blood, and later part is the variation of the extinction characteristic of arterial blood.Like this, can flex point be boundary just, through extinction characteristic component separating quiet, arterial blood is come out.

In this embodiment when position to be detected does not receive cuff 1 compressing, its absorbance A ^{λ i}Preparation method obtain according to the Beer-Lambert law.Can know that by Fig. 2 and Fig. 3 press hour when cuff, arteries does not change, and has only vein blood vessel to change.Therefore its corresponding state is V ₁, V ₂Be pressurized to a shown in Fig. 3 when detecting the position ₁, a ₂During state, vein blood vessel is locking, and the supposition of the extinction characteristic of muscular tissue and light at random is constant, then has only the light path of the blood in the arteries to change.

Through Svo2 SvO ₂With arterial oxygen saturation SaO ₂Computing formula can also calculate blood O2 difference after the metabolism, that is:

$\mathrm{Sa}-\mathrm{<figure-callout\; id="2"\; label="v\; O"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">v</figure-callout>}{O}_{}{}_2=\frac{\mathrm{\&beta;}}{{\mathrm{\&epsiv;}}_{\mathrm{Hb}}^{{\mathrm{\&lambda;}}_1}-{\mathrm{\&epsiv;}}_{\mathrm{Hbo}}^{{\mathrm{\&lambda;}}_1}}\&times;(\frac{\mathrm{\&Delta;}{A}_{v_1-{\mathrm{<figure-callout\; id="2"\; label="v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">v</figure-callout>}}_2}^{{\mathrm{\&lambda;}}_1}}{\mathrm{\&Delta;}{A}_{v_1-{\mathrm{<figure-callout\; id="2"\; label="v"\; filenames="HDA00001811866500011.png,HDA00001811866500021.png"\; state="\{\{state\}\}">v</figure-callout>}}_2}^{{\mathrm{\&lambda;}}_2}}-\frac{\mathrm{\&Delta;}{A}_{a_1-a_2}^{{\mathrm{\&lambda;}}_1}}{\mathrm{\&Delta;}{A}_{a_1-a_2}^{{\mathrm{\&lambda;}}_2}}),$

Factor beta in the formula;

can obtain the absorption curve of HONGGUANG and infrared light through Hb shown in Figure 4 and Hbo; But consider the discreteness that photo-sensor properties is actual, also will confirm usually through the experiment calibration.

In this embodiment, through detecting the reflected light I of two LED ^λSignal, and relevant treatment such as take the logarithm calculates the artery and vein blood oxygen saturation.Two wavelength LED adopt pulsed drive, and driving frequency is chosen as 500Hz.In order to obtain each LED, two LED are carried out intermittently driving to detecting the absorbing state at position.That is, when a LED lighted, another LED extinguished, and vice versa.Corresponding with it, PD also is intermittent connectivity, detects the reflected light signal of two wavelength LED respectively, and keeps the loop to make detected signal become successive curve through sampling.Pressure signal in the pressurized cuff is that the pressure transducer of in one, adorning temperature-compensating and signal amplification detects, as the foundation of confirming the internal blood vessel blood pressure.Above-mentioned photosignal that detects and pressure signal are input in the computer through 16 A/D converters, and carry out processing, record and the storage of data here; Meanwhile, the control of cuff internal pressure is calculated and is also here carried out, and by assigning instruction to electric space-variant parallel operation 9 here, control gets into the air capacity of cuff, and the pressure in the cuff is risen with certain speed.

The isobestic point wavelength that said reduced hemoglobin Hb and HbO2 Oxyhemoglobin Hbo have is 805nm.

Claims (4)

1. checkout gear blood pressure and blood oxygen saturation the time; It comprises cuff (1); It is characterized in that: it also comprises pulse generator (2); Photoelectricity volume sensor (3); Crest keeper (4); First high pass filter (5-1); First low pass filter (5-2); Second high pass filter (5-3); Second low pass filter (5-4); A/D converter (6); D/A converter (7); Computer (8); Electricity space-variant parallel operation (9); Air pump (10); Power amplifier (11) and pressure transducer (12)

Air pump (10) is cuff (a 1) air feed through pipeline; Electricity space-variant parallel operation (9) is arranged on the pipeline between air pump (10) and the cuff (1); The control signal input of electricity space-variant parallel operation (9) connects the control signal output ends of power amplifier (11); The control signal input of power amplifier (11) connects the analog signal output of D/A converter (7), and the digital signal input end of D/A converter (7) connects the control signal output ends of computer (8);

The pressure acquisition end of pressure transducer (12) is through the pipeline connection between pipeline and electric space-variant parallel operation (9) and the cuff (1), and the pressure signal outfan of pressure transducer (12) connects the pressure signal input of A/D converter (6);

Photoelectricity volume sensor (3) is arranged in the cuff (1); Photoelectricity volume sensor (3) is made up of the first wavelength light emitting diode, the second wavelength light emitting diode and photodiode; First pulse signal output end of pulse generator (2) connects the pulse signal input terminal of the first wavelength light emitting diode; Second pulse signal output end of pulse generator (2) connects the pulse signal input terminal of the second wavelength light emitting diode; The 3rd pulse signal output end of pulse generator (2) connects first driving signal input of photodiode; The 4th pulse signal output end of pulse generator (2) connects second driving signal input of photodiode; First pulse signal of pulse generator (2) and the 3rd pulse signal conducting simultaneously or close; Second pulse signal and the 4th pulse signal of pulse generator (2) are closed or conducting simultaneously; Photodiode is respectively applied for the photoelectricity plethysmogram signal of gathering the first wavelength light emitting diode and the second wavelength light emitting diode; The acquired signal outfan of photodiode connects the acquired signal input of crest keeper (4); The wavelength signals outfan corresponding to the first wavelength light emitting diode of crest keeper (4) connects lightwave signal input and first low pass filter (5-2) and the lightwave signal input of first high pass filter (5-1) simultaneously; The lightwave signal outfan of first high pass filter (5-1) connects first input end of analog signal of A/D converter (6); The lightwave signal outfan of first low pass filter (5-2) connects second input end of analog signal of A/D converter (6); The wavelength signals outfan corresponding to the second wavelength light emitting diode of crest keeper (4) connects lightwave signal input and second low pass filter (5-4) and the lightwave signal input of second high pass filter (5-3) simultaneously; The lightwave signal outfan of second high pass filter (5-3) connects the 3rd input end of analog signal of A/D converter (6), and the lightwave signal outfan of second low pass filter (5-4) connects the 4th input end of analog signal of A/D converter (6), and the digital signal output end of A/D converter (6) connects the acquired signal input of computer (8).

2. checkout gear in the time of blood pressure according to claim 1 and blood oxygen saturation; It is characterized in that: the emission wavelength of the first wavelength light emitting diode is 940nm; The emission wavelength of the second wavelength light emitting diode is 805nm, and the wavelength photoreceptor center range of photodiode is 805nm to 940nm.

3. checkout gear in the time of blood pressure according to claim 1 and 2 and blood oxygen saturation is characterized in that: the driving frequency of pulse generator (2) is 500Hz.

4. checkout gear in the time of blood pressure according to claim 1 and 2 and blood oxygen saturation; It is characterized in that: first pulse signal of said pulse generator (2) and the relation of second pulse signal are: in a cycle period of pulse generator (2) pulse signal; The ON time of first pulse signal and second pulse signal respectively was 1/3 cycle, and first pulse signal and the second pulse signal alternate conduction or the time difference of closing were 1/6 cycle.

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