CN1120427A - Woundless monitor for pulse rate blood oxygen saturation degree - Google Patents

Abstract

The pulse rate and blood-oxygen saturation degree monitor using spectrometry is composed of spectrum sensing probe, photoelectric driver, linear detector, computer for closed-loop control, precise stabilized DC power supply, display device, buzzer and keyboard and features high reliability, long service life, and high anti-interference performance and precision.

Description

Woundless monitor for pulse rate blood oxygen saturation degree

The present invention relates to a kind of pulse frequency, ohmeda 3700 pulse oxmeter, be particularly related to a kind of Woundless monitor for pulse rate blood oxygen saturation degree that adopts spectral measurement methods, belong to monitor class Medical Instruments, can not have wound ground, continuous real-time monitoring patient's pulse frequency and blood oxygen saturation.

Blood oxygen saturation, promptly HbO2 Oxyhemoglobin accounts for the percentage ratio of hemoglobin total amount in the human body artery blood, is the important physiological parameter of reflection tissue oxygen supply situation.Before noinvasive blood trouble oxygen saturation monitoring technology was used, the method for normally adopting and extract the human body artery blood sample, measuring the vim and vigour dividing potential drop was measured blood oxygen saturation.Its shortcoming is to monitor in real time, increases the painful and infection probability of patient.Since 1974, Britain, Japan, the U.S., Germany etc. begin the noinvasive blood trouble oxygen saturation monitor of development of practical in succession; At present external blood oxygen instrument enters the stage of applying, has realized no wound continuous real-time monitoring.The patented technology of disclosed this respect as U.S. Pat-3998550, US4446871, US4759369, US4824242, US5058588, reaches Japan Patent J03086152, European patent EP 104771, EP104772 etc.

The development of no wound pulse frequency blood oxygen instrument at present is two aspect trend:

(1) as the critical function module of comprehensive multiparameter clinical monitor, is used with other monitoring function.

(2) improve precision, reliability, anti-interference adaptability and miniaturization, to standing property miniature monitor development.

At present domesticly do not see a complete set of this quasi-instrument of development voluntarily as yet, only relate to the computer software and hardware of this quasi-instrument as the blood oxygen instrument of Ningxia computer center development in 1991.

More than the shortcoming of these instruments, be all not adopt the automatic regulatory function of light intensity of the direct closed loop control of computer, influenced sensing probe and different experimenters and sensing probe have been referred to press from both sides the adaptability of factors such as elasticity variation, the long-life and the reliability of luminescent device with accuracy of instrument; The coupling design of sensing probe photoelectric device is relatively poor, and precision is low, and volume is big, and in addition, signal deteching circuit and DC voltage-stabilizing current circuit design optimization are poor.

The objective of the invention is to adapt to various environmental disturbances and different experimenters, high accuracy, high reliability, volume Woundless monitor for pulse rate blood oxygen saturation degree little, easy to use for a kind of automatic regulatory function of light intensity that adopts the direct closed loop control of computer is provided.

The objective of the invention is to realize by following technical scheme.Get the spectrum sensing gauge head ready, the photoelectricity drive circuit, signal deteching circuit, computer, the precision DC regulated power supply, display device, buzzer, keyboard etc., the spectrum sensing gauge head is connected with the linearity test circuit with electric drive circuit by lead, the photoelectricity drive circuit is connected with computer by flat multi-conductor cable with the linearity test circuit, computer and display device, buzzer is connected with lead respectively with keyboard, the precision DC regulated power supply by lead respectively with the photoelectricity drive circuit, the linearity test circuit is connected with computer, promptly constitute Woundless monitor for pulse rate blood oxygen saturation degree, realized the automatic regulatory function of light intensity of the direct closed loop control of computer.

The spectrum sensing gauge head changes in order to responsive blood oxygen saturation and pulse, form by upper shell, light source assembly, lining, photelectric receiver, lower house and spring, light source assembly and photelectric receiver are fixed on the housing, are connected with the linearity test circuit with the photoelectricity drive circuit by lead; Light source assembly is made as integrated light-emitting assembly with protruding transmissive optical structure by two gallium aluminum arsenide high brightness light emitting diode tube cores and gallium arsenide light emitting diode tube core sintering;

Photoelectricity drive circuit and linearity test circuit are realized photoimpact timesharing modulation in order to drive spectrum sensing gauge head light source assembly, and impulse modulation and the demodulation of finishing useful signal detect; The photoelectricity drive circuit is made up of program control integrated operational amplifier CA3280 and peripheral circuit thereof, and is connected with the computer sequence circuit; The linearity test circuit is by preposition differential amplifier circuit, and HONGGUANG, infrared two sampling maintenances and low pass, high-pass filtering circuit and bias light signal deteching circuit are formed, and are connected with the computer sequence circuit;

Computer detects control and disturbs accident analysis in order to the closed loop of finishing instrument, finishes data acquisition, calculating and output; The structure of computer is to be main frame with the NCS800 chip, external EPROM 27C256, intervalometer 82C54, analog/digital converter ADC0848, digital/analog converter AD7528 and address latch 74HC373, decoder 74HC138,74HC541, each a slice of signal latch 74HC259 is formed;

The precision DC regulated power supply is in order to provide stable, the isolated DC voltage of digital simulation, totally three kinds ± 5.0V and+7.00V, many kinds of-2.5V, and monitor current changes automatically; The precision DC regulated power supply reasonably holds the sense buffer circuit by two-stage regulating and controlling voltage output circuit and collocation and forms;

Display device, buzzer and keyboard show observation process, test result, information and warning in order to input control order and data.

The invention provides a kind of conforming disturbs and pulse frequency ohmeda 3700 pulse oxmeter different experimenters, the high accuracy high reliability.Its major advantage is:

Realized that the sensing probe light intensity of microcomputer closed loop control regulates automatically, can control the experimenter automatically points and inserts before and after the sensing probe and different experimenter points luminous quantity when changing, can obviously improve sensing probe device lifetime and reliability, guarantee the instrument test precision not tested person person point the influence of factors such as the colour of skin, size and the variation of finger tip elasticity;

The development and design of the protruding type integrated light-emitting of the high brightness assembly of two kinds of specific wavelengths, light intensity coupling has guaranteed miniaturization, reliability and the precision stability of sensing probe;

Adopt the signal deteching circuit design of the omnidistance control of computer, realized the signal detection scheme and the test failure analysis of digit pulse modulation and demodulation, improved equipment anti-interference ability, guaranteed measuring accuracy and easy to useization;

The employing flat multi-conductor cable interconnects, and adopts the general method of tightening up to be installed in the plastic compression Instrument shell, and precision height of the present invention, reliability height, volume are little, easy to use; Can be widely used in clinical monitoring fields such as internal medicine, surgery, Anesthesia Department, emergency center.

Below in conjunction with accompanying drawing the present invention is described in further detail:

Fig. 1 is a structural representation of the present invention.

Fig. 2 is a computer control software block diagram of the present invention.

Fig. 3 is a sensing probe structural representation of the present invention.

Fig. 4 drives and signal deteching circuit figure for photoelectricity of the present invention.

Fig. 5 is a computer system circuit diagram of the present invention.

Fig. 6 is precision DC voltage-stabilized power supply circuit figure of the present invention.

Referring to figs. 1 through Fig. 6, get spectrumsensing gauge head 1 ready,photoelectricity drive circuit 2,linearity test circuit 3, computer 4,display device 5,buzzer 6,keyboard 7, precision DC regulatedpower supply 8, spectrumsensing gauge head 1 is connected with linearity test circuit 4 withelectric drive circuit 3 by lead,photoelectricity drive circuit 3 is connected with computer 4 by flat multi-conductor cable with linearity test circuit 4, computer 4 anddisplay device 5,buzzer 6 is connected with lead respectively withkeyboard 7, precision DC regulatedpower supply 8 by lead respectively withphotoelectricity drive circuit 2,linearity test circuit 3 is connected with computer 4, promptly constitutes Woundless monitor for pulse rate blood oxygen saturation degree.

The spectrum sensing gauge head changes in order to responsive blood oxygen saturation and pulsation, is made up of upper shell 31, light source assembly 32, lining 33, photelectric receiver 34, lower house 35 and spring 36; Light source assembly 32 and photelectric receiver 34 are fixed on the housing, and are connected withlinearity test circuit 3 withphotoelectricity drive circuit 2 by lead;

The light source assembly 32 of spectrum sensing gauge head by two gallium aluminum arsenides (AsAlGa) HONGGUANG (a high brightness light emitting diode tube core of 680nm wavelength, wave band≤10nm) and a GaAs (GaAs) infrared (the Light-Emitting Diode tube core of 960nm wavelength, wave band≤10nm), sintering is made as the integrated light-emitting assembly with protruding transmissive optical structure;

Photoelectricity drive circuit 2 andlinearity test circuit 3 are realized photoimpact timesharing modulation in order to drive spectrum sensing gauge head light source assembly, and impulse modulation and the demodulation of finishing useful signal detect;Photoelectricity drive circuit 2 is made up of program control integrated operational amplifier CA3280 and peripheral circuit thereof, finished by the timesharing pulse signal of computer 4 controls the timesharing pulse of luminescent device photoelectric current is supplied with, thereby the timesharing digit pulse that realizes photosignal is modulated; Photoelectric current intensity is carried out stepping control by computer 4DAC output signal;Linearity test circuit 3 is by preposition differential amplifier circuit, HONGGUANG, infrared two sampling maintenances and low pass, high-pass filtering circuit, form the digit pulse demodulation sequential after amplifying by this timesharing pulse-modulated signal of computer 4 sequence circuits control realization with the bias light signal deteching circuit:

Computer 4 detects control and disturbs accident analysis in order to the closed loop of finishing instrument, finishes data acquisition, calculating and output; Computer 4 is a main frame with the NCS800 chip, external EPROM27C256, intervalometer 82C54, analog/digital converter ADC0848, digital/analog converter AD7528, and address latch 74HC373, decoder 74HC138,74HC541, each a slice of signal latch 74HC259 is formed microsystem;

Precision DC regulatedpower supply 8 is in order to providing stable, the isolated DC voltage of digital simulation, and totally three kinds ± 5.0V and 7.00V, many kinds of-2.5V, and monitoring power supply changes automatically; The precision DC mu balanced circuit reasonably holds the sense buffer circuit by two-stage regulating and controlling voltage output circuit and collocation and forms.

Display device 5,buzzer 6 andkeyboard 7 are in order to input control order and data, show observation process, test result, announcement signal and warning.

The concrete work process of the present invention is as follows:

After the instrument start work, spectrumsensing gauge head 1 luminous intensity is higher, and computer 4 detects optical signal when too strong, adjusts luminous intensity, makes luminous deepening, guarantees the device long-life, controlsbuzzer 6 anddisplay device 5 prompting users simultaneously; After treating that the experimenter points insertion, instrument adopts the HONGGUANG of two kinds of narrow wave bands of specific wavelength and infrared light with 400～1000 times/second frequency, the pulsewidth of 1～10 μ s is alternately shone tissue, the light intensity of measuring different wave length through the photodetector of a wide response spectra changes, change with responsive its trap, and be converted to faint current signal; Computer 4 carries out the optical signal pulses modulation by the sequencing controcharging drive circuit 2 of timesharing pulse-modulated signal, controlslinear testing circuit 3 simultaneously and carries out pulse amplification demodulation, thereby obtain ratio S:

S=(V_RAC/ V_RDC)/(V_IRAC/ V_IRDC) V in the formula of (1) (1)_RACThe of ac that expression red light irradiation post-absorption degree changes, all the other are similar, and DC represents direct current, and AC represents to exchange, and R represents HONGGUANG, IR represents infrared light; This ratio is non-linear, but has good repeatability, and rule of thumb correction formula and data correction carry out linearization process.Pulse rate signal detects more or less freely, can adopt the detection method at zero point of general pulsation AC signal

When situations such as strong bias light interference of appearance and improper use, computer 4 can be judged according to the data of bias light comparison circuit and ADC collection, the prompting user.

Above work process and scheme have guaranteed HONGGUANG, the infrared electro signal strict symmetry in detection, and can effectively eliminate the influence of factors such as spectrumsensing gauge head 1 folder position, human body vibration, bias light interference, skin difference.

The present invention also takes following interference protection measure respectively: the precision DC regulated power supply of optimal design; Pick off and photoelectric device housing all adopt insulant, handle the housing ground wire well; Preferred high-quality multi beam shielding flexible circuit conductor, the useless frequency range of circuit at different levels is isolated mutually in the signal detection; Strict guarantee is quoted the isolation between power supply; When disturbing in the signal when big, design detects software and determines that the finger tip position is improper, ambient signal disturbs or equipment circuit self-interference three class situations, so that the experimenter uses and adjusts; Thereby guaranteed operate as normal and the measuring accuracy of instrument in various environmental conditions.

Claims (7)

1. Woundless monitor for pulse rate blood oxygen saturation degree, comprise buzzer [6], keyboard [7], display device [5], it is characterized in that described Woundless monitor for pulse rate blood oxygen saturation degree also comprises spectrum sensing gauge head [1], photoelectricity drive circuit [2], linearity test circuit [3], computer [4], precision DC regulated power supply; Spectrum sensing gauge head [1], by upper shell [31], light source assembly [32], lining [33], photelectric receiver [34], lower house [35] and spring [36] are formed, spectrum sensing gauge head [1] is connected with linearity test circuit [3] with photoelectricity drive circuit [2] by lead, photoelectricity drive circuit [2] is connected with computer [4] by flat multi-conductor cable with linearity test circuit [4], computer [4] and display device [5], buzzer [6] is connected with lead respectively with keyboard [7], precision DC regulated power supply [8] by lead respectively with photoelectricity drive circuit [2], linearity test circuit [3] is connected with computer [4].

2. Woundless monitor for pulse rate blood oxygen saturation degree as claimed in claim 1 is characterized in that described light source assembly [32] is made as integrated light-emitting assembly with protruding transmissive optical structure by two gallium aluminum arsenide high brightness light emitting diode tube cores and GaAs Light-Emitting Diode tube core sintering.

3. Woundless monitor for pulse rate blood oxygen saturation degree as claimed in claim 1 is characterized in that described photoelectricity drive circuit [2] is made up of program control integrated operational amplifier CA3280 and peripheral circuit thereof, and is connected with computer [4] sequence circuit.

4. Woundless monitor for pulse rate blood oxygen saturation degree as claimed in claim 1, it is characterized in that described linearity test circuit [3] is made up of preposition differential amplifier circuit, HONGGUANG, infrared two sampling maintenances and low pass, high-pass filtering circuit and bias light signal deteching circuit, and be connected with computer [4] sequence circuit.

5. Woundless monitor for pulse rate blood oxygen saturation degree as claimed in claim 1, it is characterized in that described computer [4] is is main frame with the NCS800 chip, external EPROM27C256, intervalometer 82C54, analog/digital converter ADC0848, digital/analog converter AD7528 and address latch 74HC373, decoder 74HC138,74HC541, each a slice of signal latch 74HC259 is formed.

6. Woundless monitor for pulse rate blood oxygen saturation degree as claimed in claim 1 is characterized in that described precision DC electric current of voltage regulation [8] reasonably holds the sense buffer circuit by two-stage regulating and controlling voltage output circuit and collocation and forms.

7. the described Woundless monitor for pulse rate blood oxygen saturation degree of claim 1 is characterized in that described spectrum sensing gauge head [1] adopts 5 core external shield flexible cable and plugs of 2 meters of length, is connected with the linearity test circuit with the photoelectricity drive circuit.

Images