Improved electronic blood pressure detection method and device
Technical field the present invention relates to be used for the measurement blood pressure of diagnostic purpose, the method and apparatus of pulse frequency, relates in particular to a kind of method and apparatus of accurately suppressed zero pressure measxurement blood pressure.
Non-invasive blood pressure measuring method all is the oscillation method that adopts based on the cuff pulse wave in the background technology prior art.The non-invasive measurement method of human blood-pressure mainly contains auscultation (being called for short Ke Shi sound method) that utilizes the Ke Shi sound and the proportionality coefficient method (abbreviation succusion) of utilizing the cuff wave of oscillation.
Ke Shi sound method is that experienced medical personnel adopt stethoscope, mercury pressure is taken into account cuff, the charge/discharge gas capsule is by being bundled in cuff the appropriate location of experimenter's upper arm, press close to brachial artery with stethoscope, inflate increase pressure up to the blood flow of blocking arm with the charge/discharge gas capsule to cuff, progressively lower cuff pressure to recover the blood flow of arm by the charge/discharge gas capsule then, one of the artery blood flow of arm pulsation meeting generation is ascending in this process, the descending again Ke Shi change of tuneization, and can listen to the variation of Ke Shi sound to determine systolic pressure and diastolic pressure by stethoscope and mercury gauge.
Present most blood pressure measuring methods that have been to use based on succusion in electronic blood pressure measurement equipment, basic process and auscultation are very similar, promptly also boost to block the blood flow of arm by the cuff inflation, make the cuff deflation blood pressure lowering to recover the blood flow of arm then gradually, and the static pressure in the monitoring cuff and because of the pressure pulse wave that pulsation produced of arterial blood, but computational methods are by measuring pressure pulse wave and the corresponding cuff pressure thereof that artery blood flow pulsatile change at the deflation course arm is delivered in the cuff to be produced, can detect one group of amplitude from small to large, descending again pressure pulse involves corresponding descending cuff pressure, and be mean pressure with the corresponding cuff pressure of maximum of pressure pulse wave, come to press high direction to extrapolate systolic pressure according to the amplitude proportional coefficient of the pressure pulse wave of empirical value (maximum of pressure pulse wave multiply by two two pairing cuff pressure of range value that obtain less than 1 coefficient and is respectively systolic pressure and diastolic pressure) again, and extrapolate diastolic pressure (being called for short proportionality coefficient method) based on cuff vibration pulse magnitude to the direction that cuff forces down to cuff.
The basic structure of electronic blood pressure measurement equipment generally comprises pressure transducer and the treatment circuit that () detects cuff pressure; (2) the pressure pulse wave treatment circuit that changes based on cuff pressure; (3) excess pressure detecting sensor and amplification, protection treatment circuit; (4) gas circuit and the control of filling, exit that are connected with pressure transducer of cuff, control vent valve, inflator pump; (5) mould/number conversion, Single Chip Microcomputer (SCM) system, (six) power pack.Wherein the detection of pressure pulse wave and cuff pressure can be placed on venting stage or aeration phase after the inflation in the measuring process, the venting form in venting stage can be evenly to exit continuously (promptly to successively decrease with the 3-5mmHg uniform pressure, while detected pressures pulse wave), also can be that (promptly the step with 5-10mmHg lowers cuff pressure one by one in the step venting, detected pressures pulse wave on each pressure step), the big young pathbreaker of each step hypotension determines according to detected pulse wave amplitude.Continuously even venting form will increase the time of blood pressure measurement process, the influence that arm motion, position are changed also is difficult to overcome, its application is subjected to certain limitation, and step venting form will reduce the blood pressure measurement time, and can overcome because the interference of initiations such as arm motion, position variation, possesses better anti-jamming capability, so a lot of company adopts step venting form mostly in blood pressure measurement.
The shortcoming of prior art:
What the oscillation method that non-invasive blood pressure is measured realized relying on hardware and software comprehensively finishes blood pressure measurement; wherein hardware components considers that mainly one is the amplification to cuff pressure and pressure pulse wave signal; the 2nd, cuff is pressed independently overvoltage crowbar of another road; the 3rd, the digital circuit part, the present hardware components major defect of understanding has:
The detection of A, band pressure needs periodic school Z-operation, at present be automatic zero adjustment under the direct condition that does not have to inflate at cuff mostly, but because circuit drift exists and be difficult in blood pressure measurement process repeatedly guarantee that static pressure in the cuff can be reduced to the force value near " zero ", this will cause one to be to fail in possible school zero; The 2nd, school zero success but still may produce the force value deviation that causes because of zero migration can influence the accuracy that cuff pressure is measured in a word.
B, according to safe requirement, need to have two in the blood pressure measurement process and overlap the restriction that timing system is independently guaranteed Measuring Time, present blood pressure measurement module normally module self has a cover timing system, and provide an interface to trigger port to link to each other with the outside timing that provides, realize another set of independent timing system by the timing function of host computer, also can finish the safety requirements of independent timing, but this blood pressure module is not realized complete safe independence timing system, need the cooperation of host computer, will bring hidden danger to the Secure Application of blood pressure module like this.
Summary of the invention technical problem to be solved by this invention is to propose a kind of improved electronic blood pressure detection method and device for fear of the deficiencies in the prior art part.This method and apparatus is added three-way magnetic valve between cuff and pressure transducer, normal open QI KOU of this valve is connected with cuff by prolonging trachea, its normally closed QI KOU communicates with air, so just realized when carrying out blood pressure measurement, pressure transducer and whole gas circuit UNICOM, respond to the pressure in the gas circuit in real time, also make regularly and can carry out in the blood pressure measurement process and the interval of blood pressure measurement at every turn, by the switching that powers up to this three-way valve, make that above-mentioned pressure transducer can be directly and ambient atmosphere UNICOM, can obtain " zero pressure " calibration value exactly, realize the calibration automatically regularly of " zero pressure " of the no inner air path participation that cuff pressure is measured, finish the accurate measurement of cuff pressure.
Simultaneously, newly-increased one tunnel independence timing circuit, by a slice single-chip microcomputer or two fix 180 seconds ± 5 seconds time limit timer circuit composes in series, the input of this trigger is connected with an I/O mouth of the master microprocessor of blood pressure module (MCU), wherein when coming the starting impulse of autonomous MCU for one, start this timer work of prescribing a time limit, when receiving a termination pulse once more, will stop above-mentioned timer work in limited time, at its input a delay gate circuit is arranged in addition, prevent from when powering on, to produce trigger impulse and start fixed cycle operator unusually.
The present invention solve the technical problem by realizing by the following technical solutions:
Implement a kind of improved electronic blood pressure detection method, the system based on comprising that cuff, inflator pump, pressure transducer, pressure-releasing electromagnetic valve, master microprocessor, display screen, communication interface and host computer constitute is characterized in that described method comprises step:
A. at first, between cuff and pressure transducer, add three-way magnetic valve;
B. after, when system's energising is started working, make electromagnetic valve work in pressure transducer earlier and connect atmospheric state, pressure transducer carries out zero point correction and detects;
C. after zero point correction finishes, make electromagnetic valve work in the state that pressure transducer is connected cuff, when carrying out blood pressure measurement, starting inflator pump begins to pressurize to cuff, host computer receives data by communication interface and shows the cuff internal pressure or show the cuff internal pressure by display screen, after the cuff internal pressure reached setting value, gas replenishment process stopped;
D. system's opening/closing pressure-releasing electromagnetic valve according to the speed venting of setting, and detects whether the pulse signal appearance is arranged;
E. having detected pulse signal occurs; Master microprocessor carries out date processing according to the determined algorithm of solidification software, and shows the pressure value that records on display screen or host computer;
F. in measuring process, run into overtime or the overvoltage phenomenon, system opens pressure-releasing electromagnetic valve immediately, closes inflator pump, and cuff pressure is released, and guarantees safe in utilizationly, and master microprocessor is resetted again;
G. after the one-shot measurement normal termination, open pressure-releasing electromagnetic valve, cuff pressure is released, close pressure-releasing electromagnetic valve;
When h. carrying out blood pressure measurement once more, begin circulation, and regularly begin circulation from step b from step c.
Said method step a is described to be added three-way magnetic valve and comprises step between cuff and pressure transducer:
A. the public blow vent with three-way magnetic valve connects pressure transducer, and the normal open QI KOU connects cuff, and normally closed QI KOU is communicated with atmosphere;
B., the three-way valve drive circuit is set, and this circuit is controlled by master microprocessor;
C. master microprocessor the pin of three-way valve drive circuit control by output high level and low level, is made that electromagnetic valve works in public blow vent and normal open QI KOU path, the A condition of blocking with normally closed QI KOU and public blow vent and normally closed QI KOU path, and the B state of normal open QI KOU obstruction.
In the described measuring process of step f, run into overtime or the overvoltage phenomenon, system closes inflator pump immediately, opens pressure-releasing electromagnetic valve, be that an independent timing circuit is set in system, described independent timing circuit is started by master microprocessor control, timing time is closed inflator pump immediately, is opened pressure-releasing electromagnetic valve, with pressure releasing once to exporting a control signal to the overtime control circuit of overvoltage.
The present invention can also further implement by following technical scheme:
Manufacture and design a kind of improved electronic blood pressure checkout gear, comprise cuff, inflator pump, pressure transducer, pressure-releasing electromagnetic valve, master microprocessor, display screen and communication interface, especially also comprise three-way magnetic valve, described three-way magnetic valve is connected between cuff and the pressure transducer.
Described pressure-releasing electromagnetic valve connects valve-driving circuit, the input termination master microprocessor of described valve-driving circuit and the overtime control circuit of overvoltage, the output of an input termination independence timing circuit of the overtime control circuit of described overvoltage.
The startup timing input termination master microprocessor of described independent timing circuit.
The public blow vent of described three-way magnetic valve connects pressure transducer, and the normal open QI KOU connects cuff, and normally closed QI KOU is communicated with atmosphere.
Described independent timing circuit is that the master constitutes by second microprocessor, and realizes regularly, triggers function by software mode; An I/O interface of described second microprocessor connects an I/O interface of master microprocessor, and another I/O interface of second microprocessor connects an input of the overtime control circuit of overvoltage.
Described communication interface can be the RS232 interface, can also adopt USB interface.
The present invention compares with the circuit design of prior art, and first advantage is: optimized the gas circuit syndeton, realize cuff pressure automatically, the automatic calibration of the no gas circuit residual pressure influence in " zero-pressure force " accurately, increase the accuracy that cuff pressure is measured.
Second advantage is: adopted a cover timing circuit to realize independent time limit timing function in the blood pressure measurement process, really realized the regularly independent of module level, strengthened the blood pressure measurement process safe and guaranteed.
Description of drawings Fig. 1 is the principle of compositionality block diagram of the method for the invention and device;
Fig. 2, Fig. 3, Fig. 4 are the flow charts of the method for the invention;
Fig. 5 is the electrical schematic diagram of independent timing circuit in the device of the present invention.
The specific embodiment is further described in detail the present invention below in conjunction with accompanying drawing and most preferred embodiment.
Implement a kind of improved electronic blood pressure detection method, as shown in Figure 1: based on the system that comprises that cuff 10, inflator pump 50, pressure transducer 30, pressure-releasing electromagnetic valve 70, master microprocessor 100, display screen 110, communication interface 120 and host computer 200 constitute, as Fig. 2, Fig. 3, shown in Figure 4, described method comprises step:
A. at first, between cuff 10 and pressure transducer 30, add three-way magnetic valve 20;
B. after, when system's energising is started working, make electromagnetic valve 20 work in pressure transducer 30 earlier and connect atmospheric state, pressure transducer 30 carries out zero point correction and detects;
C. after zero point correction finishes, make electromagnetic valve 20 work in the state that pressure transducer 30 is connected cuff 10, when carrying out blood pressure measurement, starting inflator pump 50 starts working to cuff 10 pressurizations, host computer 200 receives data and shows cuff 10 internal pressures by communication interface 120, or by display screen 110 demonstration cufves 10 internal pressures, after cuff 10 internal pressures reached setting value, pressurization stopped;
D. system's opening/closing pressure-releasing electromagnetic valve 70 according to the speed venting of setting, and detects whether the pulse signal appearance is arranged;
E. having detected pulse signal occurs; Master microprocessor 100 carries out date processing according to the determined algorithm of solidification software, and is showing the pressure value that records on the display screen 110 or on the host computer 200;
F. in measuring process, run into overtime or the overvoltage phenomenon, system closes inflator pump 50 immediately, opens pressure-releasing electromagnetic valve 70, and cuff 10 internal pressures are released, and guarantees safe in utilizationly, and makes master microprocessor 100 reset again;
G. one-shot measurement finishes, and opens pressure-releasing electromagnetic valve 70, with pressure releasing, closes pressure-releasing electromagnetic valve 70;
When h. carrying out blood pressure measurement once more, begin circulation, and regularly begin circulation from step b from step c.
Said method step a is described to be added three-way magnetic valve 20 and comprises step between cuff 10 and pressure transducer 30:
A. the public blow vent with three-way magnetic valve 20 connects pressure transducer 30, and the normal open QI KOU connects cuff 10, and normally closed QI KOU is communicated with atmosphere;
B., three-way valve drive circuit 21 is set, and this circuit 21 is by master microprocessor 100 controls;
C. the pin of 100 pairs of three-way valve drive circuits of master microprocessor 21 control is by output high level and low level, make electromagnetic valve 20 work in public blow vent is communicated with the normal open QI KOU, with the A condition of normally closed gas disconnection and with public blow vent and the disconnection of normal open QI KOU, the B state that is communicated with normally closed gas.
As shown in Figure 1: in the described measuring process of step f, run into overtime or the overvoltage phenomenon, system closes inflator pump 50 immediately, opening pressure-releasing electromagnetic valve 70, is that an independent timing circuit 45 is set in system, and described independent timing circuit 45 is started by master microprocessor 100 controls, timing time is once arriving the overtime control circuit 46 of overvoltage to exporting a control signal, this circuit 46 is closed inflator pump 50 immediately, opens pressure-releasing electromagnetic valve 70, with pressure releasing.
A kind of improved electronic blood pressure checkout gear that manufactures and designs according to the method for the invention, as shown in Figure 1: comprise cuff 10, inflator pump 50, pressure transducer 30, pressure-releasing electromagnetic valve 70, microprocessor 100, display screen 110, communication interface 120 and host computer 200, especially: also comprise three-way magnetic valve 20, described three-way magnetic valve 20 is connected between cuff 10 and the pressure transducer 30.
Described pressure-releasing electromagnetic valve 70 connects valve-driving circuit 71, the input termination master microprocessor 100 of described valve-driving circuit 71 and the overtime control circuit 46 of overvoltage, the output of an input termination independence timing circuit 45 of the overtime control circuit 46 of described overvoltage.
The public blow vent of described three-way magnetic valve 20 connects pressure transducer 30, and the normal open QI KOU connects cuff 10, and normally closed QI KOU is communicated with atmosphere.
Described independent timing circuit 45 is that the master constitutes by the second microprocessor U2, and realizes regularly, triggers function by software mode; The I/O interface of the second microprocessor U2 connects an I/O interface of master microprocessor 100, and another I/O interface of the second microprocessor U2 connects an input of the overtime control circuit 46 of overvoltage.
Described communication interface 120 adopts the RS232 interface in most preferred embodiment, can also select USB interface for use in other embodiments.
Most preferred embodiment as shown in Figure 5: the P02 interface of the startup timing input termination master microprocessor 100 of described independent timing circuit 45.The second microprocessor U2 among the figure is made of the MSP430 type single-chip microcomputer of TI, finishes timing by the systems soft ware of MSP430, when U2 detects the startup timer signal, promptly starts software timer; When U2 detects termination timing device signal, promptly stop software timer; The restriction of this software timer will depend on the application model setting: promptly adult/neonate pattern is provided with, and adult mode is 180 ± 1 seconds, and the neonate pattern is 90 ± 1 seconds.
Certain above-mentioned timer can also adopt analog device to realize same function.
In this most preferred embodiment, the I/O mouth P1.0 of microprocessor U2 connects the input of overtime control circuit 46, when system is in other armed state except that the measurement state, this port keeps low level, and this port will be exported a high level when system is in normal surveying work state, and keep until this measuring process finishes, this port is got back to low level once more and is continued to keep armed state.When an input end of overtime control circuit 46 during in low level, timer is in and stops time status, have only that this port just has output when the timing of timer surpasses in limited time (as 180 ± 1 seconds (adult) or 90 ± 1 seconds (neonate)), start pressure-releasing electromagnetic valve 70, stop inflator pump 50, and notice master microprocessor 100.
Facts have proved that the present invention has optimized the gas circuit syndeton, realize cuff pressure automatically, " zero-pressure force " calibration automatically of no residual pressure influence accurately, increased the accuracy that cuff pressure is measured.
Simultaneously, the present invention has adopted a cover timing circuit to realize independent time limit timing function in the blood pressure measurement process, has really realized the regularly independent of module level, has strengthened the blood pressure measurement process safe and has guaranteed.