CN1625368A

CN1625368A - Passive physiological monitoring (P2M) system

Info

Publication number: CN1625368A
Application number: CNA028288653A
Authority: CN
Inventors: P·K·沙利文; K·C·K·张; C·J·沙利文; P·伯南布哥怀斯
Original assignee: HEINA MEDICAL CORP
Current assignee: HEINA MEDICAL CORP
Priority date: 2002-03-25
Filing date: 2002-03-25
Publication date: 2005-06-08
Anticipated expiration: 2022-03-25
Also published as: JP4344247B2; JP2006504443A; WO2003082111A1; AU2002311781A1; CN100518638C; EP1494586A4; EP1494586A1; CA2479972A1; HK1075190A1; AU2002311781B2

Abstract

Passive physiological monitoring apparatus has a sensor for sensing physiological phenomenon and method converter converts sensed data into electrical signals and a computer receives and computes the signals and output computed data for real-time interactive display. The sensor is a piezoelectric film of polyvinylidene fluoride. Signals detected include mechanical, thermal and acoustic signatures reflecting cardiac output, cardiac function, internal bleeding, respiratory, pulse, apnea and temperature. The sensor may be an array provided in a MEDEVAC litter or other device for measuring acoustic and hydraulic signals from the body of a patient for field monitoring, hospital monitoring, transport monitoring, home, remote monitoring.

Description

Passive type physiological moniyoting (P2M) system

Background technology

After the soldier sustains damage, reduce that as far as possible its time that is transported to the MCO of appropriate level is very important, can guarantee that so sick and wounded soldier gets timely medical treatment, and in time treatment is most important for sick and wounded soldier's survival.During this period, the aeromedical care in the dustoff environment usually is used for identifying and transporting the wounded.

No matter be wartime or peacetime, carry out daily aviation medicine by military unit and escort (aeromedical evacuations) that it is exposed under noise or ambient pressure and the abominable guard condition patient and flight/healthcare givers.With the same in common people community, the nurse of army provides accurate patient monitoring according to reliable and effective surveillance equipment under various environment, wherein has some to monitor that to using tradition instrument has hostility and crudity.Although it is lifesaving processes that aviation medicine is escorted for majority, medical worker's monitoring vital signs under high-noise environment almost is impossible.

Generally speaking, the supervision of vital signs only is one a simple conventional program, comprises the collection of pulse, breathing and blood pressure data.In a quiet relatively environment, these parameters can be measured easily.Yet, because several reasons makes that gathering the physiological signal of being concerned about in the helicopter environment is a challenging problem.Restriction on vital signs is collected comprises high noisy, vibration, audition interference, invalid surveillance equipment, narrow working condition, the bulky equipment during the air convoy and and electromagnetic interference aircraft system caused by some armarium.The other complexity of lead-in wire and electrode mixes with noise and environmental problem again.The physiological parameter of vital signs is in the frequency range that this helicopter produced.On these frequencies, the helicopter frequency has bigger power equally.A vibration harmony scholar also is bigger problem for factor.Therefore, this signal to noise ratio problem must use the alternate manner except low pass and high-pass filtering method to solve.Because the restriction of working condition, the medical worker can not use stethoscope accurately to monitor cardiomotility or blood pressure.

Army's medical system needs portable, non-invasive apparatus, and this equipment can monitor by the vital signs to the soldier in the battlefield environment under owing ecotopia.This system need for example escort in situation, the aviation medicine of mass casualties useful the medical worker of army of whole nursing dispensing scope, in ground ambulance transport, hospital's monitoring and the unit of providing special care to.Discover recently, with aviation armarium failure at least one secondary environment test of 32 percent of rotary wind type air ambulance flight.

Quartz crystal is a kind ofly can produce the mineral that electric field has piezoelectric effect when exerting pressure.The material scholar has been found that other material with piezoelectric property.The multifunctionality of piezoelectric and potential use are known, but expense is too high sometimes.

Yet the up-to-date decline on manufacturing cost now allows engineer and research worker that bigger application is arranged.The superior quality of piezoelectric has been applied to medical science, safety, acoustics, national defence, geology and other fields.The exploitation of applying piezoelectric material also is in the initial stage.

Medical practice and research based on piezo-electric apparatus are used just in the ascendant.Piezoelectric approach has been successfully used to plethysmography, utilized the blood pressure monitor of piezoelectricity contact microphone, the heart rate of the fry/bird of birds embryo and artificial incubation is monitored and various piezo-electric probe.The detector that piezoelectric uses the motion of opposing to carry out sensing moves, is used for the zooperal respiratory movement of nuclear magnetic resonance, NMR (NMR) with the vibration of measuring the people, the little animal body of response pharmacology operation.Combine with ultrasound wave, piezoelectric approach has been used to assess blood dynamics characteristic coronarius, elasticity tensor, endarterial image and receptor scope size (receptor field dimension).In addition, piezoelectric transducer has been attached to chest wall and has used with automatic auscultation equipment and the microcomputer that is used for the lung sound analysis.Piezoelectric film (piezoelectric film) is employed and studies, to measure joint contact pressure, the qualitative supervision that the while piezoceramic disk has been used to write down flesh sound and neuromuscular piece.

The random fluctuation theory is generally used for analyzing phenomenon pseudoperiod in the ocean engineering, but also can use it for the spectral peak that shows breathing and heart rate.People's heart beating, breathing and blood pressure are actually multiple, and it has reflected complicated mechanical-acoustics incident.Yet the variety of issue of piezo-electric apparatus exploitation stops its round Realization.The measurement of people's vibration only could be carried out when this environment is quiet utterly smoothly.In fact, in most hospital room, usually exist such as equipment, fan, people speak and patient self sound outside noise.Those noises have been covered the signal of being concerned about and have been made its distortion, have therefore limited the practicality of piezo-electric apparatus.In experimental animal models research, the animal noise makes data collection be difficult to carry out.Under non-lab environment, because its inherent signal-noise problem, the medical applications that is used for the piezo-electric apparatus of human body still has problems.

The nurse's of army a main task is to guarantee that sick and wounded soldier is nursed and/or escort specified MCO timely.In time period in the battlefield between the injured and wounded transhipment, carrying out suitable Medical Treatment action is crucial for the welfare of food for powder, and may be that life and death is not.Diagnosis and treatment begin and escort (for example passing through dustoff) when taking place during be material time.

Regrettably, inherent king-sized noise and vibration make nurse and medical worker can not accurately measure vital signs in the helicopter environment.Be not only the electron medical treatment monitor owing to judder becomes invalid; And the traditional method of utilizing stethoscope pulse and blood pressure also becomes unreliable under high noisy.Narrow working condition during aloft escorting and bulky equipment make these problem extensions.

Most of traditional methods adopt such equipment, these equipment use electrode, lead-in wire, electric wire and jacket (wrapped cuff) to measure one or more vital signss, and these equipment for example are sphygomanometer, ECG (electrocardiogram) monitor, pulse oximeter.Existing monitor needs some adnexaes, is not passive type or passive (passive) therefore.In addition, legacy equipment is extremely sensitive to noise, for example the noise of the electromotor of helicopter or aircraft and impeller etc.

Obviously, this common situation all needs such monitor, and wherein during the medical treatment that high noisy and vibration are arranged is escorted, this monitor can be all the time and accurately measured vital signs.Monitor is autonomous relatively, and nurse or technical staff's intervention is not necessary.Along with the telemetry that is used for telemonitoring and communication has more ability, information can be delivered to medical worker and other nursing staff positions in real time via radio communication.

Need exploitation to be used for the better method and the equipment of physiological moniyoting at present.

Summary of the invention

The present invention is called as passive type physiological moniyoting, P ²M or P2M simply.Have measured, the record of data record of bulk information (for example blood pressure), and can be depicted as subsequently, to determine the condition of surveilled subject.

In the latest development of material science and date processing for to utilize the new surveillance equipment of piezoelectric film, electroactive fluoropolymer to create probability.Although the medical application of piezoelectric film still is in the junior stage, the test of armarium is promising.

Utilization is called as the basis of the engineering phenomenon of " water hammer " as the work model of data analysis in blood pressure calculates, and this cardiovascular system is modeled as piping, pump and other adnexaes.

" water hammer " blocked suddenly when family's water, passes family's upper and lower conduit road network that pipeline and valve constitute and the compressional wave of propagating.The result can cause the damage of a tangible sound and upper and lower conduit road system.Unexpected velocity variations can cause the increase of pipeline pressure, thereby water hammer occurs, produces after water is blocked during valve closing usually.Being described below of this compressional wave:

c＝(1/ρ)*(dP/dV) (1)

Wherein c=compresses wave propagation velocity (ft/sec);

Variation (the V of dV=on speed _Initial-V _Final);

ρ=fluid density; And

DP=pressure changes.

Skalak (1966) develops a kind of theory with the linearized theory of viscous flow, can be used for understanding the main wave character in tremulous pulse and the vein.Vascular system is equal to the network of non-homogeneous transfer conduit.

Before the theory of Skala, Womersly (1957) is used in those principles on the single homogeneous tube of expression artery segment, and the result is compared with the test data that extracts on Canis familiaris L..Tested flow and from tested barometric gradient, calculate flow between have good concordance.

Anliker (1968) shows that the dispersion phenomenon relevant with endovascular ripple propagation is the potential standard of measurement of blood vessel and other cardiac parameters distribution (distubility).Anliker supposition blood vessel is worked as the Thin-Wall Cylindrical Shells that is full of the non-sticky compressible fluid.Model provides good concordance more completely.

Karr (1982) research is about the pressure wave speed of human body and develop a kind of method of definite pulse spread speed.This invention recognizes that this information may be used for determining that platelet is assembled on arterial wall, cholesterol gathers and arterial wall thickness.

Formula (1) can be according to pulse wave velocity (c) and flowing velocity (the definite pressure variation (dP) from heart pulse rate of the dispersion relation v).The method of Karr is measured flowing velocity, to determine and systolic pressure (pS) and the relevant dP of diastolic pressure (pD).

This new invention is according to heart beating and breathe common gaging pressure energy.Can determine the influence of heart by removing the influence of breathing in the energy spectrum to energy spectrum.By the result of calculation of speed energy spectrum and the velocity measurement of utilizing electromagnetism and Doppler method to obtain are compared, can leach the breathing energy.Because sympatheticotonia (sympathetic tone) can influence the accuracy of blood pressure measurement, therefore new monitor can be designed to, one in its piezoelectric transducer is used as special-purpose doppler sensor, and this doppler sensor utilizes supersonics to adjust the data interpretation relevant with patient's sympatheticotonia.The selectivity of P2M signal omit and the P2M sensing data with from the selectivity ratios of other partial data of body, the energy affect of heart is separated in and the comparison between the pick offs of two or more triggerings simultaneously.The P2M energy spectrum of determining from foot is different from the energy spectrum that draws from chest, and it provides the method when foot's power spectrum isolating cardiac energy during basically not from the energy of breathing.

In case (v) known, the relation between contraction and diastolic pressure (2) and Bernoulli equation (3) is used to measure blood pressure to speed.Bernoulli equation is hydromechanical fundamental relation formula, and this relational expression derives from Newtonian mechanics and law of conservation of energy.Can derive the more form of compression of same equation, flow to reflect more complicated instability.

p＝pD+(1/3)*(pS+pD) (2)

Wherein

The pS=systolic pressure;

The pD=diastolic pressure; And

The p=average pressure.

p＝ρgh+(1/2)*p*V ² (3)

Wherein

ρ=fluid density,

The g=gravity constant, and

The h=height, main energy term (head energy term).

From these formula, we can derive the expression formula of pD and pS, these two be pulse wave velocity (c), flowing velocity (v) with the function of pulse wave pressure (dP):

pD＝(1/2)*ρ*v ²-ρ*C*dV (4)

pS＝pD+ρ*C*dV (5)

P2M is very suitable in including but not limited to following situation several zones and comes the paramedical personnel:

(1) vital signs to severely injured personnel carries out medical monitoring under the strong noise of for example rescue helicopters and vibration environment, is to bother very much or impossible at the current surveillance technology of this occasion;

(2) monitor the wounded that cause owing to for example major disasters such as aircraft accident, earthquake and flood;

(3) physiological moniyoting by adopting on-the-spot easily " the clever stretcher " that uses of medical worker that a large amount of patients are carried out;

(4) monitor at the sick bed of leaving the military hospital that continues under patient's situation alone; And

(5) patient monitoring when postponing to handle owing to the temporary transient overload of armarium.

The exploitation of P2M or passive sensor array (multisensor syste) are great innovations in passive type monitors.By using the grid of passive sensor, reduce noise, from bio signal, to identify noise from the coherent signal of different liners (pad).This is very important under high-noise environment.In addition, the importance of passive type multisensor syste is that it provides the chance of monitored patient more all sidedly.As a kind of instrument, the passive sensor grid provides the method for innovation to come monitored patient under the hostile environment condition.This system provides a kind of like this instrument, utilizes this instrument, can measure except blood pressure, heart rate and the various parameters breathing.Inter alia, these parameters including, but not limited to, patient moving and sleep habit, the pulse intensity on the body different piece, relative blood flow amount and cardiac output.

This passive type physiology (P ²M) critical piece of system be passive sensor, the hardware, wave filter, data-collection and the signal-analysis software that are used to amplify.In a preferred embodiment, this single passive sensor is of a size of 8 " * 10 ", preferably is enclosed in the protective cover.Lead-in wire from this pick off is connected on the electronic machine (amplifier, wave filter, data-capture card, desk computer), wherein the original analog voltage signal is filtered and amplifies, and be converted to digital form.Then, carry out the digital filtering and the software operation of data with the frequency analysis form.At last, utilize signal processing technology to come from this digital signal, to extract physiologic information.

Preferably, transducer gasket is located immediately at below patient's back of lying on the back on Ambulance stretcher.Machinery/the acoustical signal that is produced by cardio-pulmonary function is sent to passive sensor via body, and this passive sensor becomes aanalogvoltage to conversion of signals.Figure 6 illustrates the example of existing P2M device.In the main hardware that is used to laboratory equlpment be: the charge amplifier of desk computer, multifunction programable and around support with the packing all hardware encapsulation frame (roll-around rack).In order to keep the multifunctionality of original research and exploitation, most of equipment are selected to improve functional to sacrifice space efficiency.

An object of the present invention is provides cheap, nonrestrictive, portable, light-duty, accurate and reliable device for military medical bodies, this equipment can be used on scene or the fixation means, being provided under high noisy and the vibration environment accurate measurement, escort and the medical treatment and nursing of hospital in disposing thereby improve in mass casualties situation, aviation medicine to heart rate, breathing and blood pressure.

An object of the present invention is the conditioning signal noise, in dual-use medical environment, to allow utilizing piezo-electric apparatus in rescue transportation, hospital bed monitoring and other application scenarios the patient.

An object of the present invention is in different site environments, to utilize piezoelectric film to develop experimental physiological moniyoting instrument.The variation of accuracy, accuracy, user personality and patient's comfort level has determined to collect the value of the field instrumentation of relevant vital signs data.

An object of the present invention is to provide or not under the patient adopts the situation of electrical lead or lead on one's body, monitor the means of the non-intrusion type of vital functions.Determine heart rate, breathing and blood pressure by acoustics and the electromagnetic signal of utilizing human body.

In the disclosure, these of invention and further and other purpose and feature be significantly, wherein the disclosure comprises top and description that writing, and claims and accompanying drawing.

Description of drawings

Fig. 1 is the sketch map of P2M system unit.

Fig. 2 is the perspective view of P2M system.

Fig. 3 is the graphical comparison of P2M bench run result and people's assessment of the measurement result.

Fig. 4 is the panel screen of this P2M system in drainage pattern and the front view of user interface.

Fig. 5 is the front view of the panel screen of this P2M system in the monitoring pattern.

Fig. 6 is the sketch map of this P2M pick off preferred embodiment.

Fig. 7 shows a graphic user interface (GUI) of this P2M system.

Fig. 8 shows the graphic user interface of this P2M system, and it has just shown the time series and the frequency domain representation of physiological data.

Fig. 9 shows the measurement of pulse wave passing time (PWTT).

Figure 10 there is shown system test and assessment result at a width of cloth.

Figure 11 is high noisy and the vibration test at Wheeler military airfield (Wheeler Army Air Field).

Figure 12 shows the measurement through flak jackets.

Figure 13 shows the test through flak jackets and military definite protective posture protector (MOPP gear) combination.

Figure 14 shows the sketch map that merges to passive type physiological moniyoting instrument (P2M) system that utilizes passive sensor array and microelectronic component in the Ambulance stretcher.

The specific embodiment

This preferred P2M system is the monitoring arrangement that has two main subsystems, and one of them is used for measuring-signal, and another is used for date processing is become significant information.

Fig. 1 shows the sketch map of this system, and Fig. 2 shows the perspective view of this system.At first, this piezoelectric film, a kind of electroactive fluoropolymer is converting the voltage measuring value that can support techniques of teime series analysis to as the mechanical energy by the caused motion of heart beating.Then, utilize microcomputer control system record and analyze this voltage, the reason of doing like this is to come signal and be presented on the screen or printout to it from the background noise difference.Technology such as the amplification in advance of using high pass and low pass filter and adjusting in advance has reduced noise.

The piezoelectric 1 that adopts is polymer poly vinylidene (PVDF), and this polymer can be configured as cable, thin film or thick tile.The PVDF piezoelectric film in environment be blocky, in light weight, soft, inherently firm, durable, repair and can excessive or disassembled for transport easily.Because this material is inert, therefore can in human body, use.Ultraviolet radiation harmlessly passes the pvdf membrane made from different-thickness.In addition, this piezoelectric film is a waterproof, can be operated between 0 to 145 degree centigrade, and can not tear under stress.PVDF can convert temperature reading to electricity output.This pvdf membrane is incorporated in the vinyl pad of fill fluid, and surface area is approximately 10cm * 10cm.This pad be positioned at the patient on/following/top diverse location place.

P2M measures heart and respiratory movement, and monitor pulse, breathing and time-out respiration case 3.Heart and the respiratory movement selective filter by primary signal is record simultaneously.This piezoelectric element 1 is a pressure sensing detector, and this detector is as the highly sensitive deformeter that the HDR and the linearity are provided.Analogue signal is sent to amplifier (x200-x5000) 5 via band filter and visually shows.Utilize the multichannel converter 7 that surpasses the 5kHz sampling frequency, will simulate acoustic signal and become digital value.Utilize fast Fourier transform (FFT), data transaction is arrived frequency domain.This system utilizes microcomputer 9 to write down, analyze and represents data, can carry out the online evaluation of data and judgement in real time like this.

In its shirtsleeve operation pattern, PVDF piezoelectric film 1 is as piezoelectric strain gauge.The output of this voltage reaches four orders of magnitude, and this is the output height that amplifying signal did not produce in the circuit that uses of self-resistance lead mode recently.The linearity and frequency response are all fine.Although similar,, therefore do not need to apply electric current because this device is self power generation with existing deformeter.Different with this deformeter is that the present invention does not produce with the unlimited electric charge that increases of sustained stress.The slowest frequency that this polymeric film is measured is a kilosecond to occur for an electric incident, and is up to a gigahertz (microwave).This piezoelectric film is a passive type, and is safe biologically, and this needs traditional deformeter of impressed current opposite with those.

The PVDF plate is the finished product of producing in batches (COTS), and its type and specification are selected according to optimum sensitivity scope and elasticity.Each plate comprises seven feet additional mask twisted-pair feeders (being used for noise suppressed) lead-in wire 11, to transmit the electric charge that this plate is produced.

Piezoelectric board 1 be positioned at patient's chest and foot below, perhaps in the same distant place of body, but on one's body perhaps jacket equally is placed on.Make this piezoelectric film produce voltage by patient respiratory and the variation of heart beating applied pressure, this voltage transmits by a radio-frequency filter 13 via no magnetic micro coaxial cable 11.This signal is sent to high input impedance amplifier 5 and the computer system 7 that is used for date processing then.Traditional oscillograph and chart recorder show this output.Then, breathing and heart rate 15 calculate by the energy spectrum from this time series data.

Several technology can reduce noise and vibration interference.Initiatively cut down (Active Cancellation) and adopt two piezoelectric transducers, one of them does not contact with body.That pick off that does not invest on the body is exposed in environmental acoustics and the vibration signal, and the pick off that invests simultaneously on the body is exposed in environment and the body signal.From an output, deduct another output and can obtain the body signal be concerned about.

Another preferably reduces the noise technology and comprises band filter/band elimination filter.By identification external electrical or acoustic noise and special frequency thereof, band leads to or band elimination filter is removed external signal from resultant signal.

In addition, utilize the signal processing technology of the existing knowledge of desired signal that desired information is extracted from this piezoelectric signal.Spectrum technology help to discern be concerned about the frequency and the amplitude of incident, and they are distinguished out from external noise.

The logical frequency limit of the band of 0.1-4.0Hz is adopted in the cardiomotility analysis, and breast rail adopts the frequency limit from 0.01-3.0Hz.The heart and the breath signal that are filtered are supplied with recording system.Can analyze somatic movement by the bandpass filtering that primary signal is carried out the 0.1-20Hz frequency limit.

In case the signal that is produced by thin film sensor becomes voltage and is exaggerated and filtering, is then handled by the P2M instrument.This hardware device including, but not limited to, can handle 586 processor computer 9 that having of mass data strengthens RAM and disk size.Patch panel (board) with audiorange is convenient to carry out data acquisition, Signal Pretreatment and signal processing.

For system operation, mastery routine 17 data acquisition/control, signal processing/analysis and data show/user interface three independently software module combine.LabVIEW is all used in all three subprograms ^TM" G " graphical programming language.Analog voltage signal is digitized and analyzes on time domain and frequency domain.The program that is used for Signal Pretreatment and analysis and develops comprises digital filtering, spectrum analysis, self correlation and noise suppression program.Data all can show in monitoring mode or acquisition mode in real time.When carrying out the new data renewal, the monitoring pattern shows that current data also abandons old reading, and drainage pattern preserves data to be used for later analysis.In drainage pattern, data volume can not surpass the hard disc storage capacity of computer.

As shown in Figure 2, transport in order to protect and to be convenient to, whole P2M system 19 packs in the rack 21 of a smithcraft, and this rack has castor (not shown) and locking glass door (not shown).This equipment further comprises the Ambulance stretcher 23 that pick off has been installed.Do not need patient's attachment device on the stretcher thereby this device can merge to, perhaps can be miniaturized and be the portable field equipment in the pocket with radio communication device.

For availability and the accuracy of verifying the P2M system, carried out effectively on the spot and analytical test.Piezoelectric film measurement mechanical signal, thermal signal and acoustic signal.In order non-invasively to measure life signal, high sensitivity is essential.For pulse rate, the physics of heart is beated and is delivered to the pressure film transducer gasket as mechanical pulsing by body.Measure breathing by the mechanical pulsing that is delivered on the pick off based on chest exercise.Responsive pressure film transducer gasket is measured all external movement and voice, forms the voltage signal output that is superimposed upon on the physiological signal.As a result, motion or the voice that formed by main body can cause error in reading.

Under this measurement environment, the physical impact that the P2M sensor measurement is all, electromagnetism (EM) noise that comprises patient's physiological signal, human-made noise on every side and active signal, sends from the noise of machine and vibration and lamp and instrument.Although output signal has comprised these all signals, majority is all very faint, can not impact measurement, yet other noise such as the EM noise but can destroy reading.By wave filter and other signal processing algorithms signal is handled and to be removed this noise.Then, by program preprocessed signal is analyzed, this program comprises the fast Fourier transform (FFT) of identification primary signal frequency.For a patient quietness, speechless, basic frequency is normally breathed, and second highest frequency is a heart rate.Patient body position and frequency harmonics can make this difference complicated, need extra logic to separate and discern the frequency peak of heart and breathing.This logical algorithm must be enough strong, so that can determine the peak value of breathing and heart under various conditions.

In order to improve resolution, select the data point of a large amount of high sampling rates, and to resample than low rate, to simplify the calculating of Accurate Analysis.This minimum sampling interval is 30 seconds.

Fig. 3 shows the measurement result of utilizing 20 breathing/pulse raties that the P2M system carries out.As a kind of contrast, also carried out the measurement of artificial assessment (human evaluator) simultaneously.Under ideal conditions, P2M accurately measures pulse 25 and breathes 27, but patient's motion or voice can disturb accurate measurement.The heart rate measurement quality does not reduce owing to lacking to breathe, and P2M is to mate less than the dancing error of per minute and this measurement of comparison result 29,31 simultaneously.

Fig. 4 shows the panel of the P2M that is in drainage pattern.Upper curve Figure 33 has shown 30 seconds windows of the time-sequence measuring of all physiological signals.In the curve Figure 33 of top (time series), the heart beating spiking has been shown, and corresponding to the low frequency SIN function of breath signal.Lower curve Figure 35 has illustrated same data in frequency domain.This first and maximum sharpness signal 37 corresponding to about 16.4 breathing/per minutes.This contrast groups 31 is measured 17 ± 2 breathing/per minutes.The breathing that shows by a relatively large margin of this spike is the maximum impulse of measuring by transducer gasket.Second largest spike 39 is per minute 60 times, and this is consistent with the measured actual heart rate of the sandwich rate monitor of finger tip.The energy of measuring by this amplitude is less than being present in 1/3rd of energy in this respiratory frequency, and this ratio is along with the position of patient's physiology and transducer gasket and change.Less spiking 41 representatives in lower graph are breathed and the heart rate harmonic wave, and the result of this harmonic wave is not ideal SIN function.Because heart rate may be to descend with the identical frequency of breathing harmonic wave, so be necessary to check harmonic wave with logical algorithm.This heart rate and breathing harmonic wave can compare by the signal of obtaining in the body different piece to be distinguished.

Button on the panel of interface program and menu 43 can be controlled data collection and analysis programme.Can store 30 seconds data record, be used to file or other assessment.

Fig. 5 shows the P2M system under monitoring mode.Upper curve Figure 45 shows time series data, and it has the typical high frequency heart beating spiking 47 that is superimposed upon on the low frequency respiratory wave 49.Middle part curve Figure 51 shows per five seconds and upgrades heart rate 53 once and breathe 55.When obtaining new five seconds serial datas, five seconds the oldest data are dropped, and have 30 seconds serial datas of new data simultaneously by analysis, recomputate heart rate and breathing.Upper curve 53 is red, the expression heart rate; Lower curve 55 is blue, and expression is breathed.Stable in the performance of middle 50s scope center rate, in middle tens seconds, breathing is arranged.Measurement with artificial control successfully compares the two (2).Anomalistic point 57 after 25 times are upgraded is attributable to patient moving or outside and indefinite noise/vibration incident.Lower curve Figure 59 shows the fast Fourier transform of time series signal.The regular voltage signal of heart beating provides the strength signal as the level relevant with blood pressure.The time between the signal of body different parts or the pattern of secondary singal provide the information of circulation or the obstruction or the interference of relevant blood flow.

In a further advantageous embodiment, Fig. 6 represents to have the sketch map of the P2M system that is positioned at patient 63 single passive sensor 61 on one's body.Fig. 7 shows a graphic user interface (GUI) of P2M system.Upper curve Figure 65 shows 30 seconds windows of digital voltage data, and wherein low-frequency oscillation is caused by breathing, and the altofrequency spike is that the patient on the stretcher is carried out the result that heart beating is measured.This time series signal is converted to frequency data by Fourier transformation, and is shown as a kind of energy spectrum, in the curve Figure 67 of middle part.According to these data, can be by energy check relevant with basic frequency 69 be obtained P﹠R.

In the method for optimizing of blood pressure measurement, can utilize the pulsation wave analysis to carry out the passive measurement of blood pressure (systolic pressure and diastolic pressure).The measurement and the characterization of pulse wave velocity (PWV), perhaps on the other hand, pulse wave passing time (PWTT) needs more than one measuring position inherently.Therefore, need a plurality of pick offs to measure at diverse location.For example, pick off can be measured the pulse wave characteristic along brachial artery, can carry out together with other measurement described herein.

Fig. 8 shows in the pulses measure result along two positions of arm.Time between two

corresponding peaks

71,73 is separated the pulse wave propagate time (PWTT) that provided.Systolic pressure that this value can be used for being correlated with and diastolic pressure.Similarly, must calibrate simultaneously for several measurements of PWTT and blood pressure, to set up calibration curve.Barschdorff ﹠amp; The pass that Erig shows between blood pressure (systolic pressure and diastolic pressure) and PWV and the PWTT is tied to form approximate linear.

The test and the assessment of P2M system have been carried out at TAMC in February, 1998.Measure when utilizing P2M, a kind of electronic machine monitor and artificial assessment to carry out P﹠R.Fig. 9 shows a width of cloth picture of testing at TAMC.Altogether 11 volunteers are monitored according to the test procedure of this pilot project.

Figure 10 has shown the result of this test.Compare with traditional method, the degree of accuracy of P2M surpasses 95%, and P2M and the inconsistent several situations of traditional method are proved to be very valuable in modification subsequently in the software of native system and the improvement simultaneously.In addition, utilize P2M, electronic machine monitor and artificial assessment, 12 voluntary nurses have carried out the physiological moniyoting of P﹠R.After this supervision was carried out, the nurse had finished comparison and the classification investigation of using above-mentioned three kinds of methods.

On March 5th, 1999,, carry out under high noisy and vibration environment, being used for the P2M system test of P﹠R at the Wheeler military airfield.During dustoff stand display (staticdisplay), test.The main purpose of test is to utilize P2M, microphone and accelerometer to high noisy/vibration environment characterization.The result shows, by filtering and signal analysis, this P2M can be from by distinguishing physiological signal caused high amplitude of helicopter and the frequency noise, accurately to export P﹠R.Because this high-noise environment can make traditional method invalid, so do not carry out traditional method in this test.

Figure 11 show on March 5th, 1999 in the P2M of Wheeler military airfield high noisy and vibration test.

Subsequently, at the Wheeler test period on March 5th, 1999,, also tested the ability of P2M system through multilamellar clothes and accurate monitor pulse of protector and breathing in order to reply the investigation of aviation flying physician.Utilize the P2M system that fragmentation protective body armor, military definite protective posture protector and the two combination are tested.The result shows to have between main body and the pick off under the situation of extra play, and the P2M test accuracy is still higher, and this effectively transmits by these solid layers mainly due to the contact area that increases and machinery and acoustic signal.

The verified single-sensor P that accurately measures P﹠R ²The M structure is very sensitive to patient position with respect to the master reference liner.The physiological signal quality and the size that receive by this system depend on the position.Preferred optimum position is that pick off directly is positioned at below patient's chest center.If this pick off is removed from this position, if perhaps this patient body position changes, then the globality of this input signal also changes.Like this, preferred configuration is to utilize a plurality of pick offs with the pattern that covers the whole zone of stretcher, and the patient lies in wherein, so that no matter patient moving still is static, all has one or more activity sensors to be in best measuring position all the time.

In a preferred embodiment, the present invention is a kind of passive type system that utilizes a distribution type pick off (perhaps " multisensor "), and wherein these pick offs can be accurately and monitored some physiological signal of human body lustily.Subsequently, can handle, be used for determining the vital signs of nurse and the current use of other nursing stafves, for example heart rate, breathing and systolic pressure/diastolic pressure these signals.

The passive type of parameter monitors and is in the scope of the invention such as cardiac output, cardiac function and internal hemorrhage.The present invention provides a kind of passive type (complete Noninvasive), inconspicuous and a kind of autonomous formula equipment especially; Promptly this equipment never disturbs patient's activity, does not also disturb other surveillance equipments, can enough minimum technological know-hows operate simultaneously.In addition, this equipment can high-noise environment and other make substitute and situation that existing method is invalid under operation reliably.These environment include but not limited to, the rescue (MEDEVAC) by helicopter or ambulance and see through military definite protective posture (MOPP) protector and operation that flak jackets carries out.

This abominable and the development of the reliable multi-sensor surveillance system of noise operation is arranged along with being used for, in the ICU of hospital (intensive care ward) environment, noise is less basically, and application herein is simpler.Even under the noiselessness environment, utilize the unware sensing system of patient, carry out complete non-intrusion type, passive type, pulse, breathing, blood pressure (bleed, suffer a shock or the like with detection, the inside of cardiac output) are measured has important inherent value.The passive type of this system and the operation of autonomous formula are applicable to that telemetry and real time remote monitor, the last feature of the present invention simultaneously is exactly to be used for long-range and remote measurement design feature supervisory control.

Figure 14 shows the sketch map of incorporating the P2M that utilizes passive sensor array and microelectronic component in the Ambulance stretcher into.The sketch map of incorporating creative technology in the Ambulance stretcher into has been shown among Figure 14 below.This stretcher 75 contains in the array 77 with 32 pick offs, and wherein each pick off is all measured acoustics and the hydraulic pressure input from patient 63.Each all comprises the signal of physiology ground generation and the measurement result of environmental noise in these signals.Environmental noise on each liner is similar, and that the signal that physiology ground produces is the position is relevant.This information can be used to isolate signal by inspection technology from noise.

The physiological signal that the position is relevant is used to judge that patient body position, heart rate, breathing, blood pressure, pulse intensity distribute and the measurement of more potential cardiac outputs.

Except Ambulance stretcher, the present invention also can incorporate in a lot of application.The operation that on the conventional mattress of hospital bed or employing at home the passive sensor array is configured is not too many to be changed.What specify is the Premature Infant Nursing zone.In this case, sensor lead is fixed on the baby normally very difficult, and the entanglement that can cause responsive skin to be upset and to go between.This pick off can be incorporated in the equipment that adopts in the civil and military department.This pick off also can be incorporated in field apparatus, clothes and the military uniform.This includes, but are not limited to, cervical region collar, flak jackets, biology and/or chemical hazard protective garment, extraction element (extractiondevice), clothes, the pad on seat and backrest.Exercise equipment such as stationary bicycle, treadmill or walking device can have benefited from pick off is attached on the support.

Physical signs such as heart rate can be measured by handle, and this helps to regulate exercise state.Other effective application can comprise the passive sensor system be used in psychometric chair or the bed on.The supervision of the physiological signs of main body can provide the indication that triggers words or the caused anxious state of mind of incident during the discussion.Do not needing under many test situation, can adjust the configuration of number of sensors and this sensor array in the size of each pick off, the array, full of foot specific needs and situation.For example, for mattress, 32 or more a plurality of pick off that can be in a rectangular array.

Preferred passive sensor can adopt piezoelectric film and pottery, hydrophone, microphone or pressure transducer.Amplify hardware and can comprise signal amplification circuit and the hardware such as charge amplifier.This system's Usage data collection hardware and signal processing hardware (circuit) and software.For the connection between pick off and the patient, can adopt solid, fluidised (air) or fluidic layer, example gel, water, foam, rubber, plastics or the like.This is connected with the transmission that helps physiological signal.

The present invention has huge medical value, can be used for field monitor, hospital's supervision, transports supervision and family/telemonitoring.For example, the present invention can be applied to every family carries out the passive type supervision to the patient hospital.The present invention is subtle for the patient, and this has increased the comfort level of monitoring process.

Although invention has been described with reference to specific embodiment, can make various modifications and variations of the present invention under the scope of the invention situation not breaking away from.

Claims

1. one kind is used for the equipment of monitor patient physiological passively, and described equipment comprises:

At least two pick offs, each described pick off comprises a piezoelectric film, is used for detecting from patient's physiological signal with from the ambient signal of patient's surrounding;

With the transducer that described at least two pick offs communicate, be used for described physiology and ambient signal are converted to digital signal;

With the processor that described transducer is communicated by letter, be used for from described digital signal, isolating the physiology digital signal, so that physiological data to be provided by the described digital signal between more described at least two pick offs; And

With the monitor of described processor communication, be used for showing in real time described physiological data.

2. equipment according to claim 1, wherein said piezoelectric film comprise Kynoar (PVDF) film.

3. equipment according to claim 1 further comprises at least one band filter that is connected with described at least two pick offs, is used for leaching at least one of described ambient signal.

4. equipment according to claim 3 further comprises a preamplifier that is connected with described band filter, and at least one that is used for described physiology and ambient signal carried out preposition amplification.

5. equipment according to claim 1, wherein said physiology and ambient signal are selected from comprise machinery, heat and the group of acoustic signal.

6. equipment according to claim 1, wherein said physiology and ambient signal show cardiac output, cardiac function, internal hemorrhage, breathing, pulse, asphyxia, body temperature signal and combination thereof.

7. equipment according to claim 2 further comprises the liner of having incorporated described polyvinylidene fluoride film into.

8. equipment according to claim 7, wherein said liner are the fluidic contact surfaces of filling that is used to promote the physiological signal transmission.

9. equipment according to claim 8, wherein said fluid are the inert matters of selecting from the group that comprises gel, water, air, foam, rubber and plastics or its combination.

10. equipment according to claim 1, wherein said processor further comprises the frequency Fourier transformation, is used for described physiology digital signal is converted to frequency data.

11. equipment according to claim 10 further comprises the microcomputer that is used to write down, analyze and show described frequency data, so that described frequency data are carried out online evaluation, simultaneously described frequency data is carried out real-time response.

12. equipment according to claim 1, wherein said piezoelectric film are placed in diverse location place under the patient.

13. equipment according to claim 1, wherein said piezoelectric film places on one's body the patient as jacket.

14. a passive type physiological moniyoting equipment that is used for monitor patient physiological comprises:

A plurality of pick offs, described pick off is used for detecting data on one's body by being placed on the patient, in described a plurality of pick off each includes a piezoelectric film, described piezoelectric film comprises and is used to detect from the data of body and described detection data transaction is become the polymer of voltage measurement, described polymer comprises Kynoar (PVDF), wherein said a plurality of pick off comprises many to pick off, describedly many pick off is used to detect from described patient's described detection data and is used for testing environment noise independently;

With each transducer of communicating by letter in described a plurality of pick offs, be used for described detection data data transaction is become signal;

With the accountant that described transducer is communicated by letter, the data after being used to receive and calculate described signal and being used to export calculating; And

With the instrument that described accountant is communicated by letter, be used for carrying out real-time, interactive, and be used to show data after the described calculating with described device.

15. equipment according to claim 14, in wherein said a plurality of pick off at least one is arranged in from the following group of substrate of selecting, a described group of part, support, bed, stretcher, cervical region collar, flak jackets, body protection protector, uniform, extraction element, exercise equipment, furniture, mat, seat and backrest that comprises clothes.

16. equipment according to claim 14, wherein said a plurality of pick offs are configured to a plurality of position measurement pulse wave velocities on one's body described patient.

17. equipment according to claim 14, wherein said a plurality of pick offs are configured to a plurality of position measurement pulse wave passing times on one's body described patient.

18. equipment according to claim 1, wherein said at least two pick offs comprise a sensor array, and pick off wherein is distributed in diverse location, are used to measure and monitor described detection data from described patient.

19. equipment according to claim 18 further comprises the stretcher of incorporating described sensor array into, is used for when described patient is positioned on the described stretcher, measures from described patient with from the acoustics and the hydraulic pressure signal of described adjacent domain.

20. equipment according to claim 19, wherein said acoustics and hydraulic pressure signal comprise from patient's physiological signal with from the ambient signal of described adjacent domain.

21. one kind is used for the method for monitor patient physiological passively, described method comprises:

Placing first piezoelectric transducer contacts with the patient;

Second piezoelectric transducer be placed on the patient near but on the discontiguous position;

Detect physiological signal and ambient signal with described first sensor, use the described second sensors sense environmental signal simultaneously;

Described physiology and ambient signal are converted to physiology and environment digital signal;

By from the signal that described first sensor detected, deducting the ambient signal that described second pick off is detected, separating in described physiology digital signal and the described environment digital signal; And

Show described physiology digital signal.

22. method according to claim 21 further comprises with band filter leaching described ambient signal.

23. method according to claim 21, wherein said detection comprise machinery, heat and acoustic signal are detected.

24. method according to claim 21 further comprises:

Away from the position of described first sensor the 3rd pick off is being placed on one's body the described patient; And

With the described first and the 3rd sensor measurement pulse wave velocity.

25. an equipment as claimed in claim 1, wherein first sensor contacts with described patient, second pick off be in around the patient but not with environment that described patient contacts under.

26. equipment according to claim 25, wherein said processor compares the physiological signal and the ambient signal that are detected by described first and second pick offs respectively, so that isolate described physiological signal.

27. equipment according to claim 1, wherein first sensor is positioned at primary importance, second pick off is positioned at the second position, and wherein said processor is determined pulse wave velocity according to the time difference of the physiological signal between described first sensor and described second pick off.

28. equipment according to claim 27, wherein said processor is according to described pulse wave velocity calculating blood pressure data.

29. method according to claim 24 further comprises described pulse wave velocity is converted to systolic pressure and diastolic blood pressure data and shows described blood pressure data.

30. method according to claim 21 further comprises:

In position, the 3rd pick off is placed on the described patient away from described first sensor; And

The pulse wave passing time of measurement between described first sensor and described the 3rd pick off.

31. method according to claim 30 further comprises described pulse wave passing time is converted to systolic pressure and diastolic blood pressure data and shows described blood pressure data.

32. method according to claim 21, wherein said detection step comprise, see through one deck or multilamellar clothes, flak jackets or the described physiological signal of its combine detection.

33. one kind is used for the method for monitor patient physiological passively, described method comprises:

First piezoelectric transducer is placed on the described patient;

With described patient near but on the discontiguous position, second, third piezoelectric transducer is placed on the patient;

By from the signal that described first sensor detected, deducting the ambient signal that described second pick off is detected, described physiology digital signal is separated from described environment digital signal; And

Show described physiology digital signal.

34. method according to claim 33 further comprises:

In position, the 3rd piezoelectric transducer is placed on the described patient away from described first piezoelectric transducer;

With described the 3rd sensor physiological signal and ambient signal; And

Comparing, to determine position on one's body at described first and second pick offs of described patient from the described physiology of described first sensor and ambient signal and from the described physiology and the ambient signal of described the 3rd pick off.