Background technology
For continuous measurement human body arteriotony all the time, so that monitor and follow the trail of the instantaneous variation of human blood-pressure incessantly, for many years, tradition adopts and insert conduit in shallow table arteries (maximum is the radial artery of wrist) clinically, arterial blood is introduced pressure transducer carry out direct gaging method.Because this traditional method has wound, all the time exist complicated operation, cause suffering (so this pressure testing method can only under narcotism, carry out) to patient, easily cause bleeding after particularly using, problems such as complication such as infection, thrombosis, thromboembolism and nerve injury or sequela.
For this reason, people had studied multiple no wound continuous blood pressure measuring method in the last few years, and wherein the most noticeable is the method for a kind of being known as " blood vessel no-load method " (or " method is decided in the volume embedding ", " cubage compensation method ").Based on this method, (Cs 133205,1969 once to have developed several blood pressure measuring devices abroad; US4510940; US4524777,1985; US4869261,1989 etc.), what wherein have also becomes commercialized (as FinapresTM2300, Ohmeda).According to the method during Wound-less continuous blood pressure measuring, the general volume pulse wave that a photoelectric probe detects tested tremulous pulse (promptly because arterial blood tube wall with the beat variation of arterial volume of generation of blood pressure ripple wherein) that adopts, control the pressure in the air bag (or water pocket) on the skin surface that is fixed on tested tremulous pulse top simultaneously, make the blood vessel wall of tested tremulous pulse except be subjected to original blood pressure ripple effect in the inboard, also be subjected to external pressure effect simultaneously in the outside, and then make the volume pulse wave of tested tremulous pulse change.Be changed to a certain feature by the volume pulse wave of tested tremulous pulse (for example the small vibration wave amplitude that artificial stack is got on its amplitude or the volume pulse wave reaches maximum when this feedback control makes, perhaps the descending branch of its curve show baseline height when recessed, its baseline height (meansigma methods) drop to this tremulous pulse and begin emptying 1/3 etc.) when occurring, illustrate at this moment the blood vessel wall of tested tremulous pulse be the most soft at it, promptly do not have under any circumferential tensile what is called " idling " and beat.At this moment connecting a servo amplifying circuit is amplified this volume pulse wave, and remove further to control the pressure of air bag (or water pocket) with it, make be added in the tested arterial blood tube wall outside pressure not only waveform in shape and also all identical on the size at waveform with this endarterial blood pressure ripple, be that inside and outside both sides stressed of tested arterial blood tube wall is when reaching dynamic equilibrium, the blood vessel wall of tested tremulous pulse will no longer be beaten with endovascular blood pressure ripple, on the volume when its capacity of blood vessel will be fixed on its idling by embedding.At this moment need only the force value of measuring air bag (water pocket) with pressure transducer continuously, can realize the continuous blood pressure measurement.
Owing to make easy and simple to handlely in this way, need not calibration, and measurement result is not subject to the moving interferential influence of patient body, thereby is a kind of no wound continuous blood pressure measuring method that is suitable for clinical practice comparatively speaking.But also there is following point in this method: 1. this method generally is used in and measures the finger arterial pressure on the finger.This mainly is owing to be convenient to realize that photoelectricity capacity of blood vessel ripple detects on finger, also is convenient to fix, and is also less to the influence of limbs compressing simultaneously.But the finger tremulous pulse belongs to the peripheral arteriole big to resistance of blood flow, thereby whether just often used the blood pressure of the finger position what is called " systemic blood pressure " (i.e. the aortic blood pressure of close heart) with generally judging patient's blood pressure clinically compared, even under normal circumstances also will hang down about 10mmHg, if this difference can reach tens of mmHg under the arteriosclerosis situation.The more important thing is because big than in the large artery trunks blood vessel wall of the smooth muscle composition in the small artery blood vessel wall, and these vascular smooth muscle compositions very easily are subjected to the influence of various factors (such as cold, anesthesia etc.) to produce contraction or diastole, cause that blood pressure changes significantly in the small artery, to such an extent as to can not be used to reflect patient's systemic blood pressure with the pressure value that the finger tremulous pulse records at all in many occasions.Especially ought run into patient's the very poor occasion of circulatory function, the finger tremulous pulse occurs vascular smooth muscle sometimes and extremely shrinks and cause intra-arterial to lose blood, to such an extent as to can't measure blood pressure on finger.The general tubular air bag (water pocket) that adopts carried out full week pressurization to the middle joint or the base pitch of finger when 2. this method was to the pressurization of finger tremulous pulse.Because in the continuous blood pressure measuring process, pressure in the air bag (water pocket) always remains between finger systolic pressure of tremulous pulse and the diastolic pressure and changes, though this pressure for the tremulous pulse of pressed part only can cause blood flow to a certain degree decline and can not cause bloodstream blocking, but all vein blood vessels and the capillary blood flow of pressed part are blocked fully, cause that tested subordinate swims finger congestion, thereby be unsuitable for the long-time continuous use.At the problems referred to above 1., once the someone carried out this blood vessel no-load principle is used for the trial that brachial arterial pressure is measured at the upper arm position.Its result shows, can record near aortic systemic blood pressure though do like this, but it is because very dark in the position of upper arm place brachial artery, to oppress brachial artery fully and must carry out the pressurization in full week or approaching full week, thereby will make that in a short period of time the whole forearm in its downstream and the blood circulation of hand are seriously influenced upper arm; In addition, at the problems referred to above 2., also once the someone carried out this blood vessel no-load principle is used for the trial that head is measured the temporo arteriotony.Its basic point of departure is that head has abundant tremulous pulse, venous rete, if adopt a little air bag (water pocket) only to oppress the temporo tremulous pulse, even long-time continuous is measured blood pressure the head blood circulation is affected.But in fact in the fixing difficulty of temporo tremulous pulse place air bag, symptom such as particularly fixedly the bandage of usefulness can be oppressed the occipital bone tremulous pulse and the occipital bone vein of back head, and long-time continuous is used and also can be caused patient's headache, and is dizzy.And the temporo tremulous pulse also belongs to peripheral arteriole, and the pressure value that records on the temporo tremulous pulse can not be used for reflecting patient's systemic blood pressure well.
Summary of the invention
The method and apparatus that the purpose of this invention is to provide a kind of Wound-less continuous blood pressure measuring, it can correctly measure the systemic blood pressure of human body, and the blood flow circulation in downstream, tested position is not influenced basically.
For achieving the above object, the solution that the present invention adopts is: the measuring point of existing blood vessel no-load method, promptly arteries is carried out that volume detects and the position of external pressurized is changed on the suitable position of wrist, and adopt a local pressurizing device only to oppress a radicular arteries in wrist two radicular arterieses (radial artery and ulnar artery).
The present invention is based on: though 1. the diameter of radial artery or ulnar artery is smaller than the diameter of upper arm place brachial artery, but it is arteriolar much larger than finger tremulous pulse and temporo tremulous pulse etc., and the smooth muscle composition in the blood vessel wall of radial artery or ulnar artery is less than in finger tremulous pulse and the temporo tremulous pulse, so the blood pressure of radial artery or ulnar artery than finger tremulous pulse and temporo tremulous pulse more near the human body systemic blood pressure, also be much smaller by the influence of various factors.Even and, on radial artery or ulnar artery, generally also can measure the capacity of blood vessel ripple, and the situation that blood pressure measurement can't carry out can not occur in the very poor occasion of patient's circulatory function.Particularly, be convenient to reasons such as operation owing to the These characteristics of wrist tremulous pulse and in wrist portion, the radial artery at wrist position has the direct pressure measurement of wound to be applied to operation and critical illness monitoring by countries in the world as the most frequently used blood pressure measuring method for many years always, to such an extent as to the pressure value of wrist tremulous pulse always by clinical worker custom as the most reliable, the criterion of human body systemic blood pressure the most accurately, thereby utilize blood vessel no-load method Wound-less continuous blood pressure measuring to have high clinical use value at the wrist position.2. tremulous pulse that the normal person is bigger at the wrist place and vein are all more than two, and wherein two radicular arterieses (radial artery and ulnar artery) are interconnected by two archs of aorta at the inner quilt of palm, and several veins also are interconnected by dorsal venous rete of hand at the back of hands.Even if being interconnected between these blood vessels guaranteed to make certain radicular arteries of wrist portion or/and the part vein is blocked for a long time, but another radicular arteries and other most veins are when still can blood flow unimpeded, and the blood circulation of hand can not be affected basically yet.Thereby, utilize the blood vessel no-load method can realize not having for a long time the wound continuous blood pressure on the radicular arteries in wrist radial artery and ulnar artery and measure.In fact, because radial artery and ulnar artery location tables when passing the wrist position are shallow, and apart from each other, several veins also disperse in the distribution at wrist position very much, can also guarantee when wrist portion accomplishes only a radicular arteries fully to be oppressed that another radicular arteries and unimpeded being not difficult of other most venous blood flows realize.In addition, implement this no wound continuous blood pressure in wrist portion and measure, advantage such as obviously easy to operate in addition, that pressue device is easy to fix.
The specific embodiment
The present invention is described in further detail with embodiment below.
Fig. 1 is the general diagram of one embodiment of the present of invention.It shows that present embodiment comprises the two large divisions, and wherein first is a wrist unit 1, mainly is the device that the wrist tremulous pulse is carried out volume detection and external pressurized; Second portion is a measurement-feedback control system 2.In order to stress how the present invention realizes utilizing the blood vessel no-load method not have the wound continuous blood pressure in wrist portion to measure, and the second portion measurement-feedback control system 2 in the present embodiment has directly adopted the measurement-feedback control system among the existing early production Finapres TM2300.
At first to the first among this embodiment---wrist unit 1 describes.As shown in Figures 2 and 3, be the radial artery 11 of wrist portion and the radial artery in the ulnar artery 12 to be carried out volume detect and external pressurized at present embodiment, thereby realize that the continuous blood pressure of radial artery is measured.This wrist unit 1 comprises radial artery pressurised airbag 3, inflatable bag fixing band 4, and the fixing holder 6 of radial artery volume probe 5 and wrist is totally four parts.
Radial artery pressurised airbag 3 is flat round balloons.For the pressure that guarantees this air bag can pass to the degree of depth at radial artery 11 places fully, on the one hand, the fixed position of this air bag should make its center can aim at the radial artery of showing shallow place most that is in of wrist portion; On the other hand, the diameter of this air bag should be big fully, but excessively can be urged to another root ulnar artery 12 and other vein blood vessels simultaneously, can increase the volume of air bag simultaneously, thereby make the pressure in the air bag be difficult to obtain quick control, so this diameter is chosen as wrist diameter half (for example can be selected in 30-40mm for general adult).In addition, in order to guarantee that this air bag 3 produces circumferential tension force and influences effective compressing to radial artery in being unlikely to because of the wall of expansion at it after the inflation, that the wall 7 towards inboard (wrist) of this air bag adopts is thin and soft, have certain elastic trnaslucent materials makes, and make it have the shape of protruding to the inside, and the wall and the wall toward the outer side along circumference one circle of this air bag adopt the material with certain degree of hardness to make.
Inflatable bag fixing band 4 is used to pressurised airbag 3 is fixed on the above-mentioned wrist location.In fact, for simplified structure, present embodiment has been made one to air bag 3 and bandage 4, promptly adopt the bandage that certain thickness and hardness are arranged, on the position corresponding to air bag of the face of wrist, process a diameter flat round pool identical at it with air bag 3 diameters, then the edge of above-mentioned air bag medial wall 7 made from thin film is bonded on the edge of pit of bandage 4, this cavity with certain degree of hardness constitutes above-mentioned air bag 3 on this air bag medial wall 7 made from thin film and the bandage 4 thereby utilize.Because the intrinsic pressure of above-mentioned air bag 3 will be cooked pulsatile change according to the blood pressure of radial artery 11 when utilizing blood vessel noinvasive method continuous blood pressure measuring, also be unlikely to beating of any direction taken place under the intrinsic pressure effect of this big pulse for the position that guarantees this air bag and cause feedback control system self-oscillation, this bandage 4 all should have certain rigidity on the whole, and the fixing of its two ends should adopt the device with non-telescoping property.In the present embodiment, the two ends of this bandage 4 are utilized velcro 8 and are fixed in the fixing holder 6 of wrist.In addition, the material of this bandage 4 also should have certain elasticity, and when attenuating slightly after being subjected to long-time continuous compressing with convenient wrist, its rebound performance can also make it to be fastened on air bag on the wrist can not become flexible.On the other hand, in order to guarantee only fully to oppress tested radial artery by air bag 3, and reduce the pressure of 4 pairs of other parts of wrist of bandage as much as possible, thereby in order to avoid block the blood circulation that another root ulnar artery and most vein influence its downstream hand, effective contact area of this bandage and wrist should be greater than 3 times of the pressurization area of air bag 3, should adopt big as far as possible bandage width (should be greater than 50mm for general adult) for this reason and make bandage towards the mask of skin the concaveconvex shape that matches in wrist be arranged.
Radial artery volume probe 5 is reflective photoelectric sensors.Be fixed on the wrist with above-mentioned air bag 3 for the ease of utilizing bandage 4 to pop one's head in, and do not hinder air bag to be adjacent to the wrist surface, this is popped one's head in by the inside of the above-mentioned air bag of interior plant.This probe is made of a luminescent device 9 and a photoelectric device 10.These two devices 9 and 10 are sticked on the inner surface of the medial wall 7 that makes with semitransparent thin film of above-mentioned air bag 3 by the interval with 5-10mm.During stickup, should make the sensitive surface of the light-emitting area of luminescent device 9 and photoelectric device 10 towards the inner surface of thin film medial wall 7, and make that line and radial artery direction of travel between these two devices 9 and 10 are perpendicular, promptly along the length direction of bandage; Make the center of the midpoint alignment thin film medial wall 7 of line simultaneously, to protect when the centrally aligned wrist of air bag 3 is shown the radial artery 11 at shallow place most, these two devices 9 and 10 can be positioned at the both sides of radial artery on the wrist surface, just make the center of the detection range of this volume probe just in time aim at radial artery.When volume probe 5 is used to detect the capacity of blood vessel variation of radial artery 11, wrist inside is injected in the medial wall 7 that makes with semitransparent thin film of the light transmission air bag 3 that luminescent device 9 wherein sends, through wherein radial artery 11 and surrounding soft tissue reflex in the photoelectric device 10.Because the capacity of blood vessel variation of radial artery 11 can cause and reflex to the intensity variation in the photoelectric device 10 and then the output current of photoelectric device 10 is changed, volume probe 5 just can convert the volume of radial artery the output of to radial artery volume pulse wave signal with the variation of blood pressure ripple thus.
The fixing holder 6 of wrist is used to fixedly palm with respect to the angle of wrist, and wrist is with respect to the close elbow joint part of forearm angle, to guarantee that measuring in the process of blood pressure the measured in long-time continuous any body occurs when moving, pressurised airbag 3 and volume probe 5 positions with respect to radial artery 11 remain constant.Simultaneously, use of this fixing holder can also be played the effect of the pressure that disperses 4 pairs of wrist dorsal parts of bandage that fixation balloon uses.The fixing holder 6 of this wrist is supporting plates made from the hard material that certain intensity is arranged, its length and width should guarantee to cover from the finger base pitch to the dorsal part demifacet near whole the back of the hand, wrist and the forearm of elbow joint, and its shape should guarantee that its medial surface can be in the back of the hand, wrist dorsal part and postcubital shape kissing and (therefore, in order to adapt to the forearm of different length, thickness, it is standby to do several fixedly holders respectively).Being fixed with the little bandage 15 that several ends are sewed with velcro in the fixing holder 6 of this wrist is used for measured's forearm, wrist and hands are tied up in the fixing holder 6 of this wrist.For avoiding the fixing holder measured of causing really up to the mark uncomfortable, can glue the liner 16 of one deck soft material at the medial surface of fixing holder, but this liner is unsuitable blocked up, soft excessively, otherwise can influence the fixed effect of wrist, simultaneously also can be when air bag be intrinsic pressure when making significantly pulsatile change with blood pressure, under the intrinsic pressure effect of the pulsation of air bag, produce the feedback control system of beating and produce self-oscillation to such an extent as to wrist occurs.
The following describes above-mentioned wrist unit 1 is how to be used to carry out radial artery not have the measurement of wound continuous blood pressure in the present embodiment.As shown in Figure 1; When utilizing above-mentioned wrist unit 1 to carry out the radial artery blood pressure measurement; Must serve as that measurement-feedback control system 2 of controlling purpose engages with one with the blood vessel no-load with this wrist unit.In the present embodiment, the method for this measurement-feedback control system 2 adopts and early stage does not a kind ofly have measurement-feedback control system among the wound continuous measurement DBP product F inapres based on blood vessel no-load method principle. combinations is very simple; Namely the lead-in wire of the luminescent device 9 in the radial artery volume probe in this wrist unit 15 and photoelectric device 10 respectively with measurement-feedback control system of Finapres in original being used for be connected to the output (this output is omitted in Fig. 1) of the luminescent device power supply of finger arterial volume probe and the plethysmogram signal input 17 of photoelectric device, simultaneously original being used in the voltage in measurement-feedback control system of the wireway of radial artery pressurised airbag 3 in this wrist unit 1 and Finapres-air pressure conversion equipment was connected to the wireway 18 of pointing artery pressurised airbag air feed.
When use does not have the wound continuous measurement by 2 embodiment dimerous of the measurement-feedback control system among above-mentioned wrist unit 1 and the Finapres to the radial artery blood pressure, at first measured's the back of the hand, wrist and forearm is fixed in the fixing holder 6 of wrist in the wrist unit 1, and then behind the shallow place of table of the tested wrist radial artery 11 of the centrally aligned of the air bag in the wrist unit 3, inflatable bag fixing band 4 is wrapped in wrist portion, and fixedly the two ends of bandage utilize the fixing holder 6 of velcro 8 and wrist to be fixed together.Finish said fixing and be connected the back start to measure-control system 2 of instead bursting enters automatic mode.When wherein blood pressure continuous measurement began, for the radial artery that finds and write down the measured volume when the idling, measurement-feedback control system 2 was at first received " open loop " position to duty switch 19.Under this operate in open loop state state, volume in the wrist unit 1 probe 5 converts the capacity of blood vessel of radial artery to radial artery volume ripple with the variation of blood pressure ripple, the voltage of service voltage-pneumatic pressure converter 21 is automatically regulated in gasbag pressure initialization circuit 20 beginnings in the simultaneity factor, and the air bag 3 in the wrist unit 1 is begun radial artery 11 external pressurized.Along with the increase of radial artery external pressure, radial artery volume wave amplitude and shape all will change.When radial artery volume wave amplitude reaches maximum, illustrate that the Artery Vein volume has been that the blood vessel idling is volumetrical has changed up and down at this with the variation of blood pressure ripple.At this moment system can make gasbag pressure initialization circuit 20 stop the pressure of air bag 3 is regulated, and makes a no-load volume memory circuit 22 write down at this moment the meansigma methods of radial artery volume ripple (direct current composition) as the idling volume V o of measured's radial artery.Find and remember under behind the idling volume V o as measured's radial artery, measurement-feedback control system 2 is automatically received " closed loop " position to duty switch 19, and the gain of the wherein servo amplifying circuit 23 of increase gradually, near the volume volume ripple of 5 detected radial arterys this idling volume of popping one's head in subtracted each other poor (being the Alternating Component of Artery Vein volume ripple) that obtain with the no-load volume V o that is write down by no-load volume memory circuit 22 by a comparison circuit 24 and amplified, and driving voltage-pneumatic pressure converter 21 removes to control air bag 3 and further applies the waveform pressure the same with its internal blood pressure waveform from the outside to radial artery 11, makes the amplitude of the volume ripple that radial artery produces with the internal blood pressure ripple begin to diminish.Owing to make pressure that air bag 3 is added in radial artery 11 outsides not only in shape at waveform when the gain of servo amplifying circuit 23 is adjusted to, and it is also fully identical on the size of waveform with the blood pressure waveform of radial artery inside, be that inside and outside both sides stressed of Artery Vein wall is when reaching dynamic equilibrium, the blood vessel wall of radial artery will no longer be beaten with endovascular blood pressure ripple, and the capacity of blood vessel of radial artery will be fixed on its idling volume V o by complete embedding.So under closed-loop working state, as long as the time point that makes system find the volume wave-amplitude of radial artery 11 finally to go to zero simultaneously in the gain that increases servo amplifying circuit 23 gradually, just can affirm that the air pressure that begins thus in the pressurised airbag 3 all equates with blood pressure in the radial artery 11 at any time, at this moment uses the intrinsic pressure no wound continuous measurement that can realize the radial artery blood pressure of the pressure transducer 25 continuous measurement pressurised airbag 3 that link to each other with pressurised airbag 3.
More than cited just one embodiment of the present of invention.In fact the present invention can have multiple enforcement and improvement project.
For example, in wrist portion two radicular arterieses, select a continuous blood pressure measuring not necessarily leave no choice but select radial artery can not, as second kind of embodiment of the present invention, the ulnar artery that also can select wrist portion is as tested tremulous pulse, its measuring method is identical with embodiment 1, does not repeat them here.
The third embodiment of the present invention be in keep capacity of blood vessel probe pressurised airbag on position, respectively be provided with one respectively corresponding to the radial artery of wrist portion and ulnar artery, and a switching device shifter is set, make them alternately carry out volume detection and external pressurized at set intervals to radial artery and ulnar artery.Its wrist unit as shown in Figure 4.This kind method more helps long-time continuous and measures blood pressure, can avoid oppressing for a long time pain and the numbness that cause in a place because be used alternatingly two radicular arterieses.
The 4th kind of embodiment of the present invention as shown in Figure 5.The fixing holder of wrist in the present embodiment adopts the polylith supporting plate to be combined into.Adopt adjustable bindiny mechanism (as universal joint) to interconnect between these supporting plates so that the wrist that these supporting plates are combined into fixedly holder can be adjusted to multiple shape shared and needn't make respectively for them for having difference measured fat or thin, the length forearm.
On the other hand, in the above-described embodiment, we have utilized a kind of measurement one feedback control system based on the device Finapres of blood vessel no-load method continuous blood pressure measuring that was used for originally pointing, wherein adopted the amplitude of tested arterial volume pulse wave whether to reach maximum as judging whether tested arteries is in the criterion of idling, and adopted and controlled air pressure and control the external pressure that tested tremulous pulse is applied.In fact, measurement-feedback control system among the present invention can be other the measurement-feedback control system based on blood vessel no-load method continuous blood pressure measuring, for example it can adopt other criterion (such as according to the shape of arterial volume ripple etc.) to judge the idling of tested tremulous pulse, also can adopt control hydraulic pressure to control the external pressure that tested tremulous pulse is applied.
In the above-described embodiments, the wrist unit that comprises tested tremulous pulse external pressurized air bag and volume detection probe is an independent device.In fact, because wrist has bigger weight capacity, thereby can be made of one the pressure transducer in the measurement-feedback control system, voltage-pneumatic pressure converter even The whole control system and above-mentioned wrist unit, the speed of pressurize feedback control so greatly, thereby further improve the blood pressure measurement precision, and can reduce line and pipeline when using, the clinical practice of being more convenient for.