DE681948C - Device for bloodless measurement of arterial blood pressure - Google Patents

Description

Device for bloodless measurement of arterial blood pressure Zur For bloodless measurement of arterial blood pressure, two are expediently used one after the other around one and the same link, e.g. B. the arm, lying around inflatable Pouches or cuffs. One of the bags close to the heart has the task, on the one hand, of the - pulsating pressure fluctuations occurring in the other sac distant from the heart influence, on the other hand, to drive a registration track via an expansion body, on the one moved depending on the pressure conditions in the other bag Register pen writes. The pressure is increasing or increasing in the whole system. reduced, by choosing a large capacity of one expansion body care is taken that the pulsatory fluctuations in the heart Changes in pressure occurring in the bag are not registered. The increasing or decreasing pressure in the pouch close to the heart is intended to achieve a drive that is as uniform as possible create the registration path. This measurement method also requires that during the Measurement the entire system is pneumatically interrelated.

In order to be useful for the bloodless measurement of the arterial blood pressure Values to come, d. H. both the so-called primary and the so-called secondary criteria to capture, one has already gone over to it, in the pouch near the heart also the to detect pressure changes attributable to pulsatory fluctuations, and in a separate curve. The sudden increase in the size of the oscillations when the air pressure in this cuff near the heart is above the diastolic blood pressure is increased, or the sudden decrease of the same, if this blood pressure falls below the so-called magnioscillatory criterion of the dias.tolischeri Pressure, a primary criterion.

The same applies to the systolic blood pressure. In this case arises the diastolic blood pressure as the lower limit point, the systolic blood pressure as the upper limit of the zone of large oscillations. _ Not just the size, but also the shape. of the graphically recorded pulse images changes when the limit points are exceeded. Immediately above the lower one At the limit point, the pulse line at the lowest point of the diastole shows an otherwise non-existent one short depression, a sharp notch. This represents the form-oscillatory criterion diastolic blood pressure, also a primary criterion.

The secondary criteria cannot now help the heart with this closer cuff can be detected. Rather, these can only be achieved through the The second lying on the same limb, at a greater distance from the heart Identify the cuff, the so-called peripheral cuff.

As soon as the air pressure is closer to the heart than central designated cuff, the sy stolic, d. H. exceeds the maximum blood pressure, the measuring artery collapses and remains permanently collapsed. The pulse wave no longer passes the compression stretch. The pulse in the peripheral arteries disappears so that pressure fluctuations in the peripheral cuff do not occur. As soon as the air pressure is lowered again below the systolic blood pressure, it reverses the pulse peripheral, low; There are pressure fluctuations in the peripheral cuff. This criterion is called the palpatory criterion of systolic pressure.

In order to also capture this palpatory criterion, is known in Way a separate record of the pressure fluctuations in the peripheral cuff performed. The person performing the measurement has the after completion of the measurement to compare the two separate measurement curves and to draw their conclusions from them.

Comparing the two curves takes time and experience. failure in determining the result are not excluded. The simultaneous Writing two curves makes the construction of the device complex and the handling difficult.

In order to remedy this, it is already known that the pressure conditions in one bag as the abscissa and that in the other bag as the ordinate in one and the same To apply curve. The invention relates to such a known device for bloodless measurement of the arterial blood pressure, the pulse pressure on two consecutive Put the same limb in opposition to pressure, depending on an increase or reducing the pressure at the point closer to the heart drives a registration track and on this the pressure changes attributable to the changing pulse pressure records in the other location. However, the invention consists in that also the changes in pressure on the due to the changing pulse pressure closer to the heart act on the drive of the registration path, so that the on the trajectory recorded curve in both the abscissa and the ordinate Curve deflections caused by pulsatory fluctuations that can be used as criteria contains. Here only the pressure in the cuff near the heart has to be continuous or intermittently increased or decreased, while the pressure in the other, distant from the heart Cuff can be kept constant.

A suitable device consists of in a manner known per se two inflatable bags suitable for attachment to a limb and two with expansion bodies connected to the bags, one of which Registration pen, the other moves a registration path; according to the invention here stands one bag only with one and the other bag only with the other expansion body in connection and both systems are separated from each other. Both of them can Expansion body to be connected by a lockable line. The one moving the pen Expansion body is useful in a closed, with the interior of the associated Bag connectable housing arranged and in this case has a capillary, with the interior of the housing connecting opening. The drawing shows an embodiment in FIG a device for carrying out the measurement in elevation and partial section, Fig. A the connecting pieces of the device in section and in Fig. 3 one with the help the device according to the invention recorded curve, for the sake of simplicity is shown stretched (developed).

The device consists of two expansion bodies i and a. The expansion body i is formed by a Bourdon tube that has a sliding on its free end 3 Sleeve q. wearing. On the sleeve q. attacks a thread 5, which is on the drum 6 a Rotary shaft 7 is wound. A pointer 8, which sits rigidly on the rotating shaft 7 is designed centrally as a disk 9, on which a registration sheet is placed can be. A measuring scale i i is arranged under the pointer 8, which shows the pointer deflections read allowed. The inside of the Bourdon tube i is over a line 12 and a nozzle 13 with a pressure generator, for. B. a rubber ball, connected, which carries an exhaust valve.

The channel 12 corresponds to a channel 14, and mediates over a negative connector 16 connecting to the central sleeve while the channel 1 5 leads via the positive connection piece 17 to the peripheral cuff.

The interior of the expansion body 2, which is in a tightly encompassing housing 18 is located. The interior of the housing 18 is via a Channel i9 connected to channel 15. In the mutual confluence there is a three-way hahri 2o, which connects all cavities of the system with each other in one position and in the other position the tube i, the rubber ball and the central cuff with respect to the housing 18, the expansion body 2 and the peripheral sleeve separates. In addition, the interior of the housing 18 is still separated in the final position from the interior of the expansion body 2, so that this only with the peripheral Cuff communicates.

The interior of the expansion body 2 is also about a small capillary opening with the interior of the housing 18 connected. The capillary opening has the purpose of ensuring that slowly occurring pressure fluctuations equalize each other, so a registration of the same does not take place.

The expansion body 2 presses with a projection 21 on a rotary lever 23, which is mounted on a vertical rotating shaft 22, which receives the pointer 24 serves. For this purpose, the pointer 24 has next to its rear end on both sides protruding pins 25, which in corresponding notches of an attachment 26 of the rotating shaft 22 hooked in «-ground. The pointer 24 is thus through the expansion body: 2 pivoted about the axis of rotation 22 and is also due to the pins 25 in a vertical position Direction movable so that the writing tip provided with an ink well 27 rests on the registration disc io with slight pressure.

For the sake of clarity, the two cuffs are not shown, nor are the rubber balls and the outlet valve. As can be seen from FIG. 2, the hose 28 leading to the central cuff has a positive connection piece 29 which can be inserted into the negative connection piece 16. Conversely, the hose connection 3o to the peripheral cuff is provided with a negative connector 31 which can be plugged onto the positive connector 17 '. The different choice of the positive and negative connections 29 and 31 of the hoses 28 and 30 has the purpose of preventing incorrect connection of the cuffs.

The procedure for measuring blood pressure is as follows: The registration sheet io is attached to the disk 9. Both cuffs will created. The nozzles 29 and 31 are pushed onto the nozzles 16 and 17. aside from that . the rubber ball is connected to the nozzle 13. The three-way cock 2o takes it open position shown in FIG.

Now it is inflated with the help of the rubber ball until the tonometer pointer 8 largest oscillations can be recognized, whereby the pressure in the device is between the diastolic and systolic blood pressure. Now is the three-way cock rearranged in such a way that, as mentioned above, the central cuff and the Expansion body i on the one hand and the peripheral cuff and the expansion body 2 on the other hand are separated from each other. Moreover, the cock is in this position 2o also the separation between the interior of the housing 18 and the interior of the expansion body 2 completed. Now air will continue to be pumped in until a pressure is reached that is certain is above the systolic blood pressure. The pressure increase has an effect the closed position of the cock 20 only in the tube i and the central cuff the end.

Now the pointer becomes 2d. hung and pivoted into the registration position. The pointer can also be hooked in before the first manipulation begins take place; because it is provided with a weight load at its rear end, which allows the pointer to remain in the upright position while id he when the position is pivoted in the working position under the effect of its own weight easily rests on the registration sheet io. The registration sheet io, which is shaped like an arc of a circle running graduation lines is provided, is placed so that when printing Zero in the system the pointer tip towards the graduation o on the registration sheet scale come to lie.

The air outlet on the rubber ball is carefully opened and now begins immediately the spelling. During this writing the outlet gradually becomes emotional turned up further to achieve that the pressure drop occurs evenly and Each pulse beat always corresponds to a pressure drop of approximately 2 to 5 cm water column. The pressure drop in the central cuff corresponds, of course, to the same pressure drop in the tube i with the effect that the disk g rotates with the recording sheet io will. Has the Disk 9 or pointer 8 reaches zero, so the writing is finished. The writing lever 24 is turned up and the changeover cock 2o is opened again. All cavities in the measuring device are thus emptied and the registration sheet io is removed.

A second measurement can be made immediately. In so far such a case If the same person is to be made, it is not necessary to blow off all of them Drain cavities. Rather, after completion of the first measurement and after Remove the registration sheet and close the drain valve on the rubber ball again and after applying a new registration sheet, air is pumped in again, without the three-way cock being moved into the open position.

When reading the curve are the two components that make it up has grown together, namely the abscissa length originating from the central cuff and to mentally separate the ordinate height resulting from the peripheral cuff. At the change of the height of the ordinate or the pulse image height, one can use the svstölischen and read off the diastolic blood pressure, measured by the pelpatory criterion. Of the systolic blood pressure is fallen below with falling cuff pressure with the first pulse, which in the hitherto smooth circulatory line 32 has a stop 33 in radial Direction causes the diastolic pressure with the first pulse at which the rash occurs 34 has reached its permanent full size in the radial direction and no more increases.

The air pressure in the central cuff drops while the curve is being written constantly, since the air outlet is open. During the systolic rise of the Pulse wave but it rises temporarily because the blood wave billowing in through the the volume reduction caused by the air outlet overcompensates. The disks 9, io, which are now driven depending on the pressure in the central cuff, accordingly move backwards for a moment, the abscissa decreases from instead of to. The decrease in the abscissa 35 is the more extensive, the faster and the more the systolic rise is higher. It is an approximate measure of this speed and height. At the point at which the retrograde abscissa suddenly and reduced by leaps and bounds, lies the lower limit of the large oscillations. Man reads the diastolic pressure there. It is also noted that the beginning of toe 35 above, marking the systolic rise in the central cuff this limit point is significantly longer than below. This long toe of the The curve corresponds to the abovementioned depression of the pulse pattern immediately above of the lower limit point in the separate recording of the curve from the central one Cuff. The long toe is thus the form-oscillatory criterion of the diastolic Pressure. It often presents itself as a loop, which, however, is useful for the diagnosis of the Border point is irrelevant.

The magnioscillatory criterion of the systolic pressure, ie the upper limit of the large oscillations, or the sudden increase in size when the cuff pressure falls, can generally not be determined on the curve, since the smooth circular line 32 is shown above this limit point, but not on the details are recognizable. Every now and then, however, 32 stronger and weaker sections are noticeable on this line. The heavier sections are due to the fact that there the writing tip moves back and forth and has therefore released more ink than on the weaker ones. The heavier sections thus correspond to the declining abscissa. Their lengths are a relative measure of speed and altitude. One now notices, provided that these sections can be distinguished, that their length suddenly increases at the upper limit point. This jump represents the magnioscillatory criterion of the systolic pressure in the curve.

It can be seen that the single curve can be read off the same criteria permitted, which would otherwise be sought out separately on the known two curves and with each other need to be compared.

By combining criteria in a single curve, too the detection of which required two separate curves with the previous devices, the apparatus is made smaller, the handling simplified, the reading easier, Avoided error and the reliability of the measurement especially of the diastolic Blood pressure increased significantly.

Instead of the volume and pressure fluctuations of a link section other pulsatory processes, e.g. B. the pulse rate of a single artery recorded will. Above all, it makes sense to arrange the blood pressure measurement so that the changing Pressures and pulsatory pressure fluctuations on the upper arm cuff, as described here, be used to move the writing surface, but that the pulse is peripheral from the Compression site is detected by a normal pulse recording. It will i.e. the registration surface on which the pulse curve is written instead of how usual, by a clockwork, by the pressure in the Upper arm cuff moves .. A pulse recorder with air transmission, as already indicated by Mar ey, would be suitable for this.

Claims (5)

PATENT CLAIMS: i. Device for bloodless measurement of the arterial Blood pressure, which is the same as the pulse pressure at two consecutive points Limb pressure opposite, depending on an increase or decrease of the pressure at the point closer to the heart drives a registration track and on this the pressure changes on the other due to the changing pulse pressure Place records, characterized in that also the changing pulse pressure changes in pressure at the point closer to the heart to the drive (1, 3, q., 5, 6, 7) of the registration path (io) act so that the on the registration path recorded curve both in the abscissa and ® also in the ordinate as criteria contains usable deflections (35) caused by pulsatory fluctuations. 2. Apparatus according to claim i, consisting of two inflatable, for attachment bags suitable on one limb and two connected to the bags Expansion bodies, one of which is a registration pen, the other a RegistrieAahn moves, characterized in that the one bag only with the one (i) and the other bag is only connected to the other expansion body (2) and both systems are separate from each other. 3. Device according to claim i or 2, characterized in that the two expansion bodies (1, 2) by a lockable Line (15) are connected. q. Device according to claim 1, 2 or 3, characterized in that that the expansion body (2) moving the registration pen (27) is in a closed, is arranged with the interior of the associated bag connectable housing (18) and has a capillary opening corresponding to the interior of the housing. 5. Device according to claim 1, 2, 3 or q., characterized in that the in the connecting line (15) of the two expansion bodies (1, 2) lying blocking element as a three-way valve (20) is formed and in the blocking position both the two expansion bodies (1, 2) with the associated bags separates from each other as well as the expansion body (2) from the enclosing housing (18).