Patent Application
20180161238
The present invention concerns an apparatus and a method for assisting a user during cardiopulmonary resuscitation.
When a person suffers cardiac arrest, cardiopulmonary resuscitation must be initiated immediately whenever possible. In this process, cardiac massage, in which a compressive force is exerted on the center of the patient's chest at a rate of approximately 100 to 120 times a minute, is of primary importance. This force presses the sternum down so that blood is forced out of the heart into the circulation. In the relaxation phases between compressions, the heart again fills with blood. Whenever possible, cardiac massage should be supplemented with ventilation.
In particular, in accidents and other emergency situations, there are often no medically trained personnel present. The performance of cardiopulmonary resuscitation, particularly cardiac massage, by a lay person is then decisive for the survival of the patient. Because of a lack of training and/or practice, however, lay persons are often incapable of correctly performing cardiopulmonary resuscitation. In particular, there is often uncertainty, for example regarding the point at which the compressive force must be exerted, the amount of compressive force to be exerted, how long the relaxation period between two compressions should be, and/or the frequency of the compressions. This uncertainty may be increased by the situation in which cardiac arrest occurs, for example in a traffic accident. Devices for assisting a user, specifically a medical lay person, during cardiopulmonary resuscitation have therefore been developed.
U.S. Pat. No. 5,496,257 describes a portable apparatus for assisting a rescuer in administering cardiopulmonary resuscitation on a patient having a housing that rests on the patient's chest so that compressive forces can be applied to the patient's chest by means of the apparatus. The apparatus has an on/off switch and visual and acoustic indicators. Moreover, a processor unit is provided that compares allowable values stored in a ROM chip with currently measured values and activates the indicators in order to help the rescuer correctly perform cardiopulmonary resuscitation.
WO 2004/056303 A1 discloses a device for use in chest compression in connection with cardiopulmonary resuscitation that is configured to emit a sound when the chest compression is performed with a force that exceeds a predetermined value and also emit a sound that indicates the desirable frequency of chest compression. After the device is placed in the correct position on the patient's chest, the user manually exerts pressure on the upper surface of the device. This causes a peg connected to an upper part of the device to be pressed against a contact connected to a lower part of the device, thus closing a power supply circuit of a microcontroller circuit. This activates an electronic metronome that emits a sound at a predetermined rate. A mechanical sound generator emits a click each time the user compresses the device. By comparing the mechanically emitted click with the sound produced by the metronome, the user can determine whether he/she is exerting the compressive force with the necessary strength and frequency. An electronic sound generator can be provided instead of the mechanical sound generator.
WO 2014/071915 A2 discloses a device for controlled cardiopulmonary resuscitation during cardiac arrest that is composed of a curved pressure transmission means connected at its ends to a flat, relatively rigid pressure-receiving element. The geometric dimensions of the device are approx. 10 to 25 cm in diameter and approx. 6 to 12 cm in height. In application, a mechanical pressure is exerted on the pressure transmission means, which generates a perceptible signal when a maximum exertion of force is reached, said signal resulting from the interaction of spring elements. In one embodiment, strain gauges can be arranged at the end of the pressure transmission means that send a signal to an electronic device, causing a perceptible acoustic or optical signal to be generated.
US 2011/0201979 A1 describes a system for cardiopulmonary resuscitation by guided active compression-decompression that is attached to the chest of a patient using an adhesive pad in order to exert compressive and decompressive forces. The system comprises a handle with a stem that contains a load cell for measuring the compressive and decompressive forces. In one embodiment for manual use, the system comprises a mushroom-shaped element with a handle that is attached to the upper surface of a flexible contact pad by means of a stem. The contact pad has an adhesive for fixing the contact pad on a surface of the patient's chest. In use, the device is placed approximately in the middle of the sternum on the patient's chest, and the user grasps the handle with both hands and exerts compressive force on it; after the compression stroke is completed, the user lifts up the handle to expand the chest.
U.S. Pat. No. 4,355,634 discloses a locator device for cardiac compression during cardiopulmonary resuscitation. The device comprises a rectangular elongated main body of unyielding foam plastic and top and bottom cushion-like foam layers attached thereto. A palpable tactile signalling device, which emits a signal when a predetermined compressive force is exerted, is arranged in a rectangular opening in the main body.
According to DE 202007009575 U1, a device for compressing a human or animal body comprises means for guiding the user in compression that emit a sound when the chest has been compressed to the correct depth. The device can be configured as a cushion or a bag.
The non-generic publication US 2007/0053504 A1 discloses a connection device of a flip-open cellular telephone which has a connecting section that rotatably connects two housing sections to each other.
An object of the present invention is to provide an improved device for assisting a user during cardiopulmonary resuscitation, in particular a device of the generic type which is improved with respect to production costs, simplicity and safety of use, and/or storage and transport capability. An object of the invention is also to provide an improved method for assisting a user during cardiopulmonary resuscitation.
This object is achieved by an apparatus according to claim 1 and by a method according to claim 15. Advantageous improvements of the invention are given in the subordinate claims.
An apparatus according to the invention is configured for assisting a user during cardiopulmonary resuscitation of a patient. “User” is understood here to refer to a person who administers cardiopulmonary resuscitation, without this implying any limitation on the persons in question. In particular, the user can be a medical lay person, but can also be a medically trained person, for example a trained first responder. Several persons may also perform the cardiopulmonary resuscitation, for example with multiple persons alternately or simultaneously carrying out cardiac massage and/or one or more other persons carrying out ventilation; in this case, the multiple persons carrying out the resuscitation will also be referred to as “the user.” The term “patient” used in the following refers to the person on whom cardiopulmonary resuscitation is performed, regardless of the cause and circumstances of the resuscitation. Use of the apparatus according to the invention will be described in the following with respect to a person, but it is understood that the apparatus can also be used on a manikin for training purposes.
The apparatus according to the invention comprises a force transmission unit, which is configured for transmission and detection of a force that can be exerted by a user during cardiac massage on the patient's chest. This force, which is exerted in a direction essentially perpendicular to the surface of the chest and is transmitted via the force transmission unit to the chest, is also referred to in the following as “pressing force” or “compressive force.” The apparatus is preferably configured only for exerting a compressive force on the chest and not for exerting a pulling force. The force transmission unit comprises a lower plate that can be placed on the patient's chest, which is preferably configured as an essentially flat, rounded disk. Here and in the following, the “underside” refers to the side facing the patient, and the “upper side” refers to the side facing the user. In particular, the lower plate may be a flat, circular disk having a diameter of approximately 5 to 12 cm. This size approximately corresponds to the size of the surface of the chest to which pressure is to be applied during cardiac massage. For example, the lower plate can be configured as a thin disk having a thickness of approximately 1 mm.
The force transmission device further comprises an upper plate that is arranged at a distance from the lower plate, in particular parallel thereto and largely congruent therewith, so that the upper and the lower plate essentially overlap each other. The upper plate is preferably configured identically to the lower plate, i.e. specifically as a thin circular disk with a diameter of approx. 5 to 12 cm and a thickness of approx. 1 mm. For example, the lower and the upper plate may be composed of a hard plastic.
A force sensor for detecting a force applied by means of the upper plate to the lower plate is arranged between the lower and the upper plate. For this purpose, the force sensor can in particular be adjacent to the lower and the upper plate and thus support the upper plate on the lower plate and transmit forces from the upper to the lower plate while simultaneously detecting said forces. If a compressive force is exerted on the upper plate perpendicularly to the surface of the plate, said force, when the lower plate rests directly or indirectly on the surface of the chest, is transmitted from the upper to the lower plate and further to the chest, and is simultaneously detected by the force sensor. In particular, the force sensor can emit an analog or digital sensor signal that represents the force detected by the force sensor and thus allows a conclusion to be drawn regarding the compressive force exerted by the user on the upper plate and transmitted by the force transmission unit to the patient's chest.
The apparatus according to the invention further comprises an indicator device configured for generating at least one signal that can be perceived by the user. In particular, the signal can be an acoustic, optical and/or haptic signal. Specifically, the type and intensity of the signal are such that it can be perceived under a wide variety of environmental conditions. More particularly, an optical signal is bright enough or an acoustic signal is loud enough to be reliably perceived by a user in every case at an accident site with widely differing bright illumination and e.g. loud traffic noises. Particularly preferably, the indicator device can be configured to generate signals that can be perceived via different sensory channels, for example for synchronous generation of an acoustic and an optical signal. Such redundant signals can make it possible for at least one signal to be perceptible with increased reliability under widely varying environmental conditions.
The apparatus according to the invention further comprises an electronic control device that is configured for controlling the indicator device based on the force detected by the force sensor or the sensor signal emitted by the force sensor. For this purpose, the electronic control device is connected to the indicator device and the force sensor, in particular via corresponding electrical wires. The electronic control device can comprise a microcontroller or a microprocessor, and can be configured for further evaluation of the sensor signal picked up from the force sensor, for example by comparison with predetermined target values.
According to the invention, the force transmission unit is embedded in a mat. The mat is configured to be flexible, i.e. bendable in at least one direction, and it is preferably slack. In particular, the flexible mat is configured in sheetlike form and has a larger surface than the force transmission unit, and in particular has an expansion many times greater than that of the force transmission unit. The mat should preferably extend beyond the force transmission unit on all sides. For example, the mat may be rectangular, rectangular with rounded corners, or configured in another form. The force transmission unit can be embedded approximately in the middle of the surface of the mat. In particular, the force transmission unit can be glued onto the mat. The force transmission unit is preferably completely enclosed by the mat, i.e. covered in particular both on the underside of the lower plate and the upper side of the upper plate by the material of the mat and also laterally enclosed by the mat; the flexible mat can thus be used to protect the force transmission unit from moisture or soiling. The flexible mat can serve as a mechanical carrier in order to improve handling of the force transmission unit. The flexible mat can further be used for more even distribution of the compressive force exerted by the force transmission unit over the patient's chest and for preventing any edges of the force transmission unit from injuring the patient. For example, the mat can also be configured as a pad or cushion or comprise such a pad or cushion. The control device and the indicator device can thus be completely or partially embedded in the flexible mat.
Because the force transmission unit is embedded in a flexible mat that extends beyond the surface of the force transmission unit, the apparatus according to the invention can be more easily and reliably placed on the chest of the patient on whom cardiac massage is to be carried out. In particular, this allows the apparatus to be more reliably placed, so that the force transmission unit rests more stably on the area of the surface of the chest to which pressure is to be applied in cardiac massage. In particular, the form of the mat can be adapted to physical characteristics, e.g. it can have a marking or an indentation for the patient's neck so that the mat can be aligned with the patient's neck and correct placement of the force transmission unit is facilitated. This improves the safety of use of the apparatus to assist cardiopulmonary resuscitation, in particular cardiac massage, even when this is carried out by a medical lay person. The flexibility of the mat allows it to be adapted to various physiological characteristics so that the apparatus according to the invention can be correctly placed on the chest regardless of the height, weight, and sex of the patient. As the mat is flexible, this also allows adaptation to various storage and transportation containers. Because the force transmission unit, and optionally the control and/or indicator device, is embedded in the flexible mat, which can be water-tight, it becomes simple to configure the apparatus as a whole to be water-tight, so that the apparatus is functional under virtually any environmental conditions. Finally, the mechanical complexity and spatial requirement of the apparatus can be reduced, reliability can be increased, and storage and transportation of the apparatus can be facilitated if at least one perceptible signal is generated on activation of the indicator device by the electronic control device and preferably no mechanical sound generation takes place.
Preferably, at least the lower plate is deformable for adaptation to the surface of the patient's chest, i.e. on application of the force required for the cardiac massage, the lower plate conforms to the shape of the surface of the chest such that the exerted force is distributed over a suitable area of compression of the chest, for example over a circular surface essentially arranged symmetrically to the sternum with a diameter of approximately 7 to 12 cm on the front side of the sternum. As the surface of the chest in the area of the sternum at which the compressive force for carrying out cardiac massage is to be exerted can be shaped differently depending on the patient, for example approximately level or curved inward, deformability of at least the lower plate allows more favorable distribution of the exerted force over the surface of the chest. Particularly preferably, the upper plate is also deformably configured in a similar manner, as well as the force sensor in the case of a flat configuration of said force sensor interposed between the lower and the upper plate. In particular, the force transmission unit is configured to be deformable as a whole with a stiffness greater than that of the flexible mat. The lower plate or the force transmission unit as a whole should preferably be configured in an elastically deformable manner. In particular, the stiffness of the to lower plate or of the force transmission unit can be specified such that when the latter is lying on a substrate with two edges opposite to each other, it yields in the middle relative to the edges by approximately one or more centimeters on exertion of a target force for the cardiac massage. For example, the lower and the upper plate can each be composed of a hard plastic. This can allow particularly simple distribution of the exerted force over a sufficient surface in virtually every case.
The flexible mat should preferably comprise at least two particularly flat layers between which the force transmission unit is embedded. The at least two layers are also configured to be flexible, and in particular are connected to one another in a planar manner. In a particularly advantageous configuration, the force transmission unit is embedded in the mat such that the underside of the lower plate is connected to the upper side of a lower layer and the upper side of the upper plate is connected to the underside of an upper layer of the mat. The at least two layers may be composed e.g. of rubber or a suitable foam. Because the mat comprises at least two preferably flat layers between which the force transmission unit is embedded, the apparatus according to the invention can be produced in a particularly simple manner. The indicator device and/or the control device can also be completely or partially embedded between the at least two preferably flat layers.
According to a preferred embodiment of the invention, the mat is configured to be slip-resistant on its underside and/or upper side and/or to be printable or printed on its upper side. For example, the underside of the mat can be configured with a slip-resistant coating and/or be roughened so that secure positioning on the patient's chest is ensured even when the mat is soiled, for example with sweat or blood. The upper side of the mat is also preferably provided with a slip-resistant coating and/or is roughened in order to allow secure placement of one or two hands of the user and ensure that the compressive force is securely exerted even if the upper side of the mat is soiled or wet. For example, instructions for performing cardiopulmonary resuscitation or cardiac massage may be printed on the upper side of the mat. Markings that make it easier to determine correct positioning of the force transmission unit and/or to achieve such positioning in patients of different body sizes can also be printed on the mat. For example, the mat may have different printed markings showing positioning thereof in children and adults. This facilitates use of the apparatus by medical lay persons and in stressful situations in particular.
In a further advantageous configuration, the apparatus can comprise a further flexible layer, which for example is composed of film or fabric and can be placed over the face of the patient when the apparatus is correctly positioned so as to provide facial protection or a protective mask for ventilation of the patient. For example, the further layer can be glued or reversibly attached by its edge to an edge area of the mat that rests on the upper area of the chest and may be placed over the patient's face. The further layer can have a form and/or markings that can provide additional assistance in aligning the apparatus on the patient's chest. This allows hygiene and safety during ventilation as a supplement to cardiac massage to be improved.
According to a preferred embodiment of the invention, the mat is configured to be foldable. For example, the mat as a whole can be flexible to a sufficient degree that a section of the mat can be placed by folding over another section. It is particularly preferred for the mat to have multiple, e.g. three sections connected to one another via predetermined fold lines. This can make it possible for the mat to be foldable, wherein the plurality of sections of the mat can be folded atop one other, lying flat in this state, and can then be correspondingly unfolded. Each of the sections of the mat can have a thickness that is essentially uniform but can optionally differ among the sections. In particular, the sections connected to one another via fold lines can themselves show higher stiffness, while the mat has lower stiffness at the fold lines and is bendable with a correspondingly smaller radius. The fold lines can e.g. be configured as fold grooves and can for example be produced by reducing the material strength of a mat that is otherwise configured with the same material strength throughout by stamping or milling in narrow linear areas of said mat; for example, the fold lines can also be configured as film hinges. A mat that is foldable in this manner will also be referred to as in the following as “foldable.” If the mat has three sections connected to one another that run essentially parallel to one another, these sections can be superposed so that two or three sections respectively lie on top of one another when the apparatus is closed. For example, the mat can be configured so as to be essentially rectangular and have two fold lines running parallel to each other and parallel to two opposite edges that divide the surface of the mat into three sections of approximately equal size; when the mat is then folded up, this gives rise to an arrangement in which each of the two lateral sections overlaps the middle section. The force transmission unit can be embedded in a section of the mat, and the control and/or indicator device can be embedded in one or a plurality of other sections. As the mat is configured to be foldable or have closeable flaps, storage, packaging, transportation, and carrying of the apparatus, e.g. in a motor vehicle, can be facilitated. In particular, in a configuration that is foldable or has closeable flaps, the mat can be dimensioned such that it has the format of a motor vehicle first aid kit according to DIN 13157 and fits into such a kit in this form; for application, the mat can be unfolded or opened in two simple working steps. An apparatus configured in this manner can easily be included in such a first aid kit so that it can be immediately and simply accessed in case of an accident.
It is also preferable for the control device to have a sleep mode and a working mode, wherein in sleep mode, the energy consumption of the control device is minimized and the force sensor and indicator device in particular are not operated, while in working mode, essentially all of the functions of the apparatus are activated. According to this embodiment of the invention, it is further provided that the apparatus comprises sensor means that generate signals based on which the control device is automatically switched from sleep mode to working mode when the mat is unfolded or opened. The sensor means may be configured e.g. as a magnetic sensor or a contact sensor. In particular, two interacting sensor elements can be arranged on two sections of the mat that are on top of each other when the mat is folded up; the sensor elements rest against each other when the mat is folded up, causing the sleep mode of the control device to be maintained, and are separated from each other when the mat is unfolded, causing the control device to be switched from sleep mode to working mode. This provides a simple and safe way to ensure that the apparatus according to the invention remains functional over a lengthy period, preferably for several years, and at the time of use is immediately ready for providing assistance during cardiopulmonary resuscitation without requiring any additional measures. Alternatively, the apparatus can have a switch which, when activated, turns on the control device or switches from sleep mode to working mode.
The control device is preferably configured such that the apparatus can be used only once. For this purpose, for example, one can set a time period during which, after the last exertion of a compressive force or after the control device is switched from sleep mode to working mode, no more compressive force has been exerted, and after a preset maximum duration of such inactivity is reached, the indicator device is permanently deactivated. The preset maximum duration of inactivity is thus selected such that one can be certain that an initiated resuscitation is ended, for example 15 minutes or one hour. This makes it possible with greater reliability to prevent an apparatus that has been used and is no longer fully functional, for example due to energy consumption, or no longer sufficiently meets hygiene requirements from being used again.
Alternatively or additionally, a seal can be applied to the apparatus or packaging of the apparatus that must be broken when the apparatus is unpacked or unfolded and thus indicates whether the apparatus has previously been used.
The control device is preferably configured such that the indicator device is activated depending on a detected maximum force exerted on the force transmission unit, a minimum force, a difference between the maximum and the minimum force, and/or the frequency of fluctuations in the detected force. In particular, the control device can be configured to continuously detect the compressive force exerted on the force transmission unit by receiving and processing a sensor signal from the force sensor continuously or with a brief cycle time. Maximum and minimum values of the exerted force can be determined based on the course over time of the sensor signal or the force value determined therefrom, with these values allowing compressions to be identified. For example, one can determine a relative maximum value and a relative minimum value within a full period of a periodic signal, with the frequency of these values corresponding to a preset frequency of the contractions to be exerted in cardiac massage. Based on this, a force amplitude can be determined based on the difference between the maximum and the minimum values, with said frequency being preset. However, the frequency of the compressions actually performed can also be determined based on the course over time of the sensor signal. In particular, the indicator device for generating a signal can be configured differently depending on the maximum detected force, the minimum force, the force amplitude, and/or the frequency of fluctuations in the force or the compressions, for example by generating sounds of different loudness and/or different pitch or optical signals of different brightness and/or colors; preferably, a plurality of signals that are of this type but perceptible via different sensory channels can be generated simultaneously. For this purpose, the indicator device can comprise a suitable sound generator and/or a suitable light source. For example, a suitable light source can be composed of a plurality of LEDs of different colors, such as red, green, and blue. This allows the user to obtain feedback during cardiac massage on the compressive force he/she exerts, the relaxation time between two compressions, and as to whether he/she is performing compressions with sufficient frequency.
It is also preferable for the control device to be configured such that the detected value of the compressive force exerted on the force transmission unit is compared with one or a plurality of predetermined target values and the indicator device is activated depending on conformity of the maximum force of a compression, the minimum force of a compression, the force amplitude, and/or the frequency of compressions with one or a plurality of target values or target ranges. Moreover, the control device can comprise first storage means in which preset target values and/or target ranges for the maximum force of a compression, the minimum force of a compression, the force amplitude, and/or the frequency of successive compressions are stored, with said values and/or ranges being accessible for conducting comparisons with the relevant values detected or determined based on the sensor signal. In particular, the control device can thus be configured such that based on the signal emitted by the indicator device, one can determine whether or not the compressions performed by a user are in conformity with target ranges for cardiac massage with respect to strength, amplitude, and/or frequency. In particular, the signal of the indicator device can be configured such that the direction of a deviation can be recognized based thereon so that a user can determine whether he/she should increase or decrease the maximum force, the amplitude of the compressions, and/or the frequency of the compressions in order to perform optimum cardiac massage. This can improve the safety of cardiac massage, even when performed by a medical lay person. Furthermore, because the preset target values and/or target ranges are stored, it is easy to adapt the apparatus according to the invention to conform to the prevailing requirements for different patient groups. For example, storage of corresponding target values makes it possible to optimize an apparatus according to the invention for the cardiopulmonary resuscitation of children or adults during production thereof without requiring any further modifications. By combining a plurality of apparatuses according to the invention having different sets of respective target values stored in their first storage means, it is therefore possible to provide a set of apparatuses for assisting users in cardiopulmonary resuscitation that is suitable for various uses.
It can further be provided that the control device is configured to emit a signal indicating the need for ventilation of the patient in addition to cardiac massage or alternating therewith. For example, it can be provided that a signal is generated after a preset time, after a preset number of compressions, or after a time depending on the amplitude of the compressions or the number of compressions that indicates the need for ventilation. In this way, the efficacy of cardiopulmonary resuscitation can be further improved.
The apparatus according to the invention is preferably equipped with an autonomous energy supply, particularly an electrical energy storage device, for example a battery or an accumulator. This makes it possible to ensure in a simple manner that the apparatus is immediately functional when needed, and in particular that the force sensor, the indicator device, and the control device are supplied with sufficient electrical energy.
According to a preferred embodiment of the invention, which is also claimed independently of the characterizing feature of claim 1, the control device comprises second storage means and is configured such that data are stored in the second storage means that indicate the detected values for the force exerted on the force transmission unit and/or its course over time; in other respects, the apparatus may be configured as described above. The second storage means can be configured with the first storage means as a single storage device. In particular, it can be advantageous to store the time elapsed from the first detected exertion of force after the apparatus is switched on or after the working mode begins, maximum values for the compressive force of the individual detected compressions, the force amplitude of the detected compressions, and the number and/or frequency of said compressions. Alternatively, it can be provided that the entire course of the sensor signal generated by the force sensor or the detected force values is stored. The stored data can be available for subsequent evaluation and can serve as a basis for decisions on further measures, for example with respect to further care following a successful resuscitation. The data can also make it possible to draw conclusions as to the effect of the cardiac massage performed, which for example can improve the learning effect of training in cardiopulmonary resuscitation with an apparatus according to the invention.
In a particularly advantageous configuration, the second storage means can be read via wire and/or wirelessly, so that the data stored therein are available for display, evaluation, and/or storage in a reading device. For example, the apparatus may comprise means for transmitting stored data by means of RFID technology, Bluetooth, or other wireless transmission paths. This makes it possible, for example, for medical personnel to immediately determine on arrival at the scene of an accident the type and effect of resuscitation measures carried out by a lay person, and based thereon, to take further measures, in particular relating to cardiac massage and/or ventilation.
Alternatively or additionally, at least some of the stored data may be representable on the indicator device. For example, the control device can be configured such that, in response to an input signal that can be input by means of a switch or in the event of an interruption in the force exerted on the force transmission unit, it activates the indicator device to generate a signal that makes important stored data identifiable. As an example, the number of repetitions of a brief acoustic or optical signal or the number of activated LEDs can indicate the number of minutes elapsed since the onset of working mode or a first detected exertion of force or the number of minutes during which fluctuating exertion of sufficiently strong force is detected by the force transmission unit. In this way, indications as to the resuscitation measures performed that can serve as a basis for decisions regarding further measures can be obtained in a particularly simple manner.
In a method according to the invention for assisting a user during cardiopulmonary resuscitation of a patient, the control device of an apparatus configured as described above can automatically be switched from sleep mode to working mode when the mat is unfolded, a compressive force exerted on the force transmission unit can be detected by the force sensor of the force transmission device, the indicator device of the apparatus can be activated by the control device based on the detected force, and data on the detected force and/or its course over time can be stored in a storage unit of the control device. For example, the stored data can be the time elapsed since a first exertion of force of a first compression, the maximum force of each compression, and/or the frequency of the detected compressions. According to advantageous improvements of the method according to the invention, the indicator device is activated depending on a maximum force exerted on the force transmission unit, a minimum force exerted on the force transmission unit, a difference between the maximum and the minimum force, and/or the frequency of fluctuation in the force exerted on the force transmission unit, depending in particular on conformity with a respective target value or target range. In a further advantageous configuration, it can be provided that the storage device of the control device is read in a wire-based or wireless manner.
In particular, for use of the apparatus according to the invention, said apparatus is first removed from a package, in which the apparatus may be shrink-wrapped. If the package has a seal, this destroys said seal, so that one can recognize that the apparatus has been used. In a following step, the apparatus is opened by unfolding the sections of the mat that are folded onto one another. This generates a sensor signal that causes the control device of the apparatus to be automatically switched from sleep mode to working mode. The optical and acoustic indicators can then be immediately activated as soon as working mode has been achieved, or it may be necessary to press a power switch for this purpose. The apparatus is placed on the chest of a patient and aligned by means of the markings printed on the upper side of the mat or provided by the shape of the mat. In this manner, one can ensure that a compression area marked on the upper side of the apparatus comes to rest over the area of the patient's chest on which the compressive force must be exerted in cardiac massage. The force transmission unit is embedded in the mat at the site where the corresponding area is marked on the upper side. As soon as the user exerts a compressive force on this area, this is detected by the force sensor of the force transmission unit, and the sensor signal is evaluated by the control device of the apparatus. If the preset target force for cardiac massage is not reached, this can be indicated by a corresponding sound or a colored optical signal, such as a red optical signal. If the exerted force is in the target range, this can be indicated by a green light. The force amplitude of a compression can also be measured and compared with a target range, and a corresponding signal can be transmitted to the user. Moreover, the target frequency of the compressions to be performed can be specified by a further light or sound, or the actual frequency of the exerted compressions can be measured, and this can generate a signal that makes it possible to determine whether the frequency is too low, within a target range, or too high. After a preset number of compressions, a signal can be generated that indicates that ventilation is needed. The cardiac massage is continued after this. Storage and reading of the detected force values, particularly the course over time of the exerted compressive force, can be advantageous in supporting a decision regarding the further care of the patient after use of the apparatus according to the invention is completed.
It is to be understood that the features mentioned above and to be explained below can be used not only in the respective combination given, but also in other combinations or alone, without departing from the scope of the present invention.
Further aspects of the invention are explained in the following description of two preferred embodiments and the attached drawing. The figures show the following:
As shown schematically in
The sections 5, 6, 7 can be placed on top of one another by folding them up along the fold lines 3, 4. In
The force transmission unit 10 is configured approximately in the form of a circular disk overall having a diameter D of approximately 5 to 12 cm (see
The force sensor 13, which for example can be a piezoelectric or a resistive force sensor, has e.g. a measuring range of 0.1 to 300 N and a thickness of approximately 0.1 to 2.5 mm, for example 0.45 mm. The force sensor 13 has e.g. a square surface with a side length of approx. 4 cm and has an accuracy of ±3%, an operating temperature range of −30 to +70° C., a response time of approx. 5 μs, and a useful life of approximately one million compression cycles, which is generally sufficient for the present application.
As can be further seen in
In
In
As shown in
For use, the apparatus 1 is removed from a package in which it is sealed in a folded or closed state (see
As symbolically shown in
For purposes of clarity, not all of the reference symbols are shown in all of the figures. Reference symbols in a figure that are not explained have the same meaning as in the remaining figures.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2015 006 540.8 | May 2015 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2016/000851 | 5/23/2016 | WO | 00 |
