• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The invention relates to a medical respiratory assistance device for supplying a respiratory gas, such as air, enriched or not with oxygen, to a patient during a cardiopulmonary resuscitation (CPR) comprising a source (1) of breathing gas , such as a micro-blower, for supplying a respiratory gas to said patient during cardiopulmonary resuscitation (CPR), means for measuring CO2 content (4), signal processing and control means (5) and at least a graphical user interface (7). According to the invention, the signal processing and control means (5) are configured to process the CO2 content measurement signals, select the maximum value (Vmax) of CO2 content for a given period of time (dt) , and transmit this maximum value (Vmax) to the graphical user interface (7), which displays this maximum value (Vmax) of CO2 content.
    公开号:FR3076462A1
    申请号:FR1850224
    申请日:2018-01-11
    公开日:2019-07-12
    发明作者:Marceau RIGOLLOT；Jean-Christophe Richard；Bilal Badat
    申请人:Air Liquide Medical Systems SA；
    IPC主号:
    专利说明:

    Provided is a respiratory support apparatus, i.e. a medical ventilator, for supplying respiratory gas to a patient receiving cardiopulmonary resuscitation (CPR), i.e. a patient on arrest cardiac subject to cardiac massage with alternating chest compressions and relaxations, with display of the maximum value of CO2 content measured during a given period of time.
    Mechanical ventilation medical devices, also called respiratory assistance devices or medical ventilators, are commonly used to supply respiratory gas, for example air enriched or not with oxygen, to certain patients suffering from respiratory disorders.
    The supply of respiratory gas to the patient is commonly operated by means of a motorized and controlled micro-blower, as in particular described by EP-A-3093498, EP-A-2947328, EP-A-2986856, EP-A-2954213 or EP-A-2102504.
    It is known to monitor the gaseous compounds present in the gas administered to patients, in particular in the gases exhaled by patients which contain CO2 resulting from pulmonary gas exchanges, that is to say CO2 produced by the patient's metabolism. , transported to the lungs through the bloodstream and then evacuated when the patient expires. Thus, the etCCh for End Tidal CO2 or CO2 at the end of expiration, corresponds to the measurement of the fraction of CO2 exhaled in the gases collected during the expiration of an individual, whether his inspiration is natural or assisted c ' that is to say, obtained by mechanical ventilation.
    Under mechanical ventilation, different techniques allow spectrophotometric analysis of the CO2 fraction of exhaled gases. To do this, the gas present in the expiratory circuit can be: - either aspirated and then analyzed by an analysis cell at a site remote from the respiratory circuit. This way of operating is called derivative or secondary flow, i.e. "sidestream" in English, - or analyzed near the patient, preferably at the level of a part Y arranged in the respiratory circuit near the patient. This way of operating is called main stream, i.e. "mainstream" in English.
    During cardiopulmonary resuscitation or CPR performed on a person in cardiopulmonary arrest, with the implementation of a cardiac massage, alveolar CO2, which depends not only on pulmonary ventilation / perfusion ratios but also on the amount of CO2 generated by cellular metabolism, represents a very useful parameter for the rescuer, for example a doctor, to judge the effectiveness of CPR.
    In theory, the more effective the CPR, the greater the cardiac output generated by chest compressions, the greater the amount of CO2 brought back to the lungs.
    Monitoring of etCCh, which indirectly reflects the alveolar CO2, is increasingly used to monitor CPR in a non-invasive way, that is to say to inform the rescuer while he performs cardiac massage, ie , alternating chest compressions (CT) and relaxation.
    Figure 1 is a capnogram which is a graphical representation of the changes in CO2 content in a patient's breathing gas over time (in seconds). This type of capnogram is observed on patients ventilated outside of cardiac arrest situations. As we can see, it is divided into four successive phases: - Phase I: it represents the inspiratory baseline which must be stable at zero. - Phase II: it is the ascending part of the capnogram and corresponds to the appearance of CO2 in the exhaled gases, at the beginning of the patient's exhalation, by emptying the best ventilated alveoli. In reality, the expiration begins a little before this phase because the gas exhaled at the beginning of expiration is devoid of CO2 since it did not participate in gas exchanges, due to the instrumental and anatomical dead spaces. The increase in CO2 is slower the more the lungs are inhomogeneous and the alveoli have long time constants. - Phase III: it corresponds to the alveolar plateau phase which corresponds to the gas rich in CO2 coming from the least well ventilated alveoli. The maximum end of plateau value (PetCO2) corresponds to the value of etCCk. - Phase IV: it corresponds to the decrease in the CO2 concentration caused by the start of spontaneous or assisted inspiration (i.e. mechanical).
    However, during Cardiopulmonary Resuscitation (CPR) on a patient in cardiopulmonary arrest, the capnogram is very different for several reasons, in particular:
    Chest compressions generate displacements of small volumes of gas. These volumes, however close to the instrumental and anatomical dead space, disturb the capnogram between two ventilatory cycles. Oscillating traces are thus often observed, the maximum value of CO2 on each thoracic compression (CT) constantly changing.
    The ventilation / perfusion ratios which reflect respiratory physiology are very strongly modified. In addition, small sections of gas mobilized by chest compressions can pass several times in front of the sensor. The maximum concentration observed, during each chest compression (CT), is therefore often far from the true alveolar concentration.
    Dynamic behaviors of opening and closing small airways during CPR have been reported. This phenomenon compromises gas exchange and therefore the interpretation of CO2 concentrations during CPR.
    It is therefore understood that the etCO2 as it is currently measured, that is to say during each thoracic compression (CT), does not make it possible to obtain a reliable approximation of the alveolar CO2, while this alveolar CO2 is important because it may reflect the quality of CPR and a possible resumption of spontaneous cardiac activity (RACS).
    The recurring problem that results is that a measurement of CO2 without taking into account all or some of these factors, in particular the impact of the ventilation performed on the patient in cardiac arrest and the variability of the CO2 signal between two machine cycles, makes the use of this CO2 measurement unreliable, even unusable.
    Current etCO2 monitoring solutions are adapted to variations in CO2 caused by breathing, whether mechanical or spontaneous. The frequencies involved are of the order of 10 to 40 c / min. The algorithms and mechanisms used are adapted to these frequencies and to small variations in CO2 between two patient breaths. As such, we can cite the documents WO-A-14072981, US-A-2016/133160 and US-A-2012/016279, which propose methods for monitoring the CO2 content in the gases exhaled by a patient undergoing a CPR, in which the ventilators indicate to the rescuer that he must stop the cardiac massage when the content of etCÜ2 is greater than 30 mm Hg for example.
    However, during cardiopulmonary resuscitation, the frequencies of the chest compressions (CTs) involved are close to 100 c / min, the volumes of gas mobilized low and the gas flows large and irregular. In addition, the dead space problem mentioned above adds to these difficulties since, due to the CTs, the same fraction of gas can be analyzed several times by the CO2 sensor, failing to set up a flushing or purge of dead space.
    Under these conditions, the value of etCO2 displayed by the current ventilators is refreshed at an inadequate frequency since they try to follow the evolution of CO2 at the frequency of the massage, namely 100 c / min. In other words, the values of etCÜ2 displayed by current ventilators are not representative of a CO2 concentration linked to the patient's metabolism because the origin of the gas analyzed is not guaranteed. In other words, the measured values are often erroneous because they do not reflect, or only very badly, the concentration of alveolar CO2.
    The problem which then arises is to propose an improved respiratory assistance device, that is to say a medical ventilator, which makes it possible to display, during a CPR implementing the respiratory assistance device, a reliable CO2 value, that is to say that reflects alveolar CO2 as much as possible, in order to better assist the rescuer during CPR by offering him relevant information facilitating CPR monitoring, such as detection of a RACS for example.
    The solution of the invention therefore relates to a respiratory assistance device, that is to say a medical ventilator, for supplying respiratory gas, such as oxygen, to a patient during cardiopulmonary resuscitation (CPR). comprising: - a source of respiratory gas for supplying respiratory gas to said patient during cardiopulmonary resuscitation (CPR), - means for measuring CO2 content for carrying out measurements of concentration of CO2 produced by the patient, and providing CO2 content measurement signals to signal processing and control means, signal processing and control means configured to process the CO2 content measurement signals coming from the CO2 content measurement means, - at least one graphical user interface (IGU), characterized in that: - the signal processing and control means are configured to: a) process the CO2 content measurement signals corresponding to op measurements by the means for measuring the CO2 content for a given period of time (dt), and extracting a plurality of CO2 content values therefrom, b) selecting the maximum value (Vmax) of CO2 content from the plurality of values of CO2 content measured during said given period of time (dt), and c) transmitting said maximum value (Vmax) of CO2 content to the graphical user interface, - and the graphical user interface is configured to display the maximum value (Vmax) of CO2 content.
    Depending on the case, the respiratory assistance device of the invention may include one or more of the following technical characteristics: - the IGU is configured to display at least one value of CO2 content supplied by the processing means signal and steering. - the CO2 produced by the patient. This CO2 is observable during the patient's expiration and / or be rebreathed on the next inspiration, in particular when it is gas trapped between a part Y and the CO2 sensor for example. - The source of respiratory gas is in fluid communication with a gas pipe. - The source of respiratory gas is a source of air, in particular a motorized micro-blower, also called turbine or compressor. the means for measuring the CO2 content are arranged so as to carry out measurements of the CO2 concentration downstream of the gas pipe. the means for measuring the CO2 content are electrically connected to the signal processing and control means. - the source of respiratory gas is in fluid communication with a gas conduit serving to convey the respiratory gas towards the patient, i.e. up to a respiratory interface. - The signal processing and control means comprise at least one electronic card or the like. - The signal processing and control means comprise at least one microprocessor, preferably a microcontroller. - the microprocessor implements at least one algorithm. - the CO2 content measurement means are arranged on the main gas flow, that is to say that they are in a 'mainstream' type arrangement (i.e. main flow). the means for measuring the CO2 content comprise a capnometer. - the CO2 content measurement means are arranged so as to carry out CO2 concentration measurements downstream of the gas pipe, preferably at a downstream end of the gas pipe, - the gas pipe is in communication fluidic with a respiratory interface, also called patient interface. - the respiratory interface is an endotracheal intubation probe, a facial mask or a laryngeal mask, also called a supra-glottic device, or any suitable device for administering gas. - The respiratory interface is preferably an endotracheal intubation probe, commonly called a 'tracheal probe'. the means for measuring the CO2 content are upstream and in the immediate vicinity of the respiratory interface, that is to say close to the mouth of the patient. - According to a first embodiment, the means for measuring the CO2 content are arranged on a junction piece arranged upstream of the respiratory interface, preferably between the respiratory interface and the downstream end of the gas conduit, particular between the respiratory interface and a Y-piece with internal gas passages. - Preferably, the means for measuring the CO2 content are arranged on a junction piece comprising an internal gas passage. - According to a second embodiment, the means for measuring the CO2 content are arranged in the device, that is to say in the carcass of the device, by being connected, via a gas sampling pipe or similar to a gas sampling site located upstream and in the immediate vicinity of the respiratory interface. in particular, the means for measuring the CO2 content are fluidly connected to a gas sampling site carried by a junction piece, in particular arranged between the respiratory interface and the gas conduit, typically between the respiratory interface and a downstream end of said gas pipe. - The junction piece is fluidly connected between the intermediate connecting piece, that is to say a Y-piece, and the respiratory interface, typically a tracheal tube or a mask. - the inspiratory branch, the expiratory branch and the respiratory interface are in fluid communication with each other. - It includes a patient circuit comprising an inspiratory branch allowing gas to be conveyed to the patient. - The patient circuit further includes an expiratory branch for evacuating the gas exhaled by the patient. - the inspiratory branch, the expiratory branch and the patient interface are fluidly and / or mechanically connected, directly or indirectly, to the intermediate connection piece, in particular a Y-piece. - the means for measuring the CO2 content are arranged so as to carry out CO2 concentration measurements at the inlet of the expiratory branch or at the outlet of the inspiratory branch of the gas circuit. - The expiratory branch communicates fluidically with the atmosphere to evacuate all or part of the gas exhaled by the patient, in particular the gas rich in CO2. - the inspiratory branch and / or the expiratory branch include flexible tubes. - Preferably, all or part of the gas pipe forming all or part of the inspiratory branch of the gas circuit is a flexible pipe. - The signal processing and control means are configured to control the source of respiratory gas and deliver the respiratory gas according to successive ventilation cycles. - each ventilatory cycle includes a BP phase (Dbp) during which the gas is delivered by the micro-blower at a pressure called low or low pressure (BP), and an HP phase (Dhp) during which the gas is delivered by the micro -blower at a pressure called high or high pressure (HP), with HP> BP. - The micro-blower is controlled to supply gas at a low pressure (BP) between 0 and 20 cm of water, preferably between 0 and 15 cm of water, more preferably 0 and 10 cm of water. - the micro-blower is controlled to supply gas at a high pressure (HP) between 5 and 60 cm of water, preferably between 5 and 45 cm of water, preferably still 5 and 30 cm of water (with HP> BP). - the BP phase has a duration greater than the HP phase. - the BP phase has a duration of between 2 and 10 seconds, typically of the order of 3 to 6 seconds. - The HP phase has a duration of between 0.5 and 3 seconds, typically of the order of 1 to 2 seconds. - the given period of time (dt) is several seconds. - the time period (dt) is between 2 and 10 seconds, typically of the order of 3 to 6 seconds. - the period of time (dt) corresponds to the duration of the BP phase of each ventilatory cycle. - the total duration of a ventilatory cycle is between 3 and 10 seconds. - the period of time (dt) given includes several durations of chest compressions and successive relaxations, typically between 5 and 12 chest compressions. - the CO2 content measurement means are configured to operate continuous measurements. - The CO2 content measurement means include a CO2 sensor. - The CO2 content measurement means comprise a CO2 sensor, the measurement of which is in fluid communication with the interior or lumen of the junction piece arranged upstream of the respiratory interface. - It includes storage means cooperating with the signal processing and control means for storing the plurality of CO2 content values measured during the given time period. - the storage means are further configured to store the maximum values (Vmax) of successive CO2 content, that is to say measured during successive periods of time (dt) given. - The storage means include a flash memory or hard drive type. - It further comprises gas flow measurement means configured to operate at least one measurement, preferably continuously, of the flow of expired gas and / or the flow of gas inspired and or exhaled by the patient. The flow allows monitoring and surveillance of chest compressions, as well as calculation, monitoring and surveillance of the volumes of gas delivered and exhaled (ventilator and CTs). - The gas flow measurement means comprise a flow sensor. - the graphical user interface (IGU) includes a digital screen, preferably a touch screen. - the graphical user interface is configured to display the maximum value (Vmax) of CO2 content in the form of a numerical value or a graphical representation displayed on the IGU, or both. - the graphical user interface is configured to display several successive maximum CO2 content values (Vmax) in the form of a graphical representation. - the graphical user interface is configured to display one or more maximum values (Vmax) of CO2 content in the form of a graphical representation of the curve, bar graph or other type. - the screen includes several keys activating different functions and / or several zones or display windows. - the screen is of the type with color display. - alternatively, the screen is of the type with black and white display or else allows a change from a color display to a black and white display so as to effect energy savings. - It comprises a source of electric current, for example a battery or the like, preferably a rechargeable battery. - It includes alarm means configured to go off when the maximum value of CO2 content exceeds a threshold value. the alarm means include an audible or visual alarm, or both. - the alarm means are programmed to be triggered when the maximum value (Vmax) of CO2 measured, at an instant t, is such that: [VmaxCCk]> n x [MoyCCk], where:. n is between 1.25 and 4, preferably between 1.5 and 3, for example of the order of 2. [VmaxCCk] is the maximum value of CO2 content measured during a given time dt, for example over a time dt between 2 and 10 seconds,. [MoyCCL] is the average value of the maximum values of CO2 content [VmaxCCL] determined for several successive durations dt included in a given time window (FT) (FT> x.dt with x> 2), for example a period of 30 sec to 5 minutes, or more. - It comprises a rigid carcass comprising the source of respiratory gas, the signal processing and control means, the source of electric current and the storage means. - The rigid carcass is formed in whole or in part from polymer. - the graphical interface is arranged in one of the walls forming the fan casing. - The CO2 content measurement means are configured to operate successive CO2 concentration measurements over successive periods of time (dt), that is to say periods of time (dt) spaced from each other. - The CO2 content measurement means are configured to operate successive CO2 concentration measurements over successive periods of time (dt) during successive ventilation cycles, in particular during the BP phases of successive ventilation cycles. The invention also relates to a method (ie, a method) for monitoring cardiopulmonary resuscitation (CPR) operated on a patient in cardiac arrest, in which: - a respiratory assistance device comprising a source is used (1) respiratory gas, such as a micro-blower, for supplying respiratory gas to a patient during cardiopulmonary resuscitation (CPR), - measurements of the concentration of CO2 produced by said patient are carried out, for example by means of a capnometer, - the CO2 content measurement signals are processed, for example by means of signal processing and control means (5), such as a microprocessor, - a plurality of CO2 content values measured during a given period of time (dt), - the maximum value (Vmax) of CO2 content is selected from the plurality of values of CO2 content, and - the maximum value (Vmax) of CO2 content is displayed during the period given time (dt), over a IGU. The invention will now be better understood thanks to the following detailed description, given by way of illustration but not limitation, with reference to the appended figures in which: - Figure 1 is a graphic representation of the variations in CO2 content in the respiratory gases d a patient ventilated outside a cardiac arrest situation, - Figure 2 shows a ventilatory cycle with two pressure levels that can be implemented by the device of Figure 6 to ventilate a patient in cardiopulmonary arrest during a CPR, - Figure 3 illustrates the pressure variations observed by the machine at the end of the respiratory circuit in a patient with cardiopulmonary arrest during CPR, - Figure 4 shows schematically the amount of CO2 measured by the capnometer of the apparatus of Figure 6 before and after return to spontaneous cardiac activity, - Figure 5 shows diagrammatically the peaks of CO2 content during the ventilatory cycles m is implemented during CPR, and FIG. 6 is a diagram of an embodiment of a respiratory assistance device for CPR according to the invention,
    FIG. 6 is a schematic representation of an embodiment of a respiratory assistance device or medical ventilator according to the invention used to supply a respiratory gas, typically air or air enriched with oxygen, to a patient P during cardiopulmonary resuscitation (CPR), that is to say a person in cardiac arrest on whom a rescuer performs a cardiac massage, that is to say alternating chest compressions (CT) and loosening (Re), that is, non-chest compressions.
    This apparatus or ventilator comprises a source 1 of respiratory gas, such as a motorized micro-blower, which is in fluid communication with a gas conduit 2 to supply respiratory gas to said patient P during cardiopulmonary resuscitation, typically of the pressurized air.
    The source 1 of respiratory gas is controlled, that is to say controlled, by signal processing and control means 5, in particular an electronic microprocessor card 6 or the like. The signal processing and control means 5 control the source 1 of respiratory gas so that it delivers the gas according to one (or more) predefined ventilation mode.
    Preferably, the signal processing and control means 5 make it possible to control the gas source 1 to deliver the gas according to a "normal" ventilatory mode corresponding to ventilation of a patient who is not in cardiac arrest and a “CPR” ventilation mode corresponding to ventilation of a patient who is in cardiac arrest and on whom a rescuer starts or performs CPR.
    For example, according to a ventilation mode dedicated to CPR, the source 1 of respiratory gas is controlled to supply the respiratory gas, typically air, according to a ventilation cycle comprising several pressure levels or of “BiPAP” type, such as illustrated in Figure 2, in particular 2 pressure levels comprising a low pressure level, for example a low pressure (BP) of between approximately 0 cm H2O and 15 cm H2O, and a high pressure level, for example a high pressure ( HP) between approximately 7 cm H2O and 40 cm H2O.
    The gas is delivered alternately between these two pressure levels (BP, HP), as illustrated in Figure 2, throughout the CPR by the rescuer, that is to say while the rescuer operates the CTs and relaxations. The duration (Dbp) of supply of gas at low pressure (BP) by the micro-blower 1 is between 2 and 10 seconds, typically of the order of 3 to 6 seconds, while the duration (Dhp) of supply of the high pressure gas (HP) is less than 3 seconds, for example of the order of 0.5 to 1.5 seconds.
    The micro-blower 1 of the fan generates two pressure levels, namely a high pressure level (i.e. PH) and a low pressure level (i.e. PB). The cardiac massage alternating phase of chest compressions (CTs) and relaxations (Re) generates pressure peaks which are superimposed on the fan pressure cycles. This results at the level of the patient interface, a pressure curve as illustrated in Figure 3 where the pressure peaks at the level of the high (ie at PH) and low (ie at BP) plates reflect the chest compressions (CT) with pressure increase since the chest collapses under the pressure of the CT operated by the rescuer, and the releases (Re) with pressure drop since the chest rises in the absence of CT.
    As can be seen in Figures 2 and 3, in the context of the present invention, the given period of time (dt), during which the plurality of CO2 content values is measured and the maximum content value (Vmax) in CO2 is extracted corresponds to the duration (Dbp) of supply of the gas at low pressure (BP), ie between 2 and 10 seconds, typically between 3 and 6 seconds.
    The gas supplied by the micro-blower 1 is conveyed by the gas conduit 2 which forms all or part of the inspiratory branch 2a of the patient circuit 2a, 2b. The respiratory gas, generally air, is supplied to the patient via a gas distribution interface 3, namely here an endotracheal intubation probe, more simply called the 'tracheal probe'. However, other interfaces can be used, in particular a facial mask or a laryngeal mask.
    The gas conduit 2 is in fluid communication with the gas distribution interface 3, such as a tracheal tube, so as to supply it with the gas coming from the source 1 of respiratory gas, namely here a micro-blower. The gas pipe 2 is in fact connected to the tracheal tube 3 by means of an intermediate connection piece 8, namely here a Y-piece. This intermediate connection piece 8 in Y includes internal gas passages .
    The intermediate connection piece 8, that is to say here the Y-piece, is also connected to the expiratory branch 2b of the patient circuit 2a, 2b so as to be able to collect and convey the gases rich in CO2 exhaled by the patient. P and evacuate them to the atmosphere (in 9).
    According to the invention, there are also provided means for measuring the CO2 content 4, called the CO2 sensor or capnometer, designed to carry out measurements of the concentration of CO2 in the gas exhaled by the patient P, and provide measurement signals. of CO2 content to the signal processing and control means 5 where these measurement signals can be processed, in particular by a (or) calculation algorithm or the like.
    In the embodiment of FIG. 6, the CO2 sensor is arranged near the mouth of patient P in the “main stream” configuration, that is to say upstream and in the immediate vicinity of the interface respiratory 3, preferably between the intermediate connection piece 8, ie the Y-piece, and the respiratory interface 3, ie the tracheal tube, for example on a junction piece 18 (cf. FIG. 6).
    According to another embodiment (not shown), the CO2 sensor can be arranged in a “derivative flow” configuration (sidestream). In this case, the CO2 sensor 4 is located in the carcass of the respiratory assistance device and is connected, via a gas sampling line, such as a tube or the like, to a gas sampling site located upstream. and in the immediate vicinity of the respiratory interface 3, for example on the junction piece 18. This gas sampling line communicates fluidly with the lumen of the junction piece 18 so as to be able to take gas there and then convey it to the CO2 sensor located in the casing of the device.
    In all cases, the junction piece 18 includes an internal gas passage allowing the gas to pass through it.
    Preferably, the CO2 sensor operates continuous measurements of the CO2 concentration in the gas circulating through the junction piece 18, which gas is enriched in CO2 during its passage through the lungs of patient P where gas exchanges.
    The CO2 content measurement signals are then transmitted by the CO2 sensor, by electrical connection or the like, in particular wired or other, to the signal processing and control means 5.
    Indeed, the monitoring of the CO2 content, in particular of etCO2 which indirectly reflects the alveolar CO2, is of great importance during CPR, in particular to detect an RACS. Indeed, a return of spontaneous cardiac activity (RACS), therefore a significant increase in cardiac output, generates a rapid increase in the amount of CO2 brought by the blood to the lungs and transferred through the alveolocapillary membrane, this CO2 then being found in the gas flow exhaled by the patient.
    The signal processing and control means 5 are configured (in particular the microprocessor 6) to: a) process the CO2 content measurement signals which correspond to measurements carried out by the CO2 content measurement means 4, typically the CO2 capnometer or sensor, during the given period of time (dt), for example a few seconds, to extract a plurality of CO2 content values therefrom, b) select the maximum value (Vmax) of CO2 content from said plurality of CO2 content values measured during said given time period (dt), and c) transmitting this maximum value (Vmax) of CO2 content to a graphical user interface 7 or IGU.
    A source of electric current 10, such as a rechargeable battery or the like, supplies, directly or indirectly, electric current to the signal processing and control means 5, the micro-blower 1, the IGU 7 and any other element of the device, in particular a memory 11. The source of electric current 10 is preferably arranged in the carcass of the fan. In general, the medical ventilator of the invention allows a continuous measurement of the CO2 concentration produced by the patient P, the measurement being carried out by the capnometer 4 which is arranged on the path of the gas, close to the mouth. of patient P, preferably here between the Y-shaped part 8 and the tracheal tube 3 of FIG. 6, that is to say at the level of the junction piece 18 fluidly connected between the Y-piece 8 and the probe 3.
    The fan also allows, if desired, to operate in parallel a continuous measurement of the flow rates of the exhaled and inspired gases, using one or more flow sensors (not shown).
    According to the invention, the IGU is configured for its part to display the maximum value (Vmax) of CO2 content supplied by the signal processing and control means 5 which is selected from several values of CO2 concentrations measured during a given duration corresponding to several chest contractions and successive releases of compression operated by a rescuer performing a cardiac massage (ie CPR) on patient P in a state of cardiac arrest.
    In fact, the value of CO2 concentration which most reflects the alveolar CO2 content, and therefore gives a good indication of the state of the blood circulation in patient P during CPR, is the highest value of CO2 , also called maximum value (Vmax) or peak value, as illustrated in Figure 5 which shows the evolution of the CO2 content in the gas and illustrates several measurements of etCCk measured during several successive durations dt, for example durations 3 to 6 seconds, while performing CPR. We can see that the CO2 content of the gas is not constant during a given time interval dt and that there is therefore necessarily a maximum value (Vmax) of CO2 content over each interval dt, i.e. say the peak value.
    From there, in the context of the present invention, the fan stores (in 11) therefore all the values of CO2 peaks during each time period dt, typically between 3 and 7 seconds, and determines the maximum value Vmax of CO2 content among the plurality of peaks (EtCO2_i, EtCO2_2, EtCO2_3, ..., EtCO2_x) measured over a given period of time (dt), as illustrated in Figure 5.
    During a CPR, the CO2 content in the gas produced by the patient, and passing in front of the measurement of the capnometer 4 varies depending on the presence or not of chest compressions (CT).
    Thus, after blowing air through the micro-blower 1 of the ventilator and as long as the CTs have not started, no CO2 is detected in the gas flow conveyed by the conduit 2 to the respiratory interface 3 which then distributes this air to the lungs of patient P.
    After a few chest compressions (CT) performed by a rescuer, CO2 is detected in room 8 in Y by the capnometer 4 since the alternation of CT and releases (Re) generate movements of air entering and leaving the lungs of patient P by "mimicking" the expiratory phases of patient P. Exhaled air rich in CO2 is then found in room 8 in Y and capnometer 4 (see Fig. 6) and measurements of concentrations in CO2 can be produced by the capnometer 4. The corresponding measurement signals are sent to the signal processing and control means 5 where they are processed as explained above, so as to determine the maximum value (Vmax) of CO2 on each time interval dt.
    The maximum value of CO2 (Vmax) is the one which best represents the alveolar CO2. Indeed, the CO2 present at the level of the part 8 in Y and of the capnometer 4 is "washed" little by little because of the successive and repeated chest compressions, and tends to decrease after reaching this maximum value since the CTs also generate l evacuation to the atmosphere (at 9) of gases rich in CO2, via the expiratory branch 2b of the patient circuit. Successive CTs therefore generate different levels of CO2, the most representative being the peak or maximum value (Vmax), as illustrated in Figure 5.
    In the context of the present invention, the ventilator stores (in 11) therefore all the maximum values (Vmax) of CO2 between two ventilatory cycles, that is to say during the successive dt durations, determines the maximum value (Vmax) of CO2 content among the plurality of maximum measured values, and displays this maximum value (Vmax) on the screen of the IGU 7.
    This maximum value (Vmax), during a given time interval dt, can be displayed as a single numerical value. It is also possible to display several maximum values (Vmax) measured successively over several successive time intervals (dt). Furthermore, if useful or desired, it is also possible to display it in the form of a graphical representation having several maximum values (Vmax) measured successively over several successive time intervals (dt) over time, for example on the Last 2 to 5 minutes, for example a graphical representation of the curve, bar graph, or other type.
    The data calculated from these CO2 measurements allow the rescuer to better "control" the CPR thanks to an indicator that reflects the state of the patient's circulation and metabolism since, at a constant level of ventilation, the more the CPR is effective, the greater the quantity of CO2 produced and transferred through the alveolo-capillary membrane and therefore the greater the quantity of CO2 that can be detected at the capnometer 4.
    From there, in case of return to spontaneous cardiac activity (RACS), the circulation resumes suddenly and therefore the quantity of alveolar CO2 increases in parallel, which induces a significant increase the quantity of CO2 perceived by the capnometer 4 by a factor often greater than 2, as illustrated in Figure 4. Indeed, we see in Figure 4 that the EtCCk is always less than 25 KPa during CPR, while the EtCCk increases suddenly until reaching more than 50 KPa during of RACS. This can be immediately detected by the rescuer who can then perform a rhythm analysis to stop the cardiac massage in the event of an effective RACS.
    In other words, within the framework of the invention, the fact of displaying on the IGU 7, the maximum value of EtCCfi, for a given period of time (dt), allows the rescuer to better detect the occurrence of the RACS since this maximum value (Vmax) of CO2 closely reflects the alveolar CO2.
    Indeed, it has been found, in the context of tests operated within the framework of the present invention, that continuously displaying all the CO2 measurements would not be effective because the cardiac massage even practiced on a regular basis (pressure force , frequency ...) inevitably generates significant variations in CO2 content at the capnometer, from one CT to another. This is explained by the dynamic behavior, of opening / closing of the small airways as well as by the effect of washing the dead space during successive chest compressions between two machine cycles. Therefore, displaying all the CO2 measurements could mislead the rescuer or even "drown" him with too much information and he could then sometimes "believe" in a RACS when it would only be a question of an artifact, or conversely, not noticing a RACS in the patient and continuing the massage while the patient is in the RACS phase. In all cases, the use of a single instantaneous value for the purpose of prognosis or choice of therapeutic strategy is made risky by the oscillating nature of the instantaneous etCO2 value, i.e. at each chest compression (CT).
    In the context of the invention, it has been shown by practical tests that these problems can be completely overcome by displaying only the highest value of CO2 content (Vmax) for a given period of time (dt), typically a few seconds.
    In addition, it has been observed that the CO2 content measured with each chest compression can vary enormously from one chest compression to another. This is due not only to the anatomical and instrumental dead space but also to the degree of opening of the patient's airways. Taking these factors into account, the maximum value (Vmax) of CO2 therefore appears to be a better reflection of alveolar CO2, and is therefore a good indicator of RACS (if it increases suddenly) or of new cardiac arrest (if it decreases suddenly) ), which immediately informs the rescuer and in a more relevant way.
    Thus, when the rescuer finds a sharp rise in the displayed CO2 value, the latter can conclude that the patient is in the RACS phase, as illustrated in FIG. 4, and can then decide to stop the cardiac massage in order to carry out a rhythm analysis for example.
    Advantageously, the ventilator of the invention can also include alarm means designed and programmed to warn the rescuer or the like when the maximum measured value of CO2 exceeds or, conversely, becomes lower than a given value, prefixed or calculated in continued.
    In particular, an audible and / or visual alarm is provided which is triggered when the maximum measured value of CO2, at an instant t, is greater than a threshold value, for example: [VmaxCCk]> 1.5 x [MoyCCk] where: [VmaxCCk] is the maximum value of CO2 content measured during a given time dt, for example over a time dt between 2 and 10 seconds,. [MoyCCk] is the average value of the maximum values of CO2 content [VmaxCCk] determined for several successive durations dt included in a given time window (FT) (FT> x.dt with x> 2), for example a period of 30 sec to 5 minutes, or more.
    Similarly, the alarm can be triggered in the event of a sudden drop in the CO2 concentration below a given minimum value which could be a sign of a new cardiac arrest of the patient, hyperventilation or an obstruction of the circuit gas between the patient and the machine, for example a flexible pipe bent or crushed and no longer allowing the gas to pass. In general, the invention relates to a medical ventilator suitable for use during cardiopulmonary resuscitation (CPR) comprising a source of respiratory gas 1, such as a micro-blower, means for measuring CO2 content 4 , like a capnometer, signal processing and control means 5 receiving and processing the CO2 content measurement signals coming from the CO2 content measurement means 4, and an IGU 7 configured to display at least a maximum value Vmax of CO2 content measured during a given period of time (dt), said maximum value Vmax of CO2 content being selected from a plurality of CO2 content values measured during said given period of time (dt). The respiratory assistance device or medical ventilator according to the present invention is particularly suitable for implementation during cardiopulmonary resuscitation (CPR) on a person (ie a patient) in cardiopulmonary arrest, in the context of which a breathing gas, such as pressurized air, is supplied according to a ventilatory cycle with several pressure levels to said person undergoing cardiac massage with alternating chest compressions and relaxations. To facilitate its transport by first aid workers, for example a doctor, a nurse, a firefighter or the like, the ventilator of the invention is preferably arranged in a transport bag.
    权利要求:
    Claims (14)
    [1" id="c-fr-0001]
    claims
    1. Respiratory assistance apparatus for supplying respiratory gas to a patient during cardiopulmonary resuscitation (CPR) comprising: - a source (1) of respiratory gas for supplying respiratory gas to said patient during cardiopulmonary resuscitation ( RCP), - CO2 content measurement means (4) for performing measurements of the concentration of CO2 produced by said patient, and supplying CO2 content measurement signals to signal processing and control means (5 ), - signal processing and control means (5) configured to process the CO2 content measurement signals coming from the CO2 content measurement means (4), - at least one graphical user interface (7), characterized in that: - the signal processing and control means (5) are configured to: a) process the CO2 content measurement signals corresponding to measurements carried out by the CO2 content measurement means (4) during a period of e given time (dt), and extracting a plurality of CO2 content values therefrom, b) selecting the maximum value (Vmax) of CO2 content from the plurality of CO2 content values measured during said time period (dt) given, and c) transmitting said maximum value (Vmax) of CO2 content to the graphical user interface (7), - and the graphical user interface (7) is configured to display the maximum value (Vmax) of CO2 content .
    [2" id="c-fr-0002]
    2. Apparatus according to the preceding claim, characterized in that the signal processing and control means (5) comprise at least one microprocessor.
    [3" id="c-fr-0003]
    3. Apparatus according to one of the preceding claims, characterized in that the means for measuring the CO2 content (4) comprises a capnometer.
    [4" id="c-fr-0004]
    4. Apparatus according to one of the preceding claims, characterized in that the gas conduit (2) is in fluid communication with a respiratory interface (3), preferably an endotracheal intubation probe, a facial mask or a laryngeal mask .
    [5" id="c-fr-0005]
    5. Apparatus according to one of the preceding claims, characterized in that the means for measuring the CO2 content (4) are arranged: - either upstream and in the immediate vicinity (18) of the respiratory interface (3), - either in the device by being connected to a gas sampling site (18) located upstream and in the immediate vicinity of the respiratory interface (3).
    [6" id="c-fr-0006]
    6. Apparatus according to one of the preceding claims, characterized in that the given time period (dt) is between 2 and 10 seconds, typically of the order of 3 to 6 seconds.
    [7" id="c-fr-0007]
    7. Apparatus according to one of the preceding claims, characterized in that the means for measuring the CO2 content (4) are configured to operate measurements continuously.
    [8" id="c-fr-0008]
    8. Apparatus according to one of the preceding claims, characterized in that it comprises storage means (8) cooperating with the signal processing and control means (5) for storing the plurality of measured CO2 content values during the given time period.
    [9" id="c-fr-0009]
    9. Apparatus according to one of the preceding claims, characterized in that it comprises alarm means configured to trigger when the maximum value of CO2 content exceeds a threshold value, preferably the alarm means comprise a audible or visual alarm.
    [10" id="c-fr-0010]
    10. Apparatus according to one of the preceding claims, characterized in that the graphical user interface (IGU) comprises a digital screen, preferably a touch screen.
    [11" id="c-fr-0011]
    11. Apparatus according to one of the preceding claims, characterized in that the signal processing and control means (5) are configured to control the source (1) of respiratory gas and deliver the respiratory gas according to successive ventilation cycles.
    [12" id="c-fr-0012]
    12. Apparatus according to one of the preceding claims, characterized in that the source (1) of respiratory gas comprises a motorized micro-blower.
    [13" id="c-fr-0013]
    13. Apparatus according to one of the preceding claims, characterized in that the graphical user interface (7) is configured to display the maximum value (Vmax) of CO2 content in the form of a numerical value and / or a Graphic Representation.
    [14" id="c-fr-0014]
    14. Apparatus according to one of the preceding claims, characterized in that the CO2 content measuring means (4) are configured to operate successive CO2 concentration measurements over successive periods of time (dt).
    类似技术:
    公开号 | 公开日 | 专利标题
    US20200383606A1|2020-12-10|Exhaled gas measurement compensation during high flow respiratory therapy
    EP3511043B1|2020-08-19|Ventilation apparatus for cardiopulmonary resuscitation with monitoring and display of the measured maximum co2 value
    EP3510924B1|2020-12-30|Ventilation apparatus for cardiopulmonary resuscitation with display of the co2 tendency
    JP6600460B2|2019-10-30|Airway impedance measurement integrated with respiratory therapy device
    EP3643229A1|2020-04-29|Cardiac monitoring apparatus for cardiopulmonary resuscitation with display of maximum or average co2 content
    EP3302235A1|2018-04-11|Device for diagnosing the efficacy of ventilation of a patient and method for determining the ventilatory efficacy of a patient
    CN108024758B|2021-06-22|Simplified display of end-tidal CO2
    JP2001513387A|2001-09-04|A method and apparatus for determining an image of a user's nasal and / or oral respiratory flow.
    EP3218035B1|2019-05-22|Artificial ventilation apparatus able to deliver ventialtion and monitoring which are specific to the patients receiving cardiac massage
    EP3639735A1|2020-04-22|Monitoring or ventilation device for cardiopulmonary resuscitation with determination of an index of opening of the airways
    EP3218036B1|2018-12-05|Apparatus for artificial ventilation, with monitoring for absence of chest contractions
    EP3299055A1|2018-03-28|Breathing assistance apparatus with automatic detection of manual or automatic cardiac massage mode
    FR3088187A1|2020-05-15|ASSISTANCE APPARATUS FOR CARRYING OUT AN EMERGENCY CARE PROCEDURE, SYNCHRONIZED CARDIOPULMONARY RESUSCITATION ASSISTANCE SYSTEM AND ASSOCIATED METHOD
    WO2020093177A1|2020-05-14|Method and apparatus for continuous management of airway pressure for detection and/or prediction of respiratory failure
    同族专利:
    公开号 | 公开日
    EP3511043A1|2019-07-17|
    EP3511043B1|2020-08-19|
    ES2820285T3|2021-04-20|
    CA3023591A1|2019-07-11|
    JP2019122755A|2019-07-25|
    US20190209795A1|2019-07-11|
    BR102018073943A2|2019-07-30|
    CN110025863A|2019-07-19|
    FR3076462B1|2019-11-29|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    WO2010052608A1|2008-11-07|2010-05-14|Koninklijke Philips Electronics, N.V.|Carbon dioxide monitoring system|
    WO2012114286A1|2011-02-22|2012-08-30|Koninklijke Philips Electronics N.V.|Capnography system for automatic diagnosis of patient condition|
    WO2014045182A1|2012-09-20|2014-03-27|Koninklijke Philips N.V.|Low dead space liquid trap|
    WO2014072981A1|2012-11-12|2014-05-15|Inovytec Medical Solutions Ltd.|System and method for providing non-invasive ventilation|
    US20160287170A1|2014-02-03|2016-10-06|Oridion Medical 1987 Ltd.|Decision support system for cardiopulmonary resuscitation |
    US20160256102A1|2015-03-05|2016-09-08|Oridion Medical 1987 Ltd.|Identification of respiration waveforms during cpr|
    WO2017025869A1|2015-08-10|2017-02-16|Koninklijke Philips N.V.|Simplified display of end-tidal co2|
    DE102012024672A1|2012-12-18|2014-06-18|Dräger Medical GmbH|Respirator and method of operating a ventilator|
    WO2017037565A1|2015-08-31|2017-03-09|Koninklijke Philips N.V.|Monitoring device with multi-parameter hyperventilation alert|DE202020106081U1|2020-08-06|2020-11-05|Isis Ic Gmbh|Health hazard traffic light - CO2 measurement and display to show a potential hazard in rooms and buildings and for documentation in a cloud system|
    DE102020004765A1|2020-08-06|2022-02-10|Isis Ic Gmbh|Health hazard traffic light - CO² measurement and display to show a hazard potential in rooms and buildings and for documentation in a cloud system|
    法律状态:
    2019-01-24| PLFP| Fee payment|Year of fee payment: 2 |
    2019-07-12| PLSC| Search report ready|Effective date: 20190712 |
    2020-01-21| PLFP| Fee payment|Year of fee payment: 3 |
    2021-01-21| PLFP| Fee payment|Year of fee payment: 4 |
    优先权:
    申请号 | 申请日 | 专利标题
    FR1850224A|FR3076462B1|2018-01-11|2018-01-11|VENTILATION APPARATUS FOR CARDIO-PULMONARY REANIMATION WITH MONITORING AND DISPLAYING THE MAXIMUM VALUE OF CO2 MEASURED|
    FR1850224|2018-01-11|FR1850224A| FR3076462B1|2018-01-11|2018-01-11|VENTILATION APPARATUS FOR CARDIO-PULMONARY REANIMATION WITH MONITORING AND DISPLAYING THE MAXIMUM VALUE OF CO2 MEASURED|
    US16/177,618| US20190209795A1|2018-01-11|2018-11-01|Ventilation apparatus for cardiopulmonary resuscitation with monitoring and display of the maximum co2 value measured|
    ES18204428T| ES2820285T3|2018-01-11|2018-11-05|Ventilator for cardiopulmonary resuscitation with monitoring and display of the maximum measured CO2 value|
    EP18204428.9A| EP3511043B1|2018-01-11|2018-11-05|Ventilation apparatus for cardiopulmonary resuscitation with monitoring and display of the measured maximum co2 value|
    CA3023591A| CA3023591A1|2018-01-11|2018-11-07|Ventilation device for cardiopulmonary resuscitation with monitoring and display of the maximum co2 value measured|
    JP2018210411A| JP2019122755A|2018-01-11|2018-11-08|Ventilation device for cardiopulmonary resuscitation including monitoring and display of maximum co2 value measured|
    CN201811376028.XA| CN110025863A|2018-01-11|2018-11-19|The maximum CO of monitoring and display measurement2The air regenerating device for CPR of value|
    BR102018073943-3A| BR102018073943A2|2018-01-11|2018-11-22|CARDIOPULMONARY RESUSCITATION VENTILATION EQUIPMENT WITH MONITORING AND DISPLAY OF MAXIMUM MEASURED CO2 VALUE|
    [返回顶部]