Sensor-patch monitoring of intercostal muscle activity in a patient during assisted ventilation

Abstract

Title of the invention: Monitoring of a patient's intercostal muscle activity during assisted ventilation using a patch sensor. The invention relates to a monitoring system (1) for the respiratory muscle activity of a patient (P), in particular intercostal and / or diaphragmatic muscle activity, comprising a patch sensor (10) including mechanomyography measurement means (13) for performing successive measurements of the patient's muscle activity, and a medical ventilator (20) with control means (25) for processing the measurements performed by the mechanomyography measurement means (13). Display means (30) display an MMG curve (31) representing the patient's muscle activity, in particular intercostal and / or diaphragmatic muscle activity, over time (t) obtained from the processed measurements. Abstract figure: Figure 1

Description

Title of the invention: Sensor-patch monitoring of intercostal muscle activity of a patient during assisted ventilation

[0001] The invention relates to a device for monitoring the respiratory muscle activity of a person comprising a sensor-patch used to track and preferentially record respiratory muscle activity during mechanical ventilation of the person, i.e. of an adult, adolescent or pediatric patient.

[0002] Assisted ventilation aims to replace all or part of the respiratory muscle activity of a patient suffering from acute respiratory failure treated in the hospital or chronic long-term respiratory failure treated at home. It is generally delivered to the patient by a ventilatory support device, also called a respirator or medical ventilator, connected to a gas circuit, called the patient circuit, which is fluid-connected to an endotracheal tube, a breathing mask, or other device, to supply the patient with gas as part of the treatment.

[0003] The respiratory work is shared between the patient and the medical ventilator which delivers the gas according to respiratory cycles in response to the patient's inspiratory effort, i.e. its inspiratory and expiratory phases.

[0004] Whether in invasive ventilation (assisted modes) or non-invasive ventilation, the synchronization of the medical ventilator to the patient's demand must be "optimal", that is to say, perfectly synchronized, and the respiratory assistance provided must be properly titrated, in particular the respiratory assistance delivered to him must be proportional to his demand.

[0005] To optimize mechanical ventilation, it may be necessary to monitor, i.e., track, the patient's respiratory muscle effort during treatment, i.e., during assisted ventilation. This can be done via a measurement of esophageal pressure (EIP) or of the electrical activity of the femoral diaphragm (EAd).

[0006] However, these techniques are complex and require the presence of qualified professionals and the regular replacement of sensors. Furthermore, they require the insertion of a nasogastric esophageal tube in patients, which is highly invasive and poses risks to patients, including damage to their airways and gastric regurgitation.

[0007] One problem, therefore, is to be able to monitor, i.e. track, the patient's respiratory muscle effort during treatment, i.e., during assisted ventilation, which does not present all or some of the problems mentioned above, so as to to be able to ventilate the patient effectively while taking into account their respiratory muscular effort.

[0008] One solution according to the invention relates to a monitoring, i.e. tracking, installation for the respiratory muscle activity of a patient, in particular intercostal and / or diaphragmatic muscle activity, comprising: - at least one sensor-patch comprising mechanomyography (MMG) measurement means configured to perform successive measurements of the patient's muscle activity, and adhesive means for attaching the sensor-patch to the patient's skin, and - a medical ventilator for supplying respiratory gas, including control means for processing measurements taken by mechanomygraphy measuring devices, and - display means to display at least one mechanomyography curve, i.e. MMG representing the patient's muscular activity, in particular intercostal and / or diaphragmatic muscular activity, over time (t) obtained from at least a part of the measurements processed by the control means.

[0009] Furthermore, depending on the embodiment considered, the monitoring installation of the invention may include one or more of the following features: - The ventilator includes a flow source to supply the breathing gas. - The flow source includes a motorized turbine. - Alternatively, the flow source is a gas supply, such as a wall outlet delivering a breathing gas brought in by a gas pipeline which may be part of a hospital gas pipeline network. - Mechanomyography measurement means include a mechanomyography sensor (MMG). - Mechanomyography measurement means are configured to determine sound vibrations (i.e. sound waves) of the patient's respiratory muscles, such as the intercostal and / or diaphragmatic muscles, during their contraction. - the medical ventilator includes display means, in particular a display screen. - the display means are configured to display an MMG curve representing the patient's muscle activity and a gas flow, gas pressure and / or gas volume curve over time (t). - Adhesive media include an adhesive lower surface. - the control means are configured to filter measurements coming from the mechanomyography measurement means. - it includes means for transmitting measurements configured to ensure transmission of measurements operated by the patch sensor to the fan. - the control means are configured to control the flow source according to the measurements operated by the patch sensor. - the measurements are carried out for a duration of ventilation adapted or necessary for the treatment of the patient concerned, for example a duration ranging from several tens of minutes to several hours or several days, or more.

[0010] Depending on the embodiment considered, the patch sensor of the monitoring system of the invention may comprise one or more of the following features: - it includes a secondary electronic board carrying and / or cooperating with the mechanomyography sensor. - the patch sensor comprises a main body or a support matrix. - the mechanomyography measurement means are arranged on the main body. - the main body has a flattened shape. - the adhesive media include a biocompatible adhesive. - it is electrically powered, for example by the fan.

[0011] Depending on the embodiment considered, the fan of the monitoring system of the invention may comprise one or more of the following features: - the control means are configured to control the flow source, typically the motorized turbine, to supply the breathing gas at a given (i.e. desired) flow rate and / or at a given (i.e. desired) pressure. - the control means include one or more microprocessors implementing one or more computer programs, algorithms or the like, in particular at least one microcontroller. - the control means include one (or more) main electronic board(s). - it is electrically powered by mains (110 / 220V) and / or an internal rechargeable battery, in particular via a connection by electrical cables and mains plug. - the display means include a display screen, preferably with color display. - the display screen is preferably touch-sensitive, that is to say it includes a touch-activated panel operated by digital pressure from the user. - the blower is motorized, that is to say equipped with an electric motor. - the flow source, typically the turbine, is fluidly connected to a gas circuit carrying the breathing gas. - the ventilator's gas circuit is fluidly connected to a patient circuit, in particular one or more flexible lines. - the patient circuit carries the gas to a respiratory interface, such as an endotracheal tube, tracheostomy, or non-invasive ventilation mask. - the blower provides a breathing gas such as air, oxygen or an air / oxygen mixture.

[0012] Depending on the embodiment considered, the monitoring installation of the invention may also include one or more of the following features: - means of transmitting measurements configured to ensure transmission of measurements operated by the sensor-patch to the fan, in particular to the fan control means. - the means of transmitting measurements include electrical wires connecting the patch sensor to the fan. - Alternatively, the means of transmitting measurements from the sensor-patch include a wireless transmission module configured to transmit measurements to the fan. Definitions

[0013] Within the scope of the present invention: - the terms "blower", "micro-blower", "turbine", "compressor" or similar are considered equivalent and interchangeable. - the terms "ventilator", "medical ventilator", "assisted ventilation device", "ventilatory assistance device", "respirator" or similar are considered equivalent and interchangeable. - the term “patient” refers to a person or human being, regardless of age or sex, in particular adults, the elderly, adolescents, children, babies and newborns. - A "mechanomyography sensor" is a measuring device capable of measuring muscle activity. Surface mechanomyography is considered the mechanical counterpart of the electrical activity of the motor unit measured by surface electromyography. - The term "respiratory gas" refers to any gaseous compound or mixture of gaseous compounds used to treat a patient, typically air, oxygen (O2), or an air / oxygen mixture. - the term "measurement" refers indifferently to a signal or a value representative of a given quantity.

[0014] The invention will now be better understood with reference to the following detailed description, given by way of illustration but not limitation, with reference to the accompanying figures, among which:

[0015] [Fig-1] schematically illustrates an embodiment of a monitoring installation for the respiratory muscle activity of a patient according to the invention,

[0016] [Fig.2] schematically illustrates an embodiment of a patch sensor usable in the installation of the invention, in particular that illustrated in [Fig.1].

[0017] [Fig.3] is a magnified view of the curves of [Fig.1].

[0018] [Fig. 1] schematically illustrates an embodiment of a monitoring installation 1 of the respiratory muscle activity of a patient P according to the invention, in particular of his external intercostal and / or diaphragmatic muscles.

[0019] The installation 1 includes a medical ventilator 20, i.e. a respiratory support device, equipped with a gas flow source, namely here a motorized turbine 21, i.e. with an electric motor, to supply a respiratory gas, such as air or an air / oxygen mixture, to the patient P. According to another embodiment (not shown), the gas flow source may be a hospital wall outlet supplied with air and / or oxygen under pressure.

[0020] The breathing gas from the gas flow source, e.g., the turbine 21, is delivered to patient P via a patient circuit 23 with one or two branches, i.e., comprising only a breathing branch as illustrated in [Fig. 1] or, according to another embodiment (not shown), an inspiratory branch and an expiratory branch. The patient circuit 23 comprises one or more flexible tubes or the like.

[0021] The patient circuit 23 supplies a respiratory interface 22 providing gas to patient P, such as a respiratory mask, a tracheal intubation tube, a tracheostomy device or similar.

[0022] The fan 20 also includes control means 25, i.e. data processing means, such as one (or more) microprocessor electronic card(s), used in particular to process measurements, i.e. signals, values ​​or others, operated by a mechano-myography sensor, as explained below.

[0023] The control means 25 also allow the gas supply to be controlled or controlled by the gas flow source, i.e. here by the motorized turbine 21 according to ventilation cycles, in particular ventilation cycles memorized within storage means (not shown) arranged in the fan 20, such as a flash memory or similar.

[0024] The control means 25 comprise at least one microprocessor implementing one or more algorithms, preferably carried by one or more electronic boards, such as a microcontroller. The electronic board may also incorporate the storage means.

[0025] Furthermore, display means 30, such as a color display screen, advantageously a touchscreen, are used to display information, graphical representations like curves, bar graphs, etc., icons, alarm messages, or any other useful information. The displays are preferably managed by a graphics card which is controlled by the control means 25.

[0026] The ventilator 20 also includes other conventional components, such as an internal gas circuit 24 for conveying the breathing gas from the turbine to the patient circuit 23; power supply means, such as cables / mains plug (110 / 220V), rechargeable battery...; adjustment or selection means 26, such as buttons, keys or the like...

[0027] The turbine 21, the control means 25, the internal gas circuit 24 and other components are arranged in the outer shell or casing 27 of the fan 20.

[0028] Furthermore, the ventilator 20 also includes pressure measurement means, typically a pressure sensor (or sensors), and flow determination means, typically a flow sensor (or sensors), which can be arranged on the internal gas circuit 24 of the ventilator 20 and / or on the patient circuit 23 in order to measure or determine a gas pressure (or pressures), for example the airway pressure of patient P and / or a gas flow (or flows), in particular the gas flow in the internal gas circuit 24 of the ventilator 20.

[0029] The pressure and / or flow measurements taken by these sensors are returned to the control means 25 of the fan 20 where they are processed, in particular to control the supply of gas by the gas source, typically the motorized turbine 21 or to determine the volume or volumes of gas exchanged, for example the inspired volume and the exhaled volume, from successive measurements in particular of gas flow.

[0030] According to the invention, (at least) a sensor-patch 10 is used to perform measurements of the patient's muscle activity and to detect the oscillations of the patient's external intercostal muscles on which the sensor-patch 10 is fixed.

[0031] More specifically, this sensor-patch 10 includes a support element comprising a mechanomyography sensor 13 (MMG) configured to operate measurements of the muscle activity of patient P, and adhesive means for sticking the sensor-patch to the skin of patient P, in particular an adhesive surface 14, as illustrated in [Fig.2] and detailed below.

[0032] The sensor-patch 10 is non-invasive, that is to say, it is positioned on the surface of the patient's body P, i.e. on his skin 50, in particular stuck in one (or more) (inter)costal and / or diaphragmatic region, for example at the level of the second intercostal space, in order to carry out measurements of the muscular activity of the patient's external intercostal muscles, during his respiratory cycles, in particular during his successive inspiratory and / or expiratory phases.

[0033] Furthermore, the sensor-patch 10 communicates with the control means 25 of the fan 20 via one (or more) wired links 11, as illustrated on [Fig.1], or according to another embodiment, via wireless communication means (not shown), in order to provide the measurements to said control means 25 which process them, in particular which filter them, in particular to allow them to be displayed on the screen 30, in particular in the form of curves.

[0034] In order to enable the bonding, i.e. adhesion, of the non-invasive sensor-patch 10 to the skin of the patient, whether adult, adolescent or pediatric, it includes an adhesive lower surface, for example coated or formed with a biocompatible adhesive layer, which comes into direct contact with the skin 50 of the patient P.

[0035] As detailed below, the patch sensor 10 incorporates mechanomyography measurement means (MMG) 13, such as an MMG sensor, configured to perform measurements of muscle activity in one or more thoracic regions of the patient, typically one or more intercostal regions 51, i.e., capable of measuring a mechanical signal corresponding to oscillations of the muscle surface in one (or more) intercostal region 51 of the patient. These oscillations are caused by the mechanical movement of the body's motor units, namely the muscles of the intercostal regions 51 of patient P, particularly when inhaling gas, such as air or an air / O2 mixture.

[0036] In other words, the mechanomyography measurement means 13, i.e. the MMG sensor, of the patch sensor 10, not only allow for the acquisition, over time, of measurements reflecting the oscillations of the muscle surface in the costal region(s) 51 of the patient, but also for their transmission to the mechanical ventilation device, i.e. the ventilator 20, where they are processed, displayed in the form of graphical representations 23, such as curves for example, and preferably used to (reverse)control the turbine 21

[0037] The patch sensor 10 thus makes it possible to monitor the patient's respiratory muscle activity during mechanical ventilation provided by the medical ventilator 20, by means of a graphical representation 31 displayed on the ventilator's display screen 30, whether this display is live, i.e., during the patient's treatment, or retrospectively, and preferably in conjunction with other signals provided by the fan 20, such as flow and / or pressure signals, or the volumes supplied.

[0038] [Fig.2] schematically illustrates an embodiment of a patch sensor 10 usable in a monitoring installation 1 according to the invention.

[0039] As can be seen, the patch sensor 10 comprises a main body 12 or support matrix comprising: - the lower adhesive surface 14, i.e. self-adhesive, intended to be glued to the patient's skin 50, typically in an intercostal region or space 51 of patient P, and - the means of mechanomyography measurement 13, i.e. an MMG sensor, used to measure the vibrations of the muscles of the intercostal and / or diaphragmatic regions 51, during their contractions, during the inspiratory and / or expiratory phases of patient P.

[0040] The main body 12 is advantageously flat, that is to say it has a height of less than 3 cm and a width of less than 10 cm, or other dimensions.

[0041] The patch sensor 10 can integrate a secondary electronic board allowing the data from the MMG sensor to be integrated and / or transmitted to the fan where it is processed.

[0042] Generally, within the framework of the present invention, the sensor-patch 10 captures and transmits the MMG signal, i.e. muscle vibration measurements, of the external intercostal muscles 51 of patient P which contract in particular with each voluntary inspiration of the latter.

[0043] In the embodiment of [Fig. 1] and [Fig. 2], the MMG sensor 13 is connected to the fan 20 via one or more wired electrical connections 11, in particular an electrical cable. However, a wireless connection is also possible, for example via Bluetooth®, Wi-Fi, or any other suitable communication protocol.

[0044] Preferably, the sensor-patch 10 is made, at least in part, of biocompatible material(s), i.e. of material(s) tolerated by the human body, in particular its adhesive surface 14 coming into contact with the skin 50 of the patient.

[0045] The main body 12 of the sensor-patch 10 can be made of polymer. Advantageously, it has a certain degree of flexibility so as to conform well to the contours of the intercostal regions 51 of the patients.

[0046] The display screen 30 of the ventilator 20, as illustrated in [Fig. 1], displays the curve 31 reflecting the mechanomyography (MMG) signal, captured, for example, at the second, third, or fourth intercostal space of a mechanically ventilated patient P, obtained using a respiratory muscle activity monitoring system 1 of patient P according to the invention, such as that of [Fig. 1], and also the flow signal reflected by the flow curve 32. However, according to the embodiment Depending on the chosen option, we could also display a gas pressure and / or gas volume curve.

[0047] Such a display in the form of curves 31, 32 can be done on the graphic display 30 of the fan 20, for example during the use of the monitoring installation 1 according to the invention or, according to another embodiment, on a remote display screen of another device, for example that of a laptop, desktop computer, digital tablet, multifunction phone (smartphone) or other, as explained below.

[0048] As more clearly seen in [Fig. 3], curve 31 corresponds to the signal of MMG obtained from the signals from the patch sensor 10 and curve 32, corresponding here to the gas flow signal, are shown over time (t). It can be seen that the MMG measurements accurately reflect the gas flow and can therefore be used to monitor patient ventilation and, preferably, to provide feedback control of the gas supply by the flow source, typically the turbine 21.

[0049] In [Fig. 3], it is shown that a curve 31 is obtained that is essentially identical whether the raw signal SB (solid line) from the patch sensor 10 or the filtered signal SF (dashed line----) is used, since the two curves SB and SF overlap. Preferably, however, the filtered signal is used.

[0050] More generally, thanks to the MMG signal, the fan 20 can be controlled in several ways as explained below.

[0051] First, the operation of the ventilator 20 can be controlled in so-called "open loop". In this case, the patch sensor 10 allows for live monitoring, via MMG measurements of the intercostal inspiratory muscles, during patient ventilation, with display of a corresponding curve 31 on the screen 30 of the ventilator 20, and also of one (or more) flow curve 32, or as the case may be, of pressure and / or volume.

[0052] This allows for real-time evaluation, during ventilation treatment of patient P, of the synchronization and adequacy between patient P's gas demand, patient P's respiratory effort and the mechanical ventilation operated.

[0053] Alternatively, monitoring or tracking can also be carried out "post-hoc," that is, after the fact, of the synchronization between the patient's respiratory demand and the mechanical ventilation provided, for example, in the form of a respiratory polygraphy or similar device, accessible on software implemented by an auxiliary device with a display screen, i.e., a computer, tablet, smartphone, etc. In this latter case, the data and measurements are recorded during the patient's treatment, by the ventilator's storage means 20, and then transmitted or provided to the auxiliary device, for example, as a raw data file, via remote wired transmission or via a storage medium. data, such as an SD card, USB drive, or other storage device. The MMG signal can be retrieved or downloaded by the ancillary device and post-processed there, for example, within a computer program (software) that allows the signal to be plotted over time. The resulting curves 31, 32 can then be consulted afterward to verify whether the treatment applied to patient P was effective or not, that is, whether it was in line with the patient's gas demand.

[0054] Finally, the operation of the fan 20 can be controlled in a so-called "closed loop" by controlling the operation of the fan 20 based on the MMG signal received by the MMG sensor 13. Such control may include: - triggering of the ventilator cycles 20, i.e. the gas insufflations, according to the inspiratory calls of patient P according to the MMG signal from the MMG sensor 13. - a cycling, namely the transition from the inspiratory phase to the expiratory phase on the ventilator 20 according to the MMG signal from the MMG sensor 13. - a quantity of respiratory assistance delivered by the ventilator 20 according to the patient's detected inspiratory demand and the MMG signal from the MMG sensor 13.

[0055] Generally, the MMG signal is processed instantaneously and in real time within the fan 20, i.e. by the control means 25, i.e. data processing, and then displayed (as a function of time t) on the display screen 30 of the fan 20 or of an auxiliary device, i.e. remote.

[0056] Preferably, actions can be performed on the display screen 30, in particular when it is a touch screen, for example a digital press of the user on the screen panel allows to activate certain functions or to make choices, selections, settings or other actions.

[0057] Advantageously, the data or measurements will be retrieved by the fan 20 at an acquisition frequency between 1 and 2000 Hz, for a ventilation duration ranging from 1 min to 80 h.

[0058] Finally, when the MMG signal is used to control the ventilatory parameters of ventilator 20 in real time, means are provided on the ventilator to inform the user when ventilator 20 is triggered or not triggered by the MMG signal. Furthermore, means are also provided to validate the correct placement of the MMG sensor on the patient, particularly on the ventilator's display.

Claims

Demands

1. A monitoring installation (1) for the respiratory muscle activity of a patient (P), in particular intercostal and / or diaphragmatic muscle activity, comprising: - at least one patch sensor (10) including mechanomyography measurement means (13) configured to perform successive measurements of the patient's muscle activity, and adhesive means (14) for sticking the patch sensor (10) to the patient's skin (50), and - a medical ventilator (20) for supplying a breathing gas, including control means (25) for processing the measurements performed by the mechanomyography measurement means (13), and - display means (30) for displaying at least one MMG curve (31) representing the patient's muscle activity, in particular intercostal and / or diaphragmatic muscle activity, over time (t) obtained from at least a portion of the measurements processed by the control means (25).

2. Installation according to claim 1, characterized in that the fan (20) includes a flow source (21) for supplying a breathing gas, preferably the flow source includes a motorized turbine (21) or a wall outlet supplying gas.

3. Installation according to claim 1, characterized in that the mechanomyography measurement means (13) comprise a mechanomyography sensor (MMG).

4. Installation according to claim 1, characterized in that the mechanomyography measuring means (13) are configured to determine sound vibrations of the respiratory muscles, such as the intercostal and / or diaphragmatic muscles, of the patient, during their contraction.

5. Installation according to claim 1, characterized in that the medical ventilator (20) includes display means (30), in particular a display screen.

6. Installation according to claim 1, characterized in that the display means (30) are configured to display a curve (31) of MMG representing the patient's muscle activity, in in particular intercostal and / or diaphragmatic muscle activity, and a gas flow curve (32), gas pressure and / or gas volume, over time (t).

7. Installation according to claim 1, characterized in that the adhesive means (14) comprise an adhesive lower surface.

8. Installation according to claim 1, characterized in that the control means (25) are configured to filter measurements from the mechanomyography measurement means (13).

9. Installation according to claim 1, characterized in that it comprises measurement transmission means (11) configured to ensure transmission of measurements operated by the patch sensor (10) to the fan (20).

10. Installation according to claims 1 and 2, characterized in that the control means (25) are configured to control the flow source (21) according to the measurements operated by the patch sensor (10).

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