FR3019992A1 - AUTONOMOUS OXYGEN CONCENTRATION MEASUREMENT MODULE FOR ASSISTED VENTILATION APPARATUS - Google Patents

Abstract

An autonomous gas concentration measuring module (1) for assisted ventilation apparatus (20) comprising an internal gas passage (2) connecting a gas inlet port (3) to an outlet port gas (4); gas concentration measuring means (5) arranged on or in the internal gas passage (2) so as to determine at least one signal representative of the concentration of a given gaseous compound within said internal gas passage ( 2); signal processing means (6), connected to the concentration measuring means (5), for processing said at least one measurement signal and deriving at least one concentration value from said given gaseous compound; power supply means (7) supplying electric power, the signal processing means (6) and the measuring cell (5); and fastening means (8) for securing the module (1) to the gas outlet (21) of an assisted ventilation apparatus (20). An assisted ventilation apparatus (20) comprising an air outlet (21 and such an independent module (1) attached at said air outlet (21).

Description

The invention relates to an autonomous module for measuring gas concentration designed to be connected to the gas outlet of a medical fan and for determining the content of a given gaseous compound contained in a gaseous mixture, typically the oxygen content. oxygen-enriched air or air, as well as a medical ventilator equipped with such a module and an oxygen-enriched air or air supply installation comprising an oxygen source supplying a ventilator equipped with such a measurement module.

In the medical field, it is usual, in the context of a medical assisted ventilation, to provide urgently air or air enriched with oxygen to patients suffering from respiratory problems, such as asthma attack, COPD , SOH, neuromuscular, cystic fibrosis, ... For this purpose, it is conventionally used a respiratory assistance device for performing a medical ventilation of the patient's airways. This type of device is also called assisted ventilation device, two-level pressure fan or simply medical fan. In this type of apparatus, atmospheric air is sucked by a micro-blower, also called turbine, which is arranged in the apparatus, then the air flow set in motion by the impeller of the turbine is then sent to the airways of the patient, via a flexible gas pipe and a patient interface, such as a respiratory mask, for example of the nasal, nasal or facial type. Such an apparatus is for example marketed by the company Air Liquide Medical Systems under the trade name Monnal T60 which is designed to be used during emergency medical interventions in all intensive care environments, namely both at the hospital. 'outside the hospital. Respiratory masks are described in particular by EP-A-2679266, EP-A2510823 or EP-A-2329858. In this type of apparatus, it is necessary to monitor or monitor the patient's F02 (ie Fraction of inspired oxygen), that is, the inspired fraction of oxygen. .

To do this, it is necessary to perform a determination or measurement of the oxygen concentration in the flow of oxygen enriched air or not sent to the patient so as to ensure that the proportion of oxygen that it receives corresponds to the desired Fi02.

For this purpose, an oxygen measurement cell arranged downstream of the fan turbine and connected to processing means, such as an electronic card, located in the fan shell via dedicated connection means, such as the one described above, is conventionally used. a cable or the like, which are either integrated with the fan or external. This brings with it problems and disadvantages.

First, it requires to provide specific processing means within the fan, including algorithms, as well as mechanical and electrical connectors adapted. Then, it complicates the architecture of the fan, especially when the connection is fully integrated into the fan shell.

Conversely, when the connector implements one or more external cables, then it is the general ergonomics of the fan that is negatively impacted and there is a risk of inadvertent disconnection of the cable, making the monitoring of the content of the cable. impossible oxygen. The present invention aims to solve all or part of these problems and disadvantages. The solution of the invention then relates to an autonomous measurement module for performing a determination of the oxygen content of an air stream possibly enriched with oxygen. More specifically, the invention relates to an autonomous gas concentration measurement module for assisted ventilation apparatus comprising: an internal gas passage connecting a gas inlet orifice to a gas outlet orifice; for measuring gas concentration arranged on or in the internal gas passage so as to determine at least one signal representative of the concentration of a given gaseous compound, within said internal gas passage, - signal processing means connected to the concentration measuring means, for processing said at least one measurement signal and for deriving at least one concentration value from said given gaseous compound, - electrical supply means supplying electric current, the means signal processing and measuring cell, and - fixing means for securing the module to the gas outlet of a power assisted ventilation device. Depending on the case, the autonomous module according to the invention may comprise one or more of the following technical characteristics: the concentration measuring means comprise a measuring cell and / or an electronic sensor. the concentration measuring means are designed for and capable of determining at least one signal representative of oxygen concentration. the signal processing means comprise at least one electronic card. - At least the internal gas passage, the gas concentration measuring means and the signal processing means are included in a housing. - The case forms a sealed outer envelope. - The fastening means comprise at least one mechanical connection 20 - the fastening means are designed to allow the joining or, conversely, the detachment of the fan module, according to the needs of the user. the power supply means comprise at least one electrical cable or the like or any associated equipment, for example one or more electrical wires, connectors, etc., it furthermore comprises signal transmission means for transmitting said signal. at least one concentration value of said given gaseous compound treated by the signal processing means to control means or data display means of a power assisted ventilation apparatus (20), preferably the means for signal transmissions (11) comprise one or more connectors, cables ... - the internal passage of gas is a conduit, for example of tubular form without loss of load. the internal gas passage is adapted to and designed to convey air or air enriched in oxygen, that is to say typically containing at least 20% by volume of oxygen, preferably between 21 and 40% by volume of oxygen, generally less than 30%. - The case forms a shell or outer shell sealed. the housing is made of a polymer material, typically made of plastic and / or elastomer. - The internal gas passage opens, downstream, in a gas pipe, in particular a flexible pipe connecting the fan to the user, via a breathing mask or the like. The invention also relates to an assisted ventilation apparatus comprising an air outlet, characterized in that an autonomous module according to the invention is fixed at said air outlet.

Preferably, it comprises data display means cooperating with the module signal processing means for displaying said at least one concentration value of said given gaseous compound processed by the signal processing means. Preferably, the oxygen source supplying the assisted ventilation apparatus to enrich oxygen, the air sucked by the turbine of said apparatus is an oxygen container, an oxygen line or an oxygen concentrator. The present invention will now be better understood by means of the following detailed description, given by way of illustration, with reference to the appended figures in which: FIG. 1 represents a possible embodiment of an autonomous gas concentration measurement module for assisted ventilation device according to the present invention, - Figure 2 shows the module of Figure 1 connected to the gas outlet of a power assisted ventilation device, - Figure 3 schematizes the operating principle of the fan of Figure 2 equipped of the module of Figure 1, and - Figure 4 shows schematically the operating principle of the autonomous module of the invention and its cooperation with the Figure 2. Figure 1 shows an embodiment of an autonomous module 1 of gas concentration measurement for assisted ventilation device 20 according to the present invention and more particularly, for measuring the concentration of oxygen ntenu in a gaseous mixture, typically a flow of air or air enriched in oxygen, delivered by a fan 20. More specifically, the autonomous module 1 of the invention comprises a housing 10 forms a shell or outer shell tight. Advantageously, it is made of polymer material, typically plastic and / or elastomer. The housing 10 is fixed to the outlet 21 of a fan 20, as illustrated in FIGS. 2 and 3. It comprises, on the rear side 10b, an inlet orifice 3 through which the flow of gas delivered by the turbine 23 of the fan 20 penetrates into the module 1, and, on the front side 10a, an outlet orifice 4 through which the oxygen-enriched gas stream exits the module 1. The inlet and outlet ports 4 and 4 are fluidically connected to one another. to the other by a passage or conduit 2 internal gas passing through the module 1. The output 21 of the fan 20 is therefore in fluid communication with said internal passage 2. In order to allow the attachment of the module 1 to the gas outlet 21 of the fan 20, the rear side 10b of the housing 10 forming the body of the module 1 is equipped with fastening means 8, such as a set of mechanical clips or a movable latch that can be actuated upon disconnection of the module 1. In all cases, the module 1 of the invention is It is detachable and is therefore designed to be easily connected to or, conversely, disconnected from a medical ventilator by a user, such as nursing staff. Advantageously it is designed to be attached to the output of existing medical fans, such as an interface provided for a humidification accessory, without it being necessary to adapt them to receive it. Furthermore, according to the present invention, gas concentration measurement means 5 are provided arranged on the internal passage of gas 2 making it possible to determine one (or more) signal representative of the concentration of a given gaseous compound, typically of oxygen, in the gas stream passing through the internal gas passage 2 of the module 1. The gas concentration measurement means 5 comprise a measuring cell 9 such as a chemical cell or an electronic sensor which once connected ( e) by a mechanical connection means such as a screw system, is in contact with the gas stream traveling in the internal gas passage 2. The gas concentration measuring means 5 are supplied with electric current by power supply means 7 such as electric wires or cables or the like.

As can be seen in FIGS. 1 to 3, the housing 10 comprises a lateral protuberance 10c, located here under the housing 10, comprising at least a portion of said gas concentration measuring means 5 and to which electrically connected son of power supply 7 equipped with quick connectors. Furthermore, the module 1 also comprises signal processing means 6, for example an electronic card that can be equipped with power conversion means, signal conversion, a processor-controlled intelligence, which are electrically connected. the concentration measuring means 5 so as to be able to recover and then process the measurement signal (s) emanating from the concentration measuring means 5 in order to deduce therefrom (or) concentration value of the given gaseous compound, such as oxygen, in the gas stream analyzed, typically air enriched or not with oxygen. The signal processing means 6 are also supplied with electric current by power supply means, such as cables or electrical wires, connectors or any other usual connector component.

Figure 4 schematizes the operation of module 1 and its interactions with the medical ventilator 20 to which it is attached. As an example, an air stream having been enriched with oxygen upstream or in the fan 20 and whose oxygen content is to be known at the fan outlet.

As it is understood, the internal gas passage 2 of the module 1, which connects the gas inlet port 3 to the gas outlet port 4, is in fluid communication with the gas-fed outlet 21. that is to say in oxygen enriched air, by the fan 20, via a gas duct 24 located downstream of the turbine 23 (FIG 3). During its passage in the internal gas passage 2 of the module 1, the oxygen-enriched air stream comes into contact with the measuring cell 9 of the concentration measurement means 5. The standard measuring cell 9 then operates a (or several) measurement of the oxygen content contained in the air flow in the passage 2 and the (or) signal resulting from this 02 concentration measurement is then transmitted to the signal processing means 6 contained in the rear part 10b of the module 1.

The signal processing means 6 then operate a processing of (said) measurement signal in order to deduce one (or more) oxygen concentration value from the air flow. Then, the signal processing means 6 transmit, via a suitable connector 11, the oxygen concentration value to the control means 25 of the fan 20. This oxygen concentration value can be stored therein. It can also be displayed on a display 26, preferably digital. As mentioned above, in the embodiment shown in FIGS. 2 and 3, the air which is sucked by the turbine 23 of the fan 20, enters the fan 20, passing beforehand through a second detachable module 27.

In this second detachable module 27, the air is preferably filtered by one (or more) filter, before being optionally enriched with oxygen by adding additional oxygen gas, via an oxygen supply line 28 coming to connect fluidly. said second detachable module 27. In order to rid the incoming air atmospheric impurities therein, such as dust, pollen, bacteria ...., preferably uses at least one particulate filter, preferably a filter type HEPA (ie High-efficiency Particulate Absorption = High Efficiency Particle Absorption). In addition, the line 28 is fed by an oxygen line, an oxygen concentrator, an oxygen container, such as an oxygen cylinder, or any other source of oxygen or an oxygen-rich gas. .

The enriched oxygen air (or not) emerging from the second detachable module 27 is then conveyed by an upstream duct 22 to the turbine 23, being sucked by it, before being conveyed to the measurement module 1 via the downstream conduit 24, as explained above.

After passing through the measurement module 1, the air is conventionally brought to the patient, via for example a flexible conduit and a breathing mask. For the majority of patients (i.e., 80 to 90%), the delivered oxygen-enriched airflow typically contains a proportion of about 10 to 20% oxygen from the oxygen source.

In general, it is advantageous to provide module detection means making it possible to detect and automatically recognize the presence of the module 1 at the fan output 20. The module detection means comprise, for example, a detection of the electrical connection of the connectors. by a signal sending or by a light signal generated by an indicator indicating the proper connection of the module 1. Of course, the autonomous module 1 of the invention can take different forms and is not limited to the embodiment of FIGS. . The module 1 according to the invention has the following advantages: - be of simple design and inexpensive. - Can be used on many existing fans, possibly through the use of a simple adapter to allow its attachment to the air outlet of the fan in question. - be easy maintenance and inexpensive. - do not require immobilization of the entire fan in case of module failure. It is sufficient for the user to use another module during the repair of the damaged one. - do not complicate the architecture of the fan because the measurement and signal processing functions are exported outside the fan. It also simplifies its maintenance.30

Claims (10)

REVENDICATIONS1. Autonomous gas concentration measuring module (1) for assisted ventilation apparatus (20) comprising: - an internal gas passage (2) connecting a gas inlet (3) to a gas outlet (4) ), gas concentration measuring means (5) arranged on or in the internal gas passage (2) so as to determine at least one signal representative of the concentration of a given gaseous compound, within said internal passageway of gas (2), - signal processing means (6), connected to the concentration measuring means (5), for processing said at least one measurement signal and deriving at least one concentration value therefrom. said given gaseous compound, - electric supply means (7) supplying electric current, the signal processing means (6) and the measuring cell (5), and - fixing means (8) for securing the module (1) at the gas outlet (21) of an assisted ventilation apparatus (20) . 2. Module according to the preceding claim, characterized in that the concentration measuring means (5) comprise a measuring cell (9) or an electronic sensor. 3. Module according to one of the preceding claims, characterized in that the concentration measuring means (5) are designed for and able to determine at least one signal representative of oxygen concentration. Module according to one of the preceding claims, characterized in that the signal processing means (6) comprise at least one electronic card. 5. Module according to one of the preceding claims, characterized in that at least the internal gas passage (2), the gas concentration measuring means (5) and the signal processing means (6) are included in a box (10). 6. Module according to one of the preceding claims, characterized in that the housing (10) forms a sealed outer envelope. 7. Module according to one of the preceding claims, characterized in that the power supply means (7) comprise at least one electric cable. 10 8. Module according to one of the preceding claims, characterized in that it further comprises signal transmission means (11) for transmitting said at least one concentration value of said given gaseous compound treated by the processing means signal (6) to control means or data display means 15 of an assisted ventilation apparatus (20). 9. Module according to one of the preceding claims, characterized in that the signal transmission means (11) comprise one or more connectors and / or cables 20 Assisted ventilation apparatus (20) comprising an air outlet (21), characterized in that an autonomous module (1) according to one of the preceding claims is fixed at said air outlet (21). .