Nitric oxide delivery system flow sensor connection reversal alert

Abstract

Title of the Invention: Reverse Connection Alert for the Flow Sensor of a Nitric Monoxide Delivery System. The invention relates to a gas delivery system (100) for supplying a gas containing NO to a patient, comprising an NO delivery device (1) including at least one internal passage (6) for conveying the gas flow, microprocessor-controlled control means (8) (9), and a graphic display (4); a patient circuit (20) to which the NO delivery device (1) is fluidly connected; and a flow measurement device (25) fluidly connected to the patient circuit (2). The control means (8) are configured to process the flow measurements to display a visual alarm on the graphic display (4) in the event of a reverse connection of the flow measurement device (25). Abstract Figure: Figure 4

Description

Title of the invention: Alert for reversal of connection direction of the flow sensor of a nitrogen monoxide administration installation

[0001] The invention relates to an apparatus or device for supplying and monitoring a gas containing nitrogen monoxide (NO), in particular a NO / N2 gas mixture, commonly called a NO supply apparatus, and an installation for administering NO comprising such a NO supply apparatus connected to a patient circuit comprising a flow sensor, which can be used to treat one or more persons suffering from acute pulmonary arterial hypertension, comprising alert means signaling any incorrect connection of the flow sensor of the patient circuit.

[0002] Inhaled nitric oxide (NOi) is a standard treatment for treating people, i.e. patients, suffering from acute pulmonary arterial hypertension. Indeed, when inhaled, NO dilates the pulmonary vessels and increases oxygenation by improving gas exchange. These properties are used to treat various medical conditions, such as Persistent Pulmonary Hypertension of the Newborn or PPHN (for Newborn Pulmonary Hypertension), Acute Respiratory Distress Syndrome or ARDS observed mainly in adults or pulmonary hypertension (PH) in cardiac surgery in adults or children, as described in particular by EP-A-560928, EP-A-1516639 and US-A-10,201,564.

[0003] Usually, a small quantity of gaseous NO (i.e. a few ppm vol.), diluted in nitrogen (N2), is injected and diluted in a gaseous flow containing oxygen, typically at least approximately 20% vol. of oxygen (O2), such as an N2 / O2 mixture or air, or even pure oxygen, which is conveyed by the patient circuit of a gas supply installation, and the final gaseous mixture obtained containing NO and oxygen is then inhaled by the patient. The final NO concentration, which corresponds to a dosage, is determined by the doctor or the like. In general, it is between 1 and 80 ppm by volume (ppmv), typically in the order of 10 to 20 ppmv, depending on the population treated, i.e. newborns, children, adolescents or adults, and the disease to be treated, in the final NO / N2 / O2 gas administered by inhalation to the patient in question, i.e. after injection of the NO / N2 mixture into the flow of gas containing oxygen (i.e. approximately >20% vol.) carried by the patient circuit.

[0004] The implementation of a NOi treatment usually comprises several materials constituting a NO administration installation, in particular a NO supply and monitoring device, a medical ventilator supplying a gas containing oxygen (typically at least 21% vol. approximately) from one (or more) gas cylinders, an NO injection line and a patient kit comprising a patient circuit equipped with a flow sensor and a respiratory interface, such as a tracheal intubation tube or a respiratory mask, or even other elements, such as a gas humidifier or other.

[0005] All these materials must be ready for an urgent start of NOi treatment, as soon as the doctor prescribes it. However, the care teams, i.e. doctors, nurses or other nursing staff, working in the intensive care and surgery departments of the hospitals where NOi is administered, carry out care and medical procedures on a daily basis, which can lead to certain errors during the connections and other connections of the different materials of the NO administration installation.

[0006] In particular, it frequently happens that care teams make a mistake in connecting the flow sensor to the inspiratory branch of the patient circuit and do not notice it. However, such a reversal of direction is very problematic because it causes erroneous measurements of the gas flow coming from the medical ventilator, circulating in the inspiratory branch of the patient circuit, which can cause incorrect dosages, i.e. overdose or underdose, of the proportion of NO injected by the NO supply device into the inspiratory branch of the patient circuit.

[0007] It is easy to understand that such poor dosages can seriously harm the health of the patient inhaling the gas because they do not correspond to the dosage set by the doctor, i.e. the concentration of NO to be provided.

[0008] In view of this, a problem is therefore to be able to avoid or minimize the risk of incorrect dosages resulting from incorrect connection, typically from a reversal of direction, of the flow sensor within the inspiratory branch of the patient circuit, that is to say to avoid or minimize the risk that the nursing staff does not realize that the flow sensor has been incorrectly connected and starts a treatment with an incorrectly connected sensor.

[0009] A solution of the invention then relates to a gas administration installation for supplying a gas containing NO, i.e. a gas mixture containing NO, to a patient comprising: - an NO supply device comprising at least one internal passage for conveying a flow of gas containing NO, microprocessor control means, and a graphic display, - a patient circuit to which said NO supply device is fluidly connected to supply the gas containing NO to said patient circuit, and - a flow measurement device fluidly connected to the patient circuit to measuring at least one gas flow rate and connected to the control means of the NO supply device to provide said control means with at least one flow rate measurement,

[0010] According to the present invention, the control means of the NO supply apparatus are configured to: - processing said at least one flow measurement from the flow measuring device to detect a reversal of the direction of connection of the flow measuring device to the patient circuit, and - display a visual alarm on the graphic display if a reversal of the connection direction of the flow measuring device is detected.

[0011] According to the embodiment considered, the NO supply apparatus, i.e. of de delivery of a gaseous stream containing NO, may include one or more of the following characteristics: - the flow measuring device is electrically or pneumatically connected to the control means of the NO supply device. - the control means cooperate with the graphic display so as to control the displays on said graphic display of the NO supply device. - the visual alarm displayed includes an information message, e.g. an alert message, mentioning a reversal of the connection direction of the flow measuring device. - the alert message may include alphanumeric characters, an alert icon, a graphical representation or other. - it includes storage means, such as computer memory, in particular flash memory or other. - said information message mentioning a reversal of the direction of connection of the flow measuring device is stored in the storage means. - the flow measuring device includes a flow sensor or a pressure sensor. - the flow sensor is of the mass, hot wire or pressure differential type, preferably a mass flow sensor. - the flow rate measuring device further comprises a tubular body crossed by an internal channel and comprising mechanical connection means making it possible to secure said tubular body to the patient circuit. - the mechanical connection means include connectors or the like. - the mechanical connection means are of the connection type by screwing, by interlocking, bayonet or other. the control means are configured to control a display within a display window of said information message. the control means are configured to detect a reversal of the direction of connection of the flow measurement device to the patient circuit by determining a negative gas flow, i.e. in a circulation of the gas flow in the opposite direction (i.e. negative direction) to the expected direction (i.e. the expected direction or positive direction is that going from the medical ventilator to the patient) from said at least one flow measurement coming from the flow measurement device. the control means are configured to process said at least one flow measurement coming from the flow measurement device to deduce therefrom an inversion of the direction of connection of the flow measurement device to the patient circuit. the control means are configured to process said at least one flow measurement by means of at least one algorithm. said at least one internal passage comprises valve means. the control means are configured to control the valve means to authorize or prevent / stop a circulation of gas in said at least one internal passage. the control means are further configured to prevent any launch (i.e. start-up) of treatment in the event of detection of a reversal of the direction of connection of the flow measurement device. the control means are further configured to control the valve means to prevent or block the supply of a flow of NO through said at least one internal passage in the event of detection of a reversal of the direction of connection of the flow measuring device. in the event of detection of a reversal of the direction of connection of the flow measuring device, the device, in particular the control means, can also propose or trigger an emergency dosing procedure, i.e. an emergency dosing. the control means of the NO supply apparatus are configured to control valve means arranged on said at least one internal passage of the NO supply apparatus to prevent or block the supply of a flow of gas containing NO through the internal passage in the event of detection of a reversal of the direction of connection of the flow measuring device, i.e. to prohibit any start of treatment of the patient using the installation of the invention. the graphic display is a touch-sensitive graphic display controlled by the control means, that is to say that the control means control the displays operated on the graphic display. the device is configured to operate monitoring and supply of gaseous NO, i.e. gas containing NO, such as a NO / N2 mixture, the (at least one) internal passage allows the flow of gas containing NO to be conveyed between (at least) one gas inlet and (at least) one gas outlet supplying the gas containing NO, i.e. an NO / N2 mixture. the device comprises a gas analysis line comprising at least one sensor electrically connected to the control means, i.e. one or more sensors. said at least one sensor comprises one or more electrochemical cells. the gas analysis line comprises a NO sensor configured to measure a concentration (i.e. content or dose) of NO, a NO2 sensor configured to measure a concentration (i.e. content or dose) of NO2, and an O2 sensor configured to measure a concentration (i.e. content or dose) of O2. the sensor(s) are arranged so as to carry out concentration measurements within the gas analysis line. said at least one internal passage and / or the gas analysis line comprise conduits, passages, pipes or the like. the microprocessor control means comprise (at least) one electronic card. the control means comprise one (or more) microprocessors arranged on the electronic card. the microprocessor(s) implements one or more algorithms, in particular for processing flow measurements, managing displays or controlling valve means. The graphical display is part of a GUI or graphical user interface, the graphical display is a color display. the graphic display is configured to detect a contact of a user's finger pressing on the surface of the graphic display. The graphic display includes a touch screen. it includes selection means for fixing, adjusting or selecting a desired quantity of NO, i.e. an NO content or concentration. the selection means comprise at least one key or button, in particular a virtual key displayed on the graphic display. the valve means comprise at least one solenoid valve, preferably one or more proportional and / or all-or-nothing (ON) solenoid valves. - the valve means, in particular the solenoid valve(s), are controlled by the pilot means to control the flow of gas within said at least one internal passage.

[0012] Depending on the embodiment considered, the NO-based gas administration installation of the invention may comprise one or more of the following features: the flow measurement device is configured to measure at least one gas flow rate corresponding to the flow rate of oxygen-containing gas supplied by the medical ventilator to the patient circuit. the flow measuring device is arranged on the patient circuit, between the medical ventilator and the connection site of the NO supply device to said patient circuit. it comprises a medical ventilator, i.e. a ventilatory assistance device, for supplying an oxygen-containing gas to the patient circuit, preferably a gas with an O2 content of at least about 21% vol., typically air or an NO / N2 mixture. the flow measurement device is configured to measure at least one gas flow rate corresponding to the flow rate of oxygen-containing gas supplied by the medical ventilator to the patient circuit. the medical ventilator is in fluid communication with the patient circuit to supply it with the oxygen-containing gas, such as a respiratory gas containing at least about 21% vol. of oxygen, in particular air or an N2 / O2 mixture. The medical ventilator is a respiratory assistance device providing gas at a given pressure or flow rate, which can be constant or variable. alternatively, the medical ventilator is a HFO (High Frequency Oscillations) type ventilator delivering the gas by high frequency oscillations, at least one gas source containing gaseous NO, in particular a NO / N2 gas mixture is fluidically connected to the NO supply device. the gas source(s) contains a NO / N2 gas mixture containing less than 2000 ppm by volume of NO, the remainder being nitrogen, preferably less than 1000 ppm by volume of NO, the remainder being nitrogen, preferably, the gas source contains a NO / N2 mixture containing from 250 to 900 ppm by volume of NO, the remainder being nitrogen, for example of the order of 450 or 800 ppm by volume of NO, the remainder being nitrogen. at least one gas source comprises one or more gas containers, in particular one or more pressurized gas cylinders. - the gas container(s) is / are equipped with a gas distribution tap with or without an integrated pressure regulator (RDI). - the fluid container(s) is (are) a pressurized gas cylinder containing, when full, a gas mixture, in particular NO / N2, at a pressure of at least 150 to 200 bar abs, or even at least 250 to 300 bar abs.

[0013] Depending on the embodiment considered, the patient circuit may comprise one or more of the following characteristics: - it includes an inspiratory branch and preferably an expiratory branch. - it comprises one (or more) flexible gas conduit, i.e. pipe, line, duct or the like, forming all or part of the inspiratory branch and possibly the expiratory branch. - the flexible gas line comprises at least two sections of pipe which connect to the flow sensor. - the connection to the flow sensor is made by means of fluid connection connectors, for example push-fit, screw-fit, bayonet or other connection. - it is supplied, in particular the inspiratory branch, with a NO / N2 mixture supplied by the gas supply device and with a respiratory gas containing at least approximately 20% vol. of oxygen, preferably at least approximately 21% vol., in particular air or an N2 / O2 mixture, supplied by the medical ventilator. - a gas humidifier arranged on the patient circuit, in particular on the inspiratory branch, preferably downstream of the site where the NO supply device is fluidically connected to the patient circuit, in particular to the inspiratory branch. - the expiratory branch forms all or part of a line for recovering gases expired by the patient. - the inspiratory branch and the expiratory branch of the expired gases are connected to a connecting piece, preferably a Y-piece. - the inspiratory branch of the patient circuit constitutes a gas supply line. - the inspiratory branch of the patient circuit is fluidically connected to an outlet port of the medical ventilator so as to recover and convey the gas delivered by the medical ventilator. - the expiratory branch of the patient circuit is fluidically connected to an inlet port of the medical ventilator so as to convey all or part of the gases exhaled by the patient to the medical ventilator.

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[0020] Generally speaking, within the scope of the invention: - “ppmv” means parts per million by volume, - “%vol.” means percentage by volume. - “NO” means nitrogen monoxide. - “NO2” means nitrogen dioxide. - “N2” means nitrogen. - “O2” means oxygen. - by "sensor" is meant a measuring device designed for and capable of and / or configured to measure and provide one or more signals or measurements, for example a flow sensor is a gas flow measuring device making it possible to measure and provide one or more gas flow signals or measurements. - the terms “concentration”, “dose” and “content” are considered equivalent. - the terms "means of / to / for" are considered to be completely equivalent and substitutable by the terms "device of / to / for", for example the terms "control means" can be replaced by "control device", the terms "valve means" can be replaced by "valve device", the "control means" can be replaced by "control device"... The invention will now be better understood thanks to the following detailed description, given for illustrative but non-limiting purposes, with reference to the appended figures among which: [Fig.l] represents an embodiment of a gas administration installation, i.e. a gas containing NO, comprising an NO supply apparatus according to the invention. [Fig.2] shows a diagram of an embodiment of the internal architecture of the NO supply device of the installation of [Fig.l]. [Fig.3] shows a diagram of a bad connection of the flow sensor of the installation of [Fig.l]. [Fig.4] shows an example of displaying incorrect connection alarm information. An embodiment of a gas administration installation 100 according to the invention is illustrated in [Fig.l]. Here it comprises two pressurized gas cylinders or gas sources 10 each containing a NO / N2 gas mixture typically containing between 100 and 2000 ppmv of NO (N2 remainder), namely here a NO / N2 gas mixture containing for example 450 or 800 ppmv of NO (N2 remainder), which supply with NO / N2 mixture, a device or apparatus for supplying, i.e. delivering, NO 1 making it possible to monitor / follow and control the supply of the NO / N2 gas mixture.

[0021] The gas cylinders 10 are fluidically connected to the NO 1 supply device, via gas supply lines 12, such as flexible pipes or conduits or the like, which may be equipped with devices for regulating and / or monitoring the gas pressure, such as a gas regulator 13, pressure gauges, etc. The gas supply lines 12 are connected to one or more gas inlets 2 of the NO 1 delivery device which supply an internal gas passage 6 (see [Fig. 2]) used to convey the gas within the NO 1 delivery device, i.e. into the housing of the NO 1 delivery device.

[0022] The NO 1 supply device also comprises an oxygen inlet 3 fluidically connected, via an oxygen supply line 11, such as a flexible pipe or the like, to an oxygen source, for example a pressurized oxygen cylinder or a hospital network, i.e. an oxygen supply pipe arranged in a hospital building.

[0023] The gas administration installation 100 further comprises a medical ventilator 50, i.e. a respiratory assistance device, which provides a flow of respiratory gas containing oxygen, typically of the order of at least approximately 21% oxygen, such as air or an oxygen / nitrogen mixture (N2 / O2), or even oxygen.

[0024] The medical ventilator 50 and the NO 1 supply apparatus of the gas administration installation 100 are in fluid communication with the inspiratory branch 21 of a patient circuit 20 which serves to convey the gas flow to the patient, which is formed by mixing the oxygen-based flow (i.e. air or NO / N2 mixture) coming from the medical ventilator 50 and the flow containing NO, i.e. the NO / N2 gas mixture, delivered by the NO 1 supply device.

[0025] More precisely, the NO 1 supply device delivers or injects the NO / N2 mixture, for example here at 450 or 800 ppmv of NO, into the gas supply line 21, via a conduit or injection line 23 connected to an NO outlet 5 of the device 1, so as to mix (at 24) the flow of NO / N2 with the flow of oxygen-based gas (with at least approximately 21% O2), e.g. air or an oxygen / nitrogen mixture, delivered by the medical ventilator 50 and conveyed by the inspiratory branch 21 of the patient circuit 20 so as to obtain a final mixture essentially containing NO at the desired dosage, nitrogen (N2) and oxygen (O2), and possibly unavoidable impurities (e.g. argon, CO2, NO2, ....), that is to say schematically a mixture gaseous NO / N2 / O2.

[0026] The inspiratory branch 21 further comprises a gas humidifier 30 arranged downstream of the site 24 where the injection of NO into the inspiratory branch 21 takes place. It makes it possible to humidify the gas flow, e.g. the NO / N2 / O2 gas mixture, before it is administered to the patient to be treated, by means of a respiratory interface 40, such as a tracheal intubation probe, a respiratory mask or the like.

[0027] A line for recovering gases exhaled by the patient is also provided, forming the expiratory branch 22 of the patient circuit 20. The inspiratory branch 21 and the expiratory branch 22 are connected to a connecting piece 25, such as a Y-shaped piece.

[0028] The inspiratory branch 21 is connected, upstream, fluidically to an outlet port 51 of the medical ventilator 50, such as a connector, fitting or the like, so as to recover and convey the oxygen-based gas, typically air or N2 / O2 mixture (containing approximately 21% O2) delivered by the medical ventilator 50, while the expiratory branch 22 conveying the exhaled gases is fluidically connected to an inlet port 52 of the medical ventilator 50, such as a connector, fitting or the like, so as to return to the medical ventilator 50 all or part of the flow of gases exhaled by the patient.

[0029] The expiratory branch 22 of the expired gases may comprise one or more optional components, such as for example a CO2 elimination device 35, i.e. a CO2 trap, such as a hot tank or other, making it possible to eliminate the CO2 present in the gases expired by the patient or a filter or other.

[0030] Flow rate measuring means 25, such as a flow rate sensor, for example of the mass, hot wire or pressure differential type, preferably a mass flow rate sensor, are arranged on the inspiratory branch 21, between the fan 50 and the humidifier 30, and are connected to the NO 1 delivery device, via a flow rate measuring line 26. This arrangement serves to measure the flow rate of gas delivered by the fan 50, such as air or an N2 / O2 mixture, or even oxygen, and circulating in the inspiratory branch 21, upstream of the connection site 24 of the injection conduit or line 23 where the NO / N2 / O2 gas mixture is made. This makes it possible to regulate the delivery of the NO flow (i.e. N2 / O2) more effectively by the NO 1 delivery device since the flow measurements made by the flow sensor 25 are returned, via the flow measurement line 26, to the control means of the NO 1 delivery device.

[0031] As shown diagrammatically in [Fig. 2], the NO 1 supply apparatus comprises, in a conventional manner, a rigid housing, for example made of polymer, crossed by an internal gas passage 6, such as a gas conduit or the like, for conveying the NO / N2 flow supplied by the gas supply line(s) 12 which is supplied by the NO / N2 mixture bottles 10. The internal gas passage 6 fluidly connects the gas inlet(s) 21 of the NO 1 supply apparatus to the injection line 23, via an NO 5 outlet of the apparatus 1, so as to convey the NO-based gas flow between them. Valve means 7, i.e. one (or more) valve devices, for example a solenoid valve or a plurality of solenoid valves arranged in parallel, preferably one or more proportional and / or all-or-nothing (solenoid) valves, are arranged on the internal gas passage 6 to control the gas flow circulating therein towards the injection line 24.

[0032] To do this, the valve means 7 are controlled by control means 8, i.e. one (or more) control devices, also arranged in the housing of the NO 1 supply apparatus, typically an electronic card comprising one (or more) microprocessor(s) 9, typically one (or more) microcontroller(s), implementing one or more algorithms. They may comprise other elements, such as one (or more) computer memory, such as a flash memory (not shown).

[0033] The control means 8 make it possible in particular to adjust or control the gas flow rate by controlling the valve means, typically to open or close this or these valves, to obtain a gas flow rate determined and / or calculated by the control means 8 from a value set / fixed by the user, and as a function of the gas flow rate, i.e. air, delivered by the ventilator 50 and measured by the flow rate sensor 25 arranged on the inspiratory branch 21 and connected to the NO 1 supply device, by the flow rate measurement line 26.

[0034] The internal gas passage 6 of the NO 1 supply apparatus may also comprise one or more flow meters (not shown) and / or a pressure regulator, such as a pressure reducer, (not shown) arranged upstream and / or downstream of the valve means 7, to determine the flow rate of NO-based gas circulating in the NO 1 supply apparatus. The flow meter may be of the pressure differential, hot wire or other type. It cooperates with the control means to provide them, again, with flow rate measurements of the NO / N2 flow, which measurements are processed by the control means 8 in order to ensure efficient delivery of NO as a function in particular of the flow rate of O2-based gas supplied by the medical ventilator 50.

[0035] Usually, the NO 1 supply device also comprises a graphical user interface or GUI comprising a graphical display 4, preferably a touch screen, i.e. a touch panel, used to display various information or data, icons, curves, alarms, etc., as well as virtual selection keys and / or blocks or windows, used in particular to make choices, selections or to enter information, such as desired values ​​(e.g. flow rate, NO dosage, etc.), or any other information or data useful to the healthcare personnel. Preferably, the display is in color but it can also be in black and white.

[0036] The control means 8 of the NO supply apparatus 1 comprising for example an electronic control card and a microprocessor control unit 9, typically a microcontroller or the like. The control means 8 make it possible to control or command all the electromechanical elements of the apparatus 1. More precisely, the control card preferably integrates the control unit and is configured to control and furthermore analyze the signals coming from the various components, such as the sensors...

[0037] The electrical power supply of the NO 1 supply apparatus, in particular of the components requiring electrical current to operate, such as the control means, the graphic display 4, etc., is conventionally provided by a source of electrical current and / or electrical power supply means (not shown), for example a connection to the mains current (110 / 220V) of the electrical cord and connection plug type, and / or one (or more) electrical power supply batteries, preferably rechargeable, and / or a current transformer. The electrical power supply of the medical ventilator 50 is provided in a similar manner, in particular by a connection to the mains current or an internal battery.

[0038] Finally, the installation 100 also comprises a gas sampling line 60 which fluidly connects the inspiratory branch 21 to the NO 1 supply device. It is fluidly connected (at 61) to the gas supply line 21, between the humidifier 30 and the junction piece 25, i.e. the Y-shaped piece, typically in the immediate vicinity of the junction piece 25, and also to an inlet port 62 of the NO 1 supply device, for example a port 62 carried by a connector, fitting or the like, allowing the gas sampling line 60 to be connected, such as a flexible pipe or the like, to a gas analysis line 111 provided with sensors 112 of an internal gas analyzer 110, as detailed below.

[0039] The gas sampling line 60 makes it possible to take gas samples from the inspiratory branch 21 of the patient circuit 20 and convey them to the NO 1 supply device where they are analyzed in an internal gas analyzer, i.e. within a gas analysis line comprising measuring means, such as one or more sensors, typically one or more electrochemical cells for example, electrically connected to the control means 8, in order to verify the conformity of the analyzed gas samples. In particular, it is appropriate to verify that the composition of the final gas is consistent with that of the desired NO / N2 / O2 gas mixture to be administered to the patient, in particular to ensure that it does not contain an excessive quantity of toxic NO2 species, that its oxygen content is not hypoxic, that it does not contain too high a NO2 content and that its NO content corresponds to the desired dosage, i.e.dose of NO to be administered by inhalation which is usually chosen by the healthcare personnel, i.e. doctor or similar. This compliance check is traditionally carried out using dedicated measuring means, typically NO2, NO and O2 sensors, for example electrochemical cells or similar, which themselves must be calibrated periodically.

[0040] [Fig.3] schematizes a bad connection of the flow sensor of the flow measuring device 25 of the installation 100 of [Fig.l].

[0041] As can be seen, the flow measurement device 25 comprises a tubular body 25a traversed by an internal channel and comprising connection means mechanical and fluidic 27, such as connectors or the like, making it possible to secure said tubular body 25a to the inspiratory branch 21 of the patient circuit 20, namely upstream and downstream sections 21a, 21b of said inspiratory branch 21, which are also provided with complementary mechanical and fluidic connection means 27, such as connectors or the like, and have just connected at the inlet (i.e. upstream) and outlet (i.e. downstream) of the tubular body 25a of the flow measurement device 25.

[0042] In [Fig. 3], the right part (Part A) illustrates a correctly connected flow measuring device 25, i.e. in the direction of circulation of the gas flow towards the humidifier 30 which is located downstream. This correct connection is illustrated by the “arrow” shaped marking 28 affixed to the tubular body 25a of the flow measuring device 25 which is in the normal direction of circulation of the flow.

[0043] Conversely, the left part (Part B) illustrates a flow measurement device 25 incorrectly connected, i.e. in reverse with respect to the direction of circulation of the gas flow. In this case, it can be seen that the “arrow” shaped marking 28 indicates the opposite direction to the normal direction of circulation of the flow.

[0044] As already explained, making an incorrect connection of the flow measurement device 25, i.e. in the opposite direction to the flow circulation, can be dangerous for the patient because it generates erroneous flow measurements which are transmitted to the control means of the NO 1 supply apparatus where they are used to calculate the quantity of NO to be supplied. However, if these measurements are incorrect, then the calculated quantity of NO to be supplied will also be incorrect, therefore the concentration of NO supplied to the patient will not correspond to the desired dosage, i.e. set by the doctor or the like.

[0045] In order to avoid this problem, according to the invention, the control means 8, which are connected to the flow rate measuring device 25, are configured to process the flow rate measurement(s) coming from the flow rate measuring device 25 in order to detect any possible inversion of the direction of connection of the flow rate measuring device 25 to the patient circuit 20, in particular to the inspiratory branch 21, and to display on the graphic display 4 of the apparatus 1, a visual alarm in the event of detection of such an inversion of the direction of connection of the flow rate measuring device 25, as illustrated in Part B of [Fig.3].

[0046] For example, a new flow rate value from the flow sensor 25 is received at a given frequency, for example every 10 msec. A bad orientation of the flow sensor 25 is detected if the moving average of the flow rate is less than a given threshold value during a determined time interval, for example less than -100 ml / min for 4 seconds.

[0047] The visual alarm displayed on the graphic display 4 of the device 1 includes an information message mentioning a reversal of the direction of connection of the flow measuring device 25.

[0048] When this message is displayed, the nursing staff immediately knows that the flow measuring device 25, i.e. the flow sensor, has been incorrectly connected and can therefore remedy the problem by correctly connecting the flow measuring device 25 to the inspiratory branch 21, i.e. in the correct direction, as illustrated in Part A of [Fig.3].

[0049] The detection of inversions is done either when the device is on standby, i.e. in "standby", just before the start of a treatment that one wishes to begin, or in the event of an inversion that occurs during treatment, after disconnecting and reconnecting the flow sensor.

[0050] [Fig.4] represents an example of display 4.1 of such an information message, that is to say a visual alarm, mentioning a reversal of the direction of connection of the flow measuring device 25. Preferably, the display 4.1 is done within a window 4.2, also called 'pop-up' in English, appearing on the graphic display 4.

[0051] The display 4.1 on the graphic display 4 of this or these pieces of information is done as soon as an inversion is detected by the control means 8.

[0052] The information, i.e. the alert message or other, is preferably stored in the storage means of the device 1, such as a flash memory or any other type of computer memory.

[0053] The alert message may include alphanumeric characters, an alert icon, a graphical representation or the like, for example a graphical representation of a portion of the patient circuit 20 and the flow measurement device 25, as illustrated in [Fig.4].

[0054] When the user sees the information(s) appear, i.e. displayed, on the graphic display 4, he understands that an incorrect connection has been made and can therefore correct this error by correctly connecting the flow measurement device 25.

[0055] The user can further confirm having received the alert message 4.1 by confirming its receipt by pressing a key 4.3 of the “OK” type or similar, displayed in the window 4.2 or elsewhere, as illustrated in [Fig.4].

[0056] More generally, the display on the display screen 4 can be in color or in black and white, depending on what is selected by the user in the menus of the device 1.

[0057] The control means of the device 1 are further configured to prevent any launch, i.e. any start-up, of treatment, with supply of a flow of NO, in the event of detection of a reversal of the direction of connection of the flow measurement device 25. To do this, the control means control the valve means 7 to prevent or block the supply of any flow of NO through said at least one internal passage 6, i.e. the main gas circuit of the device 1.

[0058] Furthermore, in the event of detection of a reversal of the direction of connection of the flow measurement device 25, the apparatus 1, in particular the control means, can also propose or trigger an emergency dosing procedure, i.e. an emergency dosing, as described by EP3233171.

[0059] Generally speaking, the gas administration of the invention, such as that illustrated in [Fig.l], can be used to administer, via a mask or a tracheal intubation tube, nitric oxide (NOi), i.e. the final mixture obtained NO / O2 / N2, to one or more persons, i.e. patients, needing it to treat their pulmonary pathology, typically one or more patients suffering from acute pulmonary arterial hypertension, in particular to operate a dilation of their pulmonary vessels and / or an increase in their oxygenation by improving pulmonary gas exchange, in particular to treat Pulmonary Arterial Hypertension of the Newborn or PPHN, Acute Respiratory Distress Syndrome or ARDS observed mainly in adults, or pulmonary hypertension (PH) in cardiac surgery in adults or children.

Claims

Claims

1. Gas administration installation (100) for supplying a gas containing NO to a patient comprising: - an NO supply apparatus (1) comprising at least one internal passage (6) for conveying a flow of gas containing NO, control means (8) with a microprocessor (9), and a graphic display (4), - a patient circuit (20) to which said NO supply apparatus (1) is fluidically connected to supply the gas containing NO to said patient circuit (20), and - a flow measurement device (25) fluidically connected to the patient circuit (2) to measure at least one gas flow rate and connected to the control means (8) of the NO supply apparatus (1) to provide said control means (8) with at least one flow measurement,characterized in that the control means (8) are configured to: - process said at least one flow measurement coming from the flow measurement device (25) to detect a reversal of the direction of connection of the flow measurement device (25) to the patient circuit (20), and - display (4.1) on the graphic display (4), a visual alarm in the event of detection of a reversal of the direction of connection of the flow measurement device (25).,

2. Installation according to claim 1, characterized in that it comprises storage means and the graphic display (4) is configured to display an information message mentioning a reversal of the direction of connection of the flow measuring device (25) stored within the storage means as a visual alarm (4.1).

3. Installation according to claim 1, characterized in that the flow measuring device (25) comprises a flow sensor or a pressure sensor, preferably a mass flow sensor, hot wire or pressure differential.

4. Installation according to claim 1, characterized in that the control means (8) of the NO supply apparatus (1) are configured to detect a reversal of the direction of connection of the flow measuring device (25) to the patient circuit (20) by determining a negative gas flow from said at least one flow measurement coming from the flow measuring device (25).

5. Installation according to claim 1, characterized in that it further comprises a medical ventilator (50) for supplying a gas containing oxygen to the patient circuit (20).

6. Installation according to claims 1 and 5, characterized in that the flow rate measuring device (25) is configured to measure at least one gas flow rate corresponding to the flow rate of gas containing oxygen supplied by the medical ventilator (50) to the patient circuit (2).

7. Installation according to claims 1 and 5, characterized in that the flow measuring device (25) is arranged on the patient circuit (2), between the medical ventilator (50) and the connection site of the NO supply device (1) to said patient circuit (2).

8. Installation according to one of claims 1 or 4, characterized in that the control means (8) of the NO supply apparatus (1) are configured to control valve means (7) arranged on said at least one internal passage (6) of the NO supply apparatus (1) to prevent or block the supply of a flow of gas containing NO through the internal passage (6) in the event of detection of a reversal of the direction of connection of the flow measuring device (25).

9. Installation according to claim 1, characterized in that it further comprises at least one gas source (10) containing gaseous NO fluidly connected to the gas supply apparatus (1) to supply it with a gas containing NO.

10. Installation according to claim 9, characterized in that said at least one gas source (10) contains a NO / N2 gas mixture, in particular one or more gas cylinders containing a NO / N2 gas mixture containing less than 2000 ppmv of NO, the remainder being nitrogen.

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