Storage cartridge for a NO / nitrogen mixture and associated gas supply installation

Abstract

Title of the invention Storage cartridge for a NO / nitrogen mixture and associated gas supply installation The invention relates to a storage cartridge (1) for a pressurized NO / N2 gas mixture comprising a main body (11) with an internal volume (12) for storing the gas and a distribution valve (2) for controlling the gas outlet. The internal volume (12) of the main body (11) is less than 1000 mL. The NO concentration in the NO / N2 gas mixture is between 15000 and 25000 ppmv. The gas pressure in the internal volume (12) is less than 15 bar, measured at 23°C. Installation (100) for supplying gas to a patient comprising such a gas cartridge (1), an NO delivery device (50) supplied by the gas cartridge (1), and a medical ventilator (60) supplying a patient circuit (61) with an inspiratory branch (61A) supplied by the NO delivery device (50).Use to treat patients with pulmonary hypertension or hypoxia. Abstract figure: Fig. 1.

Description

Title of the invention: Cartridge for storing a NO / nitrogen mixture and associated gas supply installation

[0001] The invention relates to a cartridge for storing, i.e. conditioning, a gaseous mixture of nitric oxide and nitrogen (NO / N2) designed to be fluidically connected to a device for delivering gaseous NO for injecting the gaseous mixture NO / N2 into the ventilatory circuit of a medical ventilator, i.e. a medical apparatus for administering gas to a patient, as well as the use of such a cartridge for conditioning a gaseous mixture NO / N2, as well as an installation for supplying gas to a patient comprising such a cartridge supplying a NO delivery device and a medical ventilator supplied with gaseous mixture NO / N2 by said NO delivery device.

[0002] Nitric oxide or NO is a gas which, when inhaled, dilates the pulmonary vessels and increases oxygenation by improving gas exchange. The properties of NO 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 in cardiac surgery or others, as taught in particular by EP-A-560928, EP-A-1516639 or US-A-10,201,564.

[0003] In general, the NO / N2 mixture containing a small amount of gaseous NO (i.e. a few tens or hundreds of ppm by volume) is injected, via a gaseous NO delivery device, into a gaseous flow containing oxygen (O2) circulating in the ventilatory circuit of a medical ventilator and which is then inhaled by the patient. Typically, the oxygen-containing gas is typically an N2 / O2 mixture or air, such as medical-grade air. Furthermore, the concentration of NO inhaled by the patient, which corresponds to a dosage, is determined by the physician or the like. In general, the concentration of NO in the gas inhaled by the patient is between 1 and 80 ppm by volume (ppmv), depending on the population treated, i.e. newborns or adults, and therefore the disease to be treated.

[0004] Thus, US-A-5,558,083 describes a NO delivery device associated with a mechanical ventilator supplying a respiratory interface delivering the NO to the patient, for example a respiratory mask, a tracheal intubation probe or the like.

[0005] The NO delivery device is fluidically connected and supplied by one or more gas cylinders containing the N2 / NO mixture whose NO concentration is often between 200 and 1000 ppmv.

[0006] Such gas bottles are in the form of metal cylinders or warheads, typically made of steel or aluminum alloy, several tens of centimeters high, generally around 1 m high, containing the NO / N2 mixture at high pressure, i.e. at several tens, or even hundreds of bars, for example around 140 to 230 bars.

[0007] Furthermore, in order to provide a pressure compatible with the NO delivery device, these cylinders are always equipped with a pressure regulator allowing the pressure present in the cylinder to be lowered to a lower pressure, called the service pressure, at the outlet of the regulator. The pressure regulator is itself a metal part, for example made of stainless steel. N2 / N0 cylinders are therefore large and / or bulky, which can pose a problem when using them in critical care rooms which can be cramped and already very cluttered by other medical equipment. In addition, the large volumes of gas contained in these N0 / N2 cylinders also lead to storage constraints, requiring these cylinders to be stored in dedicated and ventilated rooms, which poses a problem of space and logistics within hospital buildings.

[0008] The dimensions and architecture of cylinders equipped with pressure regulators and the volumes of gas stored therein inevitably result in a significant weight, typically a weight of around 20 kg per cylinder. It is understood that such weights create logistical and handling difficulties for healthcare personnel, particularly during intra-hospital transfers. Moreover, injuries have already been reported, such as cylinders falling onto users' feet during cylinder replacement procedures (i.e. empty versus full), back pain after lifting, carrying or handling full cylinders, etc.

[0009] Furthermore, any treatment involving NO is critical and cannot tolerate a sudden interruption of the therapy, at the risk of observing a rebound effect in the patient. Therefore, any NO delivery device is generally connected to 2 identical gas cylinders. When one cylinder becomes empty, the NO delivery device automatically switches to the full cylinder, which minimizes the risk of interruption but aggravates the aforementioned problem of congestion in cramped hospital environments, such as critical care rooms.

[0010] Finally, using gas cylinders having a very high internal pressure, for example 140 bars or more, requires trained personnel, in particular in the handling of pressure regulators, which complicates the implementation of NO-based therapy outside intensive care rooms, for example in light care rooms, but also leads to higher logistical costs, in particular with regard to transporting the cylinders from the production site to the place of use, typically a hospital.

[0011] US-A-10,213,572 proposes to replace conventional gas bottles, which are heavy and bulky, by a cassette containing a small, airtight glass flask containing liquid nitrogen peroxide N2O4. A striker releases the N2O4 by breaking the flask. Upon heating, the N2O4 dissociates into NO2 which, when brought into contact with solid ascorbic acid or the like, is transformed into NO which can then be delivered in the form of NO to treat a patient. However, this type of cassette creates logistical, storage, handling and other problems, and risks due to the use of toxic chemicals. In addition, their cost is high.

[0012] In view of this, there is a need to be able to implement NO / nitrogen mixtures in a hospital environment without encountering all or part of the aforementioned problems and drawbacks, in particular to be able to do without conventional gas cylinders which are particularly heavy and bulky, or cassettes whose operation is based on dangerous and expensive chemical products.

[0013] A solution according to the invention then concerns a cartridge for storing a NO / N2 gas mixture under pressure comprising: - a main body comprising an internal volume for containing the gas mixture, and - a gas distribution valve to control the exit of the gas mixture from the internal volume of the main body,

[0014] characterized in that: - the internal volume of the main body is less than or equal to 1000 mL, - the NO concentration in the NO / N2 gas mixture is between 15,000 and 25,000 ppmv, and - the gas pressure in the internal volume of the main body is less than 15 bar, measured at 23°C.

[0015] In the context of the invention: - the pressure is expressed in “absolute bar”, abbreviated “bar”, - the volume is given in water equivalent by being expressed in milliliters, abbreviated mL, - NO contents are expressed in parts per million by volume, abbreviated “ppmv”.

[0016] Depending on the embodiment considered, the storage cartridge of the invention may comprise one or more of the following characteristics: - the main body is made of aluminum alloy. - the main body comprises a wall having a thickness of between 0.1 and 0.5 mm. the main body is elongated along a main axis (AA). The main body has a height between 15 cm and 30 cm. the main body has an ogival shape. the main body is closed at its upper end, by a cover, preferably a cover crimped or welded to the part of the main body in the shape of an ogive. the dispensing valve is carried by the cover. The dispensing valve is located in the center of the lid. the main body extends between a bottom and an upper end to which the cover is attached. the dispensing valve, the cover and the main body are coaxial. the cover is made of aluminum alloy the internal volume of the main body is between 500mL and 1000mL, preferably less than 900mL. the internal volume of the main body is less than or equal to 850 mL, preferably less than or equal to 800 mL. it weighs less than 1 kg, preferably between 150 and 750 grams. the NO concentration in the NO / N2 gas mixture is between 15,000 and 25,000 ppmv, preferably at least 20,000 ppmv. the NO concentration in the NO / N2 gas mixture is between 20,000 and 24,000 ppmv, preferably between 22,500 and 23,500 ppmv, preferably at most 23,000 ppmv. the NO / N2 gas mixture consists of carbon monoxide (NO) molecules and nitrogen (N2) molecules. However, the presence of unavoidable impurities resulting from the manufacturing process of the gas mixture, in particular water vapor and / or oxygen, in negligible quantities, typically less than 3 to 5 ppmv, cannot be excluded. the gas pressure in the internal volume of the main body is less than or equal to 13 bar, measured at 23°C, preferably less than or equal to 12 bar, more preferably less than or equal to 11.5 bar. the gas pressure in the internal volume of the main body is a maximum of 11.5 bar measured at 23°C. the main body comprises a bottom, an intermediate tubular portion and an upper end closed by a cover carrying the gas distribution valve, preferably the intermediate tubular portion is substantially ogive-shaped. the cover is crimped or welded to the intermediate tubular portion. - the cover has a circular periphery. - the cover is shaped to have a central ridge, i.e. a protrusion projecting outwards, i.e. above the cover, comprising a central passage and defining an internal compartment. - the central passage of the central bead communicates with the internal compartment of said central bead. - the distribution valve comprises an exhaust channel associated with a seat element, said exhaust channel being movable in axial translation within the central passage of the central bead, and the seat element cooperating with a sealing element to operate a gas seal and prevent any passage of gas from the internal volume of the cartridge to the exhaust channel. - the sealing element is a seal, preferably flat, such as a flat O-ring. - the exhaust channel and the seat element are integral with each other, typically fixed to each other. - the seat element is normally pushed towards the sealing element by elastic means. - the seat element is normally pushed towards the sealing element by elastic means via a diffuser element arranged between the seat element and the sealing element. - the elastic means presses on the diffuser element to push it back towards the seat element. - the elastic means is a cylindrical spiral spring. - the seat element is movable in translation in a support part forming a sleeve housing the seat element and the elastic means, and preferably the diffuser element. - the support piece is housed and fixed in the internal compartment of the central bead. - the exhaust channel comprises a free downstream end located outside the central bead and an upstream end located in the internal compartment of the central bead and cooperating with the seat element.

[0017] The present invention also relates to a use of a gas cartridge according to the invention, having an internal volume of less than 1000 mL, preferably less than 900 mL, for storing a NO / N2 gas mixture having an NO concentration of between between 15,000 and 25,000 ppmv, typically between 20,000 and 23,500 ppmv, at a pressure below 15 bar, typically below 11.5 bar, measured at 23°C.

[0018] Furthermore, the present invention also relates to an installation for supplying gas to a patient comprising: - at least one source of NO containing a NO / N2 gas mixture, - an NO delivery device, supplied with NO / N2 gas mixture by said at least one NO source, - an inspiratory branch of a patient circuit supplied with NO / N2 gas mixture by the NO delivery device, and - a medical ventilator in fluid communication with the inspiratory branch to supply said inspiratory branch with a respiratory gas containing at least 21% oxygen, preferably air or an oxygen / nitrogen mixture,

[0019] characterized in that the NO source is a gas cartridge according to the invention having an internal volume of less than 1000 mL, preferably less than 900 mL, for storing a NO / N2 gas mixture having an NO concentration of between 15,000 and 25,000 ppmv, typically between 20,000 and 23,500 ppmv at a pressure of less than 15 bar, typically less than 11.5 bar, measured at 23°C.

[0020] 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. 1] represents an embodiment of a NO / N2 mixture storage cartridge according to the invention, - [Fig.2] shows schematically an embodiment of a gas distribution valve equipping the gas cartridge of [Fig.l], shown in the closed position, - [Fig.3] shows the gas distribution valve of [Fig.2], in the open position, - [Fig.4] shows schematically an embodiment of an installation for delivering NO to a patient incorporating a NO / N2 mixture storage cartridge according to the invention, such as that of [Fig.l], - [Fig.5] schematizes an embodiment of the seat element of the gas distribution valve of [Fig.2] and [Fig.3], and - [Fig.6] shows a schematic of an embodiment of the diffuser element of the gas distribution valve of [Fig.2] and [Fig.3].

[0021] [Fig.l] represents an embodiment of a storage cartridge 1 for NO / N2 gas mixture according to the invention. The gas cartridge 1 comprises a main body 11 forming a peripheral envelope defining an internal compartment or volume 12 used to contain and store the NO / N2 gas mixture.

[0022] The main body 11 is elongated along the axis AA of the cartridge 1. It has a bottom 13, for example a flat or curved surface, an intermediate tubular portion 10 substantially in the shape of an ogive and an upper end 10a closed by a cover 21 carrying a distribution valve 2 or gas dispensing valve used to control the exit of the gas mixture from the internal volume 12 of the main body 11. The distribution valve 2 is provided with an exhaust channel 22 for conveying the gas. The structure and operation of the distribution valve 2 are detailed below.

[0023] The cover 21 is preferably hermetically crimped or welded to the periphery 14 of the intermediate tubular portion 10, at its upper end 10a. In the event of crimping the cover 21 onto the upper periphery 14 of the main body 11, a perfect seal is achieved between them thanks to a flat O-ring 218, i.e. a circular flat seal, inserted between these elements, as visible in [Fig.2]. Furthermore, the bottom 13 is preferably hermetically welded to the lower end 10b of the main body 11.

[0024] The main body 11 forming the peripheral casing of the gas cartridge 1 is metallic, preferably an aluminum alloy, and has a wall having a thickness of a few tenths of a millimeter, for example between approximately 0.1 and 0.5 mm. The same applies to the cover 21 and the bottom 13.

[0025] The gas cartridge 1 may contain in its internal volume 12 a NO / N2 mixture under low pressure, that is to say not exceeding one or a few tens of bar, typically less than 15 bar. The internal volume 12 of the gas cartridge 1 is less than 1000 mL, preferably less than 900 mL, or even less than 800 mL, for example a volume of the order of 790 mL.

[0026] Preferably, the main body 11 of the gas cartridge 1 has a height H of between 10 cm and 30 cm, measured between the two upper 10a and lower 10b ends, i.e. at the level of the bottom 13.

[0027] Due to its simple design, the gas cartridge 1 can be manufactured on a large scale, which has an advantage in terms of ease of production and therefore cost.

[0028] [Fig.2] and [Fig.3] diagram the architecture and operation of the valve of gas distribution 2 above gas cartridge 1.

[0029] The distribution or dispensing valve 2 is carried by the circular-shaped cover 21 which is formed from a shaped wall or envelope 211, that is to say including successive specific portions or zones, in particular a rounded outer periphery 212, a central bead 213 crossed by the exhaust channel 22, and a lateral boss 214 arranged at the base of the central bead 213.

[0030] The central bead 213 forms a protuberance or bulge with a cylindrical periphery and projecting axially (axis AA), on the external surface of the cover 21 while being directed outwards, i.e. upwards on [Fig.l], i.e. projecting away above the cover 21 along the axis AA. The central bead 213 defines an internal compartment 213A. The central bead 213 is formed by deformation and / or shaping of the part forming the cover 21, such as a metal disc.

[0031] The metal cover 21, preferably made of aluminum alloy, has a thickness of a few tenths of a millimeter, for example from 0.1 to 0.5 mm. The central bead 213 located in the center of the cover 21 has a through recess or central passage 217, located in its center, housing the exhaust channel 22 which is in the form of a hollow conduit 221. The exhaust channel 22 and the cover 21 are coaxial, and moreover also arranged coaxially (axis AA) on the body 11 of the gas cartridge 1.

[0032] The exhaust channel 22 comprises a free downstream end 222 located on the outside and an upstream end 220 located in the internal compartment 213A of the central bead 213. The free downstream end 222 comprises a gas outlet orifice, while the upstream end 220 comprises lateral gas inlet channels 220a through which the gas coming from the internal volume 12 of the cartridge 1 can enter the hollow conduit 221 to then circulate therein towards the gas outlet orifice, as visible in [Fig.3].

[0033] The exhaust channel 22 comprises, at its upstream end 220 extending or located in the internal compartment 213A of the central bead 213 of the cover 21, a seat element 26. In other words, the seat element 26 is located in the internal compartment 213A of the central bead 213 of the cover 21. According to one embodiment, the seat element 26 is here in the form of a cylindrical body 261 comprising a central recess 263 including a blind bottom.

[0034] The exhaust channel 22 is secured to the seat element 26, for example, by force-fitting onto a shoulder 262, by welding or any other technique. According to another embodiment, the exhaust channel 22 and the seat element 26 may be formed from a single piece.

[0035] The exhaust channel 22 is able to translate in the central passage of the central bead 213 of the cover 21 towards the internal compartment 213A of the central bead 213. The exhaust channel 22 and the seat element 26 thus form an assembly or system for controlling the gas outlet / release which is axially movable (axis AA). Indeed, the front face 261 of the seat element 26 ensures, when it is in contact with a sealing element, such as a flat O-ring 23, arranged in the bottom 216 of the central bead 213, a fluid seal. between the seat element 26 and the sealing element 23, to then prevent any gas from escaping from the cartridge 1, as illustrated in [Fig.2] and detailed below. Conversely, when the front face 261 of the seat element 26 is no longer in contact with the sealing element 23, a gap is created between them, i.e. a break in the seal, which allows the gas to pass and enter the hollow conduit 221 and then circulate therein towards the gas outlet orifice.

[0036] Furthermore, a tubular support piece 24, preferably of cylindrical shape, forms a sleeve 241 having an outer wall 242 which is itself cylindrical. The support piece 24 is inserted into the internal compartment 213A of the central bead 213 formed in the envelope 211 of the cover 21, that is to say in the internal part of the central bead 213 of the cover 21.

[0037] More precisely, a portion of the outer wall 242 of the sleeve 241 comes into contact with an internal lateral portion 215 of the central bead 213 of the cover 21. The support piece 24 is then held in position by a lateral boss 214 obtained by radial deformation oriented towards the axis AA, that is to say towards the interior of the internal compartment 213A of the central bead 213, of a portion of the envelope 211 or wall located at the base of the central bead 213 of the cover 21.

[0038] In other words, the central bead 213 comprises, at its base 233, a lateral boss 214 making it possible to retain the support piece 24 in a fixed position in the internal compartment 213A of the central bead 213, by cooperating with a shoulder 224 located on the external wall of the tubular support piece 24. The lateral boss 214 corresponds to a depression or a deformation of the peripheral wall of the central bead 213 (at its base 233) which is directed towards the inside of the internal compartment 213A of the central bead 213, that is to say that the internal wall of the internal compartment 213A of the central bead 213 forms, at its base 233, an annular expansion projecting into the internal compartment 213A and cooperating with the shoulder 224 located on the external wall of the tubular support part 24.

[0039] The tubular support piece 24 also forms a sleeve around the seat element 26 located at the internal end of the exhaust channel 22 so that, during translations of the exhaust channel 22 in the central passage of the central bead 213 of the cover 21, said seat element 26 which is integral with the exhaust channel 22, can also translate at the same time within the sleeve formed by the tubular support piece 24, that is to say in the housing or internal volume 244 located at the center of the tubular support piece 24, as visible in [Fig.3].

[0040] Furthermore, the support piece 24 comprises an annular end 243 which presses on a sealing element, such as a flat O-ring 23 (i.e. annular) arranged in the internal bottom 216 of the central bead 213 and passed coaxially by the exhaust channel 22. In other words, the annular end 243 of the support piece 24 is also coaxial with the exhaust channel 22 and the O-ring 23, i.e. the sealing element, so that the O-ring 23 is sandwiched and compressed between the annular end 243 of the support piece 24 and the internal bottom 216 of the central bead 213 of the cover 21.

[0041] The sealing element, such as a flat O-ring 23, is therefore held in position by the support part 24 forming a sleeve, while the exhaust channel 22 can slide in its center which is hollowed out, i.e. a ring-shaped seal.

[0042] Furthermore, the seat element 26 is extended by a diffuser element 27 which can also slide in the internal volume 244 of the support part 24. This diffuser element 27 is of substantially cylindrical shape and has a neck 271 crossed in its center by a central channel 272. The central channel 272 then forms a fluid connection between the internal volume 244 of the support part 24 and an internal chamber 28 located between, on the one hand, the external surface 262 of the seat element 26 and the internal surface 247 of the support part 24 and, on the other hand, between the O-ring 23 and the diffuser element 27.

[0043] As visible in [Fig.2] and [Fig.3], the diffuser element 27 is also located in the internal compartment 213A of the central bead 213 of the cover 21.

[0044] According to one embodiment, the diffuser element 27 may be in the form of a tubular structure with a neck 271 and openings 272 for the gas, as illustrated in [Fig.6]. The neck 271 of the diffuser element 27 which is oriented towards the internal volume 12 of the cartridge 1, that is to say which projects axially (AA) towards the interior of the cartridge 1, makes it possible to receive and maintain in position one of the ends of an elastic means 25, namely here a cylindrical spring, which is housed and compressed between the diffuser element 27 and the bottom 246 of the support part 24.

[0045] The spring 25 normally pushes the diffuser element 27 towards the seat element 26 so as to ensure a fluid seal between said seat element 26 and the O-ring 23, as illustrated in [Fig.2].

[0046] The bottom 246 of the support part 24 is also crossed by an axial channel or passage 245. There is therefore a fluid communication between the axial passage 245 and the internal volume 244 of the support part 24, the central channel 272 of the diffuser element 27 and the internal chamber 28 allowing the gas flow, i.e. NO / N2 gas mixture, to circulate through these elements before leaving the internal volume 12 of the cartridge 1 when the gas is used, i.e. is sent to a ventilation circuit 61 of the fan 60 via an NO delivery device 50, as shown diagrammatically in [Fig.4].

[0047] More precisely, in the so-called “closed” or “rest” configuration illustrated in [Fig.2], the spring 25 pushes back the diffuser element 27 and consequently also the seat element 26 so that the front face 261 of said seat element 26 comes to compress the flat O-ring 23 and thus ensures a perfect fluid seal between the internal chamber 28 of the support part 24 and the hollow internal conduit 221 of the exhaust channel 22.

[0048] In this so-called “closed” configuration, no gas is delivered by the hollow internal conduit 221 of the exhaust channel 22. In other words, the gas contained in the internal volume 12 of the gas cartridge 1 is in fluid communication with the axial channel or passage 245 and the internal volume 244 of the support part 24, and diffuses to the internal chamber 28 but cannot escape into the hollow internal conduit 221 of the exhaust channel 22 via the lateral gas inlet channels 220a.

[0049] Conversely, [Fig.3] illustrates the valve 2 in the so-called “open” configuration in which gas is delivered through the hollow internal conduit 221 of the exhaust channel 22.

[0050] In order to move the valve 2 from the so-called "closed" configuration of [Fig.2] to the so-called "open" configuration of [Fig.3], it is sufficient to apply to the free end 222 of the exhaust channel 22, a mechanical force forcing said exhaust channel to perform an axial translation along the axis AA in the direction of the cartridge 1 so that the exhaust channel 22 slides in the central passages of the central bead 213 of the cover 21 and of the flat O-ring 23.

[0051] In other words, by applying an external force to the free end 222 of the exhaust channel 22 aimed at pushing the tubular exhaust channel 22 towards the valve 2 and the cartridge 1, a release of the gas is obtained which can then pass into the lumen or hollow internal conduit 221 of the exhaust channel 22 and then exit through the outlet orifice which is located at the free end 222 of the exhaust channel 22.

[0052] The external force applied to the end 222 of the exhaust channel 22 may result from the insertion of the cartridge 1 into a specific housing 51 provided in the NO delivery device 50, which specific housing 51 comprises an actuating mechanism 52 (not detailed) cooperating with the gas distribution valve 2 of the gas cartridge 1 according to the invention, as shown diagrammatically in [Fig.4] to release the gas.

[0053] Due to the coupling existing between the exhaust channel 22 and the seat element 26, the seat element 26 also undergoes an axial translational movement on the axis AA, and then simultaneously pushes the diffuser element 27 back, generating a more pronounced compression of the cylindrical spiral spring 25, as visible in [Fig.3].

[0054] In doing so, the front face 261 of the seat element 26 then loses contact with the flat O-ring 23 (which remains in position, as in [Fig.2]), which causes a break in the fluid seal between them.

[0055] The internal chamber 28 is then in fluid communication not only with the hollow internal conduit 221 via the lateral gas inlet channels 220a of the exhaust channel 22 but also with the central channel 272 of the diffuser element 27, the internal volume 244 and the channel 245 of the support part 24. A circulation of gas can then be established through these different elements and in the direction of the gas outlet orifice carried by the free end 222 of the exhaust channel 22, as illustrated in [Fig.3].

[0056] In [Fig.3], the arrows diagram the circulation of gas from the internal volume 12 of the cartridge 1 and through the distribution valve 2.

[0057] The gas contained in the internal volume 12 of the gas cartridge 1 then diffuses via the internal chamber 28 to the hollow internal conduit 221 of the exhaust channel 22 through which it can then escape and be collected by the internal circuit 501 of the NO delivery device 50, as explained below and illustrated in [Fig.4].

[0058] In other words, the gas cartridge 1 provided with such a distribution valve 2 according to the invention is preferably intended to be inserted into a dedicated housing 51 of a NO 50 delivery device and to be held there in position in the so-called “open” valve 2 configuration via a mechanical constraint on the free end 222 of the exhaust channel 22 making it possible to push it back in translation and thus release the gas, i.e. the NO / N2 mixture contained in the cartridge 1.

[0059] Generally speaking, by way of example, a gas cartridge is designed having an internal volume 12 of the order of 790 ml containing a binary gas mixture NV NO pressurized to approximately 10 bar measured at approximately 23°C, said N2 / NO mixture containing approximately 23000 ppmv of NO, the remainder being nitrogen (and possibly unavoidable impurities in negligible quantities, such as water vapor or oxygen).

[0060] This is equivalent to 7900 ml of N2 / NO gas mixture at atmospheric pressure (i.e. 1 bar) and also corresponds to a volume of NO thus conditioned of approximately 180 ml (for the considered content of 23000 ppmv of NO).

[0061] For comparison, a gas cylinder conventionally used to condition N2 / NO mixtures can supply 1963 L of an N2 / NO mixture having an NO concentration of 800 ppmv. This corresponds to an available volume of NO of 1570 ml, i.e. a ratio of the available volume of NO of approximately 10.

[0062] The gas cartridge 1 according to the invention offers increased ease of use, simple logistics, less bulk, generates almost zero risks of use (injury in the event of a fall or handling or handling of dangerous products) for operators, i.e. healthcare personnel, and can be manufactured more simply, therefore at a much lower cost.

[0063] Furthermore, a gas cartridge 1 according to the invention also complies with the requirements and regulations on the transport and shipment of pressurized gases, which makes it possible to transport this type of cartridge 1 by a courier service. or mass delivery, such as FedEx or UPS. This also presents an undeniable advantage in terms of logistics and ease of operation in particular.

[0064] [Fig.4] schematizes an embodiment of an installation 100 for supplying, i.e. delivering, a gas containing NO to a patient incorporating a storage cartridge 1 of NO / N2 gas mixture according to the invention, for example the storage cartridge 1 of [Fig. 1].

[0065] This installation 100 for supplying gas to a patient P comprising the gas cartridge 1 according to the invention acting as a source of a NO / N2 gas mixture containing between 15,000 and 25,000 pppmv of NO (the remainder being nitrogen), arranged so as to supply, via its gas distribution valve 2, the upstream portion of the internal gas circuit 501 of an NO delivery device 50 designed to supply the NO / N2 gas mixture to the ventilation circuit 61 of a medical ventilator 60.

[0066] The gas cartridge 1 according to the invention is preferably housed in a dedicated housing 51 of the NO delivery device 50 comprising an actuating mechanism 52 (not detailed) cooperating with the gas distribution valve 2 of the gas cartridge 1 according to the invention, in particular by pressing on the end 222 of the exhaust channel 22 so as to push the tubular exhaust channel 22 towards the cartridge 1 and thus to allow the passage of gas from the internal volume 12 of the gas cartridge 1 according to the invention to said internal gas circuit 501 of the NO delivery device 50.

[0067] According to another embodiment, two (or more) identical gas cartridges 1 can be inserted into the dedicated housing 51 of the NO delivery device 50 to allow switching to a full cartridge 1 when the other cartridge 1 which is in use tends to empty, thus ensuring continuity of the therapy, i.e. avoiding any interruption in the supply of NO to the patient P. In other words, in this case, the two gas cartridges 1 are arranged in parallel with each other so as to be used alternatively. The empty cartridge can then be replaced, while the other delivers gas, i.e. the NO / N2 mixture.In this case, the dedicated housing 51 of the NO 50 delivery device is sized to accommodate several cartridges 1 and also comprises an actuating mechanism 52 dedicated to each cartridge, i.e. actuating mechanisms 52 cooperating with the gas distribution valve 2 equipping each gas cartridge 1.

[0068] In all cases, the fluid connection of the gas cartridge(s) 1 to the NO 50 delivery device is made in a sealed manner thanks to the use of sealing means, such as O-rings or the like.

[0069] In the NO delivery device 50, means 55 are provided for controlling the flow rate and / or the pressure of the gas, arranged on the internal gas circuit 501, making it possible to control or adjust the flow rate and / or the pressure of the gas conveyed by the internal gas circuit 501 of the NO delivery device 50, for example a pressure regulator, one or more control valves, such as solenoid valves, one or more calibrated orifices, one or more non-return valves, etc.

[0070] The means 55 for controlling the flow rate and / or the pressure of the gas are controlled by control means 53, also called a control unit, such as an electronic card with microprocessor(s) implementing one or more algorithms or any other suitable control system.

[0071] The gas flow of NO / N2 leaving the means 55 for controlling the flow rate and / or the pressure of the gas is conveyed by the downstream portion of the internal gas circuit 501 then an injection conduit 502, before being delivered into the inspiratory branch 61A of the patient ventilation circuit 61 fluidly connected to a medical ventilator 60, namely a respiratory assistance device providing a respiratory gas containing at least 21% oxygen, typically air or a nitrogen / oxygen mixture.

[0072] For ease of understanding, the respiratory gas supplied by the medical ventilator 60 is considered to be air. This air circulates in the inspiratory branch 61A from the ventilator 60 to a respiratory interface 63, such as a mask or a tracheal tube, supplying the patient P with the therapeutic mixture containing NO at the desired content.

[0073] The gaseous flow of NO / N2 brought by the injection conduit 502 mixes with the air directly in the inspiratory branch 61A of the ventilation circuit 61 so as to obtain a final therapeutic mixture containing essentially oxygen, nitrogen and the desired proportion of NO.

[0074] The desired proportion of NO depends on the dosage set by the physician, the type of patient (adult, child, infant, etc.), the pathology considered (PPHN, pulmonary hypertension, etc.), or other. In general, the NO content is between 1 and 80 ppmv of NO in the final therapeutic mixture which is supplied to the patient P, via the respiratory interface 63.

[0075] The patient ventilation circuit 61 further comprises an expiratory branch 61B for recovering the CO2-rich gases exhaled by the patient and conveying them to the medical ventilator 1, in particular for analysis purposes, before they are released into the atmosphere.

[0076] The inspiratory 61A and expiratory 61B branches, like flexible pipes, are connected to a connecting piece 62, called a Y-piece, arranged upstream of the respiratory interface 63.

[0077] Optionally, a gas humidifier (not shown) may be arranged on the inspiratory branch 61A to humidify the gas supplied to the patient P.

[0078] Furthermore, a flow sensor 64 is provided arranged on the inspiratory branch 61A, between the fan 60 and the NO injection site supplied by the injection conduit 502. This flow sensor 64 may comprise an upstream line 64A and a downstream line 64B for measuring pressure which are fluidically connected to the flow sensor 64 at connection sites located upstream and downstream of an internal restriction, in order to carry out the pressure measurements of the circulating flow there, before and after pressure loss caused by the internal restriction (not detailed).

[0079] The lines 64A, 64B form pressure measurement conduits which provide the pressure measurements of the circulating flow, before and after pressure loss, to a differential pressure sensor P 55 arranged in the NO delivery device 50. This differential pressure sensor 55 is integrated in the housing 503 of the NO delivery device 50 and is either electrically connected to the control unit 53, or transmits the pressure measurements to it so that they can be processed electronically there.

[0080] The control unit 53 further constitutes a data processing system, in particular measurements made by the sensors or other, making it possible in particular to determine the flow rate of the air circulating in the inspiratory branch 61 A.

[0081] Knowing this flow rate allows the control means 53 to determine the quantity of NO / N2 to be injected into the air flow to obtain the desired NO content in the final therapeutic mixture, i.e. resulting from the injection of the NO / N2 mixture into the air circulating in the lumen of the inspiratory branch 61A. The control means 53 will then cooperate with the control means 55 of the flow rate and / or the pressure of the NO delivery device 50 to regulate the flow of NO / N2 mixture (i.e. flow rate and / or pressure) supplying the injection conduit 502 supplying the NO / N2 mixture.

[0082] Using a gas cartridge 1 according to the invention within such an installation 100 for supplying, i.e. delivering, a gas containing NO to a patient makes it possible to reduce the general size of the installation while facilitating its handling, in particular the replacement of the empty cartridge with a full cartridge 1, and this, at a controlled cost.

[0083] Such an installation can be used to supply NO-based gas mixtures to patients, in particular adults, children, adolescents or newborns, suffering from pulmonary hypertension and / or hypoxia, which can cause pulmonary vasoconstrictions or the like, for example caused by pulmonary pathologies or disorders such as PPHN (persistent pulmonary hypertension of the newborn) or ARDS (acute respiratory distress syndrome), or even caused by a heart surgery operation with the patient being placed on extracorporeal blood circulation.

Claims

Claims

1. Use of a pressurized gas storage cartridge (1) comprising: - a main body (11) comprising an internal volume (12) of less than 1000 mL for containing a NO / N2 gas mixture, and - a distribution valve (2) for controlling the outlet of the NO / N2 gas mixture from the internal volume (12) of the main body (11), in which the NO / N2 gas mixture is stored within the internal volume (12) of the main body (11), said NO / N2 gas mixture having an NO concentration of between 15,000 and 25,000 ppmv, at a pressure of less than 15 bar, measured at 23°C.

2. Use according to claim 1, characterized in that: - the internal volume (12) of the main body (11) of the cartridge (1) is less than or equal to 900 mL, - the NO concentration in the NO / N2 gas mixture is between 20,000 and 24,000 ppmv, and / or - the gas pressure in the internal volume (12) of the main body (11) is less than or equal to 13 bar, measured at 23°C, preferably less than or equal to 12 bar, more preferably less than or equal to 11.5 bar.

3. Use according to claim 1, characterized in that the main body (11) has a bullet shape and / or is made of aluminum alloy.

4. Use according to claim 1, characterized in that the main body (11) of the cartridge (1) is closed at its upper end (10a) by a cover (21), the dispensing valve (2) being carried by the cover (21), preferably a cover (21) made of aluminum alloy.

5. Use according to claim 4, characterized in that: - the cover (21) of the cartridge (1) is shaped to have a central bead (213) comprising a central passage (217) and defining an internal compartment (213A) and - the distribution valve (2) of the cartridge (1) comprises an exhaust channel (22) associated with a seat element (26), said exhaust channel (22) being movable in axial translation within the central passage (217) of the central bead (213), and the seat element (26) cooperating with a sealing element (23) to operate a gas seal and prevent any passage of gas from the internal volume (12) of the cartridge (1) to the exhaust channel (22).

6. Use according to claim 5, characterized in that the seat element (26) is normally pushed towards the sealing element (23) by an elastic means (25), preferably by means of a diffuser element (27) arranged between the seat element (26) and the sealing element (23).

7. Use according to claim 6, characterized in that the seat element (26) is movable in translation in a support part (24) forming a sleeve (241) housing the seat element (26) and the elastic means (25), and preferably the diffuser element (27), said support part (24) being housed and fixed in the internal compartment (213A) of the central bead (213).

8. Use according to claim 5, characterized in that the exhaust channel (22) comprises a free downstream end (222) located outside the central bead (213) and an upstream end (220) located in the internal compartment (213A) of the central bead (213) and cooperating with the seat element (26).

9. Use according to claim 2, characterized in that the internal volume (12) of the main body (11) of the cartridge (1) is less than or equal to 800 mL and / or the NO concentration in the NO / N2 gas mixture is between 22,500 and 23,500 ppmv.

10. Use of a gas cartridge (1) according to one of claims 1 to 9 as a source of NO for supplying with NO / N2 gas mixture the NO delivery device (50) of an installation (100) for supplying gas to a patient (P) comprising: - said at least one source of NO (1), - said NO delivery device (50), an inspiratory branch (61 A) of a patient circuit (61) supplied with NO / N2 gas mixture by the NO delivery device (50), and a medical ventilator (60) in fluid communication with the inspiratory branch (61 A) for supplying said inspiratory branch (61 A) with a respiratory gas containing at least 21% oxygen, preferably air or an oxygen / nitrogen mixture.

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