The invention concerns a system for storing and distributing a gaseous mixture made up of NO/N2, said system including a built-in pressure regulating valve or ‘PRV’ in stainless steel which is mounted on a container for conditioning the gaseous mixture of NO and nitrogen to a concentration of at least 200 ppmv (ppm in volume) and being able to go to 3500 ppmv, and at a pressure of between 100 and 500 bar.
Gaseous NO is conventionally utilized at different concentrations of between 200 and 1000 ppm in volume (hereafter referred to as ‘ppmv’), the remainder of the gaseous mixture being nitrogen, in order to treat pulmonary vasoconstrictions, notably pulmonary hypertension in patients undergoing cardiac surgery or in hypoxic newborns. Documents EP-A-786264 and EP-1516639 may be cited to this effect.
The NO/nitrogen gaseous mixture is generally conditioned at a pressure of between 100 and 200 bar absolute in a container, such as a gas cylinder, which is provided with a valve unit allowing the gas output from said container to be controlled.
In view of its very high pressure, the gas must be expanded before it is administered to the patient so as to reduce its pressure and to make it compatible to be administered by inhalation.
A gas pressure regulator which is either fixed on the valve outlet or built into the device for administering and monitoring the NO, situated downstream of the valve and being connected to said valve by means of a high-pressure type hose, is used for this purpose.
Document WO-A-99/49921 teaches an installation of this type with an NO cylinder provided with a gas distributing valve and an external gas pressure regulator which is fixed at the valve outlet.
However, these systems give rise to certain problems.
Thus, when the pressure regulator is connected to the valve by a hose, said hose harbors a risk of injury for the users in view of the high pressure which it conveys since it can be a source of improper handling.
In addition, a significant volume of gas can be contained in a hose containing high pressure gas, which potentially results in NO2 being formed and therefore necessitates regularly purging the hose.
In the case where the pressure regulator is fixed on the outlet connection of the valve, there is the problem of overcrowding as said pressure regulator is an additional element for connection on the valve, which may for example hamper the users.
In addition, there is also a risk connected with the high pressure of the gas when the pressure regulator is installed on the cylinder. It must be possible to use the gaseous mixture containing NO very rapidly. Hence, either the pressure regulator is left on the cylinder, which gives rise to a risk of damage if the cylinder is dropped, or it is installed in retrospect, but, in this case, the installation time will delay the start of the treatment.
EP-A-2541120 also makes known a system for storing and distributing NO/N2 said system including a container for conditioning the NO/nitrogen gaseous mixture, provided with a built-in pressure regulating valve (PRV) which allows the flow rate and the pressure of the outlet gas to be controlled.
Said type of system allows certain of the above-mentioned problems to be resolved but does not solve the one regarding compatibility between the materials making up the PRV and the stored mixtures and, in certain cases, it has been possible in practice to confirm deterioration of the passage carrying the gas and/or of the pressure-reducing elements, in particular of the valve and/or the seat of the valve.
In addition, said type of PRV does not allow the outlet flow rate to be adjusted independently of the pressure and vice versa. Similar or analogous devices are taught by documents WO-A-41856, EP-A1515080 and DE-A-19744047.
The problem to be solved, therefore, is to be able to realize a reduction in the pressure of the gaseous mixture containing NO without coming across any or part of the abovementioned problems.
The solution is a system for storing and distributing a gaseous mixture made up of NO/N2, said system including:
Thanks to the present invention, the users are no longer exposed to gaseous high pressure as the gas is expanded directly in the built-in pressure regulating valve and is therefore output at low pressure, that is to say typically between 1 and 10 bar absolute 2, for example between 2 and 7 bar absolute.
The low pressure can be fixed at a desired level thus allowing the system for delivering NO supplied by expanded gas to function well.
In addition, this also avoids the risks of improper handling which exist with the former valves and the low pressure outlet of the pressure reducing valve is able to be connected directly to a system for administering and monitoring NO.
In addition, the solution of the invention also allows a reduction in the overall space required to be obtained as it is no longer necessary to add an additional pressure reducer to the valve outlet.
Finally, the solution of the invention also allows NO to be delivered at different flow rates so as to be able to be adapted to a specific situation, like ventilation with a ventilator for administering gas or, in contrast, without a ventilator, for example in an emergency.
According to the case, the system of the invention can include one or several of the following technical characteristics:
The invention also concerns an installation for distributing a gas containing NO to a patient, said installation including:
Furthermore, the invention also concerns a method for distributing a mixture containing NO/N2, which method uses a system for storing and distributing a gaseous mixture made up of NO/N2 according to the invention or an installation for distributing a gas containing NO to a patient according to the invention.
The present invention will now be better understood thanks to the description given below with reference to the accompanying figures, in which:
The storing and distributing system according to the invention can be used in order to supply an installation for distributing NO to patients suffering from pulmonary vasoconstrictions, for example via the NO distributing installation, an embodiment of which is shown in
Said installation includes a ventilator 1 with a respiratory circuit or patient circuit 2 with two branches, that is to say one inspiratory branch 3 and one expiratory branch 4. The inspiratory branch 3 is designed to route the respiratory gas from the ventilator to the patient P, whilst the expiratory branch 4 is designed to route the gas exhaled by the patient P to the ventilator 1.
In terms of the patient P, the administering of the gas is effected by means of a patient interface 11, for example a respiratory mask, a tracheal cannula or nasal cannula.
The ventilator 1 is supplied, via a connecting line 10, with a gas containing oxygen, for example air (O2 content 21% by volume) or the oxygen is delivered from an oxygen source 7, such as an oxygen cylinder or a pipe carrying oxygen originating from an oxygen producing unit, such as a modulated pressure unit (PSA), or an oxygen storage unit, such as a buffer tank or storage tank.
The oxygen-rich gas is delivered into the inspiratory branch 3 of the patient circuit 2 by the ventilator 1.
Moreover, a device 5 for distributing NO is connected fluidically to said inspiratory branch 3 of the patient circuit 2 in order to deliver there, via a supply line 12, an NO/N mixture, for example 200, 400, 800 or 1500 ppmv NO and the remainder being nitrogen.
The device 5 for distributing NO is itself supplied with NO/N mixture, via a gas supply line 9, by a NO/N2 container which is part of a system for storing and distributing according to the invention.
The NO/N2 container 6 is a gas cylinder, for example produced in composite fibers, in aluminum or in an aluminum alloy containing 0.5, 2, 5, 10, 11 or 20 liters (equivalent in water), provided with a built-in pressure reducing valve 8, in a preferred manner protected against impacts by means of a protective cover.
The built-in pressure reducing valve 8, called a “PRV”, allows the outlet of the gas from the container 6 and its outlet pressure to be controlled, notably by means of a pressure relief valve 27 and a valve seat 28.
Said PRV 8 is made up by a body which is traversed by one or several gas passages 22 which connect a gas inlet 20, which is situated at the fixing end of the PRV on the neck of the cylinder, to one or several outlet connections 21 through which the gas leaves the PRV again, after expansion, as detailed below with reference to
Said PRV 8 includes a valve body 23 (seen in section) which includes an internal gas passage 22 which connects, on the one hand, a gas inlet 20, by means of which the NO/nitrogen mixture is extracted from the body of the gas cylinder 6, on which said PRV 8 is mounted, and, on the other hand, several gas outlets 21, that is to say gas outlet connections, by means of which the NO/nitrogen mixture leaves the PRV 8, before being conveyed to the patient P, as explained above with reference to
According to the invention, the PRV includes two gas outlet connections 21, 21a, 21b which include:
One or several control members 24, such as a rotary member which is able to be handled by an operator, allow the release of the gas to be controlled and the desired flow rate to be selected. This is therefore a gaseous flow rate selector, for example a knob or a rotary wheel.
In particular, a flow rate control member 24 acts on the rotary disk so as to be able to ensure that a selection of the desired flow rate value is delivered by the second outlet connection 21b.
So as to minimize the corrosion of the elements of the PRV 8 in view of the corrosive nature of the NO/nitrogen gaseous mixture, the body 23 of the PRV 8 is realized entirely or in part, but preferentially entirely, in stainless steel.
Indeed, stainless steel is used as the material constituting the passages and other elements in contact with the gas containing NO. Thus, the gas passage or passages are in particular drilled through stainless steel parts of the body 3 of the PRV 8. In the same way, the pressure relief valve 27 and/or the valve seat 28, and/or other elements are also produced in stainless steel.
The PRV 8 further comprises a manometer 25 and a filling connection 26 which allows the cylinder 6 to be filled with gas when it is empty, that is to say when all the gas has been consumed. The PRV 8 comprises or can comprise, moreover, other classic components, such as springs, gaskets, etc.
Furthermore, the device 5 for distributing NO notably allows the quantity of NO/N released into the inspiratory branch 3 to be controlled, as well as the mode of releasing said mixture, that is to say in a continuous manner or in a pulsed manner, for example solely during the inspiratory phases of the patient P. The NO/N mixture is therefore diluted in the inspiratory branch 3 with the O2-rich mixture distributed by the ventilator 1. The diluting is a function of the content of the initial NO/N mixture but also of the gas concentration to be administered to the patient.
It will be understood that many additional changes in the details, materials, steps and arrangement of parts, which have been herein described in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. Thus, the present invention is not intended to be limited to the specific embodiments in the examples given above.
(For Allen) While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the appended claims. The present invention may suitably comprise, consist or consist essentially of the elements disclosed and may be practiced in the absence of an element not disclosed. Furthermore, if there is language referring to order, such as first and second, it should be understood in an exemplary sense and not in a limiting sense. For example, it can be recognized by those skilled in the art that certain steps can be combined into a single step.
The singular forms “a”, “an” and “the” include plural referents, unless the context clearly dictates otherwise.
“Comprising” in a claim is an open transitional term which means the subsequently identified claim elements are a nonexclusive listing (i.e., anything else may be additionally included and remain within the scope of “comprising”). “Comprising” as used herein may be replaced by the more limited transitional terms “consisting essentially of” and “consisting of” unless otherwise indicated herein.
“Providing” in a claim is defined to mean furnishing, supplying, making available, or preparing something. The step may be performed by any actor in the absence of express language in the claim to the contrary.
Optional or optionally means that the subsequently described event or circumstances may or may not occur. The description includes instances where the event or circumstance occurs and instances where it does not occur.
Ranges may be expressed herein as from about one particular value, and/or to about another particular value. When such a range is expressed, it is to be understood that another embodiment is from the one particular value and/or to the other particular value, along with all combinations within said range.
All references identified herein are each hereby incorporated by reference into this application in their entireties, as well as for the specific information for which each is cited.
Number | Date | Country | Kind |
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1362490 | Dec 2013 | FR | national |
This application is a 371 of International PCT Application PCT/FR2014/053084 filed Nov. 28, 2014 which claims priority to French Patent Application No. 1362490 filed Dec. 12, 2013, the entire contents of which are incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/FR2014/053084 | 11/28/2014 | WO | 00 |