SYSTEM FOR STORING AND DISTRIBUTING AN NO/NITROGEN GASEOUS MIXTURE

Abstract

The invention relates to a system for storing and distributing a gaseous mixture formed of NO/N.sub.2, comprising a container (6) containing an NO/nitrogen mixture equipped with an in-built pressure regulator (8) with an internal passage (22) for gas made of stainless steel and means for regulating the expansion of the gas collaborating with an expansion valve (27) and a valve seat (28) made of stainless steel. A first outlet coupling (21a) referred to as a ‘pressure’ outlet delivers the gas at low pressure and a second outlet coupling (21b) associated with a flow meter device comprising calibrated orifices and a flow rate selection member delivers the gas at several different flow rates. The invention also relates to an installation for distributing a gas containing NO to a patient comprising a ventilator (1) delivering a gas containing oxygen and to a system for storing and distributing a gaseous mixture formed of NO/N.sub.2 according to the invention.

Claims

1. A system for storing and distributing a gaseous mixture made up of NO/N.sub.2, said system including: a container (6) for conditioning gas which contains a gaseous mixture made up of NO and nitrogen, and a built-in pressure regulating valve (8) including a valve body (D) in metal which includes a gas inlet (20), at least one gas outlet (21; 21a, 21b) and at least one internal gas passage (22) which traverses said valve body (23) in order to connect the gas inlet (20) fluidically to said at least one gas outlet (21; 21a, 21b), said built-in pressure regulating valve (8) being fixed on the conditioning container (6), wherein: at least the part of the valve body (23) traversed by said internal gas passage (22) is in stainless steel, and the built-in pressure regulating valve (8) further includes: a subsystem for regulating the gas expansion which cooperate with a pressure relief valve (27), said valve (27) cooperating with a valve seat (28), the pressure relief valve (27) and the valve seat (28) being in stainless steel, a first pressurized outlet connection (21a) which is configured for and adapted to delivers a low pressure gas between 1 and 10 bar inclusive, and a second flow rate outlet connection (21b) which is associated with a flow meter device which includes calibrated orifices and a flow rate selecting device configured for and adapted to allow the gaseous mixture containing NO/nitrogen to be delivered at several different gas flow rates.

2. The system of claim 1, wherein the valve body (23) is entirely in stainless steel.

3. The system of claim 1, wherein the conditioning container (6) is cylindrical in shape and includes a bottom and a neck with an outlet orifice, the conditioning container (6) being fixed at the level of said outlet orifice, and the built-in pressure regulating valve (8) is protected by a protective cover.

4. The system of claim 1, wherein the valve (8) includes between 2 and 20 calibrated orifices each with different diameters.

5. The system of claim 1, wherein the built-in pressure regulating valve (8) further includes means for controlling the release of the gas.

6. The system of claim 1, wherein the subsystem for regulating the expansion of the gas and/or the flow rate selection device include one or more rotational members (24) which can be actuated manually by a user.

7. The system of claim 1, wherein the calibrated orifices are arranged upstream of the second outlet connection (21b) such that the gas traverses one of said calibrated orifices before reaching the second outlet connection (21b).

8. The system of claim 1, wherein the calibrated orifices have increasing diameters corresponding to different flow rates.

9. The system of claim 1, wherein the conditioning container (6) has an internal volume which is less than or equal to 20 liters (equivalent in water).

10. The system of claim 1, wherein the system further comprises a device configured for and adapted to track the operating life of the cylinder in volume remaining and/or in time remaining.

11. The system of claim 1, wherein the calibrated orifices have increasing diameters corresponding to flow rates of between 50 ml/min and 5 l/min inclusive.

12. The system of claim 1, wherein the calibrated orifices are provided by a rotary disk which is arranged in the gas passage upstream of the second outlet connection (21b).

13. The system of claim 1, wherein the outlet connection for the low pressure gas includes a failsafe device.

14. An installation for distributing a gas containing NO to a patient, said installation including: a ventilator (1) which delivers a gas containing oxygen, a system for storing and distributing a gaseous mixture made up of NO/N2 as claimed in claim 1, a patent circuit (2) which is connected fluidically to the ventilator (1), and a device (5) for distributing NO which is configured for and adapted to control the quantity of NO/N2 originating from the storage and distribution system and released into the patient circuit (2).

15. 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 as claimed in claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The present invention will now be better understood thanks to the description given below with reference to the accompanying figures, in which:

[0065] FIG. 1 is an embodiment of an installation for distributing NO which is supplied by a system for conditioning gas according to the invention and

[0066] FIG. 2 is a general schematic diagram of the operation of a built-in pressure reducing valve (PRV) of a system for storing and distributing gas which complies with the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0067] 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 FIG. 1.

[0068] 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.

[0069] 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.

[0070] The ventilator 1 is supplied, via a connecting line 10, with a gas containing oxygen, for example air (O.sub.2 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.

[0071] The oxygen-rich gas is delivered into the inspiratory branch 3 of the patient circuit 2 by the ventilator 1.

[0072] 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.

[0073] The device 5 for distributing NO is itself supplied with NO/N mixture, via a gas supply line 9, by a NO/N.sub.2 container which is part of a system for storing and distributing according to the invention.

[0074] The NO/N.sub.2 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.

[0075] 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.

[0076] 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 FIG. 2.

[0077] FIG. 2 shows an embodiment of a built-in pressure reducing valve or “PRV” which is produced in stainless steel and is designed to be mounted on a container for conditioning the gaseous mixture of NO and nitrogen, in particular by means of screw-connection on the neck of a gas cylinder.

[0078] 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 FIG. 1.

[0079] According to the invention, the PRV includes two gas outlet connections 21, 21a, 21b which include: [0080] a first so-called “pressurized” gas outlet connection 21a which delivers low pressure gas of typically between 1 and 10 bar inclusive, to which gas delivering apparatuses are connected. The first gas outlet connection 21a is supplied by gas which originates from the high pressure gas source and has been expanded by the expanding means of the PRV, in particular the valve and the valve seat. [0081] and a second given flow rate outlet connection 21b which delivers gas flow rates which are selected corresponding to predetermined volumes so as to supply different gas flow rates, for example between 5 and 20 different flow rates, typically between 10 and 15 different flow rates, which are chosen by the user in terms of the patient in question, for example an adult or child. The second outlet connection therefore allows for gaseous NO to be delivered at different gas flow rates which can be selected by means of several calibrated orifices with increasing diameters. The calibrated orifices with different diameters form part of a flow meter type device or system. In a preferred manner, the calibrated orifices are developed on a rotary disk which is arranged in the gas passage upstream of the second given flow rate outlet connection 21b. The second outlet connection 21b therefore allows gas to be delivered at different flow rate values of between 50 ml/min and 5 l/min inclusive, typically of between 75 ml/min and 2 l/min, in particular of between 100 ml/min and 1.5 l/min.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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 O.sub.2-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.

[0088] 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.

[0089] (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.

[0090] The singular forms “a”, “an” and “the” include plural referents, unless the context clearly dictates otherwise.

[0091] “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.

[0092] “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.

[0093] 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.

[0094] 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.

[0095] 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.