NO delivery device with manual ventilation system

Abstract

Title of the invention: NO delivery apparatus with manual ventilation system. The invention relates to an NO delivery apparatus (1) comprising a main gas circuit with a main outlet, and a backup circuit (20) comprising a backup NO circuit (21) comprising a backup NO line (24), and a backup O2 circuit (22) comprising a main O2 line (31) fluidically connected to form a common backup line (61) in fluidic communication with a backup outlet (62). The oxygen flow rate is set between 0 and 20 L / min. The NO flow rate is adjusted to obtain a mixture containing oxygen and NO between 0 and 80 ppmv. Abstract figure: Fig. 2

Description

Title of the invention: NO delivery device with manual ventilation system

[0001] The present invention relates to a device for supplying gaseous nitric oxide (NO) equipped with a backup system to ensure delivery of NO, in normal mode, in backup mode in case of failure or in manual ventilation mode by bag-valve-mask (BVM), and a patient NO administration installation comprising such a NO supply device.

[0002] Inhaled nitric oxide or NOi is a gaseous drug commonly administered by means of an NO delivery system to treat persons, i.e. patients, suffering from acute pulmonary arterial hypertension, in particular pulmonary vasoconstrictions in adults or children, including newborns (PPHN), as described for example by EP-A-560928 or EP-A-1516639.

[0003] A NO delivery system typically comprises an NO delivery device providing an NO / N2 mixture and a medical ventilator providing an N2 / O2 mixture with at least 20% vol. of oxygen, such as air, supplying a patient circuit to deliver a combined NO / N2 / O2 gas mixture to the patient being treated. Examples of such NO delivery systems are given in documents WO-A-2012 / 094008, US-A-2015 / 320951, US-A-2015 / 273175, JP-A-H11192303, WO-A-02 / 40914, and US-A-2003 / 116159.

[0004] In the event of the need to ventilate the patient with a manual ventilation bag (BVM), at the request of the nursing staff, the NO supply device must be able to continue to supply the NO / N2 mixture so that the patient's treatment is not abruptly interrupted, for obvious safety reasons, given that an abrupt interruption of NOi treatment could be fatal to fragile patients, in particular newborns suffering from PPHN.

[0005] To ensure NO delivery, for example in the case of ventilation by a manual bag-valve-mask (BVM), it is known to equip the NO delivery device with a secondary system or circuit, called a backup circuit, designed to deliver an adjustable flow rate of O2 and a fixed flow rate of NO, which are mixed together in the NO delivery device before being injected into the BVM via a dedicated outlet, i.e., a BVM outlet fitting. Oxygen is typically supplied by an oxygen source, such as a pressurized oxygen cylinder, connected to the NO delivery device, as described by EP-A-3233171.

[0006] However, such a solution is not ideal because the NO concentration of the resulting gas mixture (i.e., NO / N2 + O2) varies according to the set oxygen flow rate since the NO flow rate is fixed, which is not desirable from a therapeutic point of view because it must be possible to deliver a given dosage to the patient, including in manual ventilation mode via a manual insufflator, i.e. a manual ventilation bag (BVM).

[0007] In view of this, one problem is to propose an improved NO delivery device, which is capable of supplying a NO / N2 / O2 gas mixture, in case of switching to manual ventilation by manual insufflator or BVM, and an NO administration installation including such an NO delivery device.

[0008] One solution of the invention relates to an apparatus or device for delivering or supplying NO (i.e. nitrogen monoxide) comprising a main gas circuit including at least one main NO line fluidly connecting at least one NO inlet port to a main outlet port; and a backup circuit including a backup NO circuit including a backup NO line and a backup O2 circuit including a main O2 line.

[0009] Furthermore:

[0010] - a downstream portion of the emergency NW line connects fluidly to a junction site, at a downstream portion of the main O2 line to form a common emergency line in fluidic communication with an emergency exit,

[0011] - the downstream portion of the main O2 line of the backup circuit includes O2 flow control means allowing the oxygen flow rate to be set between 0 and 20 L / min, and

[0012] - the downstream portion of the emergency NW line of the emergency circuit includes means of adjusting the NO flow rate (therefore the NO concentration) allowing adjustment of the NO flow rate supplied to the downstream portion of the emergency NO line to obtain, within the common emergency line, a combined gas mixture containing oxygen and NO in a proportion between 0 and 80 ppmv.

[0013] Furthermore, the oxygen flow control means include a second variable orifice device associated with an O2 control device.

[0014] In addition, the means for adjusting the NO flow rate include a first variable orifice device associated with an NO adjustment device.

[0015] It finally includes a fixed orifice device arranged in the downstream part of the main O2 line, upstream of the junction site.

[0016] According to another aspect, the invention also relates to an installation for supplying a gas containing NO, that is to say, for administering a therapeutic gas containing NO, to a patient (P) comprising an NO delivery device according to the invention, in particular as described above, supplied with a NO / N2 mixture by at least one pressurized gas and oxygen container by a pressurized oxygen container, said NO supply device providing: - either a NO / N2 mixture via the main outlet, to a breathing gas circuit connected to a medical ventilator, - either a NO / N2 / O2 mixture via the secondary, i.e. emergency, port to a manual resuscitator or BVM.

[0017] Depending on the embodiment considered, the therapeutic gas administration installation of the invention may include one or more of the following features: - said at least one pressurized gas container contains the N0 / N2 mixture. - said at least one pressurized gas container contains a mixture of NO / N2 containing 100 to 2000 ppmv of NO, the remainder being nitrogen, preferably 100 to 1000 ppmv of NO (remaining nitrogen). - the pressurized oxygen container(s) contains medical oxygen. - the gas container(s) contain a NO / N2 mixture or oxygen medical at a pressure of at least 150 bar, or even at least 180 bar. - the containers are gas cylinders.

[0018] The invention will now be better understood with reference to the following detailed description, given by way of illustration but not limitation, with reference to the accompanying figures, among which:

[0019] [Fig-1] represents an embodiment of a gas administration installation therapeutic to a patient P incorporating a NO delivery device, as described by EP-A-4241817.

[0020] [Fig.2] schematically illustrates an embodiment of the backup circuit of a device supply of NO according to the invention.

[0021] [Fig.1] schematically illustrates an embodiment of a therapeutic gas delivery system 100, i.e. a gas mixture based on NO, to a patient P incorporating a NO supply device 1, as described by EP-A-4241817.

[0022] It comprises two gaseous NO containers 5, each containing a gaseous mixture of NO and nitrogen (N2), i.e., an NO / N2 mixture, containing less than 2000 ppmv of NO, typically from 250 to 1000 ppmv of NO, and nitrogen (N2) for the remainder, conditioned to a pressure of up to 180 bar or more, for example, an NO / N2 mixture containing 450 ppmv or 800 ppmv of NO. Such gas containers 5 are commonly referred to as "NO cylinders".

[0023] The NO 5 bottles supply the NO / N2 mixture to a NO 1 delivery device, such as that according to the invention, the internal architecture of which is illustrated in [Fig.2] and explained below.

[0024] The NO 1 supply device is also fluidly connected, via an oxygen supply line, such as a flexible hose, to a pressurized oxygen container 9, such as an O2 cylinder or, alternatively, to a hospital oxygen supply network.

[0025] Furthermore, the installation 100 also includes a medical ventilator 2, that is, a respiratory support device, providing a flow of respiratory gas containing at least 20% vol. oxygen, such as air or an oxygen / nitrogen (N2 / O2) mixture. The medical ventilator 2 is fluidically connected to the patient P via a respiratory gas circuit 3 comprising an inspiratory branch 30 for supplying the respiratory gas and an expiratory branch 31 for recovering the exhaled CO2-enriched gas. The two branches 30 and 31 are in fluidic communication with a respiratory interface 4, such as a tracheal tube, a mask, or other device, via a Y-connector.

[0026] As can be seen, the NO supply device 1 allows the NO / N2 mixture to be injected into the inspiratory limb 30, via an NO injection conduit 11 (in 8), so as to produce a mixture of the NO / N2 flow and the respiratory gas flow containing at least 20% O2, i.e. air or oxygen / nitrogen mixture, delivered by the medical ventilator 2, and obtain a combined gas which contains oxygen (>20% vol. approx.), nitrogen and a variable and adjustable concentration of NO, typically between 1 and 80 ppmv, due to the dilution produced during the mixing of the gas flows.

[0027] A gas humidifier 6 is arranged on the inspiratory branch 30 downstream of the injection site 8 serving to humidify the gas flow.

[0028] The inspiratory branch 30 also conventionally includes, upstream of the injection site 8, a flow sensor 7, for example of the mass type or differential pressure type, connected to the NO supply device 1, in particular to the control means of the NO supply device 1, in order to determine the gas flow rate from the ventilator 2 and to regulate the NO flow rate, in particular to be able to choose the flow rate of NO / N2 mixture to be injected according to the desired NO content, the composition of the NO / N2 mixture from the cylinders and the gas flow rate (i.e. air or air / O2) from the ventilator 2. A gas sampling line 10 is used to collect gas samples and to check their conformity with the desired gas mixture to be administered to patient P.

[0029] The NO 1 supply or delivery device includes an internal main gas circuit for conveying the NO / N2 mixture, equipped with NO / N2 flow control means, such as valves, calibrated orifices..., controlled by the control means of the NO supply device 1, typically a (or more) microprocessor arranged on an electronic board.

[0030] In addition, the NO supply device 1 includes a backup circuit 20 or secondary circuit, called the "backup" circuit, designed to deliver an adjustable O2 flow rate and a fixed NO flow rate in order to ensure a supply of NO, in particular when the user wishes to supply NO to a patient using a BVM connected to a dedicated secondary outlet 62, as illustrated in [Fig.2].

[0031] The main gas circuit of the NO supply device 1, which carries the NO / N2 mixture during normal operation of the device 1, is not shown because it is identical to that described by EP-A-4241817, to which reference will be made for further details.

[0032] Thus, as taught by EP-A-4241817, the emergency circuit 20 consists of an emergency NO circuit 21 and an emergency O2 circuit 22, each of which includes gas pipes, passages or conduits for conveying gases or gas mixtures.

[0033] The NO 21 emergency circuit is supplied with NO / N2 by two NO 23 inlet sections arranged in parallel, themselves supplied by the NO 5 cylinders. They join together to form a common emergency NO line 24 intended to carry the NO / N2 mixture.

[0034] The backup NO line 24 further includes a first pressure regulator 25 for reducing or controlling the pressure of the NO / N2 mixture, for example to deliver a reduced pressure equal to approximately 3.2 bar relative, and a pneumatic valve 26, located downstream, for controlling the circulation of the NO / N2 mixture. The opening of the pneumatic valve 26, and therefore the passage of the NO / N2 flow, is controlled by the pressure of the oxygen flow supplied by the main O2 line 22.

[0035] Furthermore, the emergency oxygen circuit 22 includes a main O2 line 31 connected to the O2 cylinder 9, which brings gaseous oxygen to a pressure typically between 3 and 6 bar.

[0036] The downstream portion 31a of the main O2 line 31 connects at a junction site 60 to the downstream portion 24a of the emergency NO line 24, downstream of the O2 flow indicator devices 36 and NO 28, so as to operate a mixing of the oxygen flow and the NO / N2 flow which can supply the common line 61 which carries the gas to the secondary outlet orifice 62, i.e. where the BAVU is connected, as seen in [Fig.2].

[0037] The main O2 line 31 includes a first control valve 32 and a second pneumatic control valve 33. The first control valve 32, typically of the on / off type, controls the flow of oxygen in the main O2 line 31. It is operated by an actuation means 40, such as a rotary selector, push button, selection key or similar, operable by the user when he wishes to activate the backup circuit 20 and allow the passage of oxygen.

[0038] A first section of conduit 31.1 connects fluidly to the main O2 line 31 in order to pneumatically control the second pneumatic control valve 33, as described by EP-A-4241817.

[0039] Furthermore, the activation of an actuation means 40 by the user leads to a quasi-synchronized and / or quasi-simultaneous release of the NO / N2 and O2 mixture flows within the emergency NO circuit 21 and the emergency oxygen circuit 22, thus leading to their mixing from and downstream of the junction site 60, i.e. in the common emergency line 61 which leads to an emergency outlet 62, i.e. a secondary outlet, for example carried by a connecting connector or similar, to which a manual gas blower, i.e. a manual ventilation bag or similar, can be connected.

[0040] Generally speaking, reference will be made to EP-A-4241817 for more details on the installation 1, on the NO 1 supply or delivery device and on the internal architecture and operation, as they are broadly identical to those described in the context of the present invention, with the exception of the differences mentioned below.

[0041] A problem which arises in view of EP-A-4241817 is that the concentration of NO in the NO / N2 / O2 mixture varies according to the oxygen flow rate set by the user because the NO flow rate is fixed.

[0042] Thus for a bottle 5 supplying NO at a concentration of 800 ppmv, the concentration of NO varies between 8 and 32 ppmv for an O2 flow rate between 5 and 20 L / min, whereas for a concentration of 450 ppmv, the concentration of NO varies between 4.5 and 18 ppmv for the same O2 flow rate between 5 and 20 L / min.

[0043] In order to resolve it, according to the invention: - the downstream portion 31a of the main O2 line 31 of the backup circuit 20 includes O2 flow control means 35, 42 allowing the oxygen flow rate to be set between 0 and 20 L / min, and - the downstream portion 24a of the emergency NO line 24 of the emergency circuit 20 includes means for adjusting the NO flow 27, 41 allowing adjustment of the NO flow supplied to the downstream portion 24a of the emergency NO line 24 to obtain, within the common emergency line 61, a combined gas mixture containing oxygen and NO in a proportion between 0 and 80 ppmv.

[0044] More specifically, downstream of the pneumatic valve 25, the backup NO line 24 includes means for adjusting the NO flow rate 27, 41, namely a first variable orifice device 27 (i.e., adjustable orifice) associated with an NO adjustment device 41, allowing the user to select a gas flow rate, i.e., NO / N2. An NO flow rate indicator device 28, located downstream of the first variable orifice device 27, makes it possible to verify that the NO / N2 mixture flow rate is indeed equal to the desired value, for example, on the order of 230 mL / min.

[0045] Similarly, the oxygen flow supplied by the main O2 line 31 first passes through a second pressure regulator 34 used to reduce or control its pressure, for example to obtain a pressure of 1.6 bar, then passes through oxygen flow control means 35, 42, namely a second variable orifice device 35 (i.e. adjustable orifice) associated with an O2 control device 42.

[0046] Here again, an O2 flow indicator device 36, located downstream of the second variable orifice device 35, makes it possible to check that the O2 flow rate is indeed equal to the desired value, for example between 5 and 20 L / min.

[0047] The first and second variable orifices 27, 35 comprise, for example, a rotating disc with calibrated orifices or the like. The NO adjustment device 41 and the O2 adjustment device 42 may comprise or be of the rotary knob, selector button, or similar type. Furthermore, the O2 flow indicator device 36 and the NO2 flow indicator device 28 may be of the ball rotameter or similar type.

[0048] Furthermore, a fixed-orifice device 43, i.e., non-modifiable, is arranged in the downstream portion 31a of the main O2 line 31, upstream of the junction site 60, i.e., the connection point. It creates a pressure drop, the pressure of which is used to control the first pressure regulator 25 to reduce or control the pressure of the NO / N2 mixture. Varying the NO pressure using the first pressure regulator 25 allows the NO flow rate to be varied according to the variation in the oxygen flow rate. The restriction 43 creates a pressure drop that varies according to the O2 flow rate.

[0049] The first pressure regulator 25 makes it possible to generate a NO pressure proportional to the control pressure with a factor > 1. Thus, if a pressure of 100 mbar is applied for example via line 45, a pressure of 2 bar is obtained in line 24, i.e. a multiplication factor of 20.

[0050] Therefore, when the oxygen flow rate increases in the downstream part 31a of the main O2 line 31, the control pressure of the first pressure regulator 25 increases by varying the NO pressure at the outlet of the first regulator. pressure 25 and by inducing an increase in the NO flow rate so as to guarantee a constant concentration independent of the oxygen flow rate.

[0051] The first variable orifice device 27 allows the concentration

[0052] of NO to be varied by varying the flow rate of NO which is mixed with oxygen.

[0053] Generally speaking, the installation 100 for administering therapeutic gas based on NO (< 100 ppmv), O2 (>20% vol) and nitrogen to a patient P, such as the installation 100 of [Fig.1], implemented to treat one or more patients suffering from a pathology or medical condition causing acute pulmonary arterial hypertension, in particular pulmonary vasoconstrictions in adults or children, including newborns, for example to treat PPHN in a newborn, or pulmonary hypertension in a person undergoing cardiac surgery.

Claims

Demands

1. NO delivery apparatus (1) comprising: - a main gas circuit comprising at least one main NO line fluidly connecting at least one NO inlet port to a main outlet port, - a backup circuit (20) comprising a backup NO circuit (21) comprising a backup NO line (24), and a backup O2 circuit (22) comprising a main O2 line (31), and wherein a downstream portion (24a) of the backup NO line (24) fluidly connects at a junction site (60) to a downstream portion (31a) of the main O2 line (31) to form a common backup line (61) in fluidic communication with a backup outlet (62), characterized in that: - the downstream portion (31a) of the main O2 line (31) of the backup circuit (20) comprises O2 flow control means (35, 42) for regulating a oxygen flow rate between 0 and 20 L / min,and - the downstream portion (24a) of the emergency NO line (24) of the emergency circuit (20) includes means for adjusting the NO flow rate (27, 41) allowing the NO flow rate supplied to the downstream portion (24a) of the emergency NO line (24) to be adjusted in order to obtain, within the common emergency line (61), a combined gas mixture containing oxygen and NO in a proportion between 0 and 80 ppmv.

2. Apparatus according to claim 1, characterized in that the oxygen flow control means (35, 42) comprise a second variable orifice device (35) associated with an O2 control device (42).

3. Apparatus according to claim 1, characterized in that the means for adjusting the NO flow rate (27, 41) comprise a first variable orifice device (27) associated with an NO adjustment device (41).

4. Apparatus according to claim 1, characterized in that it further comprises a fixed orifice device (43) arranged in the downstream part (31a) of the main O2 line (31), upstream of the junction site (60).

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