JPH10179742A - Portable nitrogen monoxide-gaseous oxygen supply device and its operation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a movable patient which can make spontaneous respiration to receive a nitrogen monoxide inhalation treatment method at home while having a comfortable daily life by controlling the supply rates of nitrogen monoxide and oxygen by a microcomputer in such a manner that the supply rates are equaled to preset gas supply rates. SOLUTION: A lightweight nitrogen monoxide cylinder 1 supplies the nitrogen monoxide to a nasal fossa cannula 3 via a nitrogen monoxide flow passages 10 and a control valve 5. A lightweight oxygen cylinder 2 supplies the oxygen to this nasal fossa cannula 3 via an oxygen flow passages 11 and a control valve 6. A pressure sensor 7 senses the negative pressure (or positive pressure) and pressure change generated in the nasal fossa by the inhalation (or expiration) of the patient's spontaneous respiration and transmits sensing signals to the microcomputer 8. The microcomputer 8 controls the timing to open and close the control valves 5, 6 (to tune the valves with the spontaneous respiration) in accordance with the preset conditions and the signals from the pressure sensor 7, thereby regulating the flow rates of the nitrogen monoxide and the oxygen to the desired rates.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable nitric oxide-oxygen gas supply device for supplying nitric oxide and oxygen to a home patient who can breathe spontaneously or a mobile patient who is mild, and a method of operating the same.

[0002]

BACKGROUND OF THE INVENTION Conventional nitric oxide inhalation therapy mainly targets acute diseases that can be treated by short-term administration within one week, but as the effects of nitric oxide inhalation therapy are confirmed. There is an increasing demand for use in the treatment of chronic respiratory diseases that allow spontaneous breathing. For example, among patients with chronic respiratory failure who are undergoing home oxygen therapy, many patients also have pulmonary hypertension. Home oxygen therapy has the effect of improving pulmonary hypertension by increasing arterial oxygen concentration in patients with chronic respiratory failure, and the presence or absence of improvement in pulmonary hypertension greatly affects the prognosis of treatment for chronic respiratory failure. Such a patient can be expected to be effectively treated by improving pulmonary hypertension by using the nitric oxide inhalation therapy together.
Furthermore, it can be expected that the supply oxygen concentration is lowered by inhaling nitric oxide to avoid lung injury due to active oxygen. Conventionally, the nitric oxide inhalation method uses an inhalation circuit via a ventilator designed for a short-term administration patient who needs endotracheal intubation, and uses a closed mask instead of the endotracheal tube.

[0003]

However, in the case of inhaled nitric oxide therapy using a ventilator, a device for removing harmful nitrogen dioxide generated by oxidation of nitric oxide is connected to a respiratory circuit. Patients who are able to move, even with the pain of having to lie on the bed for a long time and wear a tight breathing mask, have had to remove the mask every meal. In view of the above problems, the present invention provides a portable nitric oxide-oxygen gas supply device, in which a movable patient capable of spontaneous breathing can receive nitric oxide inhalation therapy at home while living a comfortable daily life. It is intended to provide an operation method thereof.

[0004]

SUMMARY OF THE INVENTION The present invention comprises a nasal cannula 3, a lightweight nitric oxide cylinder 1 for supplying nitric oxide to the nasal cannula via a nitric oxide channel 10 and a control valve 5, and an oxygen flow. A light oxygen cylinder 2 for supplying oxygen to the nasal cannula via the tract 11 and the control valve 6, a sensor 7 for detecting spontaneous breathing of a patient having the nasal cannula attached thereto, and a preset condition and a signal from the sensor A portable nitric oxide-oxygen gas supply device, comprising means 8 for controlling the opening and closing of a control valve, and which can be carried and used by a patient.

In the portable nitrogen monoxide-oxygen gas supply device described above, if a capacitance type differential pressure gauge is used as the sensor 7, it is suitable for detecting spontaneous breathing. Also, by combining the nitric oxide channel 10 and the oxygen channel 11 into one channel immediately before the nasal cannula 3, the generation of nitrogen dioxide can be minimized. For the same reason, it is also preferable to use a plurality of nasal cannulas that can be worn simultaneously depending on the situation, and to connect the nitric oxide channel 10 and the oxygen channel 11 to separate nasal cannulas, respectively.

The present invention also relates to a method for operating the above portable nitrogen monoxide-oxygen gas supply device, characterized in that nitrogen monoxide diluted with nitrogen is used as nitrogen monoxide. A method for operating a nitrogen oxide-oxygen gas supply device is provided. The control valve 5 and / or the control valve 6 is opened by a spontaneous breathing detection signal from the sensor 7, the control valve opened after a predetermined time is closed, and nitric oxide and / or oxygen is pulsed within the inspiratory time of spontaneous breathing. When the control valves 5 and 6 are controlled to supply air, the amount of gas used can be minimized.

Further, in the method of operating the portable nitric oxide-oxygen gas supply device, the control valve 5 and / or the control valve 6 are opened by a spontaneous respiration detection signal from the sensor 7, and the nitric oxide is supplied. And the flow rate of oxygen is controlled so as to be a preset flow rate, and the opening and closing of the control valve 5 and / or the control valve 6 is synchronized with spontaneous breathing, so that nitric oxide and / or oxygen is inspired by spontaneous breathing. The operation method in which the gas is supplied in a pulsed manner within a time can minimize waste of the supply gas and supply a necessary and sufficient gas amount to the patient.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The portable nitrogen monoxide-oxygen gas supply apparatus of the present invention and its operation method will be described in more detail with reference to the drawings. FIG. 1 shows an embodiment of a portable nitric oxide-oxygen gas supply apparatus according to the present invention, in which a nasal cannula 3 and a lightweight nitric oxide cylinder 1 are provided.
A device which can be carried and used by a patient, comprising a lightweight oxygen cylinder 2, a pressure sensor 7 for sensing spontaneous breathing of the patient, and a microcomputer as control means 8 for opening and closing the control valves 5 and 6. It is. In the present embodiment, the control valves 5, 6, the pressure sensor 7 and the microcomputer 8 are composed of a nitric oxide channel 10 and an oxygen channel 1.
It is incorporated in a respiratory-tuned gas supply controller 4 attached to 1.

The lightweight nitric oxide cylinder 1 supplies nitric oxide to the nasal cannula 3 via the nitric oxide channel 10 and the control valve 5. The lightweight oxygen cylinder 2 supplies oxygen to the nasal cannula 3 via the oxygen flow path 11 and the control valve 6. Nitric oxide cylinders and oxygen cylinders are preferred to be bulky and lightweight for home therapy and portable use. Usually, in consideration of the duration of gas and safety, a cylinder having a capacity of about 2 to 3 kg and a capacity of about 3 to 4 liters is used. Further, it is preferable that a pressure regulating valve and a flow regulator are attached to each cylinder so that the gas supply amount can be easily adjusted.

The pressure sensor 7 detects a negative pressure (or a positive pressure) or a change in pressure generated in the nasal cavity due to inspiration (or expiration) of a patient's spontaneous breathing, and transmits a sensing signal to the microcomputer 8. Above all, the capacitance type differential pressure gauge
It is preferably used because it excels in sensing negative pressure (or positive pressure) generated in the nasal cavity by inhalation (or expiration).
However, as long as it can sense the respiratory cycle of the patient, it can be used without being limited to the pressure sensor. FIG.
In, the pressure sensor is attached to the nitric oxide channel 10, but may be attached to the oxygen channel 11 or the nasal cannula 3 if the patient's spontaneous breathing can be easily detected.

The microcomputer 8 controls the timing of opening and closing the control valves 5 and 6 based on a preset condition and a signal from the pressure sensor 7 to adjust the flow rate of gas to a desired amount. That is, the microcomputer 8 opens the control valves 5 and 6 according to the signal from the pressure sensor 7 to flow nitric oxide and oxygen through the respective flow paths. After a lapse of a predetermined very short time, the control valves 5 and 6 are closed to stop the gas supply. Similarly, the supply and stop of the gas are repeated, and the gas is supplied in a pulsed manner at every intake time. Alternatively, the microcomputer may send the control valve opening time required for flowing a gas amount corresponding to a preset prescription flow rate during the inhalation time to the control valves 5 and 6 as a signal duration. . Also in this case, it is preferable to synchronize the opening and closing of the control valves with spontaneous breathing so that the control valves 5 and 6 are opened in a pulsed manner only during the inspiration time and closed during the expiration time. Further, for example, the average value of the time interval between expiration and inspiration over several cycles is obtained by a pressure sensor and a microcomputer, and the start and stop of gas supply can be automatically controlled. If the gas supply timing is set in the first half or the middle of the intake cycle, the gas intake efficiency is generally good. FIG. 2 shows an example of a gas supply pattern. Naturally, air is also sucked in along with the gas.

In any case, the supply amounts of nitric oxide and oxygen are represented by a preset gas supply amount (usually expressed as a flow rate assuming that nitric oxide or oxygen is supplied continuously). It is controlled by the microcomputer 8 so as to be equal. In order to set the gas supply amount in advance, for example, it is convenient to provide a supply flow rate setting scale 9 in the respiratory synchronization gas supply controller 4 incorporating the microcomputer 8. Nitric oxide and oxygen are, for example,
It may be supplied every inspiration time of each respiratory cycle, or nitric oxide and oxygen may be supplied alternately every inspiration time, and can be freely selected and set by microcomputer control. FIG. 2 is an example of the former supply pattern.

In the portable nitrogen monoxide-oxygen gas supply apparatus of the present invention, the nitric oxide channel 10 and the oxygen channel 11 may be combined into one cannula, or a plurality of cannulas may be used. , Each connected to a separate nasal cannula and simultaneously attached to the patient. In the former case, in order to prevent the generation of nitrogen dioxide, the nitric oxide channel 10 and the oxygen channel 11 must be merged into one channel as short as possible to the nasal cannula 3. The nasal cannula need only be a disposable, commonly used in clinical practice.

The nitric oxide source used in the portable nitric oxide-oxygen gas supply apparatus of the present invention may be a pure nitric oxide gas.
In addition, nitrogen monoxide pure gas is converted into an inert gas containing no oxygen,
For example, an appropriate concentration such as nitrogen or helium, for example, 100
It may be used after being diluted to 0 ppm. As the oxygen source, high-purity oxygen generally used in home oxygen therapy or oxygen separated and concentrated from air by a polymer membrane, an adsorbent, or the like can be used.

[0015]

EXAMPLES Next, the present invention will be described based on test examples and comparative test examples.
This will be described more specifically. First, Test Examples 1 to 4 and the ratio
The portable nitric oxide-oxygen gas supply used in Comparative Test Examples 1 and 3
Supply device (hereinafter simply referred to as a portable gas supply device)
The condition was adjusted to Nitric oxide (hereinafter simply referred to as NO)
As a source, an NO mixed gas obtained by diluting NO with nitrogen
Pressure of 120 in a 3.4 liter high pressure vessel made of minium
Kg / cm ^TwoFilled with 1.4Kg / cm^Two Pressure
Flow through the NO flow path at a flow rate of 0.5 to 2 liters / min.
Adjust the pressure regulating valve and flow regulator attached to the container so that
It was adjusted.

As an oxygen source, medical oxygen gas (oxygen 10
0%) into a 3.4 liter aluminum high pressure vessel at a pressure of 120 kg / cm ² , and 1.4 kg / cm 2
^The pressure was reduced to ² , and the pressure regulating valve and the flow regulator provided in the container were adjusted so that the pressure was reduced to flow at a flow rate of 0.5 to 5 liter / min into the oxygen flow path. The inspiratory pressure sensor is installed on the NO flow path in the respiratory tuning gas supply controller and downstream of the NO control valve, and detects the negative pressure change detection sensitivity in the range of 1 to 5 Pa / 10 msec according to the strength of the patient's breathing. Can be set to.

[0017] NO and oxygen control valves were installed in each flow path in the respiratory tuned gas supply regulator. Both control valves are opened 0.1 seconds after the start of inspiration, and the respective supply amounts (when assuming that NO and oxygen are continuously supplied) indicated by the supply flow rate setting dial provided in the respiratory synchronization gas supply controller. According to the flow rate display), the microcomputer was controlled to open and close the solenoid valve so as to open for 0.02 to 0.03 seconds, and NO and oxygen were supplied in a pulsed manner. The total weight of the portable gas supply, including the portable accessories, was approximately 6-7 kg.

Test Example 1 The portable gas supply device described above was used in an experimental system using a model lung shown in FIG. 3, and NO and oxygen were inhaled into the model lung 12 in synchronization with inspiration of the model lung. At the exit side of the model lung, a zirconia oximeter 13 (Aero Monitor AE-280 manufactured by Minato Medical Science Co., Ltd.) and a chemiluminescent nitrogen oxide analyzer 14 (CLM-50 manufactured by Shimadzu Corporation)
0) was connected and used for measurement of NO concentration and oxygen concentration in the model lung. Using a high-pressure vessel containing various concentrations of NO mixed gas, the flow rate of the NO mixed gas was 0.5 liter / mi.
n, the NO concentration was varied in the range of 0 to 400 ppm, and the NO mixed gas and oxygen were inhaled into the model lungs in a pulsed manner under the above-mentioned adjustment conditions under a constant amount of oxygen supply. FIG. 4 shows the relationship between the various NO inhalation concentrations and the NO concentration in the model lung at that time.

The flow rate of the NO mixed gas having a NO concentration of 93 ppm is changed in the range of 0 to 2 liter / min.
Under a fixed amount of oxygen supply, the NO mixed gas and oxygen were inhaled into the model lungs in a pulsed manner under the above-mentioned adjustment conditions. NO
FIG. 5 shows the measurement results of the NO concentration in the model lung with respect to the change in the flow rate of the mixed gas. Medical oxygen gas, flow rate 0-5
Oxygen and NO mixed gas were inhaled into the model lung in a pulsed manner under the above-mentioned adjustment conditions while supplying a fixed amount of NO mixed gas while changing the rate in the range of liter / min. FIG. 6 shows the measurement results of the oxygen concentration in the model lung with respect to the change in the flow rate of oxygen gas.
Shown in The oxygen concentration in the model lung when the inhaled oxygen flow rate is 0 naturally indicates the oxygen concentration in the air.

Comparative Test Example 1 The experiment and measurement were carried out in the same manner as in Test Example 1 except that NO and oxygen were continuously inhaled. FIGS. 4, 5 and 6 show the measurement results of the NO concentration and the oxygen concentration in the model lung.
From Test Example 1 and Comparative Test Example 1, the NO concentration and oxygen concentration in the model lung increased in proportion to the concentration and flow rate of the inhaled gas. The concentration and oxygen concentration were obtained.

Test Example 2 The above portable gas supply device was used for nine healthy persons, and a NO mixed gas with a NO concentration of 400 ppm and a flow rate of 1 liter / min was supplied under a constant amount of oxygen supply under the above-mentioned adjustment conditions. Subject was inhaled. Blood was collected after inhalation for 30, 60, and 90 minutes, and the blood methemoglobin concentration was measured.
FIG. 7 shows the result.

Comparative Test Example 2 An artificial respirator equipped with an adult breathing circuit (servo 900
A nitrogen-diluted NO mixed gas flow path is connected to the air supply flow path C), and the air and the nitrogen-diluted NO mixed gas that have passed through the humidifier are supplied in synchronism with the subject's inhalation via an airtight face mask. A device that was discharged to the outside of the room via a NO ₂ removal device was created and used as a face mask respiratory synchronization gas supply device. Ten days after the end of the experiment in Test Example 2, air containing 40 ppm NO was inhaled at 10 liters / min using the above-mentioned face mask respiratory synchronization gas supply device to the same nine healthy persons. 3 in the same manner as in Test Example 2
Blood was collected after inhalation for 0, 60 and 90 minutes, and the blood methemoglobin concentration was measured. FIG. 7 shows the result.

Using the portable gas supply device of Test Example 2, N
1 liter / mi of NO mixed gas with O concentration of 400 ppm
n using the delivery method of the present invention for inhalation at n and a face mask respiratory synchronization gas supply device which is currently widely practiced.
It was clear that NO absorbed in the body was equivalent to the above-described supply method in which air containing 0 ppm NO was inhaled at 10 liter / min. That is, the effect of inhaling NO using the portable gas supply device was not inferior to the effect of using the conventional face mask respiratory synchronization gas supply device.

Test Example 3 The above portable gas supply device was used for 15 healthy persons,
The flow rate of the NO mixed gas having a concentration of 93 ppm was changed in the range of 0 to 2 liter / min, and the subject was inhaled in a pulsed manner under the above-mentioned adjustment conditions. Cover the subject's mouth and nose with a nasal cannula with an airtight face mask,
Exhaled gas discharged from the subject and gas leaked from the cannula were collected in a 10-liter rubber bag, and the NO concentration was measured using a chemiluminescent nitrogen oxide analyzer 14. FIG.
Shows the average value of the NO concentration in the exhausted gas per subject.

Comparative Test Example 3 The experiment and measurement were performed in the same manner as in Test Example 3 except that NO was continuously inhaled. FIG. 8 shows the average value of the NO concentration in the discharged gas per subject. The NO concentration in the gas discharged from the subject in Test Example 3 was 0.1 ppm or less until the flow rate of NO was 1 liter / min.
The concentration was suppressed to 1/5 or less.

Test Example 4 The above portable gas supply apparatus was used for 15 healthy persons in a room having a capacity of 3000 m ³ , and the NO mixed gas was kept at a constant flow rate of 2 liter / min and the NO concentration was in the range of 0 to 400 ppm. , And the subject was inhaled for 1 hour in a pulsed manner under the above-mentioned adjustment conditions. After the inhalation was completed, the indoor NO concentration and nitrogen dioxide (hereinafter simply referred to as NO ₂ ) concentration were measured using a chemiluminescent nitrogen oxide analyzer 14. FIG. 9 shows the result. NO concentration and NO ₂ concentration in the chamber is suppressed to 20ppb and 5ppb respectively, NO ₂
The occurrence of the occurrence was extremely small.

[0027]

According to the portable nitrogen monoxide-oxygen gas supply apparatus of the present invention and the operation method thereof, a nitrogen dioxide removing apparatus becomes unnecessary, and the whole apparatus can be reduced in size and weight, so that the patient can be at home. You can comfortably receive nitric oxide inhalation therapy while living your daily life. The therapeutic effect can be obtained with the minimum supply amounts of nitric oxide and oxygen according to the patient's condition, and it can be expected to save gas and prevent nitrogen dioxide contamination to the patient and the surrounding environment.

[Brief description of the drawings]

FIG. 1 shows a portable nitric oxide-oxygen gas supply apparatus according to an embodiment of the present invention.

FIG. 2 shows an example of a supply pattern of NO and oxygen in the present invention.

FIG. 3 is a schematic diagram of an experimental system using a model lung.

FIG. 4 is a diagram showing a relationship between an inhaled NO concentration and a NO concentration in a model lung.

FIG. 5 is a diagram showing the relationship between the flow rate of an inhaled NO mixed gas and the NO concentration in a model lung;

FIG. 6 is a diagram showing a relationship between inhaled oxygen flow rate and oxygen concentration in a model lung.

FIG. 7 is a graph showing the relationship between the inhalation time of NO mixed gas and the concentration of methemoglobin in blood.

FIG. 8 is a diagram showing the relationship between the flow rate of the intake NO mixed gas and the exhausted NO concentration;

FIG. 9: Intake NO concentration, indoor NO concentration, and NO ₂
Diagram showing relationship with concentration

[Explanation of symbols]

Reference Signs List 1; nitric oxide cylinder 2: oxygen cylinder 3: nasal cannula 4: respiratory synchronization gas supply controller 5, 6; control valve 7; sensor 8; control valve opening / closing control means 9; supply flow rate setting dial 10; nitric oxide flow Road 11; oxygen flow path 12; model lung 13; zirconia oximeter 14; chemiluminescent nitrogen oxide analyzer 15; one-way valve

Claims (7)

[Claims] 1. A nasal cannula (3); a lightweight nitric oxide cylinder (1) for supplying nitric oxide to the nasal cannula via a nitric oxide flow path (10) and a control valve (5); A light oxygen cylinder (2) for supplying oxygen to the nasal cannula via the tract (11) and the control valve (6), and a sensor (7) for sensing spontaneous breathing of the patient with the nasal cannula, preset A portable nitrogen monoxide-oxygen gas supply device comprising: means (8) for controlling the opening and closing of a control valve according to conditions and a signal from a sensor, and which can be carried and used by a patient. 2. The portable nitric oxide-oxygen gas supply device according to claim 1, wherein a capacitance type differential pressure gauge is used as the sensor (7). 3. A nitric oxide channel (10) and an oxygen channel (1).
3. The portable nitric oxide-oxygen supply device according to claim 1, wherein 1) and 1) are combined in one flow path immediately before the nasal cannula (3). 4. A separate nasal cannula that can be worn simultaneously,
3. The method according to claim 1, wherein the nitric oxide flow path and the oxygen flow path are connected to each other.
A portable nitric oxide-oxygen supply device as described. 5. A method for operating a portable nitric oxide-oxygen gas supply device according to claim 1, wherein
Using nitric oxide diluted with nitrogen as nitric oxide,
A method for operating a portable nitric oxide-oxygen gas supply device, characterized in that: 6. A method for operating a portable nitric oxide-oxygen gas supply device according to claim 1, wherein:
The control valve (5) and / or the control valve (6) are opened according to a spontaneous breathing detection signal from the sensor (7), and the control valve opened after a predetermined time is closed, and nitric oxide and / or oxygen is inhaled during spontaneous breathing. A method for operating a portable nitric oxide-oxygen gas supply device, wherein air is supplied in a pulsed manner within a period of time. 7. A method for operating a portable nitric oxide-oxygen gas supply device according to claim 1, wherein:
The control valve (5) and / or the control valve (6) are opened by the spontaneous breathing detection signal from the sensor (7), and the flow rates of nitric oxide and oxygen are set to a preset flow rate.
And controlling the opening and closing of the control valve (5) and / or the control valve (6) so as to be synchronized with spontaneous breathing, and delivering nitric oxide and / or oxygen in a pulsed manner during the inspiratory time of spontaneous breathing. A method for operating a portable nitric oxide-oxygen gas supply device, characterized in that: