JPH0975459A - Medical gas blender and supply method and system for medical gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably feed inhalation gases at the preset component gas concentration by adjusting a plurality of types of gases to the flow rate of a gas component corresponding to the preset component gas concentration, measuring the gas concentration of an inhalation gas component in a respiratory circuit for comparison with a reference value, and feeding back the measurement value to a gas supply means. SOLUTION: An operation mode selection, an overall flow rate, NO concentration and oxygen concentration are inputted and determined from the touch panel of a monitor device 22. The flow rates of oxygen, the air and NO based on the preset values are fed from a concentration recording device 23. A control computer calculates the flow rate of sampled inhalation gases (real gases) as well as the concentration of NO and oxygen contained therein, and makes a comparison with the preset values. An operation signal is, then, outputted to a mass flow controller on the basis of the result of the calculation, and the overall flow rate and the flow rates of NO and oxygen are adjusted, thereby controlling the concentration of NO and oxygen. Then, NO and oxygen are mixed immediately prior to the feed thereof to a patient M, and sampled at the after-flow of the mixture for re-measurement with an analysis device 24. The re-measurement results are fed back to the control computer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical gas blender and a medical gas supply method and system. More specifically, the present invention relates to a medical gas blender for supplying various gases useful for medical treatment in a medical field at a preset component gas concentration, and inhaling to a patient for treatment, and a medical gas supply method and system. is there.

[0002]

2. Description of the Related Art In the medical field, it has been practiced for a long time to select various useful gases, supply them at preset component gas concentrations, and inhale them for treatment. Recently, a very small concentration of nitric oxide (hereinafter referred to as NO
Is a specific treatment of pulmonary hypertension, which is a treatment method that selectively expands pulmonary blood vessels to lower pulmonary blood pressure without lowering systemic blood pressure (generally blood pressure) by inhaling Is being watched as. However, in performing this treatment method, NO must be mixed with oxygen or air within a preset concentration range and stably supplied, and nitrogen dioxide (hereinafter referred to as NO ₂₎ , which is more toxic, is required. It is necessary to clear the point that the production of) must be suppressed.

There is a medical gas supply system as shown in, for example, FIG. In this system, the mass flow controller adjusts the flow rate of NO and oxygen (or air) according to the set concentration,
It is mixed and inhaled just before the patient.
Check the O concentration by checking the gas drawn from the patient's mouth with N
It is performed by measuring with an O analyzer. In addition, the exhaled air adsorbs NO and NO ₂ through activated carbon and exhausts it to prevent indoor pollution. According to this system, N
Since the distance from the point of mixing O and oxygen to the patient is short, NO ₂
It is effective in suppressing the production of.

[0004]

However, the above-mentioned conventional system has the following problems. That is, in the conventional system, the result of the NO concentration of the intake gas measured by the NO _X analyzer is not fed back to the flow rate adjustment of the mass flow controller.
Therefore, when the NO concentration is out of the set value, the flow rate must be manually adjusted each time. Moreover, the adjustment cannot be performed in real time, and therefore it is practically difficult to stably supply the NO mixed gas having a preset concentration.

The present invention solves the above-mentioned problems, and it is possible to perform feedback in real time based on the measured value of the concentration of the component gas contained in the inhaled gas, and the inhaled gas can be fed at a preset component gas concentration. An object of the present invention is to provide a medical gas blender that can be stably supplied, and a medical gas supply method and system.

[0006]

Means of the present invention taken to solve the above problems are as follows. According to the first aspect of the present invention, there is provided a medical gas blender, in which one or more kinds of required gases are mixed in accordance with a preset constituent gas concentration of the inhaled gas. A gas supply means capable of supplying the gas to the breathing circuit or the inhaler by adjusting the flow rate, and a gas control means for measuring the component gas concentration of the inhaled gas in the breathing circuit and comparing it with a reference value, and feeding back to the gas supplying means. , Is a medical gas blender.

A second aspect of the present invention is a medical gas supply method, which adjusts the flow rate of the component gas in accordance with a preset component gas concentration of the inhaled gas,
A medical gas supply method, comprising: supplying to a breathing circuit; analyzing a concentration of a component gas of inhalation gas in the breathing circuit; and feeding back the analysis result to adjust a flow rate of the component gas. is there.

According to a third aspect of the present invention, there is provided a medical gas supply system, which comprises a breathing circuit and one or more kinds of required gases, and a preset component gas concentration of the inhaled gas. The gas flow rate of the component gas is adjusted according to the above, and the gas supply means capable of supplying the breathing circuit or the inhaler and the concentration of the component gas of the inhalation gas in the breathing circuit are measured and compared with the reference value, and the gas And a gas control unit that feeds back to the supply unit.

The gas supply means corresponds to a preset component gas concentration of the intake gas, for example, a gas in which NO and oxygen, NO and air, or NO, oxygen and air are mixed. The flow rate of one type of component gas (for example, NO only) can be adjusted, or the flow rates of a plurality of types of component gas (for example, NO and oxygen) can be adjusted. You can also set Then, the component gas whose flow rate is adjusted is appropriately mixed with another gas (for example, air) to form the intake gas, but the component gas whose flow rate is adjusted may be the intake gas.

The breathing circuit may be provided with a ventilator, but it is not necessary if spontaneous breathing is possible. Further, the breathing circuit is provided with an exhausting means for discharging the exhaled air to the outside through a means (for example, activated carbon) capable of adsorbing or reducing the harmful component gas when the exhaled air contains the harmful component gas. If all the constituent gases in the exhaled air are harmless, or if they are harmful but the concentration is extremely low below the recommended value such as the working environment standard concentration, exhaled air may be set to be discharged as it is. .

The gas control means has a measuring means suitable for each of the component gases to be analyzed. For example, when the component gas is NO, the reduced pressure chemiluminescence type NO is used.
Various known measuring devices such as an _X analyzer and a magnetic force type oxygen concentration meter when the component gas is oxygen are used. Since the suction gas is humidified by the humidifier, a dehumidifier for dehumidifying the suction gas before measurement can be provided. Further, the gas control means includes an arithmetic unit (computer) that compares the analysis result with a reference value.

(Working) cylinder filled with component gas,
Alternatively, the component gas is introduced into the gas supply means from the gas pipe in the hospital. Initially, the flow rate of the component gas is adjusted based on, for example, a theoretical value so that the produced intake gas has a preset component gas concentration. The component gas of which the flow rate is adjusted is supplied to the patient as a suction gas by being mixed alone or by mixing a plurality of kinds of gases, or by being mixed with other gas such as air in the breathing circuit.

The concentration of the component gas in the intake gas supplied by the gas supply unit is analyzed by the gas control unit, and the analysis result is fed back to the gas supply unit to adjust the flow rate of the component gas in real time. As a result, it becomes possible to stably supply the inhalation gas having the preset component gas concentration.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the embodiments shown in the drawings. 1 is an explanatory view showing an embodiment of a medical gas supply system according to the present invention, FIG. 2 is a front view of a gas blender, FIG. 3 is a side view of the gas blender, and FIG. 4 is a state in which a back plate is opened. A rear view and FIG. 5 are flow sheets of the gas blender. Reference numeral S denotes a medical gas supply system, which includes a breathing circuit 1 and a gas blender 2.
In the present embodiment, the medical gas supply system S is a NO supply system.

The breathing circuit 1 includes an air supply pipe 10.
A mask 11 to be attached to the mouth of the patient M is provided at one end of the air supply pipe 10. Y near the mask 11 of the air supply pipe 1
The exhalation tube 12 is connected through a mold connector. Exhalation tube 1
An exhalation valve 13 is provided at the tip of 2, and the expiratory tube 12 is connected to the inspiratory tube 5. An adsorption device 51 for removing NO and NO ₂ gas is provided at the tip of the intake pipe 5. A ventilator 15 is connected to the other end of the air supply pipe 10 with a humidifier 14 interposed. The ventilator 15 has an oxygen port 16 and an air port 1 which are provided in the hospital.
Each gas is supplied from 7.

The gas blender 2 comprises an NO pressure adjusting / switching device 21, which is a gas supply means, a main operation / monitor device 22, a gas extraction / concentration recording device 23, and an analyzer 24, which is a gas control means. ing. The main operation / monitor device 22 is equipped with a monitor 221 and various settings can be made using a touch panel. On the front surface of the gas extraction / concentration recording device 23, a NO extraction connection part 231, an oxygen / air mixed gas extraction connection part 232, and a recording device 235 for recording an analysis value are provided. In addition, an air connection portion 233 and an oxygen connection portion 234 for introducing the respective gases from the oxygen port 16 and the air port 17 are provided on the side portion.

In FIG. 5, REG is a pressure regulator,
FT is a filter, MV is an electric ball valve, BV is a three-way valve, PS is a pressure switch, MFC is a mass flow controller, CV is a check valve, and PX is a pressure oscillator. To the analyzer 24 is provided with a vacuum-type chemiluminescent NO _X analyzer for measuring the concentration NO, the magnetic force type oxygen concentration meter for measuring the concentration of oxygen. Each of the above devices is erected on a table 20 with casters. Also, on the back of each of the above devices,
Aluminum cylinder 2 filled with NO / N ₂ gas
Two 6 are accommodated.

In the present embodiment, one end side of the gas supply tube 3 is connected to the NO extraction connection portion 231. The other end of the gas supply tube 3 is connected to the ventilator 15 side of the connection part of the expiratory tube 12 of the air supply tube 10. Further, one end side of the sampling tube 4 is connected between the connection part of the exhalation pipe 12 and the connection part of the gas supply tube 3 of the air supply pipe 10. The other end side is connected to a sample intake port (not shown) of the analyzer 24.

(Operation) FIG. 6 is a control block diagram of the medical gas supply system according to the present invention, FIG. 7 is a control flowchart of the control computer, and FIG. 8 is a supply state of inhaled gas by the gas blender during spontaneous breathing. FIG. The operation of the present embodiment will be described with reference to FIGS. In the medical gas supply system S, four types of operation modes can be selected by operating the touch panel on the monitor 221 of the gas blender 2. Each operation mode is (1) ventilator combined mode, (2) blender concentration control mode, (3) blender flow rate control mode,
(4) Manual mode. Next, each mode will be described with reference to the drawings.

(1) Ventilator Combined Mode In this mode, as shown in FIG. 1, air and oxygen are supplied from the ventilator (ventilator) 15 to the air supply pipe 10 of the breathing circuit 1.
Supplied to Only NO (including N ₂ gas) having a regulated flow rate is supplied from the gas blender 2 and mixed with air and oxygen immediately before the patient M in the air supply pipe 10.

Next, the control of the medical gas supply system S will be described. The main operation, the touch panel of the monitor 221 of the monitor device 22, select the operation mode and input and set the NO concentration. NO is supplied from the gas extraction / concentration recording device 23 at a flow rate based on the set value, and the control computer compares the NO concentration in the sampled inhalation gas (actual gas) with the set value, and performs calculation to operate. A signal is sent to the mass flow controller to adjust the flow rate and control the concentration. The NO whose flow rate has been adjusted is mixed with the supply air from the artificial respirator 15 and is sampled as an inhaled gas from the subsequent flow. Then, the concentration is measured by the analyzer 24 and sent to the control computer as data.

In the ventilator combined mode, by using the ventilator 15 which is a routine as the breathing assist as described above, various breathing assisting functions of the ventilator 15 can be used as they are. Highly safe because the concentration of component gas can be monitored. Incidentally, a vacuum-type chemiluminescent NO _X analyzer for NO concentration measurement that is provided to the analyzer 24, the magnetic force type oxygen concentration meter for oxygen concentration measurement sensitivity is excellent, the sampling may be small. Therefore, the breathing circuit 1 is not adversely affected. Further, NO can be mixed at an arbitrary timing, and since NO is mixed in the downstream of the ventilator 15, there is an advantage that the inside of the ventilator having weak corrosion resistance is not damaged.

(2) Blender Concentration Control Mode This mode is applied to a spontaneously breathing patient who does not need to use the ventilator 15. Oxygen, air, and NO are supplied from the gas blender 2 and immediately before the patient M. Mix to make inhaled gas. Next, the control will be described with reference to the explanatory diagram shown in FIG. The main operation and the touch panel of the monitor 221 of the monitor device 22 are used to select the operation mode and input and set the total flow rate, NO concentration, and oxygen concentration. Oxygen, air and NO are supplied from the gas extraction / concentration recording device 23 at a flow rate based on the set values, and the flow rate of the sampled intake gas (actual gas) and the concentrations and settings of NO and oxygen in the intake gas are sampled by the control computer. Compare the values,
The calculation is performed and the operation signal is sent to the mass flow controller to adjust the overall flow rate and the flow rates of NO and oxygen to control the concentrations of NO and oxygen. Oxygen, air, and NO whose flow rates have been adjusted are mixed just before the patient M. Then, it is sampled as a suction gas from the subsequent flow, the concentration and the flow rate are measured by the analyzer 24, and sent to the control computer as data.

The blender density control mode is particularly useful when the ventilator 15 has no space and cannot be immediately prepared. That is, since oxygen, air, and NO are feedback-controlled, stable supply is possible for a long period of time, and there is no particular problem as long as the patient M can spontaneously breathe. Further, since the ventilator 15 is not used, the operation is easy and there is an advantage that a space around the bed is not taken.

(3) Blender flow rate control mode In this mode, like the blender density control mode,
It is applied to spontaneously breathing patients who do not need to use the ventilator 15.
O is supplied at a constant flow rate and mixed immediately before the patient M to form an inhaled gas, but the component gas concentration feedback control is not performed. The main operation and the touch panel of the monitor 221 of the monitor device 22 are used to select the operation mode and input and set the total flow rate, NO concentration, and oxygen concentration. Oxygen, air, and NO at the flow rates calculated based on the set values from the gas extraction / concentration recording device 23 are supplied at a fixed flow rate, and are mixed just before the patient M.

The blender flow rate control mode is useful when there is no time to warm up the analyzer 24 (generally, about one hour is required), such as when urgent administration is required. Further, since feedback control of the component gas concentration is not performed, there is an advantage that the response is quick and stable. Further, since the ventilator 15 is not used, the operation is easy and the space around the bed is not taken up, which is the same as the blender concentration control mode.

(4) Manual mode In this mode, the flow rates of air, oxygen and NO can be directly input and set, and sequential adjustment is possible. The operation mode is selected by the main operation and the touch panel of the monitor 221 of the monitor device 22, and air, oxygen, NO is selected.
Input and set the flow rate of. Oxygen, air, and NO having a flow rate based on a set value are supplied from the gas extraction / concentration recording device 23, and mixing is performed immediately before the patient M.

In the manual mode, for example, when the main flow of the ventilator 15 is irregular when used together with an anesthesia machine, the feedback control of the concentration of the component gas by the analyzer 24 may not be stable. In such a case, By adjusting the flow rate based on the experience of the user, it is possible to supply the inhaled gas having a stable component gas concentration.

Next, a main operation, a touch sensor panel (hereinafter referred to as a touch panel) operation screen of the monitor 221 of the monitor device 22 will be described. 9 is an explanatory view showing an initial screen of the operation touch panel of the gas blender, FIG. 10 is an explanatory view showing a menu screen, FIG. 11 is an explanatory view showing a setting screen, FIG. 12 is an explanatory view showing a monitor screen, and FIG.
3 is an explanatory view showing an alarm monitoring screen. Touching any part of the initial screen of FIG. 9 brings up the menu screen of FIG. There are three selection menus, a. Setting concentration and flow rate, b. Concentration and flow monitoring, c. It is alarm monitoring.

Selection Menu a. Touching brings up the setting screen in FIG. On the setting screen, the selection menu d. e.
f. g. Each operating mode can be set by touching. d. When the combined ventilator mode is selected, the h. The setting section of can be set, and l.
You can enter with the numeric keypad. e. Blender density control mode of f. When the blender flow rate control mode of is selected, i. The setting section of can be set, and l.
You can enter with the numeric keypad. And g. If the manual mode is selected, j. The setting section of can be set, and l. You can enter with the numeric keypad. Note that k. By touching, it is possible to move to the menu screen of FIG. 10 or the monitor screen of FIG. 12 described next.

B. Touch to display the monitor screen in Figure 12. On the monitor screen, m. Is a monitor unit that displays the measured values of the component gas concentrations in a graph over time (for example, in units of 1 second). The n. Is a flow checker that displays the remaining amount and supply state of NO, o. Is a mode display unit for displaying the operation mode. Also, p. The set value and the measured value are sequentially displayed on. Note that k. By touching, it is possible to move to the menu screen of FIG. 10 or the setting screen described above.

C. Touch to display the alarm monitoring screen in FIG. On the alarm monitoring screen, a buzzer sounds when an abnormality occurs in the concentration or flow rate of each component gas, and r. An alarm is displayed in the alarm summary of. In this alarm summary, when there are a plurality of alarms, important ones are prioritized and displayed in order. There are various types of alarms, and the main monitoring contents are high intake pressure, large concentration deviation, high NO concentration, low oxygen concentration, low inlet gas pressure, instrument malfunction, and the like. Note that k. By touching, it is possible to move to the menu screen of FIG. 10 or the online help screen (not shown). The present invention is not limited to the illustrated embodiment, and various modifications are possible within the scope of the claims.

[0033]

As is apparent from the above description, according to the present invention, the concentration of the component gas in the intake gas supplied by the gas supply means is analyzed by the gas control means, and the result of this analysis is analyzed by the gas supply means. Can be fed back to adjust the flow rate of the component gas in real time. As a result, it becomes possible to stably supply the inhalation gas having the preset component gas concentration.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a medical gas supply system according to the present invention.

FIG. 2 is a front view of a gas blender.

FIG. 3 is a side view of the gas blender.

FIG. 4 is a rear view showing a state where a back plate of the gas blender is opened.

FIG. 5 is a gas blender flow sheet.

FIG. 6 is a control block diagram of the medical gas supply system according to the present invention.

FIG. 7 is a control flowchart of the control computer.

FIG. 8 is an explanatory diagram showing a supply state of inhaled gas by a gas blender during spontaneous breathing.

FIG. 9 is an explanatory diagram showing an initial screen of an operation touch panel of the gas blender.

FIG. 10 is an explanatory diagram showing a menu screen of the operation touch panel.

FIG. 11 is an explanatory diagram showing a setting screen of the operation touch panel.

FIG. 12 is an explanatory diagram showing a monitor screen of an operation touch panel.

FIG. 13 is an explanatory diagram showing an alarm monitoring screen of the operation touch panel.

FIG. 14 is an explanatory diagram showing an example of a conventional medical gas supply system.

[Explanation of symbols]

 S Medical gas supply system 1 Breathing circuit 10 Air supply pipe 11 Mask 12 Exhalation pipe 13 Exhalation valve 14 Humidifier 15 Ventilator 16 Oxygen inlet 17 Air inlet 2 Gas blender 20 Castor stand 21 NO pressure adjustment, switching device 221 Monitor 22 Main operation, Monitoring device 23 Gas extraction / concentration recording device 231 NO extraction connection 232 Connection mixture of oxygen and air mixed gas extraction 233 Air connection 234 Oxygen connection 235 Recording device 24 Analysis device 26 Cylinder 3 Gas supply tube 4 Sampling tube 5 Intake tube 51 Adsorption device

Claims (3)

[Claims] 1. A medical gas blender, wherein the gas blender adjusts the flow rate of one or more kinds of required gas in accordance with a preset constituent gas concentration of the inhaled gas. A gas supply means that can supply the breathing circuit or the inhaler, and a gas control means that measures the concentration of the constituent gas of the inhalation gas in the breathing circuit, compares it with a reference value, and feeds it back to the gas supply means. A medical gas blender characterized by being 2. A medical gas supply method, which comprises adjusting a flow rate of a component gas according to a preset component gas concentration of inhalation gas and supplying the same to a breathing circuit, and a breathing circuit. A method for supplying medical gas, comprising: analyzing the concentration of the component gas of the inhaled gas therein; and feeding back the analysis result to adjust the flow rate of the component gas. 3. A medical gas supply system, which comprises a breathing circuit and one or more kinds of required gases, the constituent gas of which corresponds to a preset constituent gas concentration of inhaled gas. Gas control that adjusts the flow rate and that can supply gas to the breathing circuit or the inhaler, and gas control that measures the component gas concentration of inhalation gas in the breathing circuit, compares it with a reference value, and feeds it back to the gas feeding means. A medical gas supply system comprising: