JPH09299485A - Respiration-synchronized oxygen-feeding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a patient to recognize remaining usable time of oxygen by detecting the primary pressure of a compressed oxygen cylinder, calculating the remaining amt. of oxygen and displaying the result. SOLUTION: A cylinder pressure detector 43 provided with a semiconductor pressure sensor is installed by making a branch from a guide pipe between a pressure reducing valve 101 fitted on an oxygen cylinder 1 and a pressure controlling valve 102. The primary pressure of the cylinder 1 is detected thereby and pressure deviation in the cylinder is transferred to an operating means 26 through a conversion circuit 44 as a voltage signal. On the other hand, the value of the vol. of the cylinder 1 is inputted from an outside inputting means 103 and it is transferred to the operation means 26 and a storing part 34 for the set value of the flow rate for a patient. The operating means 26 operates the remaining vol. of oxygen in the cylinder from the inputted information on pressure deviation in the cylinder and the value of vol. of the cylinder and outputs it to a displaying part 45 and it is displayed there. It is possible thereby for the patient to know the remaining usable time of the oxygen cylinder 1 and to prevent oxygen from becoming shortage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breathing gas supply apparatus provided with an automatic opening / closing jig which can be operated according to a breathing cycle of a user. More specifically, the present invention relates to an apparatus for intermittently supplying oxygen or oxygen-enriched gas to a user as a respiratory gas in accordance with a respiratory cycle.

[0002]

2. Description of the Prior Art Oxygen inhalation is one of the most effective treatments for respiratory diseases such as emphysema and chronic bronchitis. In recent years, an oxygen-enriched air supply device or oxygen cylinder has been used for this therapy. It has come to be used. When performing the inhalation therapy at a hospital or at home, an oxygen-enriched air supply device or a large-capacity fixed oxygen cylinder is used, but when the patient goes out such as going to the hospital, a portable lightweight oxygen cylinder is used. Used.

Since it is a cylinder to be carried by patients with respiratory diseases, it must be small and lightweight, and its capacity is also limited.

A pressure gauge is usually attached to such an oxygen cylinder to indicate the amount of oxygen remaining in the cylinder.
In order for the patient to know the remaining usable time of the oxygen cylinder,
At present, it is only possible to roughly infer from the pressure value of the cylinder based on experience in use.

Recently, in order to more efficiently inhale oxygen, oxygen is released only in the initial stage of inhalation, and an automatic opening / closing valve means for stopping the release of oxygen during exhalation is also used, and the oxygen cylinder is used for a long time. Demand valve means such as that of In addition, a control method of supplying only oxygen that is substantially used, such as the initial 1/3 to 1/6 during inhalation, is adopted, and while the usable time of the oxygen cylinder is extended, the oxygen cylinder can be used forever. It is in a state where the user does not understand. Many patients inhale oxygen at different prescribed flow rates at rest and during exertion, and it is more difficult to estimate the oxygen use amount, for example, when exertion and rest are repeated when going out.

As described above, it is difficult to estimate the remaining usable time only from the residual pressure of the oxygen cylinder due to the combined use of the demand valve means. Depending on the usage method, oxygen is consumed more than expected, and oxygen is exhausted on the way out. , There is a risk that oxygen cannot be inhaled.

[0007]

As described above, when a patient carries an oxygen cylinder and uses oxygen-enriched air at the time of going to the hospital or going out, it is necessary to be able to stably inhale oxygen. It is a very important issue for the patient to know the remaining usable time of the oxygen cylinder during use.

[0008]

Means for Solving the Problems As a result of diligent study on such problems, the inventor of the present application has obtained information obtained from means for detecting the primary pressure of a pressurized oxygen cylinder, information on the volume of the oxygen cylinder,
Based on the flow rate information of the flow rate setting means and the opening / closing timing information of the automatic opening / closing valve means of the demand regulator,
It has been found that such a problem can be solved by providing means for calculating the remaining oxygen amount, available time, and means for displaying the result.

That is, according to the present invention, a pressurized oxygen cylinder is provided in a breathing synchronized oxygen supply apparatus in which pressurized oxygen is supplied from an oxygen cylinder to a patient's cannula via a flow rate setting means and an automatic opening / closing valve means of a demand regulator. Based on the information obtained from the means for detecting the primary pressure, the information on the volume of the oxygen cylinder, the information on the flow rate of the flow rate setting means, and the information on the opening / closing timing of the automatic opening / closing valve means of the demand regulator, It is an object of the present invention to provide a respiration-synchronized oxygen supply device having a means for calculating a usable time and a means for displaying the result.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to the drawings as necessary.

FIG. 1 shows a schematic flow chart of a preferred embodiment of the breathing synchronized oxygen supply apparatus of the present invention.

The respiration-synchronized oxygen supply device of the present invention is a device capable of setting the oxygen supply amount and the supply timing in accordance with the oxygen supply amount to be used by the patient, which is determined by the doctor's prescription. It has means for calculating the remaining available time from the speed.

For example, according to the present invention, a pressurized oxygen cylinder is connected to the cylinder at one end, the open type supply means for oxygen is provided at the other end, and the conduit means is provided with an automatic flow path opening / closing means on the way. A breathing gas supply device comprising a demand regulator means for controlling the supply amount of oxygen by controlling the opening / closing time of an automatic flow path opening / closing means, wherein a pressure detecting means is arranged in front of a pressure regulating valve means. Detects the primary pressure of the pressurized oxygen cylinder and calculates the usable time from the cylinder volume value, the flow rate set value, and the control value of the demand regulator, and a means for displaying the result.

As the calculation means, the oxygen consumption amount per unit time is calculated from the set value of the flow rate setter 31 which is the setting means of the oxygen supply amount and the supply control value of the demand valve 3, while the oxygen cylinder 1 and The residual oxygen amount is calculated from the primary pressure value in the cylinder and the volume value of the cylinder 1 obtained from the sensor 43 for measuring the residual pressure in the cylinder provided between the pressure control valves 102, and the remaining usable time of the cylinder 1 is calculated. Including means.

As the sensor for measuring the residual pressure in the cylinder, a capacitance type pressure converter, a differential transformer, a strain gauge type inductance conversion, an electric resistance conversion type pressure converter or the like can be used. In particular, it is preferable to use a semiconductor pressure sensor.

Further, the conduit 5 is provided with a breathing phase detecting means 9 having a function of detecting at least a part of a predetermined phase, and a control means 10 for controlling the demand valve 3.

The control means obtains a breathing cycle or the number of breathing cycles based on the signal sent from the breathing phase detection means, a storage means for storing the relationship between the cannula outlet flow rate and the open time, an oxygen saving rate input and / or storage means. , A prescription flow rate input and / or storage means, an opening time setting means of the automatic flow path opening / closing means, and an opening / closing adjusting means.

The demand cycle, which is the ratio of the opening time of the automatic flow path opening / closing means to one breathing cycle, is calculated by such means.

The primary pressure of the cylinder is measured by the sensor, the pressure data is converted into an electric signal and the signal is sent to a computer. The amount of remaining gas can be calculated from the pressure data in the cylinder and the volume value of the cylinder by software in the computer, and the remaining usable time of the gas in the cylinder can be calculated by the following formula 1 in combination with the prescription flow rate signal.

[0020]

[Equation 1] Usable time (T) = Gas remaining amount / (Set flow rate x Demand cycle)

Further, as another calculating means of the remaining usable time of the present invention, the remaining usable time is calculated based on the information of the pressure fluctuation of the pressurized oxygen cylinder of the cylinder residual pressure sensor 43 within a fixed time. Means can be used. It is possible to store the gas consumption amount within the predetermined time immediately before and calculate the usable time by the following formula 2.

[0022]

[Equation 2] Usable time (T) = Gas remaining amount / Gas consumption within a certain period of time immediately before

The remaining gas amount is represented by the product of the cylinder volume (V) × the cylinder internal pressure (P), and the gas consumption amount in the immediately preceding constant time is the cylinder volume (V) × the immediately preceding constant time. It is a value represented by the product of the pressure drop value (ΔP).

Further, in the present apparatus, the display means 45 for displaying the calculation result calculated by such means can display the prescription flow rate and the cylinder gas remaining amount in addition to the usable time. As the display means, only the digital display that shows the remaining usable time by a number, the analog display using the pointer scale, the bar display that is divided in stages, the graph display such as a pie chart, and the position or section that shows the remaining usable time are displayed. It may be a method of lighting or blinking display, voice display, or a combination thereof.

Further, such means can notify the patient in advance by issuing a notice signal when the remaining amount becomes low. As such a signal, an audio signal, a change in color tone of the display means, a warning lamp lighting or blinking thereof, and the like are preferable. The set value for generating the signal is preferably the remaining usable time of the oxygen cylinder. Further, it may be the pressure value of the oxygen cylinder or the remaining oxygen amount.

The oxygen cylinder and the demand regulator are originally separate devices, and in the device of the present invention, which is usually used by connecting them by a conduit or a tube,
Although separate devices may be used, it is preferable to use both as a unit. In the conventional device, it is necessary to install a lead wire for transmitting a signal from the pressure detection means of the residual pressure in the cylinder to the demand regulator means in parallel with the oxygen delivery conduit. ,
It is possible to omit the lead wire.

[0027]

EXAMPLE An example of the detecting means, the inputting means, the calculating means and the result displaying means will be described with reference to FIG.

FIG. 2 shows an example of a preferred embodiment of the respiratory gas supply apparatus of the present invention. That is, the oxygen emitted from the oxygen cylinder 1 which is a means for generating breathing gas is
A conduit means 5 provided with a maximum flow rate setting device 31 and an automatic flow path opening / closing (valve) means 3 via a pressure reducing valve 101 and a pressure control valve 102.
Through the nasal cannula 7, which is an open-type supply means. The maximum flow rate setting device may be a flow meter such as a normal rotor meter, and has a flow passage restricting function unit such as a plurality of orifices having openings of different sizes. A flow rate setting means for setting the flow rate by switching the parts may be used.

A cylinder pressure detector 43 equipped with a semiconductor pressure sensor provided by branching from a conduit means connecting the pressure reducing valve 101 and the pressure control valve 102 converts the pressure fluctuation in the cylinder into a current, and further converts the current into a current by a conversion circuit 44. The signal becomes a voltage signal.

The volume value of the cylinder used is external input means 1
03, the volume signal and the pressure signal are input to the calculating means 26 to calculate the oxygen remaining amount in the cylinder, and the result is output to the display means 45.

Further, the breathing phase detecting means 9 provided with a diaphragm type minute pressure variation sensor provided in a branch from the conduit means 5 converts the pressure variation in the breath into the variation of the electrostatic capacity, and the conversion in the control means 10. The circuit 12 converts the fluctuation of the electrostatic capacity into an electric pulse signal, and the counting circuit 14 converts the electric pulse signal into a signal of the number of pulses per unit time (for example, 10 msec).

The pulse number signal output from the counting circuit 14 is preferably smoothed by the smoothing circuit 15 to reduce noise. This is conveniently done with the current data and the past few times,
For example, it is achieved by a moving average operation of integrating data of three times and obtaining an average of four data.

Using the digital signal thus obtained, the intake start point detecting means 16 in the CPU 11 of the microcomputer or the like calculates a variation amount of the digital signal with respect to time, that is, a differential value, and the value is predetermined. When it is larger than the value, it is detected as the respiratory start point.
The predetermined value is set by the respiratory detection sensitivity set value storage unit 32, and is preferably set by the input from the external input means 103.

The time between the breathing start time point and the breathing start time point in the breathing cycle immediately before that is measured and stored, and the average breathing cycle for N breathing cycles is calculated by the calculating means 20 as t ₁ . The value of N may be 1, but when using the average value, it is 2
It is appropriately selected within the range of 10 to 10.

Further, the relational pattern of the prescribed flow rate (V), the breathing cycle (t ₁ ) and the opening time (t ₀ ) of the automatic opening / closing valve, which has been obtained in advance for the device, is stored in the general-purpose relational pattern storage unit 23.
To memorize it.

Further, the prescription flow rate (V) is input from the input means 103 and stored in the patient flow rate set value storage section 34 and the required oxygen flow rate storage section 25.

Thus, under the set maximum flow rate, according to the relationship between the cannula outlet flow rate and the opening time of the automatic flow path opening / closing means which is predetermined corresponding to the device characteristics, the value of 1 immediately before intake is obtained.
Opening time set corresponding to a respiratory cycle or respiratory cycle for the inspiration calculated from a plurality of respiratory cycles or respiratory cycles including During this period, the demand regulator opens the automatic flow path opening / closing means 3 to supply oxygen to the patient.

Based on the above results, from the demand cycle, which is the ratio of the automatic flow path opening / closing means 3 to the average breathing cycle, the set flow rate value of the maximum flow rate setting means 31, and the remaining gas amount value in the cylinder, The remaining usable time of the oxygen cylinder is calculated by the equation 1 and the result is output to the display means 45.

Further, if necessary, the oxygen cylinder pressure value and the prescribed flow rate value (V) can be output to the display means.

[0040]

According to the present invention, the remaining usable time of the oxygen cylinder can be easily known, and the risk of running out of oxygen while going out can be avoided. In addition, even if the patient's prescription flow rate and demand cycle are changed, the usable time can be automatically calculated, and by setting a warning signal, it is possible to know the danger before oxygen depletion occurs. Becomes

[Brief description of drawings]

FIG. 1 is a schematic flow chart schematically showing a preferred embodiment of the breathing synchronized oxygen supply device of the present invention.

FIG. 2 is a schematic flow chart schematically showing a preferred embodiment of the breathing synchronized oxygen supply device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Oxygen cylinder 3 Demand valve 5 Extension tube 7 Nasal cannula 9 Respiratory detector 10 Control means 11 Microcomputer 12 Conversion circuit 14 Counting circuit 16 Inspiration start detector 20 Respiratory cycle computing unit 23 Relational pattern storage unit 25 Required oxygen flow rate storage unit 26 Calculation means 31 Maximum flow rate setting device 32 Inhalation detection sensitivity setting value storage unit 33 Patient pattern setting value storage unit 34 Patient flow rate setting value storage unit 41 Tank 43 Semiconductor type cylinder pressure detector 44 Conversion circuit 45 Display means 102 Pressure control valve 103 Power-off / rest / work input means

Claims (5)

[Claims] 1. A primary pressure of a pressurized oxygen cylinder, wherein pressurized oxygen is supplied from an oxygen cylinder to a cannula of a patient via a flow rate setting means and an automatic opening / closing valve means of a demand regulator. A respiration-synchronized oxygen supply device having means for calculating the remaining oxygen amount based on the information obtained from the means for detecting and the information on the oxygen cylinder volume, and means for displaying the result. 2. A primary pressure of a pressurized oxygen cylinder in a respiratory synchronized oxygen supply device, wherein pressurized oxygen is supplied from an oxygen cylinder to a patient's cannula via a flow rate setting means and an automatic opening / closing valve means of a demand regulator. Based on the information obtained from the means for detecting the oxygen volume, the information on the volume of the oxygen cylinder, the information on the flow rate of the flow rate setting means, and the information on the opening / closing timing of the automatic opening / closing valve means of the demand regulator, A breath-synchronized oxygenator having a means for calculating and a means for displaying the result. 3. A primary pressure of a pressurized oxygen cylinder in a breathing synchronized oxygen supply device, wherein pressurized oxygen is supplied from an oxygen cylinder to a patient's cannula via a flow rate setting means and an automatic opening / closing valve means of a demand regulator. A respiration-synchronized oxygen supply device having means for calculating an available time based on information on the differential pressure within a fixed time period obtained from the means for detecting and a means for displaying the result. 4. The warning signal is transmitted when the remaining amount of the oxygen cylinder falls below a set value.
The respiration-synchronized oxygen supply device according to any one of claims 1 to 3. 5. The breathing synchronized oxygen supply device according to claim 1, wherein a warning signal is transmitted when the usable time of the oxygen cylinder becomes equal to or less than a set value.