JP2006198004A - Oxygen concentrator and method for controlling it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oxygen concentrator which can be used safely by sensing the disconnection of a respirator for use with the respirator by connection to it. <P>SOLUTION: A pressure sensor for measuring the oxygen pressure in the oxygen concentrator monitors the pressure within a joint connected to the respirator, and the detected pressure is compared with a set pressure. When the detected pressure is lower than the set pressure, a time while the detected pressure is lower than the set pressure is measured. When the measured time is a predetermined time (for example, 30 seconds) or more, the connection between the oxygen concentrator and the respirator is determined to be disconnected, and the disconnection is reported by an alarm or the like. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an oxygen concentrator for supplying oxygen by connecting to a ventilator that semi-forcibly promotes lung ventilation to a patient who is difficult to discharge carbon dioxide in normal breathing due to hypercapnia etc. In particular, the present invention relates to an oxygen concentrator that can be used safely by monitoring the connection state when connected to a ventilator and a control method thereof.

  The oxygen concentrator is used as a device for supplying oxygen to a patient in home oxygen therapy for chronic respiratory diseases. For example, in Japanese Patent Laid-Open No. 2000-262619, oxygen concentration by removing nitrogen from air and separating and using oxygen by an adsorption method using zeolite as an adsorbent that permeates oxygen in the air and selectively adsorbs nitrogen. An apparatus is disclosed. In this oxygen concentrator, the air taken in from the air intake is compressed by a compressor, cooled by a heat exchanger, etc., and then sent to an adsorption tower filled with an adsorbent to remove nitrogen gas. . The separated oxygen gas is controlled in pressure and flow rate via a pressure reducing valve and a flow rate setting device, and subsequently humidified by a humidifier, and then supplied to a patient via a conduit such as a cannula. In the above oxygen concentrator, it is described that the flow rate of supplied oxygen is monitored using a flow rate sensor so that oxygen can be stably supplied to a patient. In addition, in the Japanese Patent Application Laid-Open No. 2003-1778, the present inventors continuously supply a predetermined amount of humidified oxygen having a predetermined pressure to a patient through a tube inserted into a patient's nose from a conduit such as a cannula. An oxygen concentrator is disclosed. In this oxygen concentrator as well, it is described that a predetermined amount and a predetermined pressure of oxygen are monitored stably using a flow rate sensor and a pressure sensor.

As described above, when the oxygen concentrator is used alone, the humidified oxygen is released into the atmosphere from a tube or the like inserted into the patient's nose, and the patient inhales the humidified oxygen when breathing. Therefore, the supply oxygen is monitored so as to be stably supplied so that the necessary oxygen can be absorbed.
JP 2003-235817 A JP-A-5-2000303

  In addition to using the oxygen concentrator alone as described above, for example, when mixed with air, for example, an oxygen concentrator supplying oxygen is connected to a ventilator supplying air. It may be used in nasal mask positive pressure ventilation therapy. However, when using the oxygen concentrator connected to a ventilator, the method of use differs from the case of using the oxygen concentrator alone, so when using the oxygen concentrator as described above alone The monitoring method cannot be applied. Hereinafter, this point will be described.

  Nasal mask positive-pressure artificial respiration therapy was introduced as a method of artificial respiration for chronic respiratory failure with hypercapnia and was later widely applied to neurological diseases, pulmonary tuberculosis sequelae, emphysema, etc. Currently, chronic respiratory failure It is considered effective not only for acute respiratory failure. The respirator used for the nasal mask positive pressure respirator is, for example, a respirator body 1100 for supplying air as shown in FIG. 11A, a humidifier 1110, and a nasal mask 1120 that is hermetically fixed to the patient's nostril. And the connection tube 1130, and using the first mode or the second mode shown in FIG. 11B, it is difficult to breathe spontaneously while periodically changing the discharge pressure composed of inspiratory pressure (IPAP) and expiratory pressure (EPAP). The patient is forced to ventilate the air. Here, the first mode is a mode that synchronizes with the patient's spontaneous breathing and performs positive pressure ventilation with the patient's spontaneous breathing as a trigger, and the second mode is a strength that ignores the patient's spontaneous breathing. Ventilation mode. These discharge pressures are adjusted based on the patient's ability to accept and the gas value in the blood. For example, when the patient's stomatal resistance is high or when the patient supplies a lot of oxygen, the inspiratory pressure is increased. In order to reduce the ventilation volume, adjustments such as raising the expiratory pressure are made when it is desired to increase the ventilation volume. However, if the intake pressure is too low, the amount of re-inhalation of intake increases and the ventilation efficiency decreases, so the intake pressure is set to 2 to 4 cmH 2 O, for example.

  However, since the ventilator can adjust the amount of oxygen only by the pressure of the air supplied to the patient, if the patient needs a high concentration of oxygen, the oxygen of that concentration may not be supplied at the required pressure. It is done. Therefore, in such a case, when the oxygen concentrator described above is connected to a ventilator and used, the air from the ventilator and the oxygen from the oxygen concentrator are mixed to prepare a desired concentration. This is considered to be a useful method because the oxygen is supplied to the patient.

  However, when the oxygen concentrator is used in connection with a ventilator, the use conditions are different from the case where the oxygen concentrator is used alone as shown below. That is, when the oxygen concentrator is used alone, oxygen supplied to the patient is continuously released from the tube inserted into the patient's nose into the atmosphere around the nose. On the other hand, when using an oxygen concentrator connected to a ventilator, the oxygen supplied from the oxygen concentrator is mixed with the air from the ventilator, and the mixed gas is sealed in the patient's nostril. Supplied to the patient through a fixed nasal mask. At this time, the mixed gas is supplied to the patient only when the pressure of the mixed gas becomes the inspiratory pressure shown in FIG. 11B, and the mixed gas is not supplied at the expiration pressure. In this way, when using an oxygen concentrator connected to a ventilator, the method of use differs from the case of using the oxygen concentrator alone, so supply when using the oxygen concentrator alone The oxygen monitoring method cannot be used.

  However, even when the oxygen concentrator is used in connection with a ventilator, the oxygen concentrator may be detached from the ventilator during use. It is necessary to prepare.

  The present invention has been made starting from solving the above-mentioned problems of the prior art, and its purpose is to provide a ventilator as used in, for example, nasal mask positive pressure ventilation therapy. The present invention provides an oxygen concentrator that can be used safely by monitoring the connection state with a ventilator when the oxygen concentrator is connected and used, and a control method therefor.

  In order to achieve the above object, an oxygen concentrator according to an embodiment of the present invention has the following configuration. That is, an oxygen concentrator having adjustment means for adjusting the pressure and flow rate of oxygen from an oxygen supply source and supplying the oxygen from an oxygen outlet, and mixing the adjusted oxygen with air from a ventilator A connecting means for connecting the oxygen outlet portion and the ventilator for supply to a patient; and when the oxygen outlet portion and the ventilator are connected by the connecting means, Pressure detecting means for detecting pressure, and monitoring means for monitoring a connection state with the ventilator based on the detected pressure.

  Here, for example, it is preferable that the connecting means includes a telescopic tube connected to the oxygen outlet portion.

  Here, for example, the ventilator has a hermetic mask that is attached to the nostril of the patient and supplies the air to the patient, and the connecting means is the hermetic mask by the telescopic tube. It is preferable to connect with the hermetic mask of the ventilator so that the conditioned oxygen and the air are mixed together.

  Here, for example, it is preferable that the pressure detection means is disposed on the upstream side of the oxygen outlet portion.

  Here, for example, the monitoring means compares the pressure detected by the pressure detection means with a set pressure, and determines that there is no pressure fluctuation when the detected pressure falls below the set pressure; A time measuring means for measuring a period in which there is no pressure fluctuation when the pressure fluctuation determining means determines that there is no pressure fluctuation; and if the period in which there is no pressure fluctuation exceeds a predetermined period, And determining means for determining that the connection state is abnormal.

  Here, for example, the predetermined period is preferably any value from 5 to 60 seconds.

  Here, for example, it is preferable to further have an informing means for informing the abnormality of the connection state between the oxygen outlet and the ventilator.

  Here, for example, it is preferable that the notification means notifies the abnormality of the connection state with the ventilator using sound and / or light.

  Here, for example, the apparatus preferably further includes a humidifying unit, and the oxygen supplied from the oxygen supply source is preferably humidified by the humidifying unit and supplied to the connecting unit as humidified oxygen.

  In order to achieve the above object, a method for controlling an oxygen concentrator according to an embodiment of the present invention has the following configuration. That is, to adjust the pressure and flow rate of oxygen from the oxygen supply source and supply from the oxygen outlet, and to supply the adjusted oxygen to the patient by mixing with the air from the ventilator, Connecting means for connecting the oxygen outlet part and the ventilator, and pressure detecting means for detecting the pressure in the connecting means when the oxygen outlet part and the ventilator are connected by the connecting means And a monitoring means for monitoring a connection state with the ventilator based on the detected pressure, wherein the oxygen outlet and the ventilator are connected by the connecting means. A pressure detecting step for detecting the pressure in the connecting means, and a monitoring step for monitoring a connection state with the ventilator based on the detected pressure. Craft Compares the pressure detected by the pressure detection step with a set pressure, and determines that there is no pressure variation when the detected pressure falls below the set pressure, and the pressure variation determination step When it is determined that there is no pressure fluctuation, the time measuring process for measuring a period in which there is no pressure fluctuation, and when the period in which there is no pressure fluctuation exceeds a predetermined period, the connection state with the ventilator is abnormal It is characterized by having the determination process determined.

  In order to achieve the above object, a control program for controlling an oxygen concentrator according to an embodiment of the present invention has the following configuration. That is, to adjust the pressure and flow rate of oxygen from the oxygen supply source and supply from the oxygen outlet, and to supply the adjusted oxygen to the patient by mixing with the air from the ventilator, Connecting means for connecting the oxygen outlet part and the ventilator, and pressure detecting means for detecting the pressure in the connecting means when the oxygen outlet part and the ventilator are connected by the connecting means And a control program for controlling the oxygen concentrator having monitoring means for monitoring the connection state with the ventilator based on the detected pressure, wherein the connecting means causes the oxygen outlet and the artificial respiration to be controlled. When a ventilator is connected, a program code for executing a pressure detecting step for detecting a pressure in the connecting means and a connection with the ventilator based on the detected pressure. A program code for executing a monitoring step for monitoring the state, and the program code for executing the monitoring step compares the pressure detected by the pressure detection step with a set pressure and detects the detected The program code for executing the pressure fluctuation determining step for determining that there is no pressure fluctuation when the pressure falls below the set pressure, and the pressure fluctuation when the pressure fluctuation determining step determines that there is no pressure fluctuation. A program code for executing a timing process for measuring a non-period and a determination process for determining that the connection state with the ventilator is abnormal when the period without the pressure fluctuation exceeds a predetermined period And a program code for performing the processing.

  In order to achieve the above object, a computer-readable storage medium according to an embodiment of the present invention stores the control program described above.

  According to the present invention, when the oxygen concentrator is connected to the ventilator as in the case of using nasal mask positive pressure ventilation, the connection state with the ventilator is monitored and used safely. It is possible to provide an oxygen concentrator that can be used and a control method thereof.

  A preferred embodiment of an oxygen concentrator according to the present invention will be described below with reference to the drawings.

[Features of the present invention]
The present invention provides an oxygen concentrator used by connecting to a ventilator such as a nasal mask positive pressure ventilator and a control method thereof, and the oxygen concentrator is used by connecting to a ventilator. In this case, it is characterized in that it can be used safely by monitoring the connection state with the ventilator. The oxygen concentrator of the present invention is used by connecting to a ventilator that forcibly supplies air to a patient or the like who has difficulty in spontaneous breathing. The humidified oxygen from is mixed and supplied. Therefore, when the oxygen concentration required by the patient is insufficient with the air from the ventilator, the oxygen concentration required by the patient is adjusted with the patient's ability to accept the patient, the pressure and supply rate suitable for the patient's blood pressure gas value. Can be supplied. In the present oxygen concentrator, a pressure sensor used for detecting the supply pressure of oxygen can be used in combination to constantly monitor the pressure at the connection with the ventilator. For this reason, when connected to a ventilator, the connection pressure continuously measured is compared with the set pressure (discharge pressure fluctuation monitoring pressure), and the measured pressure falls below the set pressure for a predetermined period. If this happens, it can be determined that the oxygen concentrator has been removed from the ventilator for some reason, and the disconnection can be notified. Therefore, when this oxygen concentrator is used by being connected to a ventilator, it can accurately cope with a situation where the oxygen concentrator is disconnected from the ventilator. Therefore, the oxygen concentrator of this embodiment can be used safely when used in connection with a ventilator.

[Configuration of oxygen concentrator: Fig. 1]
FIG. 1 is a block diagram showing an example of the configuration of an oxygen concentrator corresponding to an embodiment of the present invention. As shown in FIG. 1, the air taken into the apparatus is debris removed by a dustproof filter 101 and an intake filter 102, compressed by a compressor 105 via a silencer 103, and then cooled by a heat exchanger 106 or the like. Is done. The cooled air is sent to an adsorption cylinder 108 filled with an adsorbent via a switching valve 107 that switches a pipe flow path.

  Gas separation is performed in the adsorption cylinder 108, and the generated concentrated oxygen gas is temporarily sent to the product tank 111, and then the pressure and flow rate are controlled via the pressure regulator 112 and the flow rate regulator 115. (At this time, the oxygen concentration is detected by the oxygen concentration sensor 114), and is humidified appropriately through the humidifier 116. A pressure sensor 117 is installed between the humidifier 116 and the flow controller 115 to detect the pressure of oxygen sent to the humidifier. The humidified oxygen is supplied to the patient via the oxygen outlet 205 and the flexible extension tube 120. When this oxygen concentrator is used connected to a ventilator, the flexible extension tube connecting part 121 is connected to the ventilator (see FIG. 3, when the mixing part is a nasal mask). For example, as shown in FIG. 4 and FIG.

  When this type of oxygen concentrator is small, the adsorption cylinder 108 is composed of one or two, and is switched by a switching valve 107 to perform adsorption / desorption. For example, when the adsorption cylinder 108 is composed of two tubes, one part of the concentrated gas is used as product gas during the adsorption process, and the other gas is routed to the other adsorption cylinder 108. The gas used for regeneration and repressurization of zeolite in the adsorption cylinder 108 is used. Before adsorption breakthrough in the adsorption cylinder 108 during the adsorption process occurs, the switching valve 107 is switched to the other and the same cycle is repeated to continuously generate and supply concentrated gas.

[Appearance of oxygen concentrator: Fig. 2A]
FIG. 2A shows an appearance of the oxygen concentrator described in FIG. 1 as viewed from the front. Here, 200 represents an oxygen concentrator main body (hereinafter referred to as main body 200). The main body 200 mainly includes a housing portion 214a and a cover portion 214b at the top of the housing. Reference numeral 201 denotes a flow monitor that represents the operation status of the main body 200. 115 is a flow rate setting dial for setting the oxygen flow rate. The flow rate setting dial 115 is provided on the back side of the recess 202 formed in the cover 214b.

  203a is a power switch for switching operation / stop of the main body 200. The power switch 203a is provided on the back side of the recess 203b formed in the cover 214b, and is installed so as not to protrude from the surface of the cover. However, the power switch 203a is difficult to be pressed. Reference numeral 116 denotes a humidifier, and reference numeral 116a denotes a cap portion of the humidifier. 205a is an oxygen output port for connecting the extension tube 120.

  Reference numeral 206 denotes an alarm unit for notifying a power failure, an abnormality in the apparatus, or an abnormality when the main body 200 is connected to a ventilator 300 described later (for example, the extension tube 120 is disconnected from the ventilator 300). The alarm unit 206 incorporates a check lamp, a buzzer, a speaker for outputting a message and / or a light for flashing to notify the abnormality. Reference numeral 207a denotes a flow rate display unit for displaying the flow rate set by the flow rate setting dial 115. The flow rate display unit 207a is provided on the back side of the recess 207b formed on the right side of the humidifier 116 when the main body 200 is viewed from the front as shown in the figure. The flow rate display unit 207a is configured by segment LEDs, and is configured to be able to control the luminance according to the brightness (illuminance) of the installation location.

  Reference numeral 208 denotes a display changeover switch for switching the contents displayed on the flow rate display unit 207a. When the switch 207 is pressed, the display unit displays the usage time for 5 seconds, for example.

  Reference numeral 212 denotes a caster, which is fixed to the four corners of the bottom surface of the main body 200. The operator can move or lift the main body 200 by gripping these handles 213 at the time of transporting on the floor surface using the casters 212 or installing the main body 200. It has become.

  214a is a metal or wooden casing. The casing 214a accommodates the compressor 105, the heat exchanger 106, the switching valve 107, the adsorption cylinder 108, the product tank 111, and the like shown in FIG. Reference numeral 214b denotes a cover that covers an upper portion of the casing 214a, and reference numeral 219 denotes a flat front decorative panel that covers the front surface from the floor surface.

[Control configuration of oxygen concentrator: Fig. 2B]
FIG. 2B is a block diagram showing a control configuration of the oxygen concentrator 200. In FIG. 2B, reference numeral 402 denotes a ROM that stores various control programs and data, 403 denotes a RAM that stores various data and is used as a work area of the CPU 401, 404 denotes a display unit, and 405 denotes switches. Reference numeral 406 denotes sensors mounted in the main body 200, and includes an oxygen concentration sensor 114, a pressure sensor 117, and the like. A CPU 401 controls display contents of the display unit 404 to detect pressing of various switches included in the switches 405 and detects outputs from various sensors included in the sensors 405 and writes them to the RAM 403. Based on the control program stored in the ROM 402, each part of the apparatus such as the operation of the flow monitor 201 and the alarm unit 206 is controlled.

[Connection between ventilator and oxygen concentrator: Fig. 3]
Next, referring to FIG. 3, the oxygen concentrator 200 corresponding to the present invention described in FIG. 1 is connected to an auxiliary ventilator that promotes ventilation of a patient such as a respiratory failure patient, and nasal mask positive pressure artificial respiration therapy is performed. An example to be used will be described. FIG. 3 is a diagram showing an example in which the oxygen concentrator 200 is connected to the ventilator 300, and oxygen supplied from the oxygen concentrator 200 is connected to the mixing unit 400 via the oxygen piping tube 120 and is ventilated. It is a figure which shows an example mixed with the air supplied from the ventilator 300 via the breathing circuit tube 310 by the mixing part 400, and is supplied to a patient. As the ventilator 300, any well-known ventilator is used. be able to. For example, the main body 1100 and the air piping tube 1130 of FIG. 11A can be used as the ventilator 300 and the breathing circuit tube 310 of FIG. As the mixing unit 400, only a combination of a mixing tank and a nasal mask or a nasal mask can be used.

[Example of mixing unit (nasal mask): FIGS. 4 and 5]
FIG. 4 is a diagram illustrating an example of a nasal mask 410 used as the mixing unit 400. The oxygen piping tube 120 and the breathing circuit tube 310 are connected to the nasal mask 410 as shown in the figure, and oxygen supplied from the oxygen concentrator 200 and air supplied from the ventilator 300 are contained in the nasal mask 410. Mixed in. The nasal mask 410 has a sealed structure so that a mixed gas of oxygen and air supplied when the patient's nose is wrapped around the patient's nose does not leak. FIG. 5 is a view showing an example of the nasal mask 410 when a nasal mask corresponding to the present invention is attached to a patient. In addition, when fixing nasal mask 410 to a patient, you may fix using a wearing band.

[Another example of mixing unit: Fig. 6]
FIG. 6 is a diagram illustrating another example of the mixing unit 400 including a mixing tank and a nasal mask, in which oxygen and air are mixed in advance in the mixing tank 440 and then supplied to the patient via the nasal mask 420. Is shown. In FIG. 6, the oxygen piping tube 120 and the breathing circuit tube 310 are connected to the nasal mask 420 by a mixing tank 440, and oxygen supplied from the oxygen concentrator 200 and air supplied from the ventilator 300 are mixed. After being premixed in the tank 440, it is supplied to the nasal mask 420. The example of FIG. 6 shows an example in which the nasal mask 420 is fixed to the patient with the wearing band 430. The nasal mask 420 has a sealed structure so that a mixed gas of oxygen and air supplied when the patient's nose is wrapped around the patient's nose does not leak.

[Operation of ventilator: Fig. 7]
Hereinafter, a method of using the oxygen concentrator 200 according to the present invention when connected to an auxiliary ventilator 300 that promotes ventilation of a patient such as a respiratory failure patient and used in nasal mask positive pressure ventilation will be described. In the following description, a case where the ventilator to which the oxygen concentrator 200 is connected is used in the forced ventilation mode shown in FIG. 7 as an operation mode will be described as an example.

In the forced ventilation mode of FIG. 7, the period between times t1 and t2 is an inspiratory period I in which the patient is forcibly sucked in the oxygen supplied, and the discharge pressure of the ventilator at this time is the IPAP pressure ( (Intake pressure) is set. The period between times t2 and t3 is an expiration period E in which the patient discharges oxygen dioxide and the like, and the discharge pressure of the ventilator at this time is set at the EPAP pressure (expiration pressure). As shown in FIG. 7, the inspiratory pressure and expiratory pressure are set so as to periodically change at an I: E ratio (inhalation period: expiration period time distribution ratio). A predetermined pressure and a predetermined amount of oxygen can be sucked in during the inspiration period, and oxygen dioxide and the like can be discharged outside the body during the expiration period. The period of inhalation period + expiration period is one cycle of breathing (1 beat), and is usually set in the range of 4-30 BPM (beats / minute), and the I: E ratio is set in the range of 1: 1-2. The FIG. 7 shows an example in which I: E = 1: 2, and the IPAP pressure is set 4 cmH ₂₀ higher than the EPAP pressure.

[Setting of ventilator and oxygen concentrator: Fig. 8]
FIG. 8 shows an oxygen concentrator when the oxygen concentrator 200 shown in FIG. 3 is connected to the ventilator 300, the nasal mask 410 of FIG. 4 is used as the mixing unit 400, and the ventilator 300 is used in the forced ventilation mode. An example of the setting of 200 and the ventilator 300 is shown. In the example of FIG. 8, the IPAP pressure of the ventilator 300 is set to 8 to 10 cmH ₂ 0, and the EPAP pressure is set to 4 cmH ₂ 0 lower than the IPAP pressure. Further, an example is shown in which the flow rate of oxygen supplied from the oxygen concentrator 200 to the nasal mask 410 is set to 0.5 L / min and 5 L / min. These set values are determined in advance by the patient's acceptability and the gas value in the blood. Next, the pressure fluctuation shown in FIG. 8 will be described. The pressure fluctuation is an actual measurement value indicating a pressure difference between the pressure (expired air pressure) in the expiration period and the pressure (inspiratory pressure) in the inhalation period measured by the pressure sensor 117 (FIG. 1) of the oxygen concentrator 200. When the concentrator 200, the ventilator 300, and the setting range shown in FIG. 8 are used, the measured pressure fluctuation has a constant value of about 0.30 to 0.32 KPa as shown in FIG. Is shown. An example of the pressure fluctuation measured by the pressure sensor 117 is shown in FIG. 9A.

[Method for monitoring the connection state of the oxygen concentrator: FIGS. 9A and 9B]
Next, when the oxygen concentrator 200 is used while connected to the ventilator 300, the oxygen concentrator 200 uses the pressure fluctuation (see FIG. 9A) measured by the pressure sensor 117 to make the oxygen concentrator 200 use the ventilator 300. It is possible to monitor whether it is securely connected to and used or disconnected. Hereinafter, a method for monitoring the connection state of the oxygen concentrator will be described in detail with reference to FIGS. 9A and 9B.

[When connected normally: FIG. 9A]
First, the case where the oxygen concentrator 200 is normally connected to the mixing unit 400 (nasal mask 410) will be described with reference to FIG. 9A. FIG. 9A shows the pressure P continuously measured by the pressure sensor 117 when the oxygen concentrator 200 is normally connected to the nasal mask 410 and the ventilator 300 operates in the forced ventilation mode shown in FIG. Yes. 9A, the period between t1 and t2 corresponds to the inspiratory period I in FIG. 7, and the maximum pressure measured in this period corresponds to the discharge pressure IPAP pressure of the ventilator in FIG. Further, the period between times t2 and t3 corresponds to the expiration period E of FIG. 7, and the pressure measured in this period corresponds to the discharge pressure EPAP pressure of the ventilator. As described above, when the oxygen concentrator 200 is normally connected to the nasal mask 410, the pressure in the oxygen piping tube 120 connecting the oxygen concentrator 200 to the mixing unit 400 as shown in FIG. It becomes substantially equal to the pressure of the breathing circuit tube 310 connecting the breathing apparatus 300 to the mixing unit 400 (nasal mask 410). Therefore, the pressure detected by the pressure sensor 117 disposed at the upstream position of the humidifier 116 can measure a pressure close to the discharge pressure of the ventilator 300.

  At this time, the pressure difference between the maximum pressure in the inhalation period I and the expiration period E measured by the pressure sensor 117 is 0.3 to 0.32 KPa (almost constant) under the conditions of FIG. Therefore, in the oxygen concentrator 200, as shown in FIG. 9A, the discharge pressure fluctuation monitoring pressure (sometimes referred to as a set pressure) PL is set to PL = EPAP pressure + 0.2 KPa, for example, and the pressure sensor 117 The detected pressure P is always monitored, and if the detected pressure P changes beyond the discharge pressure fluctuation monitoring pressure (set pressure) PL (when P> PL), it is difficult to breathe spontaneously from the ventilator It is determined that the mixed gas (air + oxygen) is forcibly supplied to the patient at a predetermined pressure (IPAP pressure), and the pressure P detected by the pressure sensor 117 exceeds the discharge pressure fluctuation monitoring pressure PL. When there is no change (in the case of P <PL), there is a pressure fluctuation determining means for determining that the mixed gas (air + oxygen) is not supplied from the ventilator to the patient. Therefore, in the case of FIG. 9A, the oxygen concentrator 200 uses this pressure fluctuation determination means, and the mixed gas is kept at a predetermined pressure (IPAP pressure) for a time tI (between time ta and time tb). It is determined that the mixed gas is not supplied during the time tE (from time tb to time tc).

[In case of disconnection: FIG. 9B]
On the other hand, FIG. 9B shows that the oxygen concentrator 200 is connected to the mixing unit 400 (nasal mask 410), and the piping connection tube 121 of the oxygen concentrator 200 is operated for some reason during operation in the forced ventilation mode of the ventilator shown in FIG. Of the pressure measured by the pressure sensor 117 of the oxygen concentrator 200 when it is removed from the mixing unit 400 (nasal mask 410) at time t7 (for example, when the patient accidentally pulls off the oxygen piping tube 120). It is a figure which shows an example. When the oxygen concentrator 200 is removed from the mixing unit 400 (nasal mask 410) at time t7, the pressure measured by the pressure sensor 117 is constant after time t7 as shown in FIG. 9B, and t1 and t2 in FIG. 9B. The pressure change seen in the period between is eliminated. This is because, when the oxygen piping tube 120 of the oxygen concentrator 200 is detached from the nasal mask 410, the pressure sensor 117 measures the pressure of oxygen released into the atmosphere. Unlike always time _t 7 _~td constant pressure (Fig. 9B pressure P when the pipe connection tube 121 (the nasal mask 410) is connected (the pressure P detected by the pressure sensor 117 shown in FIG. 9A) Therefore, the pressure sensor 117 detects the change in the discharge pressure detected when the ventilator 300 is connected (0.32 KPa detected during the time t _{1 to} tm in FIG. 9A). This is because the pressure fluctuation cannot be measured. Therefore, when the pressure detected by the pressure sensor 117 by the pressure fluctuation determination unit described above falls below the set pressure PL, the oxygen concentrator 200 counts the period during which the detected pressure falls below the set pressure. And when the period t measured by the timing unit exceeds a preset set period tL (for example, any period of 5 to 60 seconds, for example, 30 seconds), an abnormal connection state (main oxygen concentration) Connection state determining means for determining that the device 200 has been removed from the ventilator 300). In the case of FIG. 9, the case where the period t from tb to td shown in the figure exceeds the set period tL is shown. Therefore, in the present oxygen concentrator 200, when it is determined by the connection state determination means that the period during which the detected pressure is lower than the set pressure has exceeded the set period tL, it is determined that the oxygen piping tube 120 has been detached from the nasal mask 410. In addition, the alarm unit shown in FIG. 2 has alarm means or alarm light indicating the abnormality to notify the patient or doctor of the abnormality.

  As described above, the oxygen concentrator 200 includes, in addition to the pressure sensor 117 that measures the pressure in the oxygen piping tube 120 as described above, a pressure fluctuation determination unit, a time measurement unit, a connection state determination unit, and a notification unit. Therefore, the oxygen concentrator 200 can constantly monitor the connection state with the ventilator 300. When the oxygen concentrator 200 is disconnected from the ventilator 300, the alarm unit immediately gives an alarm indicating an abnormality. Sounds and warning lights can be emitted to notify doctors and caregivers of abnormalities. Therefore, even when the oxygen concentrator 200 is detached from the ventilator 300, a doctor, a caregiver, or the like can perform a necessary treatment.

[Alarm concentrator alarm control processing: FIG. 10]
FIG. 10 is a flowchart showing an example of the alarm control process of the oxygen concentrator 200 described above. The processing in FIG. 10 is performed by the CPU 401 controlling each unit while using the RAM 403 as a work area based on a control program stored in the ROM 402. Hereinafter, FIG. 10 will be described.

  First, in step S110, the pressure sensor 117 is controlled so as to measure the pressure P in the oxygen piping tube 120. In step S120, the measured pressure P is compared with the set pressure PL (previously stored in the ROM 402) to determine whether or not the discharge pressure varies, and processing according to the determination result is performed. . That is, when the measured pressure P is larger than the set pressure (discharge fluctuation monitoring pressure) PL, the discharge pressure fluctuated (intake was performed, that is, the oxygen piping tube 120 was normally connected. Then, the process proceeds to step S130, where control is performed to reset the no-change time timer that measures the no-change time of the discharge pressure, and then the process returns to step S110.

  On the other hand, in step S120, when the measured pressure P is equal to or lower than the set pressure PL, there is no fluctuation in the discharge pressure (intake is not confirmed, that is, it is not confirmed that the oxygen piping tube 120 is normally connected). The process proceeds to step S140, and it is checked whether or not the no-change time measured by the no-change time timer exceeds a set time tL (for example, 30 seconds).

  In step S140, if the no-change time t measured by the no-change time timer is less than the set time tL (for example, 30 seconds), the process proceeds to step S150, and a predetermined time (Δt) is added to the no-change time timer. Then, the process returns to step S110.

  On the other hand, in step S140, when the no-change time t measured by the no-change time timer exceeds the set time tL, the oxygen piping tube 120 is removed from the mixing part 400 (nasal mask 410) with the ventilator. The process proceeds to step S160, the alarm unit 206 is controlled to generate an alarm sound and / or alarm light, and then the process returns to step S110.

  As described above, the CPU 401 of the oxygen concentrator 200 controls the alarm unit 206 when the oxygen piping tube 120 is disconnected from the mixing unit 400 with the ventilator (disconnected from the nasal mask 410). Alternatively, the alarm light can be generated to notify the abnormality, so that the patient or doctor can immediately perform a treatment such as reconnecting the oxygen piping tube 120 to the mixing unit 400 with the ventilator 300.

  When the oxygen piping tube 120 is attached again to the mixing unit 400 with the ventilator, the pressure P measured in step S110 is larger than the set pressure PL. In step S130, the alarm unit 206 is controlled to stop the alarm sound and / or the alarm light.

As described above, the oxygen concentrator of the present embodiment is used by being connected to a ventilator that forcibly supplies air to a patient having difficulty in spontaneous breathing. And the humidified oxygen from the oxygen concentrator are mixed and supplied. Therefore, a high concentration of oxygen required by the patient can be supplied at a pressure and supply speed suitable for the patient's acceptability and the blood pressure gas value of the patient. In the present oxygen concentrator, a pressure sensor used for detecting the supply pressure of oxygen can be used in combination to constantly monitor the pressure at the connection with the ventilator.
Therefore, when connecting to a ventilator and using it, the pressure of the connection part that is continuously measured is compared with the set pressure, and no pressure fluctuation (inhalation pressure of the ventilator) is detected in the measured pressure It is possible to determine that the oxygen concentrator has been removed from the ventilator for some reason and to notify that it has been disconnected. Therefore, when this oxygen concentrator is used by being connected to a ventilator, it can accurately cope with a situation where the oxygen concentrator is disconnected from the ventilator. Therefore, the oxygen concentrator of this embodiment can be used safely when used in connection with a ventilator.

[Other Embodiments]
In the present invention, a storage medium in which a program code of software that realizes the functions of the embodiments is recorded is provided to a system or apparatus, and a computer (or CPU or MPU) of the system or apparatus is stored in the storage medium. It is also achieved by reading and executing the program code. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention. As a storage medium for supplying such a program code, for example, a floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, nonvolatile memory card, ROM Etc. can be used.

  Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) running on the computer based on the instruction of the program code Includes a case where the function of the above-described embodiment is realized by performing part or all of the actual processing.

  Furthermore, after the program code read from the storage medium is written to the memory provided in the function expansion board inserted into the computer or the function expansion unit connected to the computer, the function is based on the instruction of the program code. This includes the case where the CPU of the expansion board or function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

  Further, the program code of the software that realizes the functions of the above embodiments is distributed via a network, so that it can be stored in a storage means such as a hard disk or memory of a system or apparatus or a storage medium such as a CD-RW or CD-R Needless to say, this can also be achieved by the computer (or CPU or MPU) stored in the system or apparatus reading and executing the program code stored in the storage means or the storage medium.

It is a figure which shows an example of a structure of the oxygen concentrator corresponding to this invention. It is a figure which shows an example of the external appearance of the oxygen concentrator corresponding to this invention. It is a figure which shows an example of the control structure of the oxygen concentrator corresponding to this invention. It is a figure which shows an example which connects the oxygen concentrator corresponding to this invention with a respirator, mixes oxygen and air supplied by a mixing part, and supplies them to a patient. It is a figure which shows an example of the nasal mask corresponding to this invention used as a mixing part which mixes oxygen and air. It is a figure which shows an example which equips a patient with the nasal mask corresponding to this invention. It is a figure which shows the example which equips with a patient the nasal mask of another example corresponding to this invention. It is a figure which shows an example of operation | movement of a ventilator, and is a figure explaining the periodic pressure fluctuation | variation in the operation | movement of the forced ventilation mode which switches an expiration pressure and inhalation pressure periodically. An example of the oxygen concentrator and ventilator settings when the oxygen concentrator corresponding to the present invention is connected to the ventilator and the ventilator is operated in the forced ventilation mode, and the oxygen concentrator pressure sensor in this setting It is a figure which shows an example of the pressure difference of the expiration pressure measured and inhalation pressure. It is a figure which shows an example of the pressure measured by the pressure sensor of the oxygen concentrator corresponding to this invention, when it operates by the forced ventilation mode of the ventilator shown in FIG. It is a figure which shows an example of the pressure measured with the pressure sensor of the oxygen concentrator corresponding to this invention in case the connection tube comes off during operation | movement in the forced ventilation mode of the ventilator shown in FIG. It is a flowchart which shows an example of the alarm control process of the oxygen concentrator corresponding to this invention. It is a figure which shows an example of a respirator. It is a figure which shows an example of the setting mode of a ventilator.

Explanation of symbols

120 oxygen piping tube 200 oxygen concentrator 300 ventilator 310 breathing circuit tube 400 mixing unit 410 nasal mask

Claims (15)

An oxygen concentrator having adjustment means for adjusting the pressure and flow rate of oxygen from an oxygen supply source and supplying the oxygen pressure from an oxygen outlet,
Connecting means for connecting the oxygen outlet and the ventilator to mix the conditioned oxygen with air from the ventilator and to supply the patient;
When the oxygen outlet and the ventilator are connected by the connecting means, pressure detecting means for detecting the pressure in the connecting means;
Monitoring means for monitoring a connection state with the ventilator based on the detected pressure;
Oxygen concentrator characterized by having.   The oxygen concentrator according to claim 1, wherein the connecting means includes a telescopic tube connected to the oxygen outlet. The ventilator has a hermetic mask that is attached to the nostril of the patient and supplies the air to the patient,
The connecting means is connected to the sealed mask of the ventilator so that the adjusted oxygen and the air are mixed in the sealed mask by the telescopic tube. The oxygen concentrator according to claim 2.   The oxygen concentrator according to claim 1, wherein the pressure detection unit is disposed upstream of the oxygen outlet. The monitoring means includes
A pressure fluctuation determination means for comparing the pressure detected by the pressure detection means with a set pressure, and determining that there is no pressure fluctuation when the detected pressure falls below the set pressure;
When it is determined that there is no pressure fluctuation by the pressure fluctuation determining means, time measuring means for timing a period without pressure fluctuation;
A determination unit that determines that the connection state with the ventilator is abnormal when a period of no pressure fluctuation exceeds a predetermined period;
The oxygen concentrator according to claim 1, wherein   The oxygen concentrator according to claim 5, wherein the predetermined period is any value of 5 to 60 seconds.   The oxygen concentrator according to claim 1, further comprising notification means for notifying abnormality of a connection state between the oxygen outlet and the ventilator.   8. The oxygen concentrator according to claim 7, wherein the notifying means notifies the abnormality of the connection state with the ventilator using sound and / or light.   The oxygen concentrator according to claim 1, further comprising a humidifying unit, wherein the oxygen supplied from the oxygen supply source is humidified by the humidifying unit and supplied to the connecting unit as humidified oxygen. Adjusting means for adjusting the pressure and flow rate of oxygen from the oxygen supply source and supplying the oxygen from the oxygen outlet, and for supplying the adjusted oxygen to the patient by mixing with air from the ventilator A connecting means for connecting the outlet portion and the ventilator, and a pressure detecting means for detecting the pressure in the connecting means when the oxygen outlet portion and the ventilator are connected by the connecting means; A control method for an oxygen concentrator having monitoring means for monitoring a connection state with the ventilator based on the detected pressure,
When the oxygen outlet and the ventilator are connected by the connecting means, a pressure detecting step for detecting the pressure in the connecting means;
A monitoring step of monitoring a connection state with the ventilator based on the detected pressure;
Have
The monitoring step includes
A pressure variation determination step of comparing the pressure detected by the pressure detection step with a set pressure, and determining that there is no pressure variation when the detected pressure falls below the set pressure;
When it is determined that there is no pressure variation in the pressure variation determination step, a time measuring step for measuring a period during which there is no pressure variation;
A determination step of determining that the state of connection with the ventilator is abnormal when a period of no pressure fluctuation exceeds a predetermined period;
A control method for an oxygen concentrator characterized by comprising:   The control of the oxygen concentrator according to claim 10, wherein, in the pressure detection step, the pressure in the connection means is detected using a pressure detection means arranged on the upstream side of the oxygen outlet portion. Method.   The method for controlling an oxygen concentrator according to claim 10, wherein the predetermined period is any value of 5 to 60 seconds.   The method for controlling an oxygen concentrator according to claim 10, further comprising a notification step of notifying an abnormality in a connection state between the oxygen outlet and the ventilator. Adjusting means for adjusting the pressure and flow rate of oxygen from the oxygen supply source and supplying the oxygen from the oxygen outlet, and for supplying the adjusted oxygen to the patient by mixing with air from the ventilator A connecting means for connecting the outlet portion and the ventilator, and a pressure detecting means for detecting the pressure in the connecting means when the oxygen outlet portion and the ventilator are connected by the connecting means; A control program for controlling an oxygen concentrator having monitoring means for monitoring a connection state with the ventilator based on the detected pressure,
When the oxygen outlet and the ventilator are connected by the connecting means, a program code for executing a pressure detecting step of detecting a pressure in the connecting means,
Program code for executing a monitoring step of monitoring a connection state with the ventilator based on the detected pressure;
Have
Program code for executing the monitoring step is:
A program code for executing a pressure fluctuation determination step of comparing the pressure detected by the pressure detection step with a set pressure and determining that there is no pressure fluctuation when the detected pressure falls below the set pressure;
When it is determined that there is no pressure fluctuation in the pressure fluctuation determination step, a program code for executing a time measuring step for measuring a period in which there is no pressure fluctuation;
A program code for executing a determination step of determining that the connection state with the ventilator is abnormal when the period without the pressure fluctuation exceeds a predetermined period;
A control program comprising:   A computer-readable storage medium storing the control program according to claim 14.

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