JP2001514941A - Apparatus and method for delivering gas suitable for on-demand additional breathing - Google Patents

Abstract

SUMMARY A device 10 for supplying an on-demand additional breathable gas to a patient receiving a first flow of gas from a first breathable gas supply 10. The device is responsive to receiving a controllable gas source 118 that communicates a selective fluid to the patient and an input signal indicating that the first gas supply 10 cannot meet the patient's inspiratory requirements. And control means 122 suitable for activating the controllable gas source. The method includes monitoring a respirable gas supply 10 and activating a controllable gas source 118 when the monitoring indicates that the first gas supply 10 cannot meet a patient's inspiratory demand. And causing it to occur.

Description

DETAILED DESCRIPTION OF THE INVENTION

TECHNICAL FIELD [0001] The present invention relates to an apparatus and method for providing on demand an additional breathable gas to a patient receiving a first flow of breathable gas from a first breathable gas supply. .

The invention basically applies to gas supply devices designed, for example, for continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) and Obstructive respiratory illness (COPD), cystic fibrosis, emphysema, and various other neurological conditions that require higher gas flow rates than typically provided by CPAP gas delivery systems It applies to gas supply devices designed to be suitable for the treatment of other diseases and disorders, or other syndromes and diseases, such as other diseases of the respiratory system.

BACKGROUND OF THE INVENTION [0003] The treatment of OSA with a CPAP gas supply involves the use of air (or other breathable gas) pressurized above atmospheric pressure, typically through a conduit and a nasal and / or mouth mask. With persistent distribution to the patient's respiratory tract. The pressure of the gas delivered to the patient can be a constant level, a binary level (synchronized with the patient's expiration and inspiration), or the level can be set automatically.

FIG. 1 illustrates a conduit 14 and nasal mask 16 used, for example, in CPAP treatment.
1 schematically shows a device 10 according to the prior art for supplying breathable gas to a patient 12 via. Apparatus 10 includes a flow generator 18 in the form of a motor and fan assembly, the power of which is supplied by drive means 20 that becomes common from a brushless motor control circuit that drives a power transistor connected to the motor windings. You. The drive means 20 is controlled by electronic or computer control means 22. The control means 22 variously changes the motor speed to control the pressure of the gas to be distributed. Alternatively, the control means 22 may adjust the solenoid driver to adjust the gas pressure by allowing excess gas to flow out through a solenoid control relief valve. The control means 22 can be programmed by the physician to dispense in a predetermined series of pressure patterns or in one pattern, depending on the patient's breathing pattern and the required treatment as described above.

[0005] Such prior art devices include a flow generator designed for CPAP treatment,
For example, COPD, since a maximum flow of 100 l / min or less, which would not completely satisfy the impulse demand of the impulsive inspiration of a patient with COPD, without causing a significant drop in treatment pressure, for example, May not be appropriate for the treatment of patients with

[0006] In addition, patients with COPD have a very fast inspiratory time compared to "normal" breathing, which is often accompanied by a significant increase in the maximum inspiratory flow. Conventional CPAP flow generators cannot cope with this sharp increase in flow demand, and consequently, when patients require gas at high pressures,
The pressure in the air distribution system will drop.

[0007] Producing a flow generator with sufficient sustained flow capacity to meet the required breathing of COPD patients is generally uneconomic for a smaller market size than for OSA patients.

It is an object of the present invention to substantially overcome, or at least ameliorate, these deficiencies in the prior art.

DISCLOSURE OF THE INVENTION [0009] The present invention, therefore, in its first form, receives a first flow of breathable gas from a first source of breathable gas. Disclosed is an apparatus for providing an additional respirable gas to a patient on demand, the apparatus comprising a second source of respirable gas controllable with selective gas flow to and from the patient. Control means adapted to activate said controllable second breathable gas source in response to receiving an input signal indicating that said first gas supply is not able to meet a patient's inspiratory request; It has.

[0010] In a second aspect, the present invention discloses an apparatus for delivering breathable gas to a patient, the apparatus comprising a first breathable gas source in gaseous communication with the patient, A second source of breathable gas that is controllable with gas selectively flowing to and from the patient; and an input signal indicating that the first gas supply is unable to meet a patient's inspiratory demand. Control means responsive to the reception for activating the controllable second breathable gas source.

[0011] The breathable gas is preferably air.

[0012] The first breathable gas source preferably includes a flow generator in the form of a fan driven by an electric motor.

The controllable second breathable gas source is preferably a flow generator in the form of a fan driven by an electric motor, a pressurized gas storage chamber, a connection to a constant pressure gas source, or a positive displacement gas source. Device or one of a combination thereof.

[0014] The positive displacement device is preferably a diaphragm that substantially seals the chamber with gas flowing to and from the patient, the diaphragm being electromagnetic to supply gas within the chamber to the patient. It moves through the chamber in response to an actuator.

In one embodiment, the control means input signal is a signal indicating that the first flow generator has reached a maximum output.

In another embodiment, the control means input signal is such that the pressure of the gas supplied to the patient is:
This is a signal indicating that the voltage has dropped below a predetermined minimum level. In this embodiment, the controllable or second gas supply does not receive a control signal from the first gas supply, for example, from a pressure transducer or in a patient gas supply conduit or mask. Received from other devices that measure the pressure.

In yet another embodiment, the control means input signal is a signal indicating the start of inspiration of the patient, as indicated by a sudden increase in the flow rate of air supplied to the patient.

[0018] In a third aspect, the present invention discloses a plurality of breathable gas supply devices in gaseous communication with a common patient.

The gas supply devices are preferably connected in parallel.

In a fourth aspect, the present invention discloses a method for providing additional breathable gas on demand to a patient undergoing a first flow of breathable gas. The method comprises the steps of: monitoring a first flow of breathable gas delivered to a patient; and when the monitoring indicates that the first gas supply cannot meet a patient's inspiratory demand, Activating a controllable second breathable gas source that selectively communicates fluid to the patient.

In a fifth aspect, the present invention discloses a method for delivering breathable gas to a patient. The method comprises: providing a first flow of breathable gas to a patient; monitoring a first flow of gas delivered to the patient; Activating a second controllable breathable gas source that selectively communicates fluid to the patient when indicating that the request cannot be met.

In one example, the second breathable gas source is activated when the monitoring step indicates that the supply of the first breathable gas is at maximum output.

In another example, the second breathable gas source is activated when the monitoring step indicates that the pressure of the first breathable gas source is less than a predetermined minimum level. In this example, the pressure of the first gas source is preferably measured at a mask worn on the patient or at a gas supply line connecting the mask to the first breathable gas source.

FIG. 2 shows a first embodiment of an apparatus for supplying additional breathable gas on demand, similar to that shown in FIG. Shown in the form of a second breathable gas supply system 110 for use in connection with a first traditional breathable gas supply device 10. The second breathable gas supply 110 comprises a flow generator 118 powered by a drive means 120 under the control of a control means 122 incorporated in the gas supply 10. The output of the second flow generator 118 is directed from the tube branch 114 into the gas supply tube 14 of the patient. When the control means 122 detects that the flow generator 18 is unable to meet the patient's inspiratory demand, for example, by detecting a decrease in pressure of the supplied gas when the gas pressure is expected to increase. , A signal is sent to the drive means 120 to energize the flow generator 118, thereby providing an almost instantaneous additional flow of gas to the patient 12 (not shown). Similarly, when the control means 122 detects that additional gas is no longer required, it does not energize the gas flow generator 18.

This embodiment allows treatment of patients whose inspiratory demands exceed conventional CPAP flow generators to be accommodated by the addition of simple, low cost motor, fan, and driver assemblies to conventional devices. .

In another embodiment (not shown), the gas from the first flow generator 18 (rather than the patient) is supplied to the second flow generator 18 when the second flow generator 118 does not supply gas. To stop pushing into 118, one-way valve is connected to tube branch 11
4

FIG. 3 shows a second gas supply device 210 including a flow generator 218 that is constantly energized by the drive means 220. In its simplest form, fluid communication between flow generator 218 and tube branch 214 is controlled by control means 22.
2 is selectively blocked by a valve 226 controlled by 2. As in the first embodiment, when the control means 222 detects that it is not meeting the patient's inspiratory demand, it opens the valve 226 and additional gas is supplied from the branch pipe 214 to the main pipe 14 and to the patient. To allow. Similarly, the control means 222 closes the valve 226 upon detecting that it has met the patient's inspiratory needs.

In another form of this embodiment, an air receiver 228 is inserted between the flow generator 218 and the valve 226, as shown. The receiver 228 is continuously pressurized by the flow generator 218 and the control means 222
Opening a large volume of high pressure gas can be supplied to meet the patient's instantaneous inspiratory demands.

In a further variation (not shown), the flow generator 218 and the drive means 220 are replaced by a high pressure oxygen or compressed air supply from an external source, for example a compressed gas storage tank or a hospital internal gas source, Optionally, the valve 22
6 or directly to the receiver 228.

The third embodiment shown in FIG. 4 essentially comprises a main respiratory gas supply 10 in the form of the conventional CPAP gas supply 10 shown in FIG. A second CPAP gas supply device 310 connected to the gas supply pipe 14. In this embodiment, the control unit 322b of the second device 310 receives a control signal from the control unit 322a of the main device 10. As in the previous embodiment, when it is detected that the patient's inspiratory demand is not met, the control means 322a sends a signal to the control means 322b, which causes the second drive means 320 to Activate the two-flow generator 318. As a result, additional gas flow flows through branch 314 to main tube 14 and to patient 12.

In the third embodiment, since the second control means 322b is connected to the first control means 322a, the second gas supply device automatically operates as a dependent device.

In the fourth embodiment shown in FIG. 5, the second gas supply device 410 receives a signal from a control unit 422 having a differential pressure transducer. The differential pressure transducer receives pressure instructions from both sides of the flow restrictor 430 via the tube 432. When the transducer detects that the pressure in the gas supply line 14 to the patient has fallen below a predetermined minimum level, the control means 422 activates the drive means 420 to activate the flow generator.
Activate 418. As a result, additional gas is supplied. The control means 422 is programmed to provide additional gas flow when the pressure drop in the flow restriction 430 drops below, for example, about 0.5 cm of water. As described above, the flow generator 418 is stopped when the transducer of the control system 422 indicates that the pressure in the gas supply line 14 has exceeded this level, or after a predetermined time has elapsed.

In a variant (not shown) of the fourth embodiment, the pressure in the patient's mask 16 is measured via a pressure line connected thereto. In this modification, means for measuring the flow rate in the gas supply pipe 14 to the patient becomes unnecessary.

In the fifth embodiment shown in FIG. 6, the second gas supply device 510 includes a chamber 540, a diaphragm 542, and an electromagnetic actuator 544. The second gas supply 510 is present, such as a loudspeaker located within the enclosure. The chamber 540 is fluidly connected via branch 514 to the gas supply line 14 to the patient.

Also in this embodiment, control means 522 using a differential pressure transducer 520 connected by tubes 532 on both sides of the flow restricting section 530 is employed.

When the transducer 520 detects a sudden drop in the supply of gas to the patient, the control means 522 activates the electromagnetic actuator 544, thereby activating the diaphragm 542 provided across the chamber 540. . As a result, the volume of air 546 indicated by oblique lines is forcibly sent into the gas supply pipe 14 to supplement the supply of the main gas from the main flow generator 10.

In this embodiment, a flow restrictor 548 is provided to prevent additional gas from flowing into the main flow generator 10 on behalf of the patient. One-way valves can be employed for this purpose.

The effect of the additional gas is best seen in FIGS. 7a to 7e. 7a to 7e show the air flow rate 600 to the patient, the respiration detection 610, the output pressure 620 from the main flow generator, and the second flow between the inspiration time (Ti) and the expiration time (Te), respectively. 7 is a plot of the output pressure 630 from the generator and the combined output pressure 640.

The line 600 indicates that the flow rate to the patient (F) changes from negative to positive at the start of inspiration (Ti) or vice versa (Te). ing.

Line 610 indicates that the output of the pressure transducer is high for Ti indicating inspiration and low for Te indicating expiration.

Line 620 indicates that the fan is rapidly driven between no flow at 621 and maximum flow at 622, resulting in an increase in pressure (P) of main gas supply 10 to a maximum flow. Is shown.

A line 630 indicates the pressure of the second gas supply device after the start-up at time Ti and after the shutdown at time Te.

A line 640 indicates the sum of the line 620 and the line 630. This shows how quickly the fifth embodiment reaches the maximum pressure and satisfies the patient's inspiratory demand compared to the case of the fan alone indicated by line 620 in FIG. 7c.

The opposite occurs at the exhalation time (Te). That is, the output pressure is rapidly decreasing as the diaphragm is retracted to facilitate exhalation of the patient.

An advantage of the embodiments of the invention described above is that additional gas supplies can be used together with minimal modifications to the first or main gas supply. This is especially true in the fifth embodiment, which is operatively connected to the gas supply tube or mask to the patient, but not to the main gas supply.

The main gas supply may be a conventional CPAP gas supply, which is widely used, so that inventory can be reduced.

Further, the additional flow generator is not limited to a CPAP flow generator manufactured by the same company that manufactured the main flow generator, but may be used together with CPAP flow generators manufactured by various companies. it can.

Although the invention has been described with reference to specific embodiments, those skilled in the art will appreciate that the invention may be embodied in other forms.

For example, it can be appreciated that the present invention is not limited to only the first and second gas supply devices. If the supply by the first supply device is insufficient, the multi-gas supply device can be connected according to the invention to a control system which activates all other flow generators. Further, for example, when it is detected that the gas supplied by the already activated flow generator is insufficient, the additional flow generators may be sequentially activated.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a prior art CPAP breathable gas supply.

FIG. 2 is a schematic diagram of a first embodiment of a device for supplying additional breathable gas on demand.

FIG. 3 is a schematic side view of a second embodiment of the device for supplying additional breathable gas on demand.

FIG. 4 is a schematic view of a third embodiment of an apparatus for supplying additional breathable gas on demand.

FIG. 5 is a schematic view of a fourth embodiment of an apparatus for supplying additional breathable gas on demand.

FIG. 6 is a schematic view of a fifth embodiment of an apparatus for supplying additional breathable gas on demand.

FIG. 7a shows a schematic plot of patient airflow between inspiration and expiration.

FIG. 7b shows a schematic plot of respiration detection.

FIG. 7c shows a schematic plot of the output pressure of the first flow generator.

FIG. 7d shows a schematic plot of the output pressure of the second flow generation.

FIG. 7e shows a schematic plot of the output pressure of the combined flow generator.

[Explanation of symbols]

 Reference Signs List 10 gas supply device 18 first flow generator 110 second respiratory gas supply device 114 pipe branch 118 second flow generator 120 drive means 122 control means 214 pipe branch 218 flow generator 220 drive means 222 control means 226 valve 228 air receiver

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, GM, HR, HU, ID, IL, IS, JP, KE, KG, KP , KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZW (72) Inventor Peter John Deacon Wickham Australia 2046 New South Wales Five Dock, 20 Hampden Road

Claims (22)

[Claims] 1. A device for delivering an on-demand additional breathable gas to a patient receiving a first flow of gas from a first breathable gas supply, the device comprising: In response to receiving an input signal indicating that the first gas supply cannot meet a patient's inspiratory demand, And control means suitable for activating the two respirable gas sources. 2. An apparatus for delivering a breathable gas to a patient, the apparatus comprising: a first breathable gas source that communicates fluid to a patient's trachea; and a first gas. A controllable second breathable gas source that selectively communicates fluid to the patient's trachea in response to receiving an input signal indicating that the supply cannot meet the patient's inspiratory demands. An apparatus, comprising: 3. The gas suitable for breathing is air.
Or the device according to 2. 4. The device according to claim 1, wherein the first respirable gas supply comprises a fan-shaped flow generator driven by an electric motor. 5. The controllable second breathable gas source is a fan-shaped flow generator driven by an electric motor, a pressure regulated gas storage chamber, and a constant pressure regulated gas source. Apparatus according to any of the preceding claims, characterized in that it comprises a connection, a positive displacement device, or a combination thereof. 6. The positive displacement device is a diaphragm that substantially seals a chamber that communicates fluid to a patient's trachea, wherein the diaphragm is responsive to an electromagnetic actuator to supply gas within the chamber to the patient. The device according to claim 5, characterized in that it moves through the chamber. 7. The apparatus according to claim 1, further comprising an adjustable valve after the pressure-regulated gas storage chamber, said valve being adapted to open in response to said control means receiving said input signal. Item 6. The apparatus according to Item 5. 8. Apparatus according to claim 1, wherein the input signal control means is a signal indicative of a first flow generator reaching a maximum output. 9. The method according to claim 1, wherein the control means for the input signal is a signal indicating a gas pressure supplied to the patient below a predetermined minimum level. Equipment. 10. The adjustable gas source receives an adjustment signal from a pressure transducer or other device that measures pressure at a gas supply conduit or mask of a patient. The described device. 11. The device according to claim 1, wherein the control means for the input signal is a signal indicating the start of inspiration of the patient. 12. The apparatus according to claim 11, wherein the onset of inspiration is indicated by a sudden increase in the flow rate of the air supplied to the patient. 13. The one-way valve according to claim 1, further comprising a one-way valve in the flow path between the controllable second breathable gas source and the patient. apparatus. 14. A multi-breathable gas supply that delivers fluid to a common patient. 15. The gas supply device is connected in parallel,
15. The multiple breathable gas supply device of claim 14. 16. The multiple respirable gas supply device according to claim 14, wherein the gas supply device is under common control. 17. A method for delivering an on-demand additional breathable gas to a patient receiving a first flow of breathable gas, the method comprising the steps of: Monitoring a first flow of gas; and a controllable second fluid that selectively communicates fluid to the patient when monitoring indicates that the first gas supply cannot meet the patient's inspiratory demands. Activating two breathable gas sources. 18. A method for delivering a breathable gas to a patient, the method comprising:
The method includes providing a first flow of breathable gas to a patient, monitoring the first flow of gas delivered to the patient, wherein the first gas supply responds to the patient's inspiratory demands. Activating a controllable second respirable gas source that selectively communicates fluid to the patient when the monitoring indicates that a match cannot be made. 19. The second respirable gas source is activated when the monitoring step indicates that the first respirable gas supply is at full power. 19. The method according to 18. 20. The second breathable gas source is activated when the monitoring step indicates that the pressure of the first breathable gas supply is below a predetermined minimum level. The method according to claim 17 or 18, wherein 21. The pressure of the first gas supply is measured at a mask worn by the patient or at a gas supply conduit connecting the mask to a first breathable gas supply. Item 21. The method according to Item 20, 22. The method according to claim 17, wherein the second respirable gas source is activated when the monitoring step indicates that the patient's inspiration has begun.