Ventilator and method, system for pressure adjustment thereof

Abstract

This invention discloses a ventilator and its pressure adjustment method and system, which can match various breathing movements in the sleep state and reach the specified target pressure before the end of inhalation, ensuring the user's effectiveness and improving user compliance. This invention adjusts the pressure value in real time according to the human breathing rhythm, improving the comfort of use after sleep and reducing the adverse effects on sleep caused by unsuitable pressure adjustment.

Description

Technical Field

[0001] This invention relates to the field of medical equipment technology, and in particular to a ventilator and its pressure adjustment method and system. Background Technology

[0002] Currently, all pressure regulation logics of continuous positive airway pressure (CPAP) devices on the market are designed based on the pressure switching scheme of bilevel respiratory therapy devices after the expiratory decompression function is turned on. The response speed is very fast, especially when the expiratory decompression level is set to level 3, the pressure change will be very obvious. Some users who are very sensitive to pressure may wake up easily when using the device at night.

[0003] Chinese Patent CN 106267494 B discloses a method for adjusting ventilator parameters based on inspiratory effort and a ventilator in general. The method includes: calculating the rate of change of inspiratory flow from the moment the user begins inspiratory breathing to the moment the ventilator is triggered; calculating the rate of change of inspiratory pressure from the moment the user begins inspiratory breathing to the moment the ventilator is triggered; obtaining the sum of the rates of change of inspiratory flow and inspiratory pressure; obtaining the inspiratory effort level at which the sum of the rates of change is located according to a preset relationship between the flow-pressure rate of change and the inspiratory effort level; and adjusting the ventilator parameters according to the inspiratory effort level at which the sum of the rates of change is located. However, the technical solution disclosed in this patent categorizes inspiratory effort levels by summing the rates of change of flow and pressure, and then adjusts the ventilator parameters accordingly (or manually adjusts the ventilator parameters based on the level categorization). This method cannot truly achieve real-time adjustment of the ventilator parameters (pressure) to suit the user's breathing status during sleep. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a ventilator and its pressure adjustment method and system that adaptively adjusts the matching pressure in real time according to the human body's breathing rhythm (effort level) to address the shortcomings of the prior art.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a pressure adjustment method for a ventilator, comprising the following steps:

[0006] Obtain the expiratory pressure relief level of the sleep apnea machine and convert it into the amount of pressure increase or decrease during inhalation or exhalation (D). p Obtain the output pressure value P of the sleep apnea machine in its current state. e ;

[0007] Obtain the optimal pressure up-adjustment time λ under real-time respiratory conditions s Or the optimal pressure reduction time λ e ;

[0008] If the cumulative inhalation time t aLess than the optimal pressure adjustment time λ s The pressure control value of the sleep apnea machine is then... Otherwise, the pressure control value of the sleep apnea machine is P. e +D p ;or,

[0009] If the exhalation time is accumulated t b Less than the optimal pressure reduction time λ e The pressure control value of the sleep apnea machine is then... Otherwise, the pressure control value of the sleep apnea machine is...

[0010] This invention determines the pressure control value of a sleep apnea machine based on the relationship between the cumulative inhalation / exhalation time and the optimal pressure adjustment / de-adjustment time. This achieves the goal of adjusting the pressure value in real time according to the human breathing rhythm, improving the comfort of use after sleep and reducing the adverse effects on sleep caused by unsuitable pressure adjustment.

[0011] In this invention, the optimal pressure uptime λ s Or the optimal pressure reduction time λ e The calculation formula is:

[0012]

[0013] Among them, R i R is the real-time slope. n T represents the trigger slope / disengagement slope under normal breathing conditions. n The inhalation or exhalation time under normal breathing conditions is n = s or e, and K is the proportion of the pressure that rises to the target pressure under normal breathing conditions.

[0014] In this invention, 0 ≤ K ≤ 1.

[0015] In this invention, the trigger slope / withdrawal slope R under normal breathing conditions n The calculation formula is:

[0016]

[0017] Among them, R i This represents the trigger slope or withdrawal slope for the first N groups under normal breathing conditions. L i This represents the data for the most recent multiple time points after the instantaneous flow velocity reaches above / below the base flow velocity F, updated in real time at time intervals Δt. For all L i The average value, i = 1, 2, ..., I, where I is the number of time points.

[0018] In this invention, to reduce interference from breathing, the trigger slope / withdrawal slope under normal breathing conditions is corrected to obtain the corrected trigger slope / withdrawal slope R. * n With the corrected trigger slope / replacement slope R * n Trigger slope / withdrawal slope as the final normal breathing state:

[0019]

[0020] Among them, R f This represents the trigger slope / removal slope under normal breathing conditions during the last use of the sleep apnea machine.

[0021] In this invention, the inhalation time or exhalation time T under normal breathing conditions n The calculation formula is: t j The time during which the instantaneous flow rate of the N outputs of the sleep apnea machine is above or below the baseline flow rate F when the machine is powered on.

[0022] In this invention, to reduce the impact of abnormal breathing conditions on the calculation accuracy during data acquisition, the inhalation or exhalation time under normal breathing conditions is corrected to obtain the corrected inhalation or exhalation time T. * n The corrected inhalation or exhalation time T * n Inspiratory or expiratory time as a final normal breathing condition: T f This refers to the inspiratory or expiratory time during the last normal breathing condition corresponding to the use of the sleep apnea machine.

[0023] In this invention, the parameters corresponding to the last use of the sleep apnea machine are stored in the memory so as to correct the corresponding data.

[0024] As an inventive concept, the present invention also provides a pressure adjustment system for a sleep apnea machine, including a memory, a processor, and a computer program stored in the memory; the processor executes the computer program to implement the steps of the method described above.

[0025] As an inventive concept, the present invention also provides a sleep apnea machine, characterized in that it employs the pressure adjustment system described above.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention can match various breathing movements in the sleep state, and can reach the specified target pressure before the end of inhalation, ensuring the user's use effect and improving user compliance; the present invention adjusts the pressure value in real time according to the human breathing rhythm, improving the comfort of use after sleep and reducing the adverse effects on sleep caused by unsuitable pressure adjustment. Attached Figure Description

[0027] Figure 1 This is the calculation process for normal inhalation and exhalation time in an embodiment of the present invention;

[0028] Figure 2 This is the instantaneous flow velocity waveform;

[0029] Figure 3 The following is a calculation process for the slope (trigger slope and withdrawal slope) during normal inhalation and exhalation in an embodiment of the present invention;

[0030] Figure 4 This is the slope correction process during normal inhalation and exhalation in an embodiment of the present invention;

[0031] Figure 5 This is the calculation process for the optimal pressure adjustment time and adjustment time in an embodiment of the present invention;

[0032] Figure 6 This is the pressure control value calculation process according to an embodiment of the present invention;

[0033] Figure 7 This is a system structure block diagram according to an embodiment of the present invention;

[0034] Figure 8 This is a functional module diagram for obtaining modules in an embodiment of the present invention;

[0035] Figure 9 This is a functional block diagram of the calculation module in an embodiment of the present invention;

[0036] Figure 10 This is a functional block diagram of the calculation module in an embodiment of the present invention;

[0037] Figure 11 This is a functional diagram of the control module according to an embodiment of the present invention;

[0038] Figure 12 The flow rate curve is shown in the embodiment of the present invention;

[0039] Figure 13 These are flow and pressure change curves under normal and slow breathing conditions according to embodiments of the present invention.

[0040] Figure 14 These are flow and pressure change curves under normal breathing and high-frequency breathing conditions according to embodiments of the present invention.

[0041] Figure 15 This is a comparison chart showing the pressure adjustment under normal breathing conditions and high-frequency breathing conditions. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Example 1

[0044] Embodiment 1 of the present invention provides a pressure adjustment method for a sleep apnea machine, the specific implementation process of which includes:

[0045] I. Calculate the inspiratory time T under normal breathing conditions s and exhalation time T e

[0046] like Figure 1 As shown, taking inhalation time acquisition as an example, the instantaneous flow rate L of N sets of outputs is recorded when the device is powered on and in use. i Above the baseline flow rate F (the baseline flow rate F refers to the gas flow rate leaking from the ventilator mask at the current pressure, which is constant; the instantaneous flow rate in the tubing changes in a waveform during normal breathing), Figure 2 The red dots represent the closest data points after the instantaneous flow velocity reaches the upper part of the base flow velocity F, used to calculate the trigger slope; the green dots represent the closest data points after the instantaneous flow velocity reaches the base flow velocity F, used to calculate the time t for the replacement slope. i .

[0047] The first N sets of intake times t after the equipment starts i Calculate the average, defining the average as the inspiratory time during a user's normal breathing state:

[0048]

[0049] If this is the user's first time using the device, the data is directly retrieved for subsequent calculations and stored in the flash memory. If the device has been used before, the data in the flash memory is stored in the flash memory. f The data is calibrated by averaging, and then the latest data is stored in flash memory to reduce the impact of abnormal breathing conditions on the accuracy of inspiratory time calculation during this data acquisition.

[0050]

[0051] Exhalation time acquisition records the instantaneous flow rate L. i The time at the base flow rate F is calculated in the same way as the inhalation time.

[0052] II. Calculate the trigger slope R under normal breathing conditions. s and the replacement slope R e

[0053] like Figure 3 As shown in (a), taking the acquisition of the triggered slope as an example, the instantaneous flow velocity L is recorded in real time at time intervals Δt. i Data from the five most recent time points after the flow reaches above the baseline velocity F (i*Δt, L) i (i = 1, 2, ..., 5), a trigger slope R within the current normal respiratory cycle is obtained using the least squares method. i :

[0054]

[0055] Record the trigger slope R of the first N groups under normal breathing conditions. i The average value is defined as the trigger slope under normal breathing conditions:

[0056]

[0057] like Figure 4 As shown, the trigger slope obtained this time needs to be averaged with the previous slope stored in the flash to reduce interference from breathing:

[0058]

[0059] Replacement slope R e This refers to the base velocity and instantaneous velocity L. i The slope from above the base flow velocity F to below it is calculated using the same method as the trigger slope, such as... Figure 3 As shown in (b), the instantaneous flow velocity L is recorded and updated in real time at time intervals Δt. i Data from the five most recent time points after reaching the lower bound from below the base velocity F (i*Δt, L) i (i = 1, 2, ..., 5), a turnover slope S within the current normal respiratory cycle is obtained using the least squares method. i Record the substitution slope S of the first N groups under normal breathing conditions. i S is obtained by averaging multiple sets of replacement slopes. s , will S s Compare the slope with the previous slope stored in flash memory to reduce disturbance, and obtain S S校The slope is used as the switching slope under normal breathing conditions and saved to flash memory.

[0060] III. Calculating the optimal pressure up-adjustment time λ under real-time respiratory conditions. s and the time λ reduction e

[0061] like Figure 5 As shown, taking the transition from expiratory to inspiratory phase as an example, the output pressure needs to be K*T. s The pressure is linearly adjusted to the target pressure, where 0 ≤ K ≤ 1. This represents the optimal ratio for increasing pressure to the target pressure under normal breathing conditions. (The ventilator's output pressure needs to be adjusted in real-time according to the user's breathing movements. The K value primarily reflects the most comfortable time for the user to experience when the pressure rises or falls to the target pressure. For example, if the normal inspiratory time is 1.5 seconds, and the device needs to increase the pressure from 6 cmH2O to 9 cmH2O, the user finds it most comfortable when the pressure rises to 9 cmH2O in 0.7 seconds. If it's too fast, the pressure feels too strong; if it's too slow, the pressure feels insufficient. In this case, K = 0.7 / 1.5 = 0.47. The K value is a ratio obtained through clinical user experience.)

[0062] Get the real-time slope R i Compare the real-time slope R i The slope R under normal breathing conditions s To obtain the optimal pressure ramp time, if the current breathing rhythm is slower than the normal breathing rhythm, and the slope Ri in the real-time breathing state is less than the slope Rs in the normal breathing state, then the pressure ramp time in the real-time breathing state is the same as the pressure ramp time in the normal breathing state, which is K*T. s If the current breathing rate is faster than the normal breathing rate, then the slope R of the real-time breathing state... i The slope R is greater than that under normal breathing conditions. s Furthermore, the calculated pressure adjustment time is greater than the fan's response time (the fan can reach the treatment pressure within a specified time). In this case, the time required to adjust the pressure to the target pressure is... Furthermore, this time must be greater than 200ms; if the current breathing rhythm is too fast, causing the pressure regulation time to be less than the fan's response time (the fastest response time for existing fans is 200ms), then... If the equipment cannot adjust to the target pressure within 200ms, then the time required to adjust the pressure to the target pressure should be 200ms, which is the corresponding time for the blower. That is:

[0063]

[0064] The device obtains the optimal boost time λ in real time. sThen, through a linear voltage regulation method, the voltage is adjusted to reach λ in time. s The pressure rises to the specified pressure.

[0065] The down-regulation time during the transition from the inspiratory phase to the expiratory phase was obtained in the same way.

[0066] IV. Calculate the pressure control value at the current time.

[0067] like Figure 6 As shown, taking the transition from the expiratory phase to the inspiratory phase as an example, based on the pressure change D obtained above... p The current output pressure value Pe and the optimal pressure increase time λ of the equipment. s To obtain the target pressure that needs to be controlled in real time and output it to adjust the pressure of the ventilator.

[0068]

[0069] t a This indicates the cumulative time to enter the inspiratory phase.

[0070] Continuous positive airway pressure (CPAP) therapy devices are sleep apnea machines primarily used to treat sleep apnea-hypopnea syndrome. When the expiratory decompression setting is activated, the device reduces its output pressure at the end of expiration, and then restores the pressure to its pre-decompression level upon detecting inhalation. Rapid increases or decreases in pressure can easily wake the user, causing discomfort and reducing compliance. Conversely, if the pressure increase and decrease rates are too slow, and the user's respiratory rate is high, the pressure may not reach the target level before the desired breathing pressure is achieved, especially if the inspiratory pressure is insufficient, thus failing to achieve the desired therapeutic effect and preventing the airway from opening to the ideal state. The method provided in this invention addresses both of these problems simultaneously. It matches various breathing movements during sleep and reaches the target pressure before the end of inhalation, ensuring therapeutic effectiveness and improving user compliance. Furthermore, it adjusts the pressure value in real-time according to the user's breathing rhythm, improving comfort after sleep and reducing the adverse effects on sleep caused by unsuitable pressure adjustments.

[0071] Example 2

[0072] Embodiment 2 of the present invention provides a pressure adjustment system for a sleep apnea machine corresponding to Embodiment 1 above, including a memory, a processor, and a computer program stored in the memory; the processor executes the computer program in the memory to implement the steps of the method in Embodiment 1 above.

[0073] In some implementations, the memory may be high-speed random access memory (RAM), and may also include non-volatile memory, such as at least one disk storage device.

[0074] In other implementations, the processor can be any type of general-purpose processor, such as a central processing unit (CPU) or a digital signal processor (DSP), and no limitation is made here.

[0075] In Example 2, as Figure 7 As shown, the processor includes the following modules: a computing module, a control module, an acquisition module, and a storage module.

[0076] like Figure 8 As shown, the acquisition module is used to acquire device usage time, instantaneous flow rate, stored data, output pressure, basal flow rate, and expiratory pressure relief level.

[0077] like Figure 9 , Figure 10 and Figure 11 As shown, the calculation module is used to calculate the inhalation / exhalation time under normal breathing conditions, the trigger / reversal slope under normal breathing conditions, the trigger / reversal slope under the current breathing conditions, the optimal up / down adjustment time under the current breathing conditions, and the pressure control value of the device at the current time.

[0078] like Figure 12 As shown, the control module controls the speed of the turbine fan (the final feedback of the ventilator pressure adjustment is the speed of the turbine fan; the faster the speed, the higher the pressure, and the slower the speed, the lower the pressure).

[0079] The working process of each module in this embodiment corresponds to the implementation process of Embodiment 1 above, and will not be repeated here.

[0080] Figure 13 The flow rate curve represents a normal respiratory cycle. The horizontal dashed line on the coordinate axis represents the device's baseline flow rate, which is the gas flow rate leaking from the ventilator mask at the current pressure and is constant. The solid waveform curve represents the respiratory flow rate curve formed by sampling the instantaneous flow rate at every Δt interval during normal breathing. The time the flow rate curve is above the baseline flow rate is the time taken for the user to inhale, and the time the flow rate curve is below the baseline flow rate is the time taken for the user to exhale. R represents the trigger slope calculated from the nearest sampling points when the flow rate curve crosses the baseline flow rate.

[0081] Figure 14This is a comparison chart of pressure adjustment under normal and slow breathing conditions. The pressure fluctuations and flow rate waveforms in the chart represent changes during normal breathing. The flow rate curves show that the inspiratory and expiratory times under normal breathing are significantly shorter than those under slow breathing. Furthermore, the slope of the flow rate curve under normal breathing, after crossing the baseline flow rate, is significantly greater than the slope under slow breathing. Therefore, the pressure adjustment time formula for this condition (λ) is... s The first condition in the calculation formula indicates that the time taken for the pressure to adjust from low pressure to high pressure is the same under slow breathing and normal breathing conditions. As can be seen from the pressure curve, the only difference is that the time taken for inhalation is longer than the time taken for exhalation during slow breathing, and the time maintained at high and low pressure will be longer.

[0082] Figure 15 This graph compares pressure adjustment under normal breathing conditions with high-frequency breathing conditions. The solid lines in the pressure and flow rate waveforms correspond to changes during normal breathing. The flow rate curves show that the inspiratory and expiratory times under normal breathing are significantly longer than those under slow breathing. Furthermore, the slope of the flow rate curve under normal breathing, after crossing the baseline flow rate, is significantly less than the slope under slow breathing. Therefore, the pressure adjustment time formula for this state (λ) is... s The second and third conditions in the calculation formula mean that the pressure in high-frequency breathing is adjusted from the same low pressure to the same high pressure than in normal breathing. As can be seen from the pressure change curve, the remaining high and low pressure is related to the exhalation and inhalation time.

[0083] Example 3

[0084] This embodiment provides a sleep apnea machine corresponding to Embodiment 2 above, which adopts the system of Embodiment 2.

[0085] Example 4

[0086] Embodiment 4 of the present invention provides a computer-readable storage medium corresponding to Embodiment 1 above, on which a computer program / instructions are stored. When the computer program / instructions are executed by a processor, they implement the steps of the method of Embodiment 1 above.

[0087] A computer-readable storage medium can be a tangible device that holds and stores instructions for use by an instruction execution device. A computer-readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof.

[0088] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0089] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0091] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0092] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A pressure regulation system for a ventilator, comprising a memory, a processor, and a computer program stored in the memory; characterized in that, The processor executes the computer program to implement the steps of the ventilator pressure adjustment method; the ventilator pressure adjustment method includes the following steps: Obtain the expiratory pressure relief level of the sleep apnea machine and convert it into the amount of pressure increase or decrease during inhalation or exhalation (D). p Obtain the output pressure value P of the sleep apnea machine in its current state. e ; Obtain the optimal pressure up-adjustment time under real-time respiratory conditions Or the optimal time to reduce pressure ; If the inhalation time is accumulated Less than the optimal pressure adjustment time The pressure control value of the sleep apnea machine is then... Otherwise, the pressure control value of the sleep apnea machine is... ;or, If the exhalation time is accumulated Less than the optimal pressure reduction time The pressure control value of the sleep apnea machine is then... Otherwise, the pressure control value of the sleep apnea machine is... .

2. The pressure adjustment system for a ventilator according to claim 1, characterized in that, Optimal time to increase pressure Or the optimal time to reduce pressure The calculation formula is: ； in, For real-time slope, This represents the trigger slope / disengagement slope under normal breathing conditions. The inhalation or exhalation time under normal breathing conditions is n = s or e, and K is the proportion of the pressure that rises to the target pressure under normal breathing conditions.

3. The pressure adjustment system for a ventilator according to claim 2, characterized in that, 。 4. The pressure adjustment system for a ventilator according to claim 2, characterized in that, Trigger slope / withdrawal slope under normal breathing conditions The calculation formula is: ； in, This represents the trigger slope or withdrawal slope for the first N groups under normal breathing conditions. , For time intervals The real-time updated instantaneous flow velocity data at the most recent multiple time points after it has moved from below the base flow velocity F to above / below the base flow velocity. For all The average value, I represents the number of time points.

5. The pressure adjustment system for a ventilator according to claim 4, characterized in that, The trigger slope / withdrawal slope under the normal breathing state is corrected to obtain the corrected trigger slope / withdrawal slope. With the corrected trigger slope / replacement slope Trigger slope / withdrawal slope as the final normal breathing state: ； in, This represents the trigger slope / removal slope under normal breathing conditions during the last use of the sleep apnea machine.

6. The pressure adjustment system for a ventilator according to claim 2, characterized in that, Inspiratory or expiratory time under normal breathing conditions The calculation formula is: ; The time during which the instantaneous flow rate of the N outputs of the sleep apnea machine is above or below the baseline flow rate F when the machine is powered on.

7. The pressure adjustment system for a ventilator according to claim 6, characterized in that, The inspiratory or expiratory time under normal breathing conditions is corrected to obtain the corrected inspiratory or expiratory time. With the corrected inhalation or exhalation time Inspiratory or expiratory time as a final normal breathing condition: ; This refers to the inspiratory or expiratory time during the last normal breathing condition corresponding to the use of the sleep apnea machine.

8. The pressure adjustment system for a ventilator according to claim 5 or 7, characterized in that, The parameters from the last use of the sleep apnea machine are stored in the memory.

9. A ventilator, characterized in that, It employs the pressure adjustment system described in any one of claims 1 to 8.

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