PEEP Valve Control Transition Regulation Method, Device and Ventilator during Inspiration and Expiration Phases

Abstract

The present invention belongs to the technical field of ventilators, and in particular relates to a method, device, and ventilator for controlling the transition adjustment of a PEEP valve during the inhalation and exhalation phases. The method comprises: when the ventilator switches from the inhalation phase to the exhalation phase, controlling the control amount of the PEEP valve to adjust from the inhalation phase control amount to the exhalation phase control amount according to a preset switching time and transition curve; when the ventilator switches from the exhalation phase to the inhalation phase, controlling the control amount of the PEEP valve to adjust from the exhalation phase control amount to the inhalation phase control amount according to a preset switching time and transition curve. Using the method of the present invention, the PEEP valve can be continuously controlled without step changes during the ventilator phase switching, thus overcoming the patient's discomfort caused by airflow tremors in the pipeline and improving the quality of the ventilator.

Description

Technical Field

[0001] The present invention belongs to the technical field of ventilators, and in particular relates to a method and device for controlling transition adjustment of a PEEP valve during inspiration and expiration phases, and a ventilator. Background Art

[0002] A ventilator is a device that replaces, controls, or modifies normal physiological breathing, increasing lung ventilation, improving respiratory function, reducing work of breathing, and conserving cardiac reserve. It is an indispensable medical device for treating patients with respiratory failure. Modern ventilators primarily utilize positive pressure ventilation (CPAV), which offers a variety of ventilation modes to suit different patient populations and specific respiratory conditions. A single ventilator breath consists of an inspiratory phase and an expiratory phase. While the control of PEEP (Positive End Expiratory Pressure) during these two phases has been extensively described, such as PID control and adaptive control, the control of the PEEP valve during phase switching is rarely discussed. Control of the PEEP valve is crucial throughout the entire ventilator ventilation cycle. During the inspiratory phase, the PEEP valve must be closed to ensure airflow into the lungs; during the expiratory phase, the PEEP valve must be controlled to maintain a certain pressure in the airway at the end of expiration to prevent alveolar collapse. However, if the PEEP valve is not properly controlled during the inspiratory-expiratory phase transition, the airflow in the pipeline will vibrate, causing discomfort to the patient and directly affecting the quality of the ventilator. In order to ensure that the system responds quickly and tracks the given desired pressure without overshoot, it is necessary to increase the control transition process during the phase transition. Summary of the Invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and propose a method, device and ventilator for controlling the transition adjustment of a PEEP valve during the inspiration and expiration phases.

[0004] To achieve the above objectives, the present invention proposes a method for controlling transition of a PEEP valve during inspiration and expiration, the method comprising:

[0005] When the ventilator switches from the inspiratory phase to the expiratory phase, the control amount of the PEEP valve is adjusted from the inspiratory phase control amount to the expiratory phase control amount according to the preset switching time and transition curve;

[0006] When the ventilator switches from the expiratory phase to the inspiratory phase, the control amount of the PEEP valve is adjusted from the expiratory phase control amount to the inspiratory phase control amount according to the preset switching time and transition curve.

[0007] As an improvement to the above method, when the ventilator switches from the inspiratory phase to the expiratory phase, the switching time is 50ms to 200ms; when the ventilator switches from the expiratory phase to the inspiratory phase, the switching time is 50ms to 100ms.

[0008] As an improvement to the above method, the transition curve is an exponential curve, a straight line or an S-shaped curve.

[0009] As an improvement to the above method, when the ventilator switches from the inspiratory phase to the expiratory phase, when the transition curve is an exponential curve, the following formula is satisfied:

[0010] CP(t)=CP1+(CP2-CP1)×(1-e -t×4 / CT )t∈(0,CT)

[0011] When the transition curve is a straight line, it satisfies the following formula:

[0012] CP(t)=CP1+(CP2-CP1)×t / CT t∈(0,CT)

[0013] When the transition curve CP(t) is an S-shaped curve, it satisfies the following equation:

[0014]

[0015] Where CP(t) represents the specific PEEP valve control amount, t represents the time when the relative adjustment starts, CP1 and CP2 represent the inspiratory and expiratory control amounts when switching from the inspiratory phase to the expiratory phase, respectively, and CT represents the switching time.

[0016] As an improvement to the above method, when the ventilator switches from the expiratory phase to the inspiratory phase, when the transition curve is an exponential curve, the following formula is satisfied:

[0017] CP(t)=CP3+(CP4-CP3)×(1-e -t×4 / CT )t∈(0,CT)

[0018] When the transition curve is a straight line, it satisfies the following formula:

[0019] CP(t)=CP3+(CP4-CP3)×t / CT t∈(0,CT)

[0020] When the transition curve is an S-shaped curve, it satisfies the following formula:

[0021]

[0022] Where CP(t) represents the specific PEEP valve control amount, t represents the time when the relative adjustment starts, CP3 and CP4 represent the inspiratory phase control amount and the expiratory phase control amount when switching from the expiratory phase to the inspiratory phase, respectively, and CT represents the switching time.

[0023] On the other hand, the present invention provides a PEEP valve transition adjustment device for controlling the inspiratory and expiratory phases, the device comprising:

[0024] The inspiratory phase to expiratory phase adjustment module is used to control the PEEP valve to adjust the control amount from the inspiratory phase control amount to the expiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the inspiratory phase to the expiratory phase;

[0025] The expiratory phase to inspiratory phase adjustment module is used to control the control amount of the PEEP valve from the expiratory phase control amount to the inspiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the expiratory phase to the inspiratory phase.

[0026] In a third aspect, the present invention further provides a ventilator comprising a PEEP valve for controlling a transition adjustment device during inspiration and expiration, wherein the device comprises:

[0027] The inspiratory phase to expiratory phase adjustment module is used to control the PEEP valve to adjust the control amount from the inspiratory phase control amount to the expiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the inspiratory phase to the expiratory phase;

[0028] The expiratory phase to inspiratory phase adjustment module is used to control the control amount of the PEEP valve from the expiratory phase control amount to the inspiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the expiratory phase to the inspiratory phase.

[0029] Compared with the prior art, the advantages of the present invention are:

[0030] 1. The PEEP valve control algorithm of the present invention during the switching of the inspiratory and expiratory phases can achieve continuous control of the PEEP valve without stepping, thus solving the problem of airflow tremor during switching;

[0031] 2. The present invention proposes that PEEP excess during respiratory phase switching can be controlled according to an exponential, linear, or S-shaped curve, and proposes a PEEP valve to control the transition time during respiratory phase switching;

[0032] 3. The method of the present invention has been implemented on a ventilator and has achieved good technical results. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of PEEP valve control during the transition from inspiration to expiration;

[0034] Figure 2 This is a schematic diagram of PEEP valve control when the expiratory phase transitions to the inspiratory phase. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0036] Example 1

[0037] Embodiment 1 of the present invention proposes a method for controlling transition adjustment of a PEEP valve during inspiration and expiration phases.

[0038] Ventilator ventilation is divided into inspiratory phase and expiratory phase, and the corresponding phase switching is: inspiratory phase to expiratory phase, and expiratory phase to inspiratory phase.

[0039] 1. Inspiratory phase to expiratory phase:

[0040] If the PEEP valve's control level is CP1 during inspiration and CP2 during expiration, a direct jump from CP1 to CP2 during the inspiratory-expiratory phase transition can significantly impact the airflow in the circuit, causing airflow oscillation. This problem can be addressed by adding a transition step during the phase transition, using an algorithm to gradually change the PEEP valve control level from P1 to P2. The transition time, CT, is typically 50 to 200 ms. For rapid response and the elimination of oscillation, the transition curve can typically be an exponential, linear, or S-shaped curve. The exponential curve has the fastest response, followed by the linear curve, while the S-shaped curve has the slowest response. The timing and curve for the transition can be selected based on actual system testing results; the most important thing is that no step changes occur. These three curves essentially cover the basic control curves. The key to selecting the right one is to ensure a smooth transition of PEEP valve control and avoid airflow oscillations that could impact patient comfort.

[0041] The trajectory of the inspiratory phase to expiratory phase index curve is:

[0042] CP(t)=CP2+(CP1-CP2)×(e -t×4 / CT )t∈(0,CT)

[0043] The linear PEEP control trajectory is:

[0044] CP(t)=CP1-(CP1-CP2)×t / CT t∈(0,CT)

[0045] The S-shaped PEEP control trajectory is:

[0046] CP(t)=CP1-3×(CP1-CP2)×t 2 / CT 2 +2×(CP1-CP2)×t 3 / CT 3 t∈(0,CT)

[0047] In the above equations, t represents the transition time from inspiration to expiration, and t is reset to zero at the beginning of each expiration. CP(t) represents the specific PEEP control value, CP1 represents the PEEP valve control value during inspiration, CP2 represents the PEEP valve control value during expiration, and CT represents the total switching time.

[0048] 2. Expiratory phase to inspiratory phase:

[0049] During the transition from the respiratory phase to the inspiratory phase, there is also the problem of a jump in the PEEP valve control amount. The instantaneous closure of the PEEP valve will cause airflow vibration, and a transition link needs to be added. If the PEEP valve control amount in the expiratory phase is CP1, the PEEP valve control amount in the inspiratory phase is CP2. The switching time CT from the expiratory phase to the inspiratory phase should not be too long. If it is too long, the flow rate will not increase at the beginning of inspiration. If it is too short, the desired effect will not be achieved. It is generally 50ms to 100ms, mainly considering the system response time. The response time of ventilators currently on the market is within 100ms.

[0050] Similarly, the transition curve can be an exponential curve, a straight line, an S-shaped curve, etc. Of course, the transition time and curve can be selected according to the actual system, and the most important thing is that no step occurs.

[0051] The trajectory of the exhalation phase to inhalation phase index curve is:

[0052] CP(t)=CP3+(CP4-CP3)×(1-e -t×4 / CT )t∈(0,CT)

[0053] The linear PEEP control trajectory is:

[0054] CP(t)=CP3+(CP4-CP3)×t / CT t∈(0,CT)

[0055] The S-shaped PEEP control trajectory is:

[0056]

[0057] In the above equations, t represents the switching time from exhalation to inspiration, and t is reset to zero at the beginning of each inspiration. CP(t) represents the specific PEEP control value, CP3 represents the PEEP valve control value during the expiratory to inspiratory phase, CP4 represents the PEEP valve control value during the inspiratory to expiratory phase, and CT represents the total switching time.

[0058] Example 2

[0059] Example 2 of the present invention provides a PEEP valve transition adjustment device for controlling the inspiratory and expiratory phases, using the same method as Example 1. The device includes:

[0060] The inspiratory phase to expiratory phase adjustment module is used to control the PEEP valve to adjust the control amount from the inspiratory phase control amount to the expiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the inspiratory phase to the expiratory phase;

[0061] The expiratory phase to inspiratory phase adjustment module is used to control the control amount of the PEEP valve from the expiratory phase control amount to the inspiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the expiratory phase to the inspiratory phase.

[0062] Example 3

[0063] Embodiment 3 of the present invention provides a ventilator comprising the PEEP valve of embodiment 2 for controlling the transition adjustment device during the inspiration and expiration phases. The specific processing method will not be described in detail.

[0064] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention and are intended to be encompassed by the claims of the present invention.

Claims

1. A PEEP valve in the inspiration and expiration phase control transition adjustment device, characterized in that: The device comprises: The inspiratory phase to expiratory phase adjustment module is used to control the PEEP valve to adjust the control amount from the inspiratory phase control amount to the expiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the inspiratory phase to the expiratory phase; The expiratory phase to inspiratory phase adjustment module is used to control the PEEP valve to adjust the control amount from the expiratory phase control amount to the inspiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the expiratory phase to the inspiratory phase; When the ventilator switches from the inspiratory phase to the expiratory phase, the switching time is 50ms to 200ms; when the ventilator switches from the expiratory phase to the inspiratory phase, the switching time is 50ms to 100ms; The transition curve is an exponential curve, a straight line or an S-shaped curve; When the ventilator switches from the inspiratory phase to the expiratory phase, when the transition curve is an exponential curve, it satisfies the following formula: CP(t)=CP1+(CP2-CP1)×(1-e -t×4 / CT ) t∈(0,CT) When the transition curve is a straight line, it satisfies the following formula: CP(t)=CP1+(CP2-CP1)×t / CT t∈(0,CT) When the transition curve CP(t) is an S-shaped curve, it satisfies the following equation: Where CP(t) represents the specific PEEP valve control amount, t represents the time when the relative adjustment starts, CP1 and CP2 are the inspiratory phase control amount and expiratory phase control amount when switching from the inspiratory phase to the expiratory phase, respectively, and CT is the switching time; When the ventilator switches from the expiratory phase to the inspiratory phase, when the transition curve is an exponential curve, it satisfies the following formula: CP(t)=CP3+(CP4-CP3)×(1-e -t×4 / CT ) t∈(0,CT) When the transition curve is a straight line, it satisfies the following formula: CP(t)=CP3+(CP4-CP3)×t / CT t∈(0,CT) When the transition curve is an S-shaped curve, it satisfies the following formula: Where CP(t) represents the specific PEEP valve control amount, t represents the time when the relative adjustment starts, CP3 and CP4 represent the inspiratory phase control amount and the expiratory phase control amount when switching from the expiratory phase to the inspiratory phase, respectively, and CT represents the switching time.

2. A ventilator comprising a PEEP valve for controlling the transition between inspiration and expiration, characterized in that: The device comprises: The inspiratory phase to expiratory phase adjustment module is used to control the PEEP valve to adjust the control amount from the inspiratory phase control amount to the expiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the inspiratory phase to the expiratory phase; The expiratory phase to inspiratory phase adjustment module is used to control the PEEP valve to adjust the control amount from the expiratory phase control amount to the inspiratory phase control amount according to the preset switching time and transition curve when the ventilator switches from the expiratory phase to the inspiratory phase; When the ventilator switches from the inspiratory phase to the expiratory phase, the switching time is 50ms to 200ms; when the ventilator switches from the expiratory phase to the inspiratory phase, the switching time is 50ms to 100ms; The transition curve is an exponential curve, a straight line or an S-shaped curve; When the ventilator switches from the inspiratory phase to the expiratory phase, when the transition curve is an exponential curve, it satisfies the following formula: CP(t)=CP1+(CP2-CP1)×(1-e -t×4 / CT ) t∈(0,CT) When the transition curve is a straight line, it satisfies the following formula: CP(t)=CP1+(CP2-CP1)×t / CT t∈(0,CT) When the transition curve CP(t) is an S-shaped curve, it satisfies the following equation: Where CP(t) represents the specific PEEP valve control amount, t represents the time when the relative adjustment starts, CP1 and CP2 are the inspiratory phase control amount and expiratory phase control amount when switching from the inspiratory phase to the expiratory phase, respectively, and CT is the switching time; When the ventilator switches from the expiratory phase to the inspiratory phase, when the transition curve is an exponential curve, it satisfies the following formula: CP(t)=CP3+(CP4-CP3)×(1-e -t×4 / CT ) t∈(0,CT) When the transition curve is a straight line, it satisfies the following formula: CP(t)=CP3+(CP4-CP3)×t / CT t∈(0,CT) When the transition curve is an S-shaped curve, it satisfies the following formula: Where CP(t) represents the specific PEEP valve control amount, t represents the time when the relative adjustment starts, CP3 and CP4 represent the inspiratory phase control amount and the expiratory phase control amount when switching from the expiratory phase to the inspiratory phase, respectively, and CT represents the switching time.

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