System for controlling a pressure support device

Abstract

The present disclosure relates to systems and methods for controlling a pressure level of a gas mixture delivered to a patient via a pressure support device adapted to provide respiratory support to the patient over time. More specifically, the systems and methods described herein enable accurate detection of active inspiration of a patient and rapid triggering of increased inspiratory positive airway pressure pulses. Further, the described systems and methods rely on patient pressure measured along the turbulent gas flow path, and find particular applications when the pressure support device is configured to provide non-zero positive end expiratory pressure.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 63 / 350,438, filed on June 9, 2022, the contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to systems and methods of controlling a pressure support device and, more particularly, to systems and methods of controlling the pressure level of a gas mixture delivered to a patient via a pressure support device. Background Art

[0004] Positive pressure support devices, such as ventilators, continuous positive airway pressure ("CPAP") machines, and the like, are a class of medical devices that support the breathing of patients with impaired breathing. In some of these devices, such as CPAP machines, airflow is supplied to the patient at a constant pressure level, and thus the operation of these devices does not need to be synchronized with the patient's breathing. In other devices, such as ventilator systems, the patient's breathing is supported by delivering airflow at pressure levels that vary over time. More specifically, the pressure support pulses at a higher inspiratory positive airway pressure ("IPAP") pressure level during inspiration and at a lower positive end expiratory pressure ("PEEP") pressure level during exhalation. Therefore, the action of such devices must be synchronized with the patient's active breathing to ensure proper respiratory support. In addition, the method used to determine the optimal time to trigger the pressure pulse will depend largely on the type and design of the ventilator system and the availability of sensor data. Summary of the invention

[0005] According to an embodiment of the present disclosure, a system for controlling the pressure level of a gas mixture delivered to a patient is provided. The system may include one or more processors in communication with a ventilation system, and a memory storing instructions that, when executed by the one or more processors, cause the system to perform the following operations: (1) receiving a patient pressure signal from a pressure sensor of the ventilation system; (2) generating one or more pressure triggers by: (a) determining a derivative signal based on the patient pressure signal; (b) determining a smoothed derivative signal based on the patient pressure signal and / or the derivative signal; and (c) extracting one or more pressure triggers based on the smoothed derivative signal, wherein the one or more pressure triggers indicate an active inspiratory phase of the patient's breathing; and (3) providing instructions to the ventilation system to modify the pressure level of the gas mixture delivered to the patient based on the one or more pressure triggers.

[0006] In one aspect, the system is configured to continuously receive patient pressure signals over a plurality of breathing cycles of the patient.

[0007] In one aspect, a pressure trigger is generated within 500 milliseconds for each active inspiratory phase of a plurality of breathing cycles of the patient.

[0008] In one aspect, the one or more pressure triggers are not generated during any exhalation phase of the plurality of breathing cycles of the patient.

[0009] In one aspect, the instructions provided to the ventilation system include increasing the pressure level of the gas mixture delivered to the patient to a higher inspiratory positive airway pressure for a period of time.

[0010] In one aspect, generating one or more pressure triggers further comprises: applying a predetermined smoothing coefficient to determine a smoothed derivative signal; and applying a predetermined slope limit and a predetermined minimum inspiratory duration to the smoothed derivative signal to extract the one or more pressure triggers.

[0011] In one aspect, each of the one or more pressure triggers corresponds to a time when the smoothed derivative signal falls below a predetermined slope limit for at least a predetermined minimum inspiratory duration.

[0012] According to another embodiment of the present disclosure, a ventilation system for delivering a gas mixture to a patient is provided. The ventilation system may include: a gas source; a gas delivery line operably connected to the gas source; and a patient airway interface operably connected to the gas delivery line and defining a gas flow path from the gas source to the patient, wherein the patient airway interface includes a patient pressure sensor and one or more entrainment holes along the gas flow path, the one or more entrainment holes being configured to allow the patient to breathe ambient air. The ventilation system may also include a control system having one or more processors adapted to control delivery of a gas mixture from at least a gas source to a patient via a gas flow path; and a memory storing instructions that, when executed by the one or more processors, cause the ventilation system to perform the following operations: (1) deliver the gas mixture to the patient at a first pressure level via a patient airway interface and a gas flow path; (2) receive a patient pressure signal from a patient pressure sensor; (3) generate one or more pressure triggers by: (a) determining a derivative signal based on the patient pressure signal; (b) determining a smoothed derivative signal based on the patient pressure signal and / or the derivative signal; and (c) extracting one or more pressure triggers based on the smoothed derivative signal, wherein the one or more pressure triggers indicate an active inspiratory phase of the patient's breathing; and (4) modifying the pressure level of the gas mixture delivered to the patient based on the one or more pressure triggers.

[0013] In one aspect, delivery of the gas mixture through the gas flow path and the patient airway interface generates a region of negative pressure in the gas flow path at the one or more entrainment apertures.

[0014] In one aspect, a patient pressure sensor is positioned along the gas flow path proximate a region of negative pressure generated by delivery of a gas mixture through the gas flow path and the patient airway interface.

[0015] In one aspect, the first pressure level is a positive end expiratory pressure greater than zero.

[0016] In one aspect, the pressure level of the gas mixture delivered to the patient is modified by increasing the pressure level from a first pressure level to a second pressure level, the second pressure level being a higher inspiratory positive airway pressure.

[0017] In one aspect, a combination of a gas mixture from at least a gas source and air entrained through one or more entrainment apertures provides ventilatory support to a patient.

[0018] According to another embodiment of the present disclosure, a method of controlling a ventilation system attached to a patient is provided. The method may include: (1) delivering a gas mixture to a patient at a first pressure level via a patient airway interface and a gas flow path of a ventilation system; (2) receiving a patient pressure signal from the patient using a patient pressure sensor, the patient pressure sensor being located along the gas flow path near a negative pressure region generated by the delivery of the gas mixture; (3) generating one or more pressure triggers by: (a) determining a derivative signal based on the patient pressure signal; (b) determining a smoothed derivative signal by applying a predetermined smoothing coefficient to the patient pressure signal and / or the derivative signal; and (c) extracting one or more pressure triggers based on the smoothed derivative signal by applying a predetermined slope limit and a predetermined minimum inspiratory duration to the smoothed derivative signal, wherein the one or more pressure triggers indicate an active inspiratory phase of the patient's breathing; (4) providing instructions to the ventilation system to modify the pressure level of the gas mixture delivered to the patient based on the one or more pressure triggers; and (5) modifying the pressure level of the gas mixture delivered to the patient over a period of time based on the provided instructions, wherein the pressure level is modified by increasing the pressure level of the gas mixture delivered to the patient to a higher inspiratory positive pressure ventilation during the period of time.

[0019] In one aspect, a patient pressure signal is continuously received from a patient pressure signal over a plurality of breathing cycles of the patient, one or more pressure triggers are generated for each active inspiratory phase of the plurality of breathing cycles of the patient, and a gas mixture is delivered to the patient at a higher inspiratory positive airway pressure during a time period within 500 milliseconds of each active inspiratory phase of the plurality of breathing cycles of the patient.

[0020] These and other aspects of the various embodiments will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In the drawings, like reference numerals generally refer to like parts throughout the different views. Also, the drawings are not necessarily drawn to scale, emphasis instead generally being placed upon illustrating the principles of the various embodiments.

[0022] Figure 1 is a block diagram illustrating a ventilation system according to aspects of the present disclosure.

[0023] Figure 2 is a diagram illustrating airflow through a portion of a patient airway interface in accordance with aspects of the present disclosure.

[0024] Figure 3 is a schematic diagram illustrating a system for controlling pressure levels of associated pressure support devices in accordance with aspects of the present disclosure.

[0025] Figure 4 is a block diagram illustrating certain types of process variables in accordance with aspects of the present disclosure.

[0026] Figure 5 is a graph illustrating a first simulated patient pressure signal over a period of time in accordance with aspects of the present disclosure.

[0027] Figure 6 is a graph illustrating a patient pressure signal, a patient muscle activation signal, and an example trigger signal according to aspects of the present disclosure.

[0028] Figure 7 is a graph illustrating a patient pressure signal and an unsmoothed derivative signal in accordance with aspects of the present disclosure.

[0029] Figure 8 The time from t = 8.5 seconds to t = 11.5 seconds is shown. Figure 7 Graph of part of .

[0030] Fig. 9 is a graph illustrating a patient pressure signal and a smoothed derivative signal in accordance with aspects of the present disclosure.

[0031] Fig.10 The time from t = 8.5 seconds to t = 11.5 seconds is shown. Fig. 9 Graph of part of .

[0032] Fig.11 is a diagram illustrating a method of performing a multi-axis rotation of a vehicle having one or more slope limits according to aspects of the present disclosure. Fig.10 Plot of the smoothed derivative signal.

[0033] Fig.12 It is a graphic Fig.10 One or more generated pressure-triggered graphs on a graph.

[0034] Fig.13 is a graph illustrating one or more generated pressure triggers over a longer period of time in accordance with aspects of the present disclosure.

[0035] Fig.14 is a graph illustrating a smoothed derivative signal having one or more slope limits between t=9 seconds and t=9.5 seconds.

[0036] Fig.15 is a graph illustrating a smoothed derivative signal having one or more slope limits between t=10 seconds and t=10.5 seconds.

[0037] Fig.16 is a graph illustrating one or more generated pressure triggers after applying a minimum inhalation duration in accordance with aspects of the present disclosure.

[0038] Fig.17 is a graph illustrating a plurality of generated pressure triggers over a longer period of time after applying a minimum inhalation duration in accordance with aspects of the present disclosure.

[0039] Fig.18 is a graph illustrating a second simulated patient pressure signal over a period of time in accordance with aspects of the present disclosure.

[0040] Fig.19 It is a diagram illustrating various aspects of the present disclosure. Fig.18 Graph of the patient pressure signal and the smoothed derivative signal.

[0041] Fig. 20 is a diagram illustrating a method of performing a multi-axis rotation of a vehicle having one or more slope limits according to aspects of the present disclosure. Fig.19 The smoothed derivative part of the signal.

[0042] Fig.21 FIG. 1 is an illustration of a pressure-triggered system with one or more slope limits and extraction according to aspects of the present disclosure. Fig.19 Graph of a portion of a patient pressure signal and a smoothed derivative signal.

[0043] Fig. 22 It is a diagram illustrating various aspects of the present disclosure. Fig.21 Plot of the smoothed derivative signal.

[0044] Fig.23 It is a diagram illustrating various aspects of the present disclosure. Fig.18 FIG. 4 is a graph of a patient pressure signal and a corresponding pressure trigger from t=0 seconds to t=90 seconds.

[0045] Fig.24 It is a diagram illustrating various aspects of the present disclosure. Fig.19 Graph of the patient pressure signal and the corresponding pressure trigger from t=90 seconds to t=170 seconds.

[0046] Fig.25A and Fig.25B is a flow chart illustrating a method of controlling the pressure level of a ventilation system according to aspects of the present disclosure. DETAILED DESCRIPTION

[0047] The present disclosure relates to systems and methods for controlling a pressure support device. More specifically, the present disclosure relates to systems and methods for controlling the pressure level of a gas mixture delivered to a patient via a pressure support device, which is suitable for providing time-varying respiratory support to the patient. As described herein, the system and method enable pressure pulse control that is triggered only during the active inspiratory phase of the patient's respiratory cycle (i.e., never during the expiratory phase), wherein each inspiratory phase that meets specific criteria is supported by a pressure pulse, and wherein the trigger delay (i.e., the time between detecting the active inspiratory phase and triggering the pressure pulse) is no greater than about 500 milliseconds. In addition, the systems and methods described herein are adapted to function solely based on a measured patient pressure as described below, but it is contemplated that other techniques, methods, and devices may be used in conjunction with the measured patient pressure.

[0048] Steering Figure 1 , a block diagram of a ventilation system 100 with an integrated pressure control subsystem 102 is illustrated, according to aspects of the present disclosure. When the ventilation system 100 is used, the ventilation system 100 is attached to a patient's respiratory system 104, through which the patient breathes normally while receiving mechanical support via a patient airway interface 106. In an embodiment, the patient airway interface 106 can be a non-invasive interface, such as a non-invasive open nasal interface. In addition to the patient airway interface 106, the ventilation system 100 can include a gas delivery line 108 operably connected to a gas source 110 (e.g., an oxygen source 110A and / or a compressed air source 110B). At least the gas delivery line(s) 108 and the patient airway interface 106 will define a gas flow path 112 from the gas source(s) 110A, 110B to the patient's respiratory system 104.

[0049] In an embodiment, the ventilation system 100 also includes a patient pressure sensor 114, which is disposed along the gas flow path 112 and is adapted to measure the pressure generated by each breathing cycle (e.g., inhalation and exhalation cycle) of the patient. In a particular embodiment, the patient pressure sensor 114 can be disposed within the patient airway interface 106.

[0050] refer to Figure 2The patient airway interface 106 may also include one or more entrainment holes 202. Figure 2 As shown, a main flow 208 of the gas mixture may be delivered to the patient's respiratory system 104 through the narrow opening 204 of the patient airway interface 106. During normal operation, the ventilation system 100 may provide ventilatory support in the form of a time-varying main gas flow 208 (e.g., a gas mixture) delivered to the patient 104. That is, the pressure level and flow rate of the main gas flow 208 may vary over time via the ventilation system 100.

[0051] In one aspect, the mainstream 208 is delivered at a first pressure level greater than zero (i.e., a baseline pressure level). For example, during the exhalation phase of the patient's breathing cycle, the airflow 208 can be delivered at a positive end-expiratory pressure ("PEEP") pressure level. In a specific embodiment, the first pressure level is greater than zero cmH2O, including from about 1 cmH2O to about 10 cmH2O, from about 2 cmH2O to about 9 cmH2O, from about 3 cmH2O to about 8 cmH2O, from about 4 cmH2O to about 7 cmH2O, from about 5 cmH2O to about 6 cmH2O and any combination of their endpoints.

[0052] According to the present disclosure, since the primary airflow 208 may be forced through the narrow opening 204, entrainment of ambient air 206 may occur within a portion of the patient airway interface 106. That is, the primary airflow 112 is forced to flow along the gas flow path 112, which includes the narrow opening 204, which generates a negative pressure region(s) 210 at one or more entrainment apertures 202 in the gas flow path 112. Although effective retention of ambient air is generated, the velocity of the mainstream 208 within the patient airway interface 106 will be very high (i.e., close to the speed of sound), which will produce significant fluctuations and step changes in the flow pattern within this region of the patient airway interface 106. As a result, the total airflow of the patient cannot be measured within the patient airway interface 106 of such a ventilation system 100, and the measured patient pressure (i.e., the pressure generated by the patient's breathing) will contain a large amount of artifacts and noise.

[0053] According to certain aspects of the present disclosure, a system 300 for controlling the pressure level of a gas mixture 112 delivered to a patient 104 is described. Figure 3 , schematically illustrates one such system 300. The pressure control system 300 may include one or more processors 302 (also referred to as central processing units or CPUs), machine-readable memory 304, and an interface bus 306, all of which may be interconnected and / or in communication via a system bus 308 comprising conductive circuit paths through which instructions (e.g., machine-readable signals) may propagate to accomplish communications, tasks, storage, etc.

[0054] In an embodiment, one or more processors 302 may include a high-speed data processor sufficient to execute program components, which may include various special processing units known in the art. The general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. In some embodiments, one or more features described herein may be implemented on components such as application specific integrated circuits ("ASICs"), digital signal processors ("DSPs"), field programmable gate arrays ("FPGAs"), or similar electronic devices.

[0055] In an embodiment, the interface bus 306 may include an input interface / output interface 310 configured to connect the system 300 to one or more peripheral devices (e.g., patient pressure sensor 114, pressure regulator 128, ventilator module 116, etc.); a network interface 312 configured to connect the pressure control system 300 to a communication network 316 (e.g., using a network protocol such as IEEE 802.3 and / or 802.11), and / or a storage interface 314 configured to accept, communicate and / or connect to a plurality of machine-readable storage devices (e.g., storage device 318, removable storage devices, etc.).

[0056] In various aspects, the network interface 312 can operably connect the pressure control system 300 to a communication network 316, which can include direct interconnects, the Internet, a local area network ("LAN"), a metropolitan area network ("MAN"), a wide area network ("WAN"), a wired or Ethernet connection, a wireless connection, and similar types of communication networks, including combinations thereof. In some embodiments, one or more user devices 320 and / or a database 322 can be connected to the pressure control system 300 via the communication network 316 and the network interface 312.

[0057] In embodiments, memory 304 may variously be embodied as one or more forms of machine-accessible and machine-readable memory, including various types of storage devices 318, random access memory 324, and read-only memory 326. In some aspects, storage device 318 may include non-transitory storage media, magnetic disk storage, optical disk storage, storage device arrays, solid-state storage devices, and the like, including combinations thereof.

[0058] In an embodiment, the memory 304 may include a pressure trigger module 328, which includes a collection of program and / or database components and / or data (e.g., data 330). In one aspect, for example, the data 330 may include one or more process variables 352, including but not limited to smoothing coefficients, slope limits, inspiratory duration, etc. (described below and Figure 4 Depending on the particular implementation, the pressure trigger module 328 may include software components, hardware components, and / or some combination of hardware and software components.

[0059] In certain embodiments, the pressure trigger module 328 may include, but is not limited to, instructions 332 having a sensor component 334, a pressure trigger component 336, and an output component 336. These components may be incorporated into, loaded from, loaded onto, or otherwise operably used with the pressure control system 300. Similarly, the pressure control system 300 may be incorporated into, loaded from, loaded onto, or otherwise operably used with the ventilation system 100 and operably obtained from the ventilation system 100. For example, while the program components may be stored in the local storage device 318, they may also be loaded and / or stored in other storage, such as a remote cloud storage facility accessible via a communication network (e.g., the communication network 316).

[0060] The memory 304 of the pressure control system 300 may also include an operating system component 340. The operating system component 340 may be an executable program component that facilitates the operation of the pressure control system 300. Typically, the operating system component 340 is configured to facilitate access to I / O, network, and storage interfaces, and may communicate with other components of the pressure control system 300.

[0061] In an embodiment, the sensor component 332 can be a stored program component executed by at least one processor, such as one or more processors 302 of the pressure control system 300. In particular, the sensor component 332 can be configured to measure and / or receive a patient pressure signal 342 from the pressure sensor 114 of the ventilation system 100. In an embodiment, the patient pressure signal 342 can include multiple breathing cycles of the patient. That is, the patient pressure signal 342 can be received continuously and / or in real time. In one aspect, each breathing cycle of the patient can include an inhalation phase and an exhalation phase, so the patient pressure signal 342 can include one or more inhalation phases and one or more exhalation phases. The sensor component 332 can then provide the received patient pressure signal 342 to the pressure trigger component 334.

[0062] In an embodiment, the pressure trigger component 334 can be a stored program component executed by at least one processor, such as one or more processors 302 of the pressure control system 300. Specifically, the pressure trigger component 334 can be configured to generate one or more pressure triggers 344. Each pressure trigger 344 indicates the active inspiratory phase of the patient's breathing (i.e., a breathing cycle), and therefore indicates when the gas flow 208 should be delivered to the patient 104 at a higher inspiratory positive airway pressure ("IPAP") pressure level 346.

[0063] In an embodiment, the pressure trigger component 334 can be configured to: (i) determine the derivative signal 350 based on the patient pressure signal 342; (ii) determine the smoothed derivative signal 350 based on the patient pressure signal 342 and / or the derivative signal 350 using one or more smoothing coefficients 402; and (iii) extract one or more pressure triggers 344 based on the smoothed derivative signal 350. In one aspect, the smoothed derivative signal 350 can be determined and smoothed in one step. For example, the patient pressure signal 342 can be used to perform the following operations:

[0064]

[0065] in

[0066]

[0067] Where dPy / dt is the smoothed derivative signal 350, Δt is the time step, Lf( Figure 4 The “LF value” 408 shown in FIG. 4 is an integer greater than zero corresponding to the number of data points to be smoothed, Co k is the smoothing coefficient 352, Py is the patient pressure signal 342, and k, i, and m are integers greater than zero.

[0068] In some embodiments, Lf value 408 can be about 2 to about 50, including about 5 to about 40, about 10 to about 30, about 15 to about 20, about 8 to about 32, and any combination thereof. However, Lf value 408 is preferably minimized to avoid excessive trigger delays.

[0069] In an embodiment, the pressure trigger component 334 can also be configured to: (iv) apply one or more predetermined slope limits 404 to the smoothed derivative signal 350; (v) apply one or more predetermined minimum inspiratory durations 406 to the smoothed derivative signal 350; (vii) apply one or more predetermined minimum peak distances 410 to the smoothed derivative signal 350; (viii) determine one or more slope limits 404 to be applied to the smoothed derivative signal 350; (ix) determine one or more minimum inspiratory durations 406; (xi) determine one or more minimum peak distances 410; and / or (x) determine one or more Lf values ​​408. In one aspect, one or more process variables 352 can be predetermined or preset by a physician or therapy provider, or can be adjusted by the pressure control system 300 and / or the patient to meet the patient's physiological needs.

[0070] In one aspect, the slope limit 404 can be from about ±2 cmH2O / s to about ±20 cmH2O / s, including from about ±3 cmH2O / s to about ±15 cmH2O / s, from about ±5 cmH2O / s to about ±10 cmH2O / s, from about ±7 cmH2O / s to about ±9 cmH2O / s, and any combination of points thereof.

[0071] In one aspect, one or both of the first pressure level 348 and the second pressure level 346 (i.e., the lower PEEP pressure level 348 and the higher IPAP pressure level 346) can be pre-set by a physician or therapy provider, or can be adjusted by the patient himself. In a specific embodiment, the first pressure level 348 can be from about 0.0 cmH2O to about 30 cmH2O, including from about 0.0 cmH2O to about 10 cmH2O. In one aspect, the first pressure level 348 is greater than 0.0 cmH2O and less than 30 cmH2O, or greater than 0.0 cmH2O and less than about 10 cmH2O. In another embodiment, the second pressure level 346 can be from about 2 cmH2O to about 30 cmH2O, including from about 2 cmH2O to about 20 cmH2O, and from about 10 cmH2O to about 20 cmH2O. In one aspect, the second pressure level 346 is greater than the first pressure level 348.

[0072] Steering Figures 5 to 17 The disclosed systems and methods are now described and illustrated in conjunction with simulated data of an adult with chronic obstructive pulmonary disease ("COPD") breathing 20 times per minute, actively expiring with a constant primary flow, producing a PEEP pressure level 348 of approximately 5.3 cmH2O. The sampling rate of the simulated data was Δt=2 ms.

[0073] like Figure 5As shown, a patient pressure signal (Py) 342 for multiple breathing cycles is illustrated between t=10 seconds and t=20 seconds. The wide depressions or valleys correspond to the patient's inspiratory phase, while the wide peaks correspond to the patient's expiratory phase. However, as described above, the patient pressure signal 342 contains a large amount of noise, as shown by the spikes and step changes, which can be caused by fluctuations in the flow pattern within the patient airway interface 106.

[0074] In some conventional pressure support devices, the patient's muscle pressure signals can be used to determine when to trigger respiratory support. Figure 6 FIG. 3 shows a patient pressure signal (Py) 342, a simulated patient muscle pressure signal (Pmus), and a trigger output signal (ASL5000 trigger) at the start of a Pmus maneuver over about one respiratory cycle between t=10 seconds and t=13 seconds. Although the patient muscle pressure signal (Pmus) can be used to easily trigger pressure support in conventional pressure support devices, it is mainly dependent on the patient's muscle pressure signal (Pmus). Figure 5 The noisy patient pressure signal (Py) 342 shown in FIG. 3 is not important.

[0075] According to the present disclosure, the pressure control system 300 may generate and / or determine a derivative signal (dPy / dt) 350 based on the patient pressure signal (Py) 342 described herein. For example, Figure 7 and Figure 8 The derivative signal (dPy / dt) 350 shown in FIG. 1 is determined using an Lf value of 1 (i.e., no smoothing). However, as described above, the derivative signal (dPy / dt) 350 is still very noisy. In particular, Figure 8 The graph shows the time from t = 8.5 seconds to t = 11.5 seconds. Figure 7 , which shows a derivative signal (dPy / dt) 350 having a plurality of "valleys" 800 that may indicate the onset of an active inspiratory phase even when the patient pressure signal (Py) 342 does not support such a conclusion.

[0076] Thus, as described herein, the pressure control system 300 may be configured to apply a smoothing process to the patient pressure signal (Py) 342 and / or the derivative signal (dPy / dt) 350 to obtain a smoothed derivative signal (dPy / dt) 350. For example, Fig. 9 and Fig.10 The derivative signal (dPy / dt) 350 shown in FIG. 1 is obtained using an Lf of 16. When comparing Figure 8 The derivative signal (dPy / dt) 350 and Fig.10 When the derivative signal (dPy / dt) is 350, Fig.10 The derivative signal (dPy / dt) 350 shown contains significantly less "noise"

[0077] Using the smoothed derivative signal (dPy / dt) 350, the pressure control system 300 may apply one or more predetermined slope limits 404 to determine one or more pressure triggers 344 corresponding to the onset of the active inspiratory phase of the patient's breathing cycle. Fig.11 , a slope limit 404 of ±8 cmH2O / s is applied to the smoothed derivative signal (dPy / dt) 350 to identify several points 1102, 1104, 1106, 1108 where the smoothed derivative signal (dPy / dt) 350 drops below the slope lower limit 404.

[0078] However, if Fig.12 As shown, due to the noisy patient pressure signal (Py) 342, after the patient's active inspiration phase (i.e., triggers 1204, 1206, and 1208), the four pressure triggers 1202, 1204, 1206, and 1208 generated corresponding to the four points 1102, 1104, 1106, and 1108 still do not correctly trigger pressure support. Fig.13 As shown, these false triggers 1302 accumulate significantly when observing even a short period of time (i.e., t=8.5 seconds to t=26 seconds). At each of these points, the associated ventilator system 100 incorrectly triggered the delivery of increased pressure gas flow that was opposite to the patient's actual breathing cycle.

[0079] Therefore, in an embodiment, the pressure control system 300 may apply one or more predetermined minimum inspiration durations 406 to the smoothed derivative signal (dPy / dt) 350 to extract the correct one or more pressure triggers 344. This step is referred to as Fig.14 (shown between t=9 seconds and t=9.5 seconds Fig.11 The smoothed derivative signal (dPy / dt) 350) and Fig.15 (shown between t=10 seconds and t=10.5 seconds Fig.11 As shown, the intersection 1102 is followed by a duration 1402 from about 9.066 seconds to about 9.359 seconds or about 293 milliseconds. Fig.15 As shown, the intersection points 1104, 1106, and 1108 are followed by corresponding durations 1404, 1406, 1408 of approximately 27.3 milliseconds, approximately 11.7 milliseconds, and approximately 5.9 milliseconds, respectively.

[0080] refer to Fig.16By applying one or more predetermined minimum inspiratory durations 406, incorrect triggers (e.g., triggers 1204, 1206, 1208) can be eliminated, leaving only triggers (e.g., trigger 1202) that correctly correspond to the active inspiratory phase of multiple breathing cycles of the patient. In an embodiment, the minimum inspiratory duration 406 can be preset by a physician and / or therapy provider, or can be determined by the pressure control system 300 as described above. In certain aspects, the minimum inspiratory duration 406 can be from about 30 milliseconds to about 120 milliseconds. Fig.16 In the example shown, the minimum inspiratory duration is 40 milliseconds (or 20 data points at a resolution of Δt = 2 milliseconds).

[0081] like Fig.17 As shown, the pressure control system 300 utilized in accordance with the present disclosure can properly trigger 1702 the simulated patient pressure signal (Py) 342 with a total trigger delay (i.e., the time between the start of inspiration and the detection of inspiration) of less than about 500 milliseconds. In certain embodiments, the total trigger delay in accordance with the present disclosure can be less than about 450 milliseconds, less than about 400 milliseconds, less than about 350 milliseconds, less than about 300 milliseconds, less than about 250 milliseconds, less than about 200 milliseconds, less than about 150 milliseconds, and / or less than about 100 milliseconds.

[0082] In an embodiment, it may be necessary to further apply one or more minimum peak distances 410 to the smoothed derivative signal (dPy / dt) 350 before extracting one or more pressure triggers 344. In particular, if the start of the exhalation phase is detected (i.e., when the derivative signal and / or the smoothed derivative signal 350 is greater than the positive predetermined slope limit 404), the pressure control system 300 may apply the minimum distance threshold 410 to ensure proper triggering of breathing support.

[0083] For example, refer to Figures 18 to 24 A second simulation was performed using the ASL 5000 lung simulator and the "normal adult" lung model at 15 breaths per minute and "passive exhalation". Fig.18 As exemplified in FIG. 1 , a primary flow rate that produces a stepwise increase in a "PEEP" pressure level from about 0 to about 22 cmH2O is used with an analog sampling rate of 5 ms (ie, Δt=5 ms). In particular, Fig.18 As shown, a patient pressure signal (Py) 342 is generated and the increasing primary flow (eg, primary flow 208 ) creates an upward trend in the patient pressure signal (Py) 342 until the primary flow 208 stops at approximately t=160 seconds.

[0084] like Figures 5 to 17In the illustrated example, the pressure control system 300 may determine a smoothed derivative signal (dPy / dt) 350 based on a patient pressure signal (Py) 350 to begin extracting one or more pressure triggering times 344 . Fig.18 The smoothed derivative signal (dPy / dt) 350 of the patient pressure signal (Py) 350 shown in FIG. Fig.19 350. In this example, an Lf factor of 16 is used to determine the smoothed derivative signal (dPy / dt) 350.

[0085] Then, refer to Fig. 20 and Fig.21 , the pressure control system 300 can apply one or more slope limits 404 and a minimum inspiratory duration 406 to the smoothed derivative signal (dPy / dt) 350. This results in generating one or more pressure triggering moments 344 (e.g., pressure triggers 2102, 2104, 2106, 2108). Fig.21 As shown, the triggering moments 2102, 2104, 2106, 2108 correspond to points 2122, 2124, 2126, 2128 when the smoothed derivative signal (dPy / dt) 350 transitions from being greater than the negative slope limit 404 to being less than the negative slope limit 404. Here, the slope limit 404 is ±4 cmH2O / s, and the minimum inspiratory duration is at least 100 milliseconds. However, as Fig.21 As shown, although the patient pressure signal (Py) 342 indicates that the patient is in the exhalation phase 2130, 2132, the pressure triggering time 2102, 2106 is incorrectly generated. Therefore, in an embodiment, the pressure control system 300 can apply the minimum peak distance 410 to ensure the correct triggering of the ventilation system 100.

[0086] In an embodiment, the minimum peak distance 410 may be defined as the distance between the triggering moment and the previous positive peak at which the smoothed derivative signal (dPy / dt) 350 is greater than the positive slope limit. Fig. 22 , showing Figures 19 to 214, 404). The smoothed derivative signal (dPy / dt) 350 is shown. The points 2122, 2124, 2126, 2128 where the smoothed derivative signal (dPy / dt) 350 drops below the negative slope limit 404 (i.e., -4 cmH2O / s) are indicated along with the points 2222, 2224, 2226, 2228 where the smoothed derivative signal (dPy / dt) 350 rises above the positive slope limit 404 (i.e., +4 cmH2O / s). Based on the determination of the minimum peak distance 410, each potential pressure triggering moment 2122, 2124, 2126, 2128 can be compared to the moment before it when the smoothed derivative signal (dPy / dt) 350 exceeds the positive slope limit 404. As shown in the following table, applying the minimum peak distance 410 to points 2122, 2124, 2126, and 2128 correctly extracts points 2124, 2128, which correspond to the inspiratory phase of the patient's breathing cycle according to the patient pressure signal (Py) 342:

[0087] Table 1. Minimum peak distances for 1.5 s application

[0088]

[0089] Therefore, distances 2232 and 2236 do not satisfy the minimum peak distance 410, while distances 2234 and 2236 satisfy the requirement of the minimum peak distance 410. Fig.23 and Fig.24 As shown, the one or more triggering moments 344 extracted based on the smoothed derivative signal (dPy / dt) 350 now correctly correspond to each inspiratory phase of the patient's breathing cycle.

[0090] In an embodiment, the minimum peak distance 410 can be preset by a physician and / or therapy provider. In other aspects, the minimum peak distance 410 can be determined by the pressure control system 300 based on, for example, but not limited to, the patient's previous breathing cycle. In one aspect, the minimum peak distance 410 is from about 0.5 seconds to about 2 seconds, including from about 0.5 seconds to about 0.75 seconds, from about 0.75 seconds to about 1.0 seconds, from about 1.0 seconds to about 1.25 seconds, from about 1.25 seconds to about 1.5 seconds, from about 1.5 seconds to about 1.75 seconds, from about 1.75 seconds to about 2.0 seconds, and any combination of endpoints thereof.

[0091] Back to Figure 1 , the ventilation system 100 may be a wearable ventilator with a portable air source(s) 110A, 110B. The ventilator module 116 may include or communicate with one or more other functional accessories. For example, the control system 102 may include an interface bus (e.g., Figure 3), which is suitable for transmitting information about the patient, the patient's therapy, and the performance of the ventilation system 100 to a remote location for inspection, analysis, remote intervention, two-way communication, and / or archiving. In one aspect, the patient's compliance with therapy and / or utilization of therapy can be monitored and evaluated. In other aspects, important information can be extracted and analyzed, including the patient's respiratory rate, I:E ratio, oxygen usage, activity level, depth of breathing, etc. In yet other aspects, the ventilator module 116 can receive information from an external source, such as programming instructions for setting titration options for the ventilator output to meet patient needs or for sending instructions to the patient.

[0092] In an embodiment, the oxygen source 110A and / or the compressed air source 110B may be included outside the ventilator module 116. In other embodiments, the oxygen source 110A and / or the compressed air source 110B may be inside the ventilator module 116, for example, if the therapy is used for fixed use (at home, hospital, outpatient facility, etc.). A gas mixer 118 may be included to control the O2 fraction delivered to the gas delivery line 108. One or more sensors may be included in the sensor suite 120, including but not limited to a pulse oximeter, a pedometer, a CO2 sensor, and / or the like suitable for titrating the settings of the ventilator module 116 to meet the patient's physiological needs (e.g., setting the correct oxygen mixer 118 settings or ventilator volume output). The ventilation system 100 may also include a drug delivery system 122, an air conditioner 124 (e.g., a humidifier and / or dehumidifier), a flow regulator 126, a pressure regulator 128, a filtration system 130, and / or a user interface 132. One or more of these components 118 , 120 , 122 , 124 , 126 , 128 , 130 , 132 may be internal or external to the ventilator module 116 .

[0093] In one aspect, the drug delivery system 122 can be adapted to deliver aerosolized drugs pharmacologically propelled and / or deposited deep within the patient's respiratory system 104 without a carrier propellant.

[0094] In one aspect, the user interface 132 may include a display screen suitable for displaying information about therapy provided by the ventilation system 100, including one or more settings, and suitable for receiving user input that can be used by the control system 102 (e.g., to control one or more settings of the ventilation system 100 and / or the ventilator module 116).

[0095] Also provided herein is a method of controlling a ventilation system 100 attached to a patient. Fig.25A and Fig.25B , one such method 2500 is illustrated according to aspects of the present disclosure.

[0096] In step 2502, method 2500 may include supplying gas mixture 208 to a patient (ie, patient airway 104) via pressure support device 100. Gas mixture 208 may be delivered to the patient via patient airway interface 106 and gas flow path 112 of ventilation system 100 at a first pressure level.

[0097] In step 2504, the method 2500 can include measuring (e.g., in real time) the patient's breathing using the pressure sensor 114. In an embodiment, the measurement can be a patient pressure signal (Py) 342. In one aspect, as described above, the patient pressure sensor 114 can be disposed along the gas flow path 112.

[0098] In step 2506, method 2500 may include receiving a patient pressure signal (Py) 342 of the patient. In an embodiment, patient pressure signal (Py) 342 may be received by control system 102 of ventilation system 100 and / or pressure trigger module 328 of pressure control system 300. In one aspect, pressure trigger module 328 may be integrated into control system 102 such that ventilation system 100 includes pressure control system 300.

[0099] In step 2508, method 2500 may optionally include determining at least one smoothing coefficient 402 for the patient. Alternatively, one or more smoothing coefficients 402 may be preset by a physician and / or therapy provider.

[0100] In steps 2510 and 2512, the method 2500 may include determining the derivative signal (dPy / dt) 350 based on the patient pressure signal (Py) 342, and applying the smoothing coefficient(s) 402 to the derivative signal (dPy / dt) 350 and / or the patient pressure signal (Py) 342. In certain embodiments, steps 2510 and 2512 may be performed simultaneously. That is, the derivative signal (dPy / dt) 350 may be determined and smoothed simultaneously.

[0101] In steps 2514, 2516, and 2518, method 2500 may optionally include determining one or more slope limits 404, one or more minimum inspiratory durations 406, and one or more minimum peak distances 410 for the patient, as described above. Alternatively, one or more of these process variables 352 may be preset by a physician and / or therapy provider to meet the patient's physiological needs.

[0102] In steps 2520 and 2522, method 2500 may include applying one or more process variables 352 to the smoothed derivative signal (dPy / dt) 350 to extract one or more pressure triggers 344. In one aspect, one or more pressure triggers 344 indicate an active inspiratory phase of the patient's breathing.

[0103] In step 2524, the method 2500 may include modifying the delivery of the gas flow 208. If the pressure control system 300 is external to the ventilation system 100, it may be necessary (in step 2524) to provide instructions to the ventilation system 100 to modify the pressure level of the gas mixture 208 delivered to the patient. As used herein, the term "instruction" refers to a digital signal containing data (e.g., a pressure trigger 344) in a format that allows the ventilation system 100 to at least know when to deliver or modify the pressure level of the gas flow 208. In an embodiment, the pressure level can be modified by increasing the pressure level from a first pressure level 348 (i.e., a lower PEEP pressure level) to a second pressure level 346 (i.e., a higher IPAP pressure level). In one aspect, the second pressure level 346 can be maintained by the ventilation system 100 for a period of time corresponding to the patient's inspiratory phase. In other words, once the patient begins the expiratory phase, the pressure level of the gas flow 208 is reduced back to the first pressure level 348 and / or another pressure level lower than the second pressure level 346.

[0104] As described herein, a patient pressure signal (Py) 342 may be continuously received from patient pressure sensor 114 over a plurality of breathing cycles of the patient, one or more pressure triggers 344 may be generated for each active inspiratory phase of the plurality of breathing cycles of the patient, and gas mixture 208 may be delivered to the patient at a higher inspiratory positive airway pressure 346 during a time period having a trigger delay of less than 500 milliseconds after the onset of each active inspiratory phase of the plurality of breathing cycles of the patient.

[0105] It should be understood that all combinations of the foregoing concepts and additional concepts discussed in more detail below (provided that such concepts are not mutually inconsistent) are considered part of the inventive subject matter disclosed herein. In particular, all combinations of the claimed subject matter appearing at the end of this disclosure are considered part of the inventive subject matter disclosed herein. It should also be understood that terms explicitly used herein that may also appear in any disclosure incorporated by reference should be given a meaning most consistent with the specific concepts disclosed herein.

[0106] All definitions defined and used herein should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0107] Unless expressly indicated to the contrary, the indefinite articles "a" and "an" as used in this specification and the claims should be understood to mean "at least one".

[0108] The phrase "and / or" as used in this specification and claims should be understood to mean "one or both" of the elements so connected, i.e., elements present in conjunction in some cases and separate in other cases. Multiple elements listed with "and / or" should be interpreted in the same manner, i.e., "one or more" of the elements so connected. In addition to the elements specifically identified by the "and / or" clause, other elements may optionally be present, whether or not related to those elements specifically identified.

[0109] "Or" used in this specification and claims should be understood to have the same meaning as "and / or" defined above. For example, when separating items in a list, "or" or "and / or" should be interpreted as inclusive, i.e., including at least one, but also including more than one multiple or series of elements, and optionally, additional unlisted items. Only terms that are clearly indicated to the contrary, such as "only one of..." or "exactly one of...", or when used in the claims, "consisting of...", will refer to including exactly one element of a plurality or series of elements. In general, the term "or" used herein should only be interpreted as meaning exclusive alternatives (i.e., "one or the other, but not two") before exclusive terms such as "any one", "one of...", "only one of..." or "exactly one of...".

[0110] As used in this specification and claims, the phrase "at least one" when referring to a list of one or more elements should be understood to mean at least one element selected from any one or more elements in the list of elements, but does not necessarily include at least one element of each element specifically listed in the list of elements, nor does it exclude any combination of elements in the list of elements. This limitation also allows that elements may optionally be present in addition to the elements specifically identified in the list of elements referred to by the phrase "at least one", whether or not related to those elements specifically identified.

[0111] In the claims and the foregoing description, all transitional phrases, such as "comprising", "including", "carrying", "having", "including", "involving", "holding", "consisting of", etc., shall be understood as open-ended, i.e., meaning including but not limited to. Only the transitional phrases "consisting of" and "consisting essentially of" shall be closed or semi-closed transitional phrases, respectively.

[0112] It should also be understood that in any method claimed herein that includes more than one step or action, the order of the steps or actions of the method are not necessarily limited to the order in which the steps or actions of the method are described unless explicitly indicated to the contrary.

[0113] The above examples of the described subject matter can be implemented in a variety of ways. For example, some aspects can be implemented using hardware, software, or a combination thereof. When any aspect is implemented at least in part with software, the software code can be executed on any suitable processor or processor set, whether provided in a single device or computer or distributed in multiple devices / computers.

[0114] The present disclosure may be implemented as a system, method and / or computer program product at any possible level of integrated technical detail. The computer program product may include a computer-readable storage medium (or medium) having computer-readable program instructions thereon for causing a processor to implement various aspects of the present disclosure.

[0115] A computer-readable storage medium may be a tangible device that can retain and store instructions for use by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing devices. A non-exhaustive list of more specific examples of computer-readable storage media includes the following: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are recorded, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium should not be interpreted as being a transient signal itself, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagated through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0116] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to a corresponding computing / processing device, or to an external computer or external storage device, via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical transmission fibers, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network, and forwards the computer-readable program instructions to be stored in a computer-readable storage medium in the corresponding computing / processing device.

[0117] The computer-readable program instructions for implementing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, integrated circuit configuration data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and procedural programming languages, such as "C" programming language or similar programming languages. The computer-readable program instructions may be executed completely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer, partially on a remote computer, or completely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., by using the Internet of an Internet service provider). In some examples, electronic circuits including, for example, programmable logic circuits, field programmable gate arrays (FPGAs), or programmable logic arrays (PLAs) may be executed by using the state information of computer-readable program instructions to personalize the electronic circuit to execute computer-readable program instructions so as to implement various aspects of the present disclosure.

[0118] This article describes various aspects of the present disclosure with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the examples of the present disclosure. It should be understood that each frame of the flowchart and / or block diagram and the combination of frames in the flowchart and / or block diagram can be implemented by computer-readable program instructions.

[0119] Computer-readable program instructions may be provided to a processor of a special-purpose computer or other programmable data processing device to produce a machine, so that instructions executed by the processor of the computer or other programmable data processing device can create equipment for implementing the functions / actions specified in the blocks (one or more) of the flowchart and / or block diagram. These computer-readable program instructions may also be stored in a computer-readable storage medium, which can instruct a computer, a programmable data processing device, and / or other equipment to operate in a particular manner, so that the computer-readable storage medium having the instructions stored therein includes an article of manufacture, which includes instructions for implementing various aspects of the functions / actions specified in the flowchart and / or block diagram or multiple blocks.

[0120] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operating steps to be performed on the computer, other programmable apparatus, or other device, thereby producing a computer-implemented process, so that the instructions executed on the computer, other programmable apparatus, or other device implement the functions / actions specified in the box(es) of the flowchart and / or block diagram.

[0121] The flow chart and block diagram in the figure illustrate the architecture, functionality and operation of the possible implementation of the system, method and computer program product according to various examples of the present disclosure. In this regard, each frame in the flow chart or block diagram can represent a module, a fragment or a part of an instruction, which includes one or more executable instructions for implementing a specified logical function (one or more). In some alternative implementations, the function marked in the frame may not occur in the order marked in the figure. For example, the two frames shown in succession can actually be executed substantially at the same time, or these blocks can sometimes be executed in reverse order, depending on the functionality involved. It will also be noted that each block in the block diagram and / or the flow chart diagram and the combination of the blocks in the block diagram and / or the flow chart diagram can be implemented by a system based on special-purpose hardware, which implements a specified function or action or implements a combination of special-purpose hardware and computer instructions.

[0122] Other implementations are within the scope of the following claims and other claims to which the applicant may be entitled.

[0123] Although several inventive embodiments have been described and illustrated herein, a person of ordinary skill in the art can easily conceive of various other means and / or structures for implementing the functions and / or obtaining the results and / or one or more advantages described herein, and such changes and / or modifications are considered to be within the scope of the inventive embodiments described herein. More generally, it will be readily understood by those skilled in the art that all parameters, dimensions, materials, and configurations described herein are exemplary, and the actual parameters, dimensions, materials, and / or configurations will depend on the specific application in which the teachings of the present disclosure are used. Those skilled in the art will recognize, or be able to determine using only routine experiments, many equivalents of the specific inventive embodiments described herein. Therefore, it should be understood that the foregoing embodiments are given by way of example only, and within the scope of the appended claims and their equivalents, the embodiments of the present disclosure may be implemented in a manner different from that specifically described and required. The inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and / or methods, if such features, systems, articles, materials, kits, and / or methods are not mutually contradictory, is included in the scope of the invention of the present disclosure.

Claims

1. A system for controlling the pressure level of a gas mixture delivered to a patient, comprising: one or more processors in communication with the ventilation system; as well as A memory storing instructions, which, when executed by the one or more processors, cause the system to perform the following operations: receiving a patient pressure signal from a pressure sensor of the ventilation system; Generate one or more pressure triggers by: determining a derivative signal based on the patient pressure signal; determining a smoothed derivative signal based on the patient pressure signal and / or the derivative signal; and extracting the one or more pressure triggers based on the smoothed derivative signal, wherein the one or more pressure triggers are indicative of an active inspiratory phase of respiration of the patient; and Instructions are provided to the ventilation system to modify the pressure level of the gas mixture delivered to the patient based on the one or more pressure triggers. 2 . The system of claim 1 , wherein the system is configured to continuously receive the patient pressure signal over a plurality of breathing cycles of the patient.

3. The system of claim 2, wherein a pressure trigger is generated within 500 milliseconds for each active inspiratory phase of the plurality of breathing cycles of the patient.

4. The system of claim 1, wherein the one or more pressure triggers are not generated during any expiratory phase of the plurality of breathing cycles of the patient.

5. The system of claim 1, wherein the instructions provided to the ventilation system include increasing the pressure level of the gas mixture delivered to the patient to a higher inspiratory positive airway pressure for a period of time.

6. The system of claim 1 , wherein generating the one or more pressure triggers further comprises: applying a predetermined smoothing coefficient to determine the smoothed derivative signal; as well as A predetermined slope limit, a predetermined minimum inspiratory duration, and / or a predetermined minimum peak distance are applied to the smoothed derivative signal to extract the one or more pressure triggers.

7. The system of claim 6, wherein each of the one or more pressure triggers corresponds to when the smoothed derivative signal falls below the predetermined slope limit and remains below the predetermined slope limit for at least the predetermined minimum inspiratory duration.

8. A ventilation system for delivering a gas mixture to a patient, the ventilation system comprising: Gas source; a gas delivery line operably connectable to the gas source; a patient airway interface operably connectable to the gas delivery line and defining a gas flow path from the gas source to the patient, wherein the patient airway interface includes a patient pressure sensor and one or more entrainment apertures along the gas flow path, the one or more entrainment apertures configured to allow the patient to breathe ambient air; a control system comprising one or more processors and a memory, the one or more processors being adapted to control delivery of the gas mixture from at least the gas source to the patient via the gas flow path, the memory storing instructions that, when executed by the one or more processors, cause the ventilation system to: delivering the gas mixture to the patient via the patient airway interface and the gas flow path at a first pressure level; receiving a patient pressure signal from the patient pressure sensor; Generate one or more pressure triggers by: determining a derivative signal based on the patient pressure signal; determining a smoothed derivative signal based on the patient pressure signal and / or the derivative signal; and extracting the one or more pressure triggers based on the smoothed derivative signal, wherein the one or more pressure triggers are indicative of an active inspiratory phase of respiration of the patient; The pressure level of the gas mixture delivered to the patient is modified based on the one or more pressure triggers.

9. The ventilation system of claim 8, wherein delivery of the gas mixture through the gas flow path and the patient airway interface generates a region of negative pressure in the gas flow path at the one or more entrainment apertures.

10. The ventilation system of claim 9, wherein the patient pressure sensor is disposed along the gas flow path proximate the negative pressure region generated by delivery of the gas mixture through the gas flow path and the patient airway interface.

11. The ventilation system of claim 8, wherein the first pressure level is a positive end-expiratory pressure greater than zero.

12. The ventilation system of claim 11, wherein the pressure level of the gas mixture delivered to the patient is modified by increasing the pressure level from the first pressure level to a second pressure level, the second pressure level being a higher inspiratory positive airway pressure.

13. The ventilation system of claim 8, wherein a combination of the gas mixture from at least the gas source and air entrained through the one or more entrainment holes provides ventilatory support to the patient.

14. A method of controlling a ventilation system attached to a patient, the method comprising: delivering a gas mixture to the patient at a first pressure level via a patient airway interface and a gas flow path of the ventilation system; receiving a patient pressure signal from the patient using a patient pressure sensor, the patient pressure sensor being located along the gas flow path proximate a region of negative pressure generated by delivery of the gas mixture; Generate one or more pressure triggers by: determining a derivative signal based on the patient pressure signal; determining a smoothed derivative signal by applying a predetermined smoothing factor to the patient pressure signal and / or the derivative signal; and extracting one or more pressure triggers based on the smoothed derivative signal by applying a predetermined slope limit, a predetermined minimum inspiratory duration, and / or a predetermined minimum peak distance to the smoothed derivative signal, wherein each pressure trigger corresponds to an active inspiratory phase of respiration of the patient; The pressure level of the gas mixture delivered to the patient over a period of time is modified based on the one or more pressure triggers, wherein the pressure level is modified by increasing the pressure level of the gas mixture delivered to the patient from the first pressure level to a higher inspiratory positive airway pressure over the period of time.

15. The method of claim 14, wherein the patient pressure signal is continuously received from the patient pressure sensor during multiple breathing cycles of the patient, the one or more pressure triggers are generated for each active inspiratory phase of the multiple breathing cycles of the patient, and the delivery of the gas mixture is modified within 500 milliseconds of each active inspiratory phase of the multiple breathing cycles of the patient.

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