Safe ventilation in the presence of respiratory effort

Abstract

The mechanical ventilation device includes at least one electronic controller configured to receive imaging data regarding dimensions of a patient's diaphragm during inspiration and expiration while the patient is receiving mechanical ventilation therapy with an associated mechanical ventilator, calculate a pressure value of the patient's chest based on at least the imaging data, and, when the calculated pressure value does not meet an acceptance criterion, output a warning indicating that the calculated pressure value does not meet the acceptance criterion and output a recommended adjustment to one or more parameters of the mechanical ventilation therapy delivered to the patient.

Description

[Technical Field]

[0001] This patent application claims priority under 35 U.S.C. § 119 to U.S. Provisional Patent Application No. 63 / 407,772, filed September 19, 2022, the contents of which are incorporated herein by reference.

[0002] The following relates generally to respiratory therapy techniques, mechanical ventilation techniques, mechanical ventilation weaning techniques, ventilator-associated lung injury (VILI) techniques, and related techniques. [Background technology]

[0003] Clinicians can use the respiratory system's pressure-volume (PV) loop and parameter estimates (e.g., resistance and compliance) to monitor a patient's condition and provide safe ventilation therapy to the patient. The most accurate results are obtained using transpulmonary pressure, which is available through esophageal catheter measurements. However, the catheter is often not present, and in such cases, the estimate is affected by the presence of patient effort and chest wall mechanics. Therefore, modern ventilators avoid patient effort and ignore chest wall mechanics when determining transpulmonary pressure.

[0004] Respiratory therapists can use the PV loop as a guide to select the correct ventilator settings to prevent atelectasis and hyperinflation (VILI). The ventilator can display the PV loop on the screen. Because transpulmonary pressure is responsible for deformation of the lung tissue (i.e., the parenchyma that contains the alveoli), the ventilator should use the transpulmonary pressure to accurately create a PV loop. Transpulmonary Pressure P l is the difference between intrathoracic pressure and alveolar pressure.

[0005] However, current techniques require the use of a catheter, making it difficult to measure transpulmonary pressure (see, for example, Umbrello, M. and Chiumello, D., 2018, “Interpretation of the transpulmonary pressure in the critically ill patient”, Ann Transl Med 2018;6(19):383). Therefore, ventilators rely on the pressure P measured at the airway opening. wye and the derived alveolar pressure P alv This method is accurate if there is no respiratory effort by the patient. The greater the patient's respiratory effort, the greater the P alv and P l The difference between the two becomes large, reducing the accuracy of the PV loop.

[0006] Therefore, setting the correct pressure and volume is particularly relevant for patients with compromised lungs who are ventilated with other ventilation modalities such as pressure-support ventilation (PSV), proportional-assist ventilation (PAV, PAV+), and, for example, NAVA if the patient is making an effort. Summary of the Invention [Problem to be solved by the invention]

[0007] However, it is difficult to measure or determine transpulmonary pressure in a non-invasive manner so that safe ventilation can be provided in a more accurate and convenient manner (i.e., without the use of a catheter and without avoiding or circumventing patient effort in determining transpulmonary pressure).

[0008] The following discloses specific improvements to overcome these and other problems. [Means for solving the problem]

[0009] In one aspect, the mechanical ventilation device comprises: receiving imaging data relating to dimensions of the patient's diaphragm during inspiration and expiration while the patient is receiving mechanical ventilation therapy with an associated mechanical ventilator; calculating a pressure value in the patient's chest based on at least the imaging data; and When the calculated pressure value does not meet an acceptance criterion, at least one of outputting a warning indicating that the calculated pressure value does not meet the acceptance criterion and outputting a recommended adjustment to one or more parameters of mechanical ventilation therapy delivered to the patient. The at least one electronic controller is configured to:

[0010] In another aspect, a method of mechanical ventilation includes, using at least one electronic controller, receiving imaging data relating to dimensions of the patient's diaphragm during inspiration and expiration while the patient is receiving mechanical ventilation therapy with an associated mechanical ventilator; calculating a pressure value in the patient's chest based at least on the imaging data; when the calculated pressure value does not meet an acceptance criterion, performing at least one of the steps of outputting a warning indicating that the calculated pressure value does not meet an acceptance criterion and outputting a recommended adjustment to one or more parameters of mechanical ventilation therapy delivered to the patient; Includes.

[0011] One benefit is the prevention of VILI in patients undergoing mechanical ventilation.

[0012] Another advantage resides in determining transpulmonary pressure in patients undergoing mechanical ventilation.

[0013] Another advantage resides in adjusting ventilator settings when delivering mechanical ventilation therapy to a patient based on the calculated patient transpulmonary pressure.

[0014] Another advantage resides in automatically adjusting mechanical ventilator settings to assist patients in weaning from mechanical ventilation therapy.

[0015] Another advantage is that it provides mechanical ventilation without the use of invasive catheters or dedicated ventilation techniques to measure the patient's transpulmonary pressure.

[0016] Another advantage resides in using the detected rate of diaphragm thickening to wean the patient off mechanical ventilation.

[0017] Another advantage resides in the use of ultrasound to measure diaphragmatic response non-invasively.

[0018] A given embodiment may provide none, one, two, more, or all of the advantages discussed above, and / or other advantages that will become apparent to those skilled in the art upon reading and understanding this disclosure. [Brief explanation of the drawings]

[0019] The disclosure may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting the disclosure. [Figure 1] FIG. 1 illustrates a schematic diagram of an exemplary mechanical ventilation device according to the present disclosure. [Figure 2] FIG. 2 shows an exemplary flowchart of operations suitably performed by the device of FIG. [Figure 3] FIG. 3 shows a schematic diagram of the operation of the flowchart of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0020] In the specification, unless the context clearly dictates otherwise, a plural number includes a plural number. In the specification, the expression "coupled," "connected," or "engaged" to two or more parts or components means that, as long as they are interlocked, these parts are joined, operate, or work together, either directly or indirectly, i.e., through one or more intermediate parts or components. Directional expressions used in the specification, such as, but not limited to, top, bottom, left, right, above, below, front, rear, and their derivatives, relate to the orientation of the elements shown in the drawings and do not limit the scope of the claimed invention, unless expressly stated otherwise. The word "comprises" or "includes" does not exclude the presence of elements or steps other than those described in the specification and / or recited in the claims. In a device consisting of several means, several of these means may be embodied by one and the same item of hardware.

[0021] Referring to FIG. 1 , a mechanical ventilator 2 is shown for providing ventilation therapy to an associated patient P. As shown in FIG. 1 , the mechanical ventilator 2 includes an outlet 4 connectable to a patient breathing circuit 5 for delivering mechanical ventilation to the patient P. The patient breathing circuit 5 includes typical components for a mechanical ventilator, such as an inlet line 6, an optional outlet line 7 (which is omitted if the ventilator uses a single-limbed patient circuit), a connector or port 8 for connecting to an endotracheal tube (ETT) 16, and one or more respiratory sensors (not shown), such as, for example, a gas flow meter, a pressure sensor, and / or an end-tidal carbon dioxide (etC2) sensor. The mechanical ventilator 2 is designed to deliver air, an air-oxygen mixture, or other breathable gas (not shown) to the outlet 4 at a programmed pressure and / or flow rate to ventilate the patient via the ETT. The mechanical ventilator 2 also includes an electronic controller 13 (eg, an electronic processor or microprocessor), a display device 14, and a non-transitory computer-readable medium 15 that stores instructions executable by the electronic controller 13.

[0022] FIG. 1 diagrammatically illustrates an intubated patient P with an ETT 16 (the bottom of the ETT is shown in phantom because it is inside the patient P). A connector or port 8 connects with the ETT 16 and operatively connects with a mechanical ventilator 2 to deliver breathable air to the patient P through the ETT 16. Mechanical ventilation provided by the mechanical ventilator 2 through the ETT 16 is therapeutic for a wide range of diseases, such as various types of lung diseases like emphysema or pneumonia, viral or bacterial infections that affect breathing, e.g., COVID-19 infection or severe influenza, or cardiovascular diseases, in which the patient P receives oxygen-enriched breathable gas.

[0023] 1 shows a patient P who has already been intubated. That is, FIG. 1 shows the patient after tracheal intubation, which involves inserting an ETT 16 into the patient. However, to safely perform tracheal intubation, an anesthesiologist or other qualified medical professional first evaluates the patient P to select an ETT size for the ETT 16, and then inserts the selected size ETT into the patient P via the tracheal intubation procedure.

[0024] 1 also shows a medical imaging device 18 (also referred to as an image acquisition device, imaging device, etc.). As primarily described herein, the medical imaging device 18 comprises an ultrasound (US) medical imaging device 18. In other embodiments, the image acquisition device 18 can be a computed tomography (CT) image acquisition device, such as a C-arm imager, or other X-ray imaging device, a magnetic resonance (MR) image acquisition device, or a medical imaging device of another modality. As described herein, the medical imaging device 18 is used to acquire ultrasound images of a patient P.

[0025] In some embodiments, the medical imaging device 18 may comprise a wearable ultrasound (US) imaging device 18. In a more specific example, the medical imaging device 18 includes an ultrasound transducer 20 that can be worn by the patient P, for example, by a belt or patch (e.g., at a suitable location on the patient P's abdomen or chest to image the patient's diaphragm, as shown in FIG. 1 ). The ultrasound transducer 20 is positioned to acquire ultrasound imaging data 24 (i.e., ultrasound images) of the patient P's diaphragm. For example, the ultrasound transducer 20 is configured to acquire ultrasound imaging data 24 of the patient P's diaphragm, and more specifically, to acquire diaphragm muscle pressure (P ) of the patient P's chest. mus ) to determine the position of at least the diaphragm of the patient P during inspiration and expiration while the patient P is receiving mechanical ventilation therapy using the mechanical ventilator 2. In another example, the ultrasound imaging data 24 relates to the thickness of the diaphragm of the patient P during inspiration and expiration while the patient P is receiving mechanical ventilation therapy using the mechanical ventilator 2.

[0026] In some embodiments, an additional imaging device (e.g., a CT imaging device 26 as shown in FIG. 1 ) acquires one or more CT images 28 of the patient P. In particular, the CT images 28 may include imaging data of at least the chest wall of the patient P. In another example, the additional imaging device 26 may be an X-ray imaging device configured to acquire X-ray images of the patient P. It should be noted that the CT imaging device 26 does not have to be located in the same room or department as the mechanical ventilator 2. For example, the CT imaging device 26 may be located in a radiology room, while the mechanical ventilator 2 may be located in an intensive care unit (ICU), a cardiac care unit (CCU), or a room assigned to the patient P. This is indicated schematically in FIG. 1 by the dividing line L.

[0027] In some embodiments, database 30 may store previously acquired CT (or X-ray) images 28. These images 28 may be retrieved from database 30 for processing by electronic controller 13. Like CT imaging device 26, database 30 does not have to be located in the same room or department (or in the same room or department) as mechanical ventilator 2. As shown schematically in FIG. 1 , database 30 is located on the same side of dividing line L as CT imaging device 26.

[0028] In some embodiments, previously acquired CT images 28 of patient P are used to generate a biomechanical model 32 of the thoracic structures (including the lungs), including the chest wall, of patient P. This model 32 is used as a reference point for analyzing current CT images 28 of patient P. Model 32 is stored in database 30 (or in non-transitory computer-readable medium 15 of mechanical ventilator 2).

[0029] The non-transitory computer-readable medium 15 may store instructions executable by the electronic controller 13 to perform a mechanically assisted method or process 100 for monitoring a patient P during mechanical ventilation using the mechanical ventilator 2. With reference to FIG. 2 and with continued reference to FIG. 1, an exemplary embodiment 100 of the mechanical ventilation method is shown generally as a flow chart. To begin the method 100, the patient P is intubated with an ETT 16 so that mechanical ventilation using the mechanical ventilator 2 can be initiated, and an ultrasound transducer 20 is attached to the patient so that imaging of the patient P can begin.

[0030] In operation 102, imaging data is received by electronic controller 13. This imaging data may include data regarding dimensions of patient P's diaphragm during inspiration and expiration while patient P is receiving mechanical ventilation therapy via mechanical ventilator 2. The received imaging data includes ultrasound imaging data 24 acquired by ultrasound transducer 20, and includes the thickness, thickness change, and / or position of patient P's diaphragm during inspiration and expiration.

[0031] In some embodiments, the received imaging data includes a CT image 28 acquired by a CT imaging device 26, the CT image 28 including at least the chest wall of the patient P. In some embodiments, the received imaging data may include previously acquired images stored in a database 30 and / or may further include retrieving a model 32 of the patient P.

[0032] In some embodiments, the electronic controller 13 may also receive data acquired by the mechanical ventilator 2. This ventilator data may include, for example, airflow during inspiration of the patient P and airflow pressure in the airway of the patient P during mechanical ventilation therapy.

[0033] In operation 104, the electronic controller 13 calculates a pressure value in the chest of the patient P (i.e., transpulmonary pressure (P)) based on the received data. l ), and tidal variation of transpulmonary pressure (DP l In one embodiment, the device is configured to calculate the transpulmonary pressure (P l ) may be calculated based on the ultrasound imaging data 24, the CT images 28, and data received from the mechanical ventilator 2, etc. In certain embodiments, the electronic controller 13 (i) calculates the diaphragm muscle pressure (P) from the ultrasound imaging data 24 in operation 101. mus ), and (ii) in operation 103, determine chest wall elastance (E cw ) is configured to determine the diaphragm muscle pressure (P mus ) and chest wall elastance (E cw ) is the transpulmonary pressure (P) in the chest of patient P, along with airway pressure / flow data from mechanical ventilator 2. l ) is used to calculate

[0034] 3 shows a schematic diagram of operation 104 as a circuit. The circuit connects the respiratory system of a patient P to: Total flow resistance in the respiratory system R rs , and two compliances C of the lung and chest wall, respectively l and C cw It is expressed using Q air is the airflow during inspiration. The transpulmonary pressure P l is the difference between the intrapleural pressure and the alveolar pressure, P l =P alv -P pl Airway pressure P wye and flow rate Q air is continuously measured by the mechanical ventilator 2 and is the flow resistance in the respiratory system R rs is determined using a dedicated ventilation technique by the mechanical ventilator 2 (eg, a least squares procedure performed by the electronic controller 13).

[0035] In FIG. 3, pressure (from left to right as shown in FIG. 3) is the airway opening pressure (P wye ), alveolar pressure (P aly ), intrathoracic pressure (P pl ), and inspiratory muscle pressure (P mus The "equation of motion" of the respiratory system in Figure 3 is expressed as Equation (1) P wye -P mus =Q air R rs +V T / C l +V T / C cw (1) where V T is the air flow Q air Another formula for the pressure drop in the airways due to flow resistance is given by equation (2): P wye =P alv +Q air R rs (2) Using equation (2), P wye By finding the value of , equation (1) can be rewritten as equation (3). P alv -P mus =V T / C l +V T / C cw (3) The alveolar pressure is determined from the mechanical ventilator 2 by equation (2) P alv =P wye -Q air R rs It is possible.

[0036] V in Equation (1) T / C l The term is given by Equation (4) V inhale =FRC+V T (4) represents the elastic work (i.e., pressure change) required to deform the lung from its functional residual capacity (FRC) to the volume at the end of inspiration. This change in elastic pressure is the change (i.e., fluctuation) in transpulmonary pressure during breathing, DP l =V T / C l To determine the absolute value of the transpulmonary pressure, the pretension (i.e., elastic preload) value is calculated using equation (5): P l =P l,0 +DP l (5) The pretension or preload P l,0Pretension is the tension that keeps the lungs inflated at the end of expiration in the absence of respiratory muscle activity. This pretension is the result of a balance between the chest wall's tendency to expand (protrude) and the lungs' tendency to contract. This is why, without ventilator support, intrathoracic pressure becomes negative even with zero muscle force. The nature of this pretension becomes apparent when there is a puncture of the pleural sac, in which case the lung collapses (i.e., pneumothorax).

[0037] This pretension value is used to calculate the transpulmonary pressure (P) in the chest of patient P, as shown in operation 105 in FIG. l ) can be used as further inputs to calculate the functional residual capacity (FRC) and lung compliance 1 / C l =1 / C rs -1 / C cw From, elastic preload P l,0 =FRC / C l It is possible to estimate the respiratory muscle pressure. mus When V = 0, the pressures exerted by the chest wall and lungs are in equilibrium, and the volume is V = FRC. When the lungs collapse and there is no tension, the volume is V = 0. Experiments show that the resting volume RV (i.e., the minimum volume obtained by exhalation) is much larger than the volume when the lungs are completely collapsed (when there is no rib cage around the lungs). Therefore, V = 0 is considered a reasonable assumption or estimate. The relationship between pressure and volume is linear. Quantitative analysis of CT images can be used to measure FRC.

[0038] VT / C in formula (1) cw The term represents the elastic recoil of the chest wall (i.e., the elastic recoil force). During perfectly normal breathing, this term is negative because the chest wall tends to "pop out," in which case the elasticity of the chest wall cooperates with the diaphragm muscle during volumetric expansion of the lungs.

[0039] P mus and C cw can be determined using imaging data of patient P. If these parameters are known and V T and Palv If ρ is continuously available from the mechanical ventilator 2, then the variation in transpulmonary pressure can be calculated on a breath-by-breath basis by (rewriting equation (1) as equation (6)): DP l =V T / C l =P alv -P mus -V T / C cw (6)

[0040] Inspiratory muscle pressure P mus can be determined from the ultrasound imaging data 24 acquired by the ultrasound transducer 20. The diaphragm muscle pressure P mus can be estimated from ultrasound imaging data 24 of the diaphragm in different ways. In one embodiment, P mus A patient-specific biomechanical model 32 is applied to calculate the diaphragm muscle travel distance x obtained from the ultrasound measurements 24. d and the pressure from the ventilator 2 as inputs, and the muscle pressure P exerted by the diaphragm on the lungs and chest wall mus The advantage of the biomechanical model is that P mus The estimation of the biomechanical model 32 can be performed offline. The biomechanical model 32 estimates the diaphragm travel distance x d P as a function of mus Simulate x d P as a function of mus is stored in a look-up table (not shown) in non-transitory computer readable medium 15. The look-up table is then used in real time.

[0041] In another example, a skeletal muscle model with a force-length relationship for muscle fibers can be used (see, e.g., Zhang et al., BioMed Eng OnLine (2016) 15:18, "Biomechanical simulation of thorax deformation using finite element approach"). In such a model, the force generated by a muscle fiber can be determined from the contraction (force-length relationship) of the muscle fiber. The contraction (change in thickness and length) of the diaphragm muscle during the patient's inspiratory effort is measured using ultrasound (e.g., diaphragm thickening factor TFDI and diaphragm displacement). Muscle force is converted to muscle pressure by dividing by the projected area of ​​the diaphragm (i.e., piston model). P mus =F mus / A d

[0042] Chest wall compliance C cw can be determined, for example, from CT images 28 acquired by CT imaging device 26. Chest wall compliance during inspiration, C cw can be determined in different ways. In one example, indirect measurement using a positive end-expiratory pressure (PEEP) step method (PSM) can be performed by the electronic controller 13 (see, e.g., Persson, P. et al., 2018, “Evaluation of lung and chest wall mechanics during anesthesia using the PEEP-step method”, British Journal of Anaesthesia, 120 (4): 860e867 (2018)). PSM can be used to measure P mus = 0, the pulmonary compliance C l Provide 1 / C rs =1 / C l +1 / C cwAccording to [1], the inverse of chest wall compliance is the difference between the inverse of respiratory system compliance and the inverse of lung compliance. Chest wall compliance is less sensitive to disease than lung compliance. PSM procedures can be performed in the early ICU phase while the patient is still fully sedated. The measured C cw can then be used when there is respiratory effort.

[0043] In another example, a direct measurement process using a mouthpiece can be performed that requires cooperation from the patient (see, e.g., Gideon, EA et al., 2021, “The effect of estimating chest wall compliance on the work of breathing during exercise as determined via the modified Campbell diagram,” Am J Physiol Regul Integr Comp Physiol 320: R268-R275). In another example, a lookup table with chest wall stiffness values ​​based on patient information such as age and gender can be used (see, e.g., Gideon).

[0044] In another example, an algorithm is provided for calculating chest wall stiffness based on CT scans. A finite element model of the chest is constructed based on segmentation of the CT scan (see, e.g., Zhang). The mechanical properties of the structures (intercostal muscles, diaphragm, bone, cartilage, tendons) are known. The effective chest wall stiffness (the inverse of compliance) can be calculated by applying a pressure ΔP in a direction normal to the chest wall (as a boundary condition) and subsequently determining the simulated volume change ΔV from the model output. E cw =1 / C cw =ΔP / ΔV Optionally, the finite element model can take into account tissue (i.e., fat) around the chest or abdomen, patient position (e.g., prone, supine), or gravity to assess abdominal pressure.

[0045] Similarly, lung compliance can be determined. However, chest wall compliance is less sensitive to disease characteristics, and chest wall structural and material properties are less sensitive to inter-individual variability (bone stiffness is known to be less variable than parenchymal tissue). Therefore, it is advantageous to focus on chest wall compliance.

[0046] In another example, a machine learning algorithm is provided for calculating chest wall stiffness (i.e., compliance). The model uses imaging data (e.g., CT and X-rays), data from a mechanical ventilator (V), and T ,P alv ), and catheter data (esophageal pressure P es The trained model takes imaging data and mechanical ventilation data as input and is trained using P es provides as output. Subsequently, lung and chest wall compliances can be calculated, C l =V T / (P alv -P es ) and 1 / C cw =1 / C rs +1 / C l is.

[0047] 1 and 2, in operation 106, the electronic controller 13 calculates the calculated pressure value (P l ,DP l ) meets predetermined acceptance criteria. For example, the electronic controller 13 may be configured to compare the ultrasound image 24 and the calculated pressure values ​​(P l ,DP l ) can be analyzed to determine the effort exerted by the patient P. The electronic controller 13 calculates the calculated pressure value (P l ,DP lIf it is determined that the calculated pressure value (P l ,DP l ) does not meet the acceptance criteria. This acceptance criteria may be, for example, a pressure value (P l ,DP l ) exceeding its threshold. This warning output is done by displaying a message on the display device 14 of the mechanical ventilator 2, whereby the calculated pressure value (P l ,DP l ) can be shown to medical professionals that the

[0048] In another exemplary embodiment, in operation 110, a recommended adjustment to one or more parameters of the mechanical ventilation therapy delivered to the patient P is output. Again, this output is accomplished by displaying a message on the display device 14 of the mechanical ventilator 2, thereby displaying the calculated pressure (P l ,DP l ) can be shown to medical professionals that the

[0049] In a further exemplary embodiment, in operation 112, the mechanical ventilator 2 is controlled to adjust one or more parameters of the mechanical ventilation therapy delivered to the patient P. When operation 112 is performed, the pressure value (P l ,DP l ) is recalculated, and this recalculated pressure value (P l ,DP l ) may be analyzed to determine whether acceptance criteria are met. It will be appreciated that two or more of operations 108, 110, and 112 may be performed (e.g., a warning may be displayed and settings on mechanical ventilator 2 may be adjusted). In some embodiments, at least one of operations 102-106 and operations 108-112 may be repeated iteratively to generate calculated pressure values ​​(P l,DP l ) meets acceptance criteria.

[0050] In certain embodiments, the display device 14 of the mechanical ventilator 2 is configured to display a pressure-volume (PV) curve 30 of the lungs of the patient P (shown schematically as a box in FIG. 1 ) during mechanical ventilation therapy. The pressure portion of the PV curve 30 is displayed as a calculated pressure value (P l ,DP l ), and the volume portion of the PV curve 30 is the lung volume of the patient P as determined by the CT image 28 (or biomechanical model 32). In this embodiment, the acceptance criteria is the range of values ​​defined by the displayed PV curve 30. The calculated pressure value (P l ,DP l When the calculated pressure value (P) is outside the range of values ​​defined by the displayed PV curve 30, one or more of the actions 108, 110, and / or 112 (e.g., outputting a warning, displaying a recommended adjustment, or controlling the ventilator 2 to adjust the ventilator 2 settings) may be taken. l ,DP l ) is within the above range, the pressure value (P l ,DP l ) is the calculated pressure value (P l ,DP l ) is calculated continuously during mechanical ventilation therapy for patient P to ensure that it is within the above range of values.

[0051] Modern ventilators are capable of measuring the overall compliance of the respiratory system. The measurement procedure avoids patient effort (e.g., by taking measurements at zero flow or during exhalation). However, doing so in a reliable and accurate manner is difficult due to the steep slope of the flow curve. As a result, even small deviations result in large errors. In addition to looking at the PV curve 30, ultrasound imaging data 24 of the diaphragm is used to detect when the patient is not making an effort. To do so, the mechanical ventilator 2 can be synchronized with the ultrasound transducer 20. P mus (or a proxy such as TFDI) can be used to plot the PV curve 30 for display on the display device 14. Respiratory system compliance C rs is P (determined from the volume) mus It can be determined from areas with no flow or pressure.

[0052] The present disclosure has been described with reference to preferred embodiments. Modifications and alterations may occur to others upon reading and understanding the above detailed description. It is intended that the exemplary embodiments be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

1. 1. A mechanical ventilation device having at least one electronic controller, said at least one electronic controller comprising: receiving imaging data relating to dimensions of the patient's diaphragm during inspiration and expiration while the patient is receiving mechanical ventilation therapy with an associated mechanical ventilator; calculating a pressure value in the patient's chest based on at least the imaging data; and When the calculated pressure value does not meet the acceptance criteria, outputting a warning indicating that the calculated pressure value does not meet the acceptance criteria; and and outputting recommended adjustments to one or more parameters of the mechanical ventilation therapy delivered to the patient. Do at least one of the following:

1. A mechanical ventilation device configured to:

2. The at least one electronic controller determining diaphragm muscle pressure from the received imaging data; and Calculating the pressure value based on at least the calculated diaphragm muscle pressure.

2. The mechanical ventilation device of claim 1, configured to calculate the pressure value by:

3. 3. The mechanical ventilation device of claim 2, further comprising a wearable ultrasound transducer configured to acquire at least a portion of the imaging data as ultrasound imaging data of at least the patient's diaphragm.

4. 4. The mechanical ventilation device of claim 3, wherein the ultrasound imaging data includes the position of at least the patient's diaphragm during inspiration and expiration while the patient is undergoing mechanical ventilation therapy to determine changes in diaphragm muscle pressure and diaphragm thickness of the diaphragm.

5. The at least one electronic controller determining chest wall compliance from the received imaging data; and calculating the pressure value based at least on the determined chest wall compliance.

2. The mechanical ventilation device of claim 1, configured to calculate the pressure value by:

6. The mechanical ventilation device of claim 5 , further comprising an imaging device configured to acquire at least a portion of imaging data of at least a chest wall of the patient.

7. The at least one electronic controller generating a model of the patient's chest wall; and determining chest wall compliance from the received imaging data and the generated model of the chest wall; 7. The mechanical ventilation device of claim 6, further configured to:

8. The mechanical ventilation device of claim 6 , wherein the imaging device comprises one of a computed tomography (CT) imaging device or an X-ray imaging device.

9. a database storing pre-acquired computed tomography (CT) imaging data and / or pre-acquired X-ray imaging data of at least the chest wall of the patient; 6. The mechanical ventilation device of claim 5, further comprising:

10. The at least one electronic controller receiving, from an associated mechanical ventilator, at least one of airflow during inspiration of the patient and airflow pressure within the patient's airway during mechanical ventilation therapy; and Calculating the pressure value further based on the airflow and / or the airflow pressure. The mechanical ventilation device of claim 1 , further configured to:

11. further comprising a mechanical ventilator configured to deliver mechanical ventilation to the patient; 11. The mechanical ventilation device of claim 10, wherein the mechanical ventilator is configured to measure at least one of airflow during inspiration of the patient and airflow pressure within the patient's airway during mechanical ventilation therapy.

12. The mechanical ventilator includes a display device, and the at least one electronic controller controlling a display device to display a pressure-volume curve of the patient's lungs during mechanical ventilation; and when the calculated pressure value is outside the range of values ​​defined by the displayed pressure-volume curve; outputting said warning; and and outputting recommended adjustments to one or more parameters of mechanical ventilation therapy delivered to the patient. Do at least one of the following: The mechanical ventilation device of claim 11 further configured to:

13. The at least one electronic controller calculating from the received imaging data a pretension value of the patient's lungs at the end of expiration when there is no activity by the patient's respiratory muscles; and calculating the pressure value further based on the calculated pretension value.

2. The mechanical ventilation device of claim 1, further configured to calculate the pressure value by:

14. The at least one electronic controller 12. The mechanical ventilation device of claim 11, configured to control the ventilator to adjust one or more parameters of mechanical ventilation therapy delivered to the patient based on the calculated pressure value.

15. Using at least one electronic controller, receiving imaging data relating to dimensions of a patient's diaphragm during inspiration and expiration while the patient is undergoing mechanical ventilation therapy with an associated mechanical ventilator; calculating a pressure value in the patient's chest based at least on the imaging data; When the calculated pressure value does not meet the acceptance criteria, outputting a warning indicating that the calculated pressure value does not meet the acceptance criteria; and outputting recommended adjustments to one or more parameters of the mechanical ventilation therapy delivered to the patient. and performing at least one of the steps of: A mechanical ventilation method having:

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