A respiration and metabolic oxygen consumption measuring device and method

Abstract

This invention discloses a device and method for measuring respiratory and metabolic oxygen consumption, comprising: an experimental chamber, an air intake assembly, and a differential pressure sensor; the experimental chamber contains adsorbent material for absorbing water and carbon dioxide; the air intake assembly includes a resistance valve, one end of which is connected to the experimental chamber via a second pipe, and the other end is connected to the atmosphere or a normal pressure gas storage bladder; the positive pressure interface of the differential pressure sensor is connected to the experimental chamber via a first pipe, and the negative pressure interface is connected to the atmosphere; the differential pressure sensor is used to collect air pressure changes within the experimental chamber, and respiratory data of the test subject is obtained based on the air pressure changes, including respiratory rate and / or pulmonary ventilation. This invention can calculate respiratory data such as respiratory rate and pulmonary energy changes of the test subject without an oxygen sensor, and is used for measuring metabolic oxygen consumption, thereby improving the service life of the equipment and reducing costs.

Description

Technical Field

[0001] This application relates to a respiratory measurement device, specifically to a device and method for measuring respiratory and metabolic oxygen consumption. Background Technology

[0002] Hypoxia experiments are a fundamental teaching experiment commonly conducted in courses such as pathophysiology and human functional science. By observing the physiological and behavioral changes in animals such as mice and rats under hypoxic conditions, the effects of different types of hypoxia on the body can be understood, aiming to provide a basis for the treatment and research of hypoxia-related diseases. Traditional hypoxia experiments typically employ methods such as wide-mouth bottle observation, endotracheal intubation, and xiphoid process recording. These methods either cannot quantitatively monitor respiratory movements in mice and rats, or require anesthesia or invasive procedures, and none of them can quantitatively monitor metabolic oxygen consumption in real time, thus exhibiting numerous methodological shortcomings.

[0003] In recent years, quantitative monitoring devices for hypoxia experiments in awake mice and rats have been commercialized. These devices primarily use oxygen sensors for detection, but oxygen sensors are expensive and have a short lifespan (usually less than two years). Therefore, due to limitations in equipment price and the price and lifespan of oxygen sensors, the cost of using such devices for teaching experiments is too high, hindering their widespread adoption in educational settings. Thus, improving the lifespan and reducing the price of quantitative monitoring devices for hypoxia experiments has become a crucial technical challenge for their widespread adoption. Summary of the Invention

[0004] In view of the above problems, this application provides a respiratory and metabolic oxygen consumption measuring device to solve the technical problems of low detection accuracy, short service life and high price of the existing devices.

[0005] To achieve the above objectives, the inventors provide a device for measuring respiratory and metabolic oxygen consumption, comprising:

[0006] The experimental chamber is a sealed chamber used to contain the test object, and it contains adsorbent material to absorb the water and carbon dioxide generated by the test object during the measurement process.

[0007] An air intake assembly, including a resistance valve, has one end connected to the experimental chamber via a second pipe, and the other end connected to the atmosphere or to an atmospheric pressure storage bladder. The atmospheric pressure storage bladder stores oxygen or other gases and maintains its internal pressure at the same level as the atmosphere. The resistance valve is connected in series in the air intake path of the air intake assembly.

[0008] The differential pressure sensor includes a positive pressure interface and a negative pressure interface. The positive pressure interface is connected to the experimental chamber through a first pipe, and the negative pressure interface is connected to the atmosphere. The differential pressure sensor is used to collect the air pressure changes in the experimental chamber and obtain the respiratory data of the test subject based on the air pressure changes. The respiratory data includes respiratory rate and / or lung ventilation.

[0009] The resistance valve is used to increase the flow resistance between the experimental chamber and the atmosphere or the atmospheric pressure storage bladder, so that the pressure change collected by the differential pressure sensor maps the change in lung ventilation of the test subject.

[0010] Furthermore, the air intake assembly also includes an air extraction device and a gate valve;

[0011] The selector valve and the resistance valve are connected in series, and the air extraction device is connected to the selector valve. The selector valve is used to select whether the air extraction device is connected to the experimental chamber or to the atmospheric pressure storage bladder or the atmosphere, so as to extract a predetermined amount of gas or a predetermined amount of atmosphere from the atmospheric pressure storage bladder into the experimental chamber. The selector valve is also used to close the air intake component after the predetermined amount of atmosphere or gas is extracted, and to collect the time required for the pressure decay of a set amount in the experimental chamber or the amount of pressure decay within a set time through the differential pressure sensor, and to calculate the metabolic oxygen consumption of the test object.

[0012] Furthermore, the selector valve is a stopcock three-way valve or a solenoid three-way valve. The selector valve includes at least three connection ends. The first connection end is connected to the experimental chamber through the second pipe, the second connection end is connected to the air extraction device, and the third connection end is connected to the atmosphere or connected to the atmospheric pressure storage bladder.

[0013] Furthermore, the air extraction device is a piston syringe or a syringe pump.

[0014] Furthermore, the resistance valve is an adjustable resistance valve assembly, comprising a resistance valve body with fixed resistance and a rotary regulating valve connected in series with the resistance valve body and having adjustable conduction resistance; the rotary regulating valve is a throttle valve or a pressure regulating valve.

[0015] Furthermore, the experimental chamber includes a bottle-shaped chamber with an opening and a sealing plug adapted to the opening; the first pipe and the second pipe extend into the chamber through the sealing plug;

[0016] The adsorbent material is sodium lime granules or a mixture of sodium lime granules and color-changing silica gel granules, and the adsorbent material is spread flat on the bottom of the chamber to form an adsorption layer.

[0017] Furthermore, the end of the second pipe that connects to the sealing plug is flush with the bottom surface of the sealing plug;

[0018] The first pipe extends into one end of the cabin and is inserted into the shallow area of ​​the adsorption layer.

[0019] Furthermore, the portion of the first pipe extending into the cabin is eccentrically positioned within the cabin.

[0020] To address the aforementioned technical problems, this application also provides another technical solution:

[0021] A method for measuring respiratory and metabolic oxygen consumption includes the following steps:

[0022] An adsorbent material and a test object are placed inside the experimental chamber. The adsorbent material is used to absorb the water and carbon dioxide generated by the test object during the measurement process.

[0023] The experimental chamber is connected to a differential pressure sensor and an air intake assembly. The differential pressure sensor includes a positive pressure interface and a negative pressure interface. The positive pressure interface is connected to the experimental chamber via a first pipe, and the negative pressure interface is connected to the atmosphere. The air intake assembly includes a resistance valve. One end of the air intake assembly is connected to the experimental chamber via a second pipe, and the other end is connected to the atmosphere or to an atmospheric pressure reservoir. The atmospheric pressure reservoir stores oxygen or other gases, and maintains its internal pressure at the same level as the atmosphere. The resistance valve is connected in series in the air intake path of the air intake assembly. The resistance valve increases the flow resistance of gas in the air intake path, so that the pressure change collected by the differential pressure sensor reflects the change in lung ventilation of the test subject.

[0024] The differential pressure sensor collects the air pressure changes in the experimental chamber caused by the breathing of the test subject, and the breathing data of the test subject is obtained based on the air pressure changes. The breathing data includes respiratory rate and / or pulmonary ventilation.

[0025] Furthermore, it also includes the following steps:

[0026] A predetermined amount of gas or a predetermined amount of air is drawn from the atmospheric pressure storage bladder into the experimental chamber, and then the air intake assembly is closed to seal the experimental chamber.

[0027] The differential pressure sensor collects the time required for a set amount of air pressure to decay in the experimental chamber, or the amount of air pressure decay within a set time, and calculates the metabolic oxygen consumption of the test subject.

[0028] Unlike existing technologies, the above-mentioned technical solution does not use expensive and easily damaged oxygen sensors. Instead, it uses a combination of differential pressure sensors and resistance valves to detect the change in relative air pressure difference between the experimental chamber and the outside atmospheric pressure. Based on Boyle's law and the ideal gas law pV=nRT, it calculates respiratory data such as the respiratory rate and lung energy changes of the test subject.

[0029] In some embodiments, since the water and carbon dioxide in the experimental chamber are absorbed by the adsorbent material, the change in the pressure difference is positively correlated with the change in oxygen in the experimental chamber; when the experimental chamber is sealed, the oxygen consumption of the test object can be monitored in real time by the change in the pressure difference.

[0030] The above description of the invention is merely an overview of the technical solution of this application. In order to enable those skilled in the art to better understand the technical solution of this application and to implement it based on the description and drawings, and to make the above-mentioned objectives and other objectives, features and advantages of this application easier to understand, the following description is provided in conjunction with the specific embodiments and drawings of this application. Attached Figure Description

[0031] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of specific embodiments of the present invention and other related contents, and should not be considered as limitations on this application.

[0032] In the accompanying drawings of the instruction manual:

[0033] Figure 1 This is a schematic diagram of the respiratory and metabolic oxygen consumption measuring device described in a specific embodiment;

[0034] Figure 2a This is a schematic diagram of the experimental chamber, the first pipe, and the second pipe as described in the specific implementation method;

[0035] Figure 2b This is a schematic diagram of the structure of the experimental chamber described in another specific embodiment;

[0036] Figure 3 This is a schematic diagram of the adjustable resistance valve described in a specific embodiment;

[0037] Figure 4 The respiratory data of the detection object collected by the differential pressure sensor described in the specific implementation embodiment;

[0038] Figure 5 A flowchart illustrating the method for measuring respiratory and metabolic oxygen consumption as described in the specific implementation embodiment;

[0039] The reference numerals used in the above figures are explained as follows:

[0040] 1. Experimental chamber; 11. Chamber body; 12. Sealing plug; 13. Second pipe; 14. First pipe; 15. Gas injection channel; 16. Valve;

[0041] 2. Differential pressure sensor; 21. Positive pressure interface; 22. Negative pressure interface;

[0042] 3. Intake assembly; 31. Selective valve; 32. Resistance valve; 33. Air extraction device; 321. Resistance valve body; 322. Rotary regulating valve;

[0043] 4. Atmospheric pressure air reservoir;

[0044] 5. Data acquisition device;

[0045] 6. Monitor;

[0046] 7. Adsorbed materials; Detailed Implementation

[0047] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.

[0048] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0049] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0050] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.

[0051] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.

[0052] Without further limitations, the use of terms such as “comprising,” “including,” “having,” or other similar open-ended expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0053] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0054] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0055] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0056] Please see Figure 1 This embodiment provides a device for measuring respiratory and metabolic oxygen consumption. This device can be used to measure respiratory data such as oxygen consumption and respiratory rate in various test subjects, including mice and rats, and can also be used to conduct hypoxia experiments on these subjects.

[0057] like Figure 1 As shown, in this embodiment, the respiratory and metabolic oxygen consumption measuring device includes: experimental chamber 1, differential pressure sensor 2, and air intake assembly 3.

[0058] The experimental chamber 1 is a sealed chamber 11 used to contain the test object and contains adsorbent material 7 to absorb water and carbon dioxide generated by the test object during the measurement process. The experimental chamber 1 has an opening through which the test object can be placed and removed. The size of the experimental chamber 1 can be determined according to the size and number of test objects. In some embodiments, the experimental chamber 1 includes a bottle-shaped chamber 11 with an opening and a sealing plug 12 adapted to the opening; the adsorbent material 7 is soda lime granules, but it is not limited to soda lime granules. Specifically, in one embodiment, the experimental chamber 1 is a 250mL gas washing bottle as the chamber 11, and the gas washing bottle is equipped with a sealing plug 12. Soda lime granules are filled into the lower part of the bottle up to the 50mL mark to absorb carbon dioxide and water generated by respiration. In some embodiments, the adsorbent material 7 can also be a mixture of soda lime granules and color-changing silica gel granules, wherein the color-changing silica gel granules can be used to absorb water vapor in the experimental chamber 1, and the soda lime granules mainly absorb carbon dioxide in the experimental chamber 1. In some embodiments, the adsorbent material 7 may be only soda lime particles, while in other embodiments, in order to have good water absorption and carbon dioxide absorption effects, the adsorbent material 7 may also be a mixture of soda lime particles and color-changing silica gel particles.

[0059] The air intake assembly 3 includes a resistance valve 32. One end of the air intake assembly 3 is connected to the experimental chamber 1 via a second pipe 13, and the other end is connected to the atmosphere or to an atmospheric pressure storage bladder 4. The atmospheric pressure storage bladder 4 stores oxygen or other gases, and maintains its internal pressure at the same level as the atmosphere. The resistance valve 32 is connected in series in the air intake path of the air intake assembly 3. The atmospheric pressure storage bladder 4 can be homemade using a plastic bag or a thin-walled rubber bladder.

[0060] The air intake assembly 3 connects the experimental chamber 1 to the atmosphere or atmospheric pressure gas storage bladder 4. When the air intake assembly 3 is open, gas from the atmosphere or atmospheric pressure gas storage bladder 4 can enter the experimental chamber 1 (when the air intake assembly 3 is closed, the experimental chamber 1 forms a sealed space, preventing gas from entering or leaving). It should be noted that the air intake assembly 3 does not restrict the gas flow to only the outside of the experimental chamber 1. When the air intake assembly 3 is open, gas will enter and exit the experimental chamber 1 through the air intake assembly 3 according to the breathing frequency of the subject breathing inside the experimental chamber 1.

[0061] The differential pressure sensor 2 includes a positive pressure interface 21 and a negative pressure interface 22. The positive pressure interface 21 is connected to the experimental chamber 1 through a first pipe 14, and the negative pressure interface 22 is connected to the atmosphere. The differential pressure sensor 2 is used to collect the air pressure changes in the experimental chamber 1 and obtain the respiratory data of the test subject based on the air pressure changes. The respiratory data includes respiratory rate and / or lung ventilation.

[0062] The differential pressure sensor 2 has a negative pressure interface 22 that is connected to the outside atmosphere. Using the atmospheric pressure outside the experimental chamber 1 as a reference, it calculates the pressure difference between the gas pressure inside the experimental chamber 1 and the atmospheric pressure. The differential pressure sensor 2 is connected to the data acquisition unit 5, which is connected to a display 6. Therefore, the data collected by the differential pressure sensor 2 can be displayed on the display 6 via the data acquisition unit 5.

[0063] The resistance valve 32 is used to increase the flow resistance of gas in the air intake path, that is, to increase the flow resistance of gas exchange between the experimental chamber and the atmosphere or the atmospheric pressure storage bladder, so that the air intake assembly 3 can divert the air pressure fluctuations in the experimental chamber 1 caused by the breathing of the test subject, so that the air pressure change collected by the differential pressure sensor 2 can be mapped to the change in the lung ventilation of the test subject.

[0064] In this embodiment, the end of the first pipe 14 connected to the experimental chamber 1 is completely sealed by the differential pressure sensor 2, and the resistance valve 32 connected to the second pipe 13 generates a certain resistance to the gas flow, thus also having a certain sealing effect on the experimental chamber 1.

[0065] When the experimental chamber 1 is completely sealed, the internal temperature T remains stable, the sum of the external space volume and lung volume of the test subject (e.g., mouse or rat) V is a constant, and the total amount of gas inside and outside the test subject in the experimental chamber 1 n is a constant, according to Boyle's law and the ideal gas law pV = nRT, the air pressure measured by the differential pressure sensor 2 at the end of inspiration and the end of respiration is equal (baseline air pressure value). During inspiration, the chest and abdomen of the test subject expand outward, the external space volume of the test subject decreases and the air pressure increases, the lung volume of the test subject increases and the intrapulmonary pressure decreases. Driven by the pressure difference, gas enters the lungs. Due to the limited expansion of the thoracic cavity and lungs, as gas enters the lungs, the intrapulmonary pressure gradually changes from decreasing to increasing, while the external space air pressure changes from increasing to decreasing, until the external space air pressure and the intrapulmonary pressure are equal again, and inspiration ends. Specifically, during the inspiratory phase, the external air pressure of the test subject initially rises from the baseline level, reaches a certain maximum, and then decreases until it returns to the baseline level; this is the positive phase wave of the inspiratory phase. The expiratory phase, on the other hand, exhibits the opposite negative phase wave. By acquiring the air pressure signal within the experimental chamber 1 using differential pressure sensor 2, the respiratory rate data of the test subject can be obtained in real time. Integrating the positive or negative phase wave of the air pressure fluctuation over the duration t of inspiration or expiration yields an area value representing the change in lung ventilation of the test subject. However, it should be noted that when there are significant volume differences between individual test subjects, this area value can only be used for comparison within the same individual before and after intervention.

[0066] Because the subjects continuously consume oxygen through respiration within experimental chamber 1, and the carbon dioxide and water produced by respiration are absorbed by soda lime, the amount of gaseous matter n inside the chamber will continuously decrease. Even if the respiratory rate and depth of the subjects remain unchanged, the waveforms of the positive and negative phase waves of respiration collected by differential pressure sensor 2 will continuously change, making it unusable for evaluating changes in lung ventilation. Therefore, in this embodiment, a resistance valve (preferably an adjustable resistance valve assembly) with a pipe resistance much greater than the airway resistance of mice is designed and connected to the atmosphere or a normal pressure airbag. The pressure difference between the inside and outside of the chamber caused by oxygen consumption can drive outside air or gas from the normal pressure airbag to continuously enter experimental chamber 1 through resistance valve 32, maintaining the stability of the amount of gaseous matter n inside the chamber. When the resistance of resistance valve 32 is sufficiently high, it has only a weak diversion effect on the pressure fluctuations caused by the respiration of the subjects. At this time, the respiratory curve collected by differential pressure sensor 2 can be used to analyze changes in lung ventilation in mice.

[0067] In the above embodiment, the respiratory and metabolic oxygen consumption measuring device does not use an expensive and easily damaged oxygen sensor. Instead, it employs a combination of a differential pressure sensor 2 and a resistance valve 32 to detect the change in the relative pressure difference between the experimental chamber 1 and the external atmospheric pressure. Based on Boyle's law and the ideal gas law pV = nRT, it calculates respiratory data such as the respiratory rate and lung energy changes of the tested subject. This significantly improves the service life of the respiratory and metabolic oxygen consumption measuring device and reduces its production and subsequent maintenance costs.

[0068] like Figure 1 As shown, in one embodiment, the air intake assembly 3 further includes an air extraction device 33 and a selector valve 31. The air extraction device 33 can be a manual piston syringe or an electric syringe pump. The syringe pump is connected to a power source and a control switch, which enables the syringe pump to operate, thereby extracting gas from the atmosphere or atmospheric pressure gas storage bladder 4 into the experimental chamber 1. The selector valve 31 controls whether the experimental chamber 1 is connected to the air extraction device 33 via the second pipe 13 or to the atmosphere or atmospheric pressure gas storage bladder 4. In some embodiments, the selector valve 31 is a stopcock three-way valve or a solenoid three-way valve, and the selector valve 31 includes at least three connection ends: the first connection end is connected to the experimental chamber 1 via the second pipe 13; the second connection end is connected to the air extraction device 33; and the third connection end is connected to the atmosphere or to the atmospheric pressure gas storage bladder 4.

[0069] The selector valve 31 and the resistance valve 32 are connected in series. The air extraction device 33 is connected to the selector valve 31. The selector valve 31 is used to select whether the air extraction device 33 is connected to the experimental chamber 1 or to the atmospheric pressure storage bladder 4 or the atmosphere, so as to extract a predetermined amount of gas or a predetermined amount of atmosphere from the atmospheric pressure storage bladder 4 into the experimental chamber 1. The selector valve 31 is also used to close the air intake component 3 after the predetermined amount of atmosphere or gas is extracted, and to collect the time required for the pressure decay of a set amount in the experimental chamber 1 or the amount of pressure decay within a set time through the differential pressure sensor 2, and to calculate the metabolic oxygen consumption of the test object.

[0070] When the air intake assembly 3 also includes an air extraction device 33 and a selector valve 31, the respiratory and metabolic oxygen consumption measuring device can be used for real-time monitoring of oxygen consumption. A certain amount (e.g., 1 mL) of air or oxygen can be drawn into the experimental chamber 1 through the air intake assembly 3, and then the experimental chamber 1 is sealed for oxygen consumption monitoring.

[0071] For example, in one embodiment, the stopcock tee on the infusion tubing is selected as the aforementioned gate valve 31, and a 2mL syringe is selected as the aforementioned air extraction device 33. Then, the oxygen consumption is measured using the gas injection pressure measurement method. A certain volume of air or oxygen is accurately extracted using a 2mL disposable syringe according to experimental needs and connected to the infusion stopcock tee. When measuring oxygen consumption, the stopcock tee is rotated so that the experimental chamber 1 is only connected to the disposable syringe, and the gas in the disposable syringe is immediately injected into the experimental chamber 1. The air pressure inside the chamber increases, and the baseline of the respiratory curve recorded by the differential pressure sensor 2 immediately rises to a certain level. The mouse breathes in the experimental chamber 1, continuously consuming oxygen. The exhaled carbon dioxide and water are absorbed by soda lime, and the air pressure inside the chamber gradually decreases. When the air pressure returns to atmospheric pressure, the stopcock tee is rotated again to keep the experimental chamber 1 connected to the resistance valve, and the respiratory curve continues to be recorded. The time required for the baseline of the respiratory curve to recover from its highest value to atmospheric pressure level after gas injection was measured using a respiratory and metabolic oxygen consumption measuring device. The oxygen consumption rate of mice was quantified by dividing the injected gas volume by the pressure recovery time, expressed in mL·g⁻¹·h⁻¹. Alternatively, the change in the oxygen consumption rate of mice can be qualitatively analyzed by observing the change in the slope of the respiratory curve baseline.

[0072] like Figure 2a As shown, in one embodiment, the experimental chamber 1 includes a bottle-shaped chamber 11 with an opening and a sealing plug 12 adapted to the opening; the first pipe 14 and the second pipe 13 extend into the chamber 11 through the sealing plug 12; the adsorbent material 7 is sodium lime granules, which are spread flat on the bottom of the chamber 11 to form an adsorption layer. One end of the second pipe 13 connected to the sealing plug 12 is flush with the bottom surface of the sealing plug 12; one end of the first pipe 14 extends into the chamber 11 and is inserted into the shallow area of ​​the adsorption layer.

[0073] In this embodiment, the first pipe 14 is inserted into the shallow area of ​​the adsorption layer, and the second pipe 13 is flush with the bottom surface of the sealing plug 12. This prevents the test subject (e.g., a mouse) inside the chamber from approaching the openings of the first pipe 14 and the second pipe 13, thereby avoiding deviations in the test data caused by the movement of the test subject and ensuring the accuracy and reliability of the respiratory and metabolic oxygen consumption measuring device. Furthermore, in one embodiment, to prevent the test subject from moving around the first pipe 14 inside the experimental chamber 1, the portion of the first pipe 14 extending into the chamber body 11 is offset within the chamber body 11. Since the movement of the test subject changes its cardiopulmonary exertion and can alter the temperature inside the experimental chamber 1, both of which affect the measurement results, this embodiment offsets the first pipe 14 within the chamber body 11 to prevent the test subject from moving around it, ensuring the accuracy and reliability of the respiratory and metabolic oxygen consumption measuring device.

[0074] like Figure 2bAs shown, in one embodiment, the experimental chamber 1 is further provided with an injection channel 15 and a valve 16, wherein the valve 16 is connected in series with the injection channel 15. When the valve 16 is open, carbon monoxide, nitric oxide, and other gases required for the breathing experiment can be injected into the experimental chamber 1 through the injection channel 15. Preferably, the diameter of the injection channel 15 and / or the chamber volume of the valve 16 should be set relatively small (e.g., the inner diameter of the injection channel 15 is less than 1 mm) to ensure good airtightness of the injection channel 15 and the valve 16. At the same time, the switching between the open and closed states of the valve 16 will not have a significant impact on the internal air pressure of the experimental chamber 1.

[0075] In this embodiment, when the experimental chamber 1 includes a bottle and a sealing plug 12, the gas injection channel 15 is disposed on the sealing plug 12. When it is necessary to inject gas into the experimental chamber for experimental projects, such as studying the effects of carbon monoxide, nitric oxide, etc. on respiration, the valve 16 can be opened and the experimental gas can be injected into the experimental chamber 1 through the gas injection channel 15, and then the valve 16 can be closed.

[0076] like Figure 3 As shown, in one embodiment, the resistance valve 32 is an adjustable resistance valve assembly, including a resistance valve body 321 with fixed resistance and a rotary regulating valve 322 connected in series with the resistance valve body 321, which allows for adjustable conduction resistance. The rotary regulating valve 322 can be a throttle valve or a pressure regulating valve. By rotating the knob on the throttle valve or pressure regulating valve, the internal conduction area of ​​the throttle valve or pressure regulating valve can be adjusted, thereby adjusting the conduction resistance of the throttle valve or pressure regulating valve. Preferably, the rotary regulating valve 322 is a miniature throttle valve or a miniature pressure regulating valve.

[0077] In this embodiment, the resistance valve 32 is an adjustable resistance valve assembly. Therefore, the resistance of the air intake assembly 3 can be adjusted according to the individual size or number of the test objects, making the respiratory and metabolic oxygen consumption measuring device applicable to a variety of different types of test objects and improving its flexibility of use.

[0078] like Figure 4 The image shows the respiratory data of the test subject collected by the differential pressure sensor 2 in the above embodiment. Part A contains waveform data of oxygen consumption measured 10 times consecutively while the test subject is awake and 10 times consecutively while the test subject is anesthetized. Part B contains respiratory rate data of the test subject mapped from the pressure changes within the experimental chamber 1 collected by the differential pressure sensor 2.

[0079] like Figure 5 As shown, in one embodiment, a method for measuring respiratory and metabolic oxygen consumption is provided, which should include the following steps:

[0080] S501. Place adsorbent material and test object in the experimental chamber, wherein the adsorbent material is used to absorb water and carbon dioxide generated by the test object during the measurement process;

[0081] S502. The experimental chamber is connected to a differential pressure sensor and an air intake assembly. The differential pressure sensor includes a positive pressure interface and a negative pressure interface. The positive pressure interface is connected to the experimental chamber through a first pipe, and the negative pressure interface is connected to the atmosphere. The air intake assembly includes a resistance valve. One end of the air intake assembly is connected to the experimental chamber through a second pipe, and the other end of the air intake assembly is connected to the atmosphere or to an atmospheric pressure storage bladder. The atmospheric pressure storage bladder stores oxygen or other gases, and the internal pressure of the atmospheric pressure storage bladder is kept at the same pressure as the atmosphere. The resistance valve is connected in series in the air intake path of the air intake assembly. The resistance valve is used to increase the flow resistance of gas in the air intake path, so that the air intake assembly can divert the air pressure fluctuations in the experimental chamber caused by the breathing of the test subject, so that the air pressure change collected by the differential pressure sensor can be mapped to the change in the lung ventilation of the test subject.

[0082] S503. The differential pressure sensor collects the air pressure changes in the experimental chamber caused by the breathing of the test subject, and obtains the breathing data of the test subject based on the air pressure changes. The breathing data includes respiratory rate and / or lung ventilation.

[0083] In one embodiment, the above-described method for measuring respiratory and metabolic oxygen consumption further includes the step of:

[0084] A predetermined amount of gas or a predetermined amount of air is drawn from the atmospheric pressure storage bladder into the experimental chamber, and then the air intake assembly is closed to seal the experimental chamber.

[0085] The differential pressure sensor collects the time required for a set amount of air pressure to decay in the experimental chamber, or the amount of air pressure decay within a set time, and calculates the metabolic oxygen consumption of the test subject.

[0086] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.

Claims

1. A device for measuring respiratory and metabolic oxygen consumption, characterized in that, include: The experimental chamber is a sealed chamber used to contain the test object, and it contains adsorbent material to absorb the water and carbon dioxide generated by the test object during the measurement process. The adsorbent material is spread flat on the bottom of the chamber to form an adsorption layer. An air intake assembly, including a resistance valve, has one end connected to the experimental chamber via a second pipe, and the other end connected to the atmosphere or to an atmospheric pressure storage bladder. The atmospheric pressure storage bladder stores oxygen or other gases and maintains its internal pressure at the same level as the atmosphere. The resistance valve is connected in series in the air intake path of the air intake assembly. A differential pressure sensor includes a positive pressure interface and a negative pressure interface. The positive pressure interface is connected to the experimental chamber through a first pipe, and the negative pressure interface is connected to the atmosphere. The first pipe extends into one end of the chamber and is inserted into the shallow area of ​​the adsorption layer. The differential pressure sensor is used to collect the air pressure changes in the experimental chamber and obtain the respiratory data of the test subject based on the air pressure changes. The respiratory data includes respiratory rate and / or lung ventilation. The resistance valve is used to increase the flow resistance between the experimental chamber and the atmosphere or the atmospheric pressure storage bladder, so that the pressure change collected by the differential pressure sensor maps the change in lung ventilation of the test subject.

2. The respiratory and metabolic oxygen consumption measuring device according to claim 1, characterized in that, The air intake assembly also includes an air extraction device and a gate valve; The selector valve and the resistance valve are connected in series, and the air extraction device is connected to the selector valve. The selector valve is used to select whether the air extraction device is connected to the experimental chamber or to the atmospheric pressure storage bladder or the atmosphere, so as to extract a predetermined amount of gas or a predetermined amount of atmosphere from the atmospheric pressure storage bladder into the experimental chamber. The selector valve is also used to close the air intake component after the predetermined amount of atmosphere or gas is extracted, and to collect the time required for the pressure decay of a set amount in the experimental chamber or the amount of pressure decay within a set time through the differential pressure sensor, and to calculate the metabolic oxygen consumption of the test object.

3. The respiratory and metabolic oxygen consumption measuring device according to claim 2, characterized in that, The selector valve is a stopcock three-way valve or a solenoid three-way valve. The selector valve includes at least three connection ends. The first connection end is connected to the experimental chamber through the second pipe. The second connection end is connected to the air extraction device. The third connection end is connected to the atmosphere or to the atmospheric pressure storage bladder.

4. The apparatus for measuring respiratory and metabolic oxygen consumption according to claim 2, characterized in that, The air extraction device is a piston syringe or a syringe pump.

5. The apparatus for measuring respiratory and metabolic oxygen consumption according to claim 1, characterized in that, The resistance valve includes a resistance valve body with fixed resistance and a rotary regulating valve connected in series with the resistance valve body and having adjustable conduction resistance; the rotary regulating valve is a throttle valve or a pressure regulating valve.

6. The apparatus for measuring respiratory and metabolic oxygen consumption according to claim 1, characterized in that, The experimental chamber includes a bottle-shaped chamber with an opening and a sealing plug adapted to the opening; the first pipe and the second pipe extend into the chamber through the sealing plug; The adsorbent material is sodium lime granules or a mixture of sodium lime granules and color-changing silica gel granules.

7. The apparatus for measuring respiratory and metabolic oxygen consumption according to claim 6, characterized in that, The end of the second pipe that connects to the sealing plug is flush with the bottom surface of the sealing plug.

8. The apparatus for measuring respiratory and metabolic oxygen consumption according to claim 6, characterized in that, The portion of the first pipe extending into the cabin is eccentrically positioned within the cabin.

9. A method for measuring respiratory and metabolic oxygen consumption, characterized in that, Includes the following steps: An adsorbent material and a test object are placed inside the experimental chamber. The adsorbent material is used to absorb the water and carbon dioxide generated by the test object during the measurement process. The adsorbent material is spread flat on the bottom of the chamber to form an adsorption layer. The experimental chamber is connected to a differential pressure sensor and an air intake assembly. The differential pressure sensor includes a positive pressure interface and a negative pressure interface. The positive pressure interface is connected to the experimental chamber via a first pipe, and the negative pressure interface is connected to the atmosphere. The first pipe extends into one end of the chamber and is inserted into the shallow area of ​​the adsorption layer. The air intake assembly includes a resistance valve. One end of the air intake assembly is connected to the experimental chamber via a second pipe, and the other end is connected to the atmosphere or to an atmospheric pressure storage bladder. The atmospheric pressure storage bladder stores oxygen or other gases, and maintains its internal pressure at the same level as the atmosphere. The resistance valve is connected in series in the air intake path of the air intake assembly. The resistance valve increases the flow resistance of gas in the air intake path, so that the pressure change collected by the differential pressure sensor reflects the change in lung ventilation of the test subject. The differential pressure sensor collects the air pressure changes in the experimental chamber caused by the breathing of the test subject, and the breathing data of the test subject is obtained based on the air pressure changes. The breathing data includes respiratory rate and / or pulmonary ventilation.

10. The method for measuring respiratory and metabolic oxygen consumption according to claim 9, characterized in that, It also includes the following steps: A predetermined amount of gas or a predetermined amount of air is drawn from the atmospheric pressure storage bladder into the experimental chamber, and then the air intake assembly is closed to seal the experimental chamber. The differential pressure sensor collects the time required for a set amount of air pressure to decay in the experimental chamber, or the amount of air pressure decay within a set time, and calculates the metabolic oxygen consumption of the test subject.

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