Detection device and breathing pressure-sensitive plethysmograph

Abstract

The utility model discloses a detection device and a respiratory pressure-sensitive plethysmograph, and is applied to the field of medical detection. The detection device comprises a telescopic air pipe and an air pressure sensor connected to the telescopic air pipe, the detection device is provided with a closed cavity, and the closed cavity comprises the telescopic air pipe and an inner cavity of the air pressure sensor; the telescopic air pipe surrounds the chest or the abdomen in a detection state, and the air pressure sensor is used for detecting an air pressure signal reflecting the cross sectional area of the chest or the abdomen. The respiratory pressure-sensitive plethysmograph comprises a detection device used for detecting chest signals and a detection device used for detecting abdomen signals. According to the detection device, the inductance coil is replaced by the telescopic air pipe and the air pressure sensor, compared with a sinusoidal inductance coil, the telescopic air pipe is simpler in manufacturing process, and the air pressure sensor is easy to obtain. Therefore, the detection device provided by the utility model is easy to manufacture, and the production efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the field of medical detection, and in particular to a detection device and a respiratory pressure-sensing plethysmograph. Background Art

[0002] In some scenarios, it is necessary to measure the volume of gas entering and leaving the lungs. For example, in some clinical applications (e.g., respiratory muscle strength training), it is necessary to evaluate tidal volume and identify whether the dominant breathing mode of the subject (e.g., patient) is chest breathing or abdominal breathing. If a flow sensor (e.g., a spirometer or pneumotachometer) is used to measure the volume of gas entering and leaving the lungs, there are the following disadvantages: (1) a nasal mask, mouthpiece, or nose clip is required, causing tension, anxiety, and discomfort in the patient; (2) it increases airway resistance, changes the breathing pattern, causes increased ventilation and decreased respiratory rate, and cannot reflect the subject's true breathing capacity; (3) it is impossible to identify the dominant breathing mode.

[0003] Respiratory induction plethysmography (RIP) technology is a method of calculating lung ventilation function through surface respiratory movement. Specifically, after completing a one-time calibration, each time a chest belt and abdominal belt are used to obtain changes in chest and abdominal respiratory volumes, data such as tidal volume and chest-abdominal respiratory contribution ratio can be obtained. RIP technology has the advantages of non-invasive and non-invasive measurement of ventilation volume, can obtain ventilation indicators and quantitatively analyze breathing patterns, and the use process will not cause patient tension, there is less respiratory dead space, and the breathing pattern will not be changed.

[0004] The inductor coil in the respiratory inductance plethysmograph used in the conventional RIP solution needs to be wound into a sinusoidal shape, and the manufacturing process is relatively complicated. Therefore, it is currently desired to provide a detection device for respiratory detection that is easy to manufacture. Utility Model Content

[0005] The purpose of this application is to provide a detection device for respiratory sensing that is easy to manufacture.

[0006] A first aspect of an embodiment of the present application provides a detection device. The detection device includes a retractable trachea and an air pressure sensor connected to the retractable trachea. The detection device has a closed cavity, the closed cavity includes the retractable trachea and the inner cavity of the air pressure sensor, the retractable trachea surrounds the chest cavity or the abdomen in a detection state, and the air pressure sensor is used to detect an air pressure signal reflecting the cross-sectional area of ​​the chest cavity or the cross-sectional area of ​​the abdomen.

[0007] In some embodiments, the detection device also includes two ends and a connecting pipeline, wherein the retractable air tube is connected between the two ends, the connecting pipeline is connected between any end and the air pressure sensor, and the closed cavity also includes the inner cavity of the two ends and the connecting pipeline.

[0008] In some embodiments, at least one end has an opening, and the detection device further includes a plug embedded in the opening of the at least one end.

[0009] In some embodiments, the detection device further comprises two ends, wherein the retractable air tube is connected between the two ends, and the air pressure sensor is installed at either end.

[0010] In some embodiments, the detection device further comprises two ends and two straps that can be bound to each other, wherein the retractable air tube is connected between the two ends, and each strap is connected to one end.

[0011] In some embodiments, the two ends are the same shape and size.

[0012] In some embodiments, the telescopic air tube is detachably connected between the two ends.

[0013] In some embodiments, the strap is detachably connected to the end portion.

[0014] In some embodiments, the telescopic air tube is a bellows.

[0015] The second aspect of the embodiment of the present application provides a respiratory pressure plethysmograph. The respiratory pressure plethysmograph comprises: a detection device for detecting an air pressure signal reflecting the cross-sectional area of ​​the thoracic cavity; and a detection device for detecting an air pressure signal reflecting the cross-sectional area of ​​the abdomen.

[0016] The technical solution provided by the embodiment of the present application has the following advantages over the prior art: the inductor coil is replaced by a retractable air tube and an air pressure sensor, the retractable air tube has a simpler manufacturing process than the sinusoidal inductor coil, and the air pressure sensor is also easy to obtain. Therefore, the detection device provided by the embodiment of the present application is easy to manufacture, which is conducive to improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] This specification will be further described in the form of exemplary embodiments, which will be described in detail by the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein:

[0018] Figure 1 It is a schematic diagram of the components of a respiratory inductance plethysmograph;

[0019] Figure 2 is a schematic structural diagram of an exemplary detection device provided in an embodiment of the present application;

[0020] Figure 3 The relationship curve between air pressure u and cross-sectional area A is shown;

[0021] Figure 4 It is a schematic diagram of the composition of the respiratory pressure plethysmograph provided in an embodiment of the present application. DETAILED DESCRIPTION

[0022] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the embodiments of the present application will be further described below. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application can also be implemented in other ways different from those described herein. Obviously, the embodiments in the specification are only part of the embodiments of the present application, not all of the embodiments.

[0024] First, the theoretical basis of RIP technology is introduced. In this paper, the terms "capacity" and "volume" are used interchangeably.

[0025] According to the paper by Konno and Mead, the thorax can be viewed as a system of two compartments, each with only one degree of freedom. Therefore, any volume change in the abdomen (ab) must be equal and opposite to a volume change in the rib cage (rc). The paper showed that the volume change is nearly linearly related to the change in the anterior-posterior diameter of the body. When a known amount of air is inhaled and measured with a flow sensor, a volume-motion relationship can be established as the sum of the displacements of the abdomen and rib cage. Therefore, according to this theory, only the change in the cross-sectional area of ​​the abdomen, ΔA, is required. ab and the change in chest cross-sectional area ΔA rc To estimate the change in the volume of gas entering and leaving the lungs ΔV. That is, the expression for the change in the volume of gas entering and leaving the lungs ΔV measured at the mouth and nose can be approximated as:

[0026] ΔV=mΔA rc +nΔA ab (1).

[0027] Where m and n are the conversion coefficients of cross-sectional area to volume.

[0028] The traditional RIP scheme uses the basic principle of electromagnetic induction to measure chest and abdominal respiratory movement. The specific implementation process is: the sensor coil attached to the elastic strap is used as the inductance element of the capacitor three-point resonant circuit. The respiratory movement causes the change of the coil inductance, resulting in the change of the resonant condition of the resonant circuit, which causes the resonance amplitude and resonant frequency to change with the respiratory movement. The detection of respiratory movement can be achieved by adopting the idea of ​​amplitude modulation-detection or frequency modulation-discrimination. Through the two chest and abdominal straps, the chest and abdominal respiratory movement curves can be recorded simultaneously. Since the above scheme uses an inductor coil as a sensor, it measures the change in the volume of the respiratory cavity during lung ventilation. Although there are many factors that affect the change in the coil's self-inductance, Watson et al. have proved that the respiratory induction volume tracing method can accurately measure the change in cross-sectional area. Within a certain range, the output voltage and cross-sectional area are linearly related. Therefore, equation (1) can be rewritten as the relationship between the measured voltage signal and the gas flow rate:

[0029] ΔV=aΔu rc +bΔu ab (2).

[0030] Where a and b are the voltage-to-volume conversion coefficients, respectively.

[0031] like Figure 1 As shown, the respiratory inductance plethysmograph consists of two insulated sinusoidal coils placed inside two lightweight elastic and adhesive bands 2.5 cm (about 1 inch) wide. The transducer bands are placed around the chest below the armpits and around the abdomen at the level of the navel. They are connected to an oscillator and subsequent frequency demodulation equipment to obtain a digital waveform. During inspiration / expiration, the cross-sectional area of ​​the chest and abdomen increases / decreases, which changes the self-inductance of the coils and their oscillation frequency, and the amount of change in cross-sectional area is proportional to the amount of change in the volume of gas entering and leaving the lungs. The frequency demodulation equipment converts this frequency change into a digital waveform, where the amplitude of the waveform is proportional to the volume of gas entering and leaving the lungs.

[0032] Exemplarily, to obtain the conversion coefficient, a least square method may be used.

[0033] From formula (2), it can be deduced that:

[0034]

[0035] set up available

[0036] aY+bX=1 (4).

[0037] During calibration, a set of electrical signals Δu is measured through the inductor coil rc and Δu ab At the same time, the flow sensor measures the volume change of the gas in and out of the lungs, ΔV, and then uses the least squares method to draw a line is the x-axis, is the regression line of the y-axis, so a and b can be obtained to complete the calibration process.

[0038] After that, you only need to wear the coil and detect the electrical signal Δu rc and Δu ab , the volume change of gas in and out of the lungs ΔV can be calculated by formula (2). Furthermore, the tidal volume, respiratory rate, and chest breathing contribution ratio can be calculated based on the waveform. and abdominal breathing contribution ratio

[0039] Figure 2 It is a schematic diagram of the structure of an exemplary detection device provided in an embodiment of the present application.

[0040] refer to Figure 2 The detection device 300 includes a telescopic air tube 310 and an air pressure sensor 320 connected to the telescopic air tube 310. The detection device 300 has a closed cavity, which includes the inner cavity of the telescopic air tube 310 and the air pressure sensor 320. The telescopic air tube 310 surrounds the chest cavity or the abdomen in the detection state (for example, the wearing state), and the air pressure sensor 320 is used to detect an air pressure signal reflecting the cross-sectional area of ​​the chest cavity or the cross-sectional area of ​​the abdomen.

[0041] As the trachea 310 stretches or contracts, the air pressure sensor 320 detects changes in air pressure. The change in air pressure within a certain range can reflect changes in the cross-sectional area of ​​the chest or abdomen. Figure 3 ,The experimental results show that the linearity of the relationship between the air pressure value (denoted as u) detected by the air pressure sensor 320 and the cross-sectional area of ​​the chest cavity or abdomen (denoted as A) is very high. Figure 3 The R-square (coefficient of determination) for the set of data points is 0.4474 and the RMSE (standard deviation) is 1.061.

[0042] The detection device provided in the embodiment of the present application replaces the inductor coil with a retractable air tube and an air pressure sensor. The retractable air tube has a simpler manufacturing process than the sinusoidal inductor coil. For example, the air tube can be made by opening a mold by injection molding or the like. The air pressure sensor is also easy to obtain. Therefore, the detection device provided in the embodiment of the present application is easy to manufacture, which is conducive to improving production efficiency.

[0043] In some embodiments, the telescopic air tube 310 includes a bellows. Due to its corrugated structure, the bellows has good flexibility and elasticity, and can be used close to the body of patients with different body shapes (for example, chest circumference, waist circumference).

[0044] In some embodiments, the detection device 300 further includes two ends 330 and a connecting pipe 340, wherein the telescopic air tube 310 is connected between the two ends 330, and the connecting pipe 340 is connected to either end 330 (for example, Figure 2 The closed cavity also includes the two ends 330 and the inner cavity of the connecting pipe 340.

[0045] In other embodiments, the connecting pipe 340 may be omitted. For example, the air pressure sensor 320 may be installed at any end 330, and specifically, the air pressure sensor 320 may be fixed to the inner or outer surface of any end 330. For another example, the air pressure sensor 320 may be used as one end of the detection device 300.

[0046] In some embodiments, the detection device 300 further includes two ends 330 and two straps 350 that can be bound to each other, wherein the retractable air tube 310 is connected between the two ends 330, and each strap 350 is connected to one end 330. By providing the straps, the detection device is wearable, which is conducive to improving the user experience. The two straps 350 can be bound to each other in any feasible manner, for example, by buckles, Velcro and other structures.

[0047] In alternative embodiments, one end 330 and / or one strap 350 may be omitted. For example, one strap 350 is directly connected to the telescopic air tube 310, rather than being indirectly connected to the telescopic air tube 310 through one end 330. For another example, one end 330 is designed as a latch, and a strap 350 with a plug is provided at the other end.

[0048] In some embodiments, at least one end 330 has an opening, and the detection device 300 further includes a plug 360 embedded in the opening of the at least one end. Figure 2 In the embodiment, each end 330 is provided with two circular plugs 360. By providing the plugs, the injection and replacement of the gas are facilitated.

[0049] In some embodiments, the telescopic trachea 310 is detachably connected between the two ends 330. In this way, it is convenient to replace the trachea. Specifically, a trachea of ​​a suitable length can be flexibly selected according to the patient's body shape (for example, chest circumference, waist circumference).

[0050] In some embodiments, the strap 350 is detachably connected to the end 330. In this way, it is convenient to replace the strap. Specifically, a strap of a suitable length can be flexibly selected according to the patient's body shape (eg, chest circumference, waist circumference).

[0051] In some embodiments, the two ends 330 have the same shape and size. Each end 300 adopts a modular design, which can further improve the production efficiency of the detection device.

[0052] Figure 4 Schematic diagram of the composition of the respiratory pressure plethysmograph provided in the embodiment of the present application. Figure 4 As shown, the respiratory pressure-sensing plethysmograph 500 includes two detection devices 300 for detecting air pressure signals, one of which is used to detect an air pressure signal reflecting the cross-sectional area of ​​the thoracic cavity, and the other is used to detect an air pressure signal reflecting the cross-sectional area of ​​the abdomen. More details about the detection device 300 can be found in the aforementioned embodiment and will not be repeated here.

[0053] It should be noted that, in this article, relational terms such as "first" and "second" are intended to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusions, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to the process, method, article or device. In the absence of further restrictions, an element defined by the sentence "including a ..." does not exclude the presence of additional identical elements in the process, method, article or device including the element.

[0054] The above is only an embodiment of the present application, and the embodiment enables those skilled in the art to understand and implement the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments described herein, but will conform to the widest scope consistent with the principles and features disclosed herein.

Claims

1. A detection device, characterized in that: The invention comprises a telescopic air tube and an air pressure sensor connected to the telescopic air tube, wherein: The detection device has a closed cavity, and the closed cavity includes the inner cavity of the telescopic air tube and the air pressure sensor; The retractable trachea surrounds the chest cavity or the abdomen in a detection state, and the air pressure sensor is used to detect an air pressure signal reflecting the cross-sectional area of ​​the chest cavity or the cross-sectional area of ​​the abdomen.

2. The detection device according to claim 1, characterized in that It also includes two ends and a connecting pipeline, wherein the retractable air pipe is connected between the two ends, the connecting pipeline is connected between any end and the air pressure sensor, and the closed cavity also includes the inner cavity of the two ends and the connecting pipeline.

3. The detection device according to claim 2, characterized in that: At least one end has an opening, and the detection device further comprises a plug embedded in the opening of the at least one end.

4. The detection device according to claim 1, characterized in that: It also includes two end portions, wherein the telescopic air tube is connected between the two end portions, and the air pressure sensor is installed at either end portion.

5. The detection device according to claim 1, characterized in that: It also includes two ends and two binding straps that can be bound to each other, wherein the telescopic air tube is connected between the two ends, and each binding strap is connected to one end.

6. The detection device according to any one of claims 2 to 5, characterized in that: The two ends are identical in shape and size.

7. The detection device according to any one of claims 2 to 5, characterized in that: The telescopic air tube is detachably connected between the two ends.

8. The detection device according to claim 5, characterized in that: The strap is detachably connected to the end portion.

9. The detection device according to claim 1, characterized in that: The telescopic air pipe is a bellows.

10. A respiratory pressure plethysmograph, characterized in that: include: A detection device according to any one of claims 1 to 9 for detecting an air pressure signal reflecting a cross-sectional area of ​​a thoracic cavity; A detection device according to any one of claims 1 to 9 for detecting an air pressure signal reflecting the cross-sectional area of ​​the abdomen.

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