CN119423735A

CN119423735A - Respiratory signal reliability determination method, device and storage medium

Info

Publication number: CN119423735A
Application number: CN202310955932.0A
Authority: CN
Inventors: 李尔松; 徐桂丹; 李恒; 王祺; 帕努·塔卡拉
Original assignee: GE Precision Healthcare LLC
Current assignee: GE Precision Healthcare LLC
Priority date: 2023-08-01
Filing date: 2023-08-01
Publication date: 2025-02-14

Abstract

The embodiments of the present application provide a method, device and storage medium for judging the reliability of a breathing signal. The method comprises: calculating a first signal quality based on a first breathing signal from a first signal source, wherein the first breathing signal is a physiological signal characterizing the breathing state of a user; calculating a second signal quality based on a second signal from at least one second signal source different from the first signal source, wherein the second signal is a physiological signal different from the first breathing signal, and judging the reliability of the first breathing signal based on the second signal quality and the first signal quality. Thus, the reliability of the breathing signal of the breathing signal source is verified by the signal of a physiological signal source different from the breathing signal source, thereby achieving accurate monitoring and reducing the triggering of false apnea alarms.

Description

Respiratory signal reliability judging method, device and storage medium

Technical Field

The embodiment of the application relates to the technical field of medical equipment, in particular to a respiratory signal reliability judging method, a respiratory signal reliability judging device and a storage medium.

Background

A respiration monitoring apparatus is an apparatus that monitors the respiration state of a monitored subject.

In general, an impedance type respiration rate detection method is used for monitoring, which is based on the principle that a human body has conductivity, and a measurement area is equivalent to a resistor, and the impedance of the measurement area changes along with respiratory motion, so that the respiration state is monitored by measuring the impedance change. For example, electrode sheets are attached to both sides of the chest of a patient, and a high-frequency constant current source is applied. When the patient breathes, the chest cavity is driven to expand and contract, the resistance between the electrode plates can change along with the chest cavity, so that a breathing signal waveform is obtained by detecting the impedance change, and information such as the breathing rate is calculated according to the breathing signal waveform, so that whether the breathing state of the patient is normal or not is monitored.

It should be noted that the foregoing description of the background art is only for the purpose of providing a clear and complete description of the technical solution of the present application and is presented for the convenience of understanding by those skilled in the art.

Disclosure of Invention

The breathing modes are divided into chest breathing, abdomen breathing and chest-abdomen breathing, the chest and abdomen expansion and contraction amplitudes under different breathing modes are different, and the amplitude of the impedance change is influenced accordingly, so that the size of the electrode signal is influenced by the breathing modes, and the monitoring of the breathing state is influenced. For example, assuming that the respiratory state of the patient is normal and the respiratory mode of the patient is abdominal respiration, respiratory monitoring is performed by using respiratory signals acquired by chest electrodes, and due to small chest impedance changes under abdominal respiration, the acquired respiratory signals are weak, which may trigger a false alarm of apnea.

Aiming at least one of the technical problems, the embodiment of the application provides a breathing signal reliability judging method, a device and a storage medium.

According to a first aspect of an embodiment of the present application, there is provided a respiratory signal reliability determination method, the method including:

Calculating a first signal quality from a first respiration signal from a first signal source, the first respiration signal being a physiological signal representative of a respiration state of the user;

Calculating a second signal quality from a second signal from at least one second signal source different from the first signal source, the second signal being a physiological signal different from the first respiratory signal, and

And judging the reliability of the first respiratory signal according to the second signal quality and the first signal quality.

According to a second aspect of an embodiment of the present application, there is provided a respiratory signal reliability determination apparatus, the apparatus including:

A processor performing the steps of the method as described for performing the embodiments of the first aspect.

According to a third aspect of embodiments of the present application, there is provided a non-transitory computer readable storage medium for storing a computer program which, when executed by a computer, causes the computer to perform the method of the embodiments of the first aspect.

The embodiment of the application has the beneficial effects that the reliability of the breathing signal source is verified through the signal of the physiological signal source different from the breathing signal source, so that accurate monitoring is realized, and the triggering of the pseudo-alarm of the apnea is reduced.

Specific implementations of embodiments of the application are disclosed in detail below with reference to the following description and drawings, indicating the manner in which the principles of embodiments of the application may be employed. It should be understood that the embodiments of the application are not limited in scope thereby. The embodiments of the application include many variations, modifications and equivalents within the spirit and scope of the appended claims.

Drawings

The accompanying drawings, which are included to provide a further understanding of embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is evident that the drawings in the following description are only examples of the application and that other embodiments can be obtained from these drawings by a person skilled in the art without inventive effort. In the drawings:

Fig. 1 is a schematic diagram of an embodiment of a respiratory signal reliability determining method according to the present application.

Fig. 2 is a schematic diagram of another embodiment of a respiratory signal reliability determining method according to an embodiment of the present application.

Fig. 3 is a schematic diagram of a pulse wave signal according to an embodiment of the application.

Fig. 4 is a schematic diagram of the pulse wave signal shown in fig. 3 after signal processing.

Fig. 5 is a schematic diagram of a second respiration signal obtained based on the pulse wave signal shown in fig. 3.

Fig. 6 is a schematic diagram of an electrocardiogram signal according to an embodiment of the present application.

Fig. 7 is a QRS wave extracted from the electrocardiogram signal shown in fig. 6.

Fig. 8 is a schematic diagram of a second respiration signal obtained based on the electrocardiogram signal shown in fig. 6.

Fig. 9 is a flowchart of a respiratory signal reliability determination method according to an embodiment of the application.

FIG. 10 is a waveform diagram illustrating a method of an embodiment of the present application.

Fig. 11 is another waveform diagram for verifying a method of an embodiment of the present application.

Fig. 12 is yet another waveform diagram for verifying a method of an embodiment of the present application.

Fig. 13 is a schematic diagram of a respiratory signal reliability determining apparatus according to an embodiment of the application.

Detailed Description

The foregoing and other features of embodiments of the application will be apparent from the following description, taken in conjunction with the accompanying drawings. In the specification and drawings, there have been specifically disclosed specific embodiments of the application that are indicative of some of the ways in which the principles of the embodiments of the application may be employed, it being understood that the application is not limited to the specific embodiments described, but, on the contrary, the embodiments of the application include all modifications, variations and equivalents falling within the scope of the appended claims.

In the embodiments of the present application, the terms "first," "second," and the like are used to distinguish between different elements from each other by name, but do not indicate spatial arrangement or time sequence of the elements, and the elements should not be limited by the terms. The term "and/or" includes any and all combinations of one or more of the associated listed terms. The terms "comprises," "comprising," "including," "having," and the like, are intended to reference the presence of stated features, elements, components, or groups of components, but do not preclude the presence or addition of one or more other features, elements, components, or groups of components.

In embodiments of the present application, the singular forms "a," an, "and" the "include plural referents and should be construed broadly to mean" one "or" one type "and not limited to" one "or" another; furthermore, the term "comprising" is to be interpreted as including both the singular and the plural, unless the context clearly dictates otherwise. Furthermore, the term "according to" should be understood as "based at least in part on" the term "based on" should be understood as "based at least in part on" the term "unless the context clearly indicates otherwise.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments in combination with or instead of the features of the other embodiments. The term "comprises/comprising" when used herein refers to the presence of a feature, integer, step or component, but does not exclude the presence or addition of one or more other features, integers, steps or components.

The embodiment of the application provides a respiratory signal reliability judging method. Fig. 1 is a schematic diagram of an embodiment of a respiratory signal reliability determining method according to the present application.

As shown in fig. 1, the method 100 includes:

102 calculating a second signal quality from a second signal from at least one second signal source different from the first signal source, the second signal being a physiological signal different from the first respiratory signal, and

And 103, judging the reliability of the first respiration signal according to the second signal quality and the first signal quality.

Thus, the reliability of the respiratory signal source is judged by the signal of the physiological signal source different from the respiratory signal source, so that the triggering of the apnea false alarm is reduced.

In operation 101, the first signal source is, for example, a respiration monitoring device, and the first respiration signal is, for example, a respiration signal acquired through an abdomen electrode or a chest electrode, which is sometimes referred to as an "impedance RESP waveform". In addition, the first signal quality of the first respiratory signal is not limited in the embodiment of the present application, for example, the first signal quality is the amplitude and/or respiratory rate of the first respiratory signal.

In operation 102, the second signal source is a monitoring device different from the respiration monitoring device, such as an electrocardiogram monitoring device. In addition, the second signal is, for example, a physiological signal related to the breathing state of the user, for example, at least one of a pulse wave signal and an electrocardiogram signal.

The inventors have found that the vagus nerve, sympathetic nerve and other pressure sensor systems near the aortic arch are all affected during breathing. The nervous system will then adjust the interval between systoles during breathing to ensure stability of blood pressure. In addition, the lungs squeeze the heart, affecting the ejection of the heart, affecting the pulse wave slope (ejection velocity) and pulse wave amplitude (ejection intensity). Chest breathing and abdominal breathing have this effect. Thus, an Electrocardiogram (ECG) wave and a pulse wave contain information reflecting the breathing state, and a breathing waveform (i.e., a RESP waveform) can be obtained by detecting an R-R interval of the ECG wave, detecting an envelope of the pulse wave, or interpolating, for example.

Thus, the reliability of the respiratory signal can be verified by using other physiological signals related to the respiratory state, and the generation of an apnea false alarm can be reduced.

The related contents of the second signal will be described in detail below.

As shown in fig. 2, the method 200 includes:

calculating a second respiration signal from signals of the second signals related to the respiration state of the user 201;

And 202, switching the first respiratory signal to the second respiratory signal when the first respiratory signal is judged to be unreliable.

In operation 201, the second respiratory signal is a signal extracted from the second signal. For example, since the respiratory state of the user affects the change of physiological parameters such as heart rate and pulse, the respiratory state information is included in the electrocardiographic wave signal and the pulse wave signal, and a signal related to the respiratory state can be extracted by performing signal processing on the electrocardiographic wave signal and the pulse wave signal.

The method of extracting the second respiratory signal from the second signal will be described below by taking the pulse wave signal and the electrocardiographic wave signal as examples, respectively. However, the embodiment of the present application is not limited thereto, and the second signal may be other physiological signals affected by respiratory motion.

In at least one embodiment, the second signal is a pulse wave signal. In addition, the method of acquiring the pulse wave signal in the embodiment of the present application is not limited, and may be, for example, a photoelectric pulse waveform obtained by non-invasive blood pressure detection, or a pulse waveform obtained by invasive blood pressure detection.

Fig. 3 is a schematic diagram of a pulse wave signal according to an embodiment of the present application, wherein (a) is an original pulse wave signal, (b) is a filtered pulse wave signal obtained by high-pass filtering the original pulse wave signal, fig. 4 is a schematic diagram of a pulse wave signal shown in fig. 3 after signal processing, wherein (a) is a slope waveform, (b) is an amplitude waveform, and fig. 5 is a schematic diagram of a second respiration signal obtained based on the pulse wave signal shown in fig. 3.

In at least one embodiment, the pulse wave signal is subjected to a high-pass filtering process to obtain a filtered pulse wave signal.

As shown in fig. 3, the original pulse wave signal (as shown in fig. 3 (a)) contains a large amount of low-frequency drift interference and high-frequency noise, and the respiration signal is a low-frequency signal, so that the high-pass filtering of the pulse wave signal can remove the low-frequency interference, and the accuracy of extracting the respiration signal is improved (as shown in fig. 3 (b)). In addition, the pulse wave signal can be subjected to curve fitting to remove low-frequency interference.

In at least one embodiment, a slope envelope and/or an amplitude envelope of the filtered pulse wave signal is extracted.

For example, the filtered pulse wave signal shown in fig. 3 (b) is subjected to differential processing to obtain a slope curve of the signal, a slope envelope is extracted from the slope curve as shown in fig. 4 (a), and an amplitude envelope is extracted from the filtered pulse wave signal shown in fig. 3 (b) as shown in fig. 4 (b).

Embodiments of the present application are not limited to the implementation of extracting the slope envelope or the amplitude envelope, and specific implementations may refer to the related art.

In addition, when the waveform of the respiration state is extracted based on the pulse wave signal, the extraction of the amplitude envelope is more convenient and quicker, namely, the peak point and the trough point of the pulse wave are usually separated by half a pulse wave period, and the change of the respiration waveform can be recorded by detecting the peak and the trough of the pulse wave. However, the inventor finds that, because the peak point and the trough point of the pulse wave are far apart and are easily affected by low-frequency interference, by detecting the envelope of the slope of the pulse wave, not only the change of the ejection intensity caused by the heart extrusion by the lung in the respiratory process can be reflected, but also the change of the ejection velocity can be reflected, and the peak point and the trough point of the slope of the pulse wave are closer, the drying resistance is stronger, the fluctuation of the heart ejection along with the respiratory cycle can be reflected more accurately, and thus the respiratory waveform can be extracted more accurately.

In at least one embodiment, the second respiratory signal is derived from the slope envelope and/or the amplitude envelope.

For example, the slope envelope and the amplitude envelope are weighted, the peak-to-valley points are interpolated, and resampled to obtain a second respiration signal (sometimes referred to as a "pulse RESP waveform"), e.g., to obtain the second respiration signal 502 shown in fig. 5.

In at least one embodiment, in operation 102, the second signal quality may be calculated from at least one of an amplitude of the second respiratory signal, a ratio of signal energy in a first frequency range to total energy in the second respiratory signal, a ratio of a second frequency range centered on a main frequency to total frequency range in the second respiratory signal, and a statistic of pulse intervals of the pulse wave signal.

The amplitude of the second respiration signal is, for example, an average value of the amplitudes of the second respiration signal.

The first frequency range is, for example, a range of 0.15 Hz-1/3 of the heart rate, such as the heart rate of a subject (e.g., a patient), or may be a statistically derived heart rate, such as a statistically derived normal heart rate range or heart rate median or heart rate average for men/women/children/young/elderly, etc., as the embodiment of the application is not limited in this regard.

The second frequency range is, for example, a predetermined range on both sides of the center frequency obtained by spectral transformation of the second respiratory signal, which is, for example, 1/4 of the heart rate. The second frequency range is not limited by the embodiments of the present application.

The statistics of the pulse intervals of the pulse wave signal are, for example, average differences of the pulse intervals, mean square differences of the pulse intervals, and the like, which are not limited by the embodiment of the present application.

In addition, in some embodiments, the second signal quality may be obtained by performing weighted calculation on an amplitude of the second respiratory signal, a proportion of signal energy in the first frequency range in the second respiratory signal to total energy, a proportion of the second frequency range centered on the main frequency in the second respiratory signal to total frequency range, a statistic of pulse intervals of the pulse wave signal, and the like.

In addition, the first signal quality may also be calculated according to the amplitude, the velocity, the ratio of the frequency around the main frequency to the total frequency range, and the like of the first respiratory signal, which is not limited by the embodiment of the present application.

In operation 103, it is determined whether the first respiratory signal is reliable based on the first signal quality and the second signal quality. For example, comparing the first signal quality to a first threshold, comparing the second signal quality to a second threshold, and determining that the first respiratory signal is unreliable if the first signal quality is below the first threshold and the second signal quality is above the second threshold. The embodiment of the application does not limit the values of the first threshold value and the second threshold value, and can be set according to actual needs.

Therefore, the stability and the reliability of the signal are measured through the signal quality, the reliability of the first respiration signal is judged through the more stable and reliable signal, and the generation of the apnea false alarm caused by the first respiration signal can be reduced.

In addition, in operation 202, in the case where the first respiratory signal is unreliable, the respiratory state of the subject is monitored using the second respiratory signal, for example, the respiratory rate is calculated using the second respiratory signal, or whether there is an apnea condition is monitored using the second respiratory signal, and an alarm is issued when an abnormal respiratory rate or an apnea condition is monitored.

In addition, when the first signal quality is equal to or higher than the first threshold value, the first respiration signal is considered to be reliable, and the detection can be continued using the first respiration signal. In addition, under the condition that the first breathing signal is reliable, whether an apnea condition exists is further judged, and if the apnea condition occurs, an apnea alarm is sent out.

In addition, as shown in fig. 2, the method 200 may further include:

and 203, outputting information representing that the input lead corresponding to the first respiratory signal is not matched with the state of the user when the first respiratory signal is judged to be unreliable.

For example, assuming that the user (e.g., patient) is chest breathing, but the operator (e.g., nurse) has the signal of the abdominal electrode of the monitor connected to the input port of the respiratory monitoring, an alarm of apnea may be triggered due to the weaker signal of the abdominal electrode, but based on this alarm alone it is not possible to confirm whether the wrong input lead was selected or whether the patient's breath is weaker.

According to the embodiment of the application, the unreliable signals of the abdomen electrode can be judged, the prompt information of the wrong lead is output, and an operator can understand that the patient is likely to breathe in chest after seeing the prompt information, so that the correct input lead is reinserted.

For another example, assume that the lead electrode is in poor contact, resulting in a weaker detection signal, triggering an alarm of apnea. By the embodiment of the application, the signal corresponding to the lead electrode can be judged to be unreliable, the prompt message is output, and an operator can be reminded to carefully check whether the contact quantity of the lead electrode exists.

In at least one embodiment, the second signal is an electrocardiogram signal. In addition, the electrocardiographic signals in the embodiment of the present application may be acquired by, for example, a single-lead mode or a multi-lead mode, and the embodiment of the present application does not limit the acquisition mode. Thus, the source signal of the RESP signal may be obtained from the limb or a single electrocardiogram lead.

Fig. 6 is a schematic diagram of an electrocardiogram signal according to an embodiment of the present application, fig. 7 is a QRS wave extracted from the electrocardiogram signal shown in fig. 6, and fig. 8 is a schematic diagram of a second respiration signal obtained based on the electrocardiogram signal shown in fig. 6.

In at least one embodiment, the RR interval and QT interval of the electrocardiogram signal are extracted.

RR interval refers to the interval between R waves on an electrocardiogram from time to time. Typically, each big grid of the electrocardiograph drawing represents 0.2 seconds, the normal RR interval takes 3-5 big grids, namely 0.6-1.0 seconds, representing the time of one cardiac cycle. The number of RR intervals occurring in one minute is the heart rate, and the RR intervals can be calculated through the heart rate, the calculation method is that 60 is divided by the heart rate, and the heart rate of a normal person is 60-100 times per minute. For example, as shown in fig. 6, the RR interval is 587ms, 576ms, 518ms, or the like, for example.

QT interval refers to the interval from the start of the QRS complex to the end of the T wave, representing the time required for the ventricular muscle depolarization and repolarization process. The QT interval length is closely related to the heart rate, and the faster the heart rate, the shorter the QT interval, and vice versa. Whereas the normal range of heart rate is 60-100 beats/minute, the normal range for the corresponding QT interval is 0.32-0.44 seconds. For example, as shown in fig. 7, the QT interval is 178ms, 190ms, 187ms, or the like, for example.

For example, all RR intervals and QT intervals in the predetermined time window may be extracted from the electrocardiogram signal in the predetermined time window, and signal processing may be performed according to the RR waveform corresponding to the RR intervals and the QT waveform corresponding to the QT intervals to obtain waveforms of the corresponding respiratory signals. The embodiment of the application does not limit the implementation of extracting the RR interval and the QT interval, and can refer to the related technology.

In at least one embodiment, the second respiratory signal is derived from the RR interval and the QT interval.

For example, the RR interval and QT interval are weighted, interpolated and resampled to obtain a waveform of the second respiration signal (sometimes also referred to as an "ECG-RESP waveform"), e.g., to obtain the second respiration signal 802 shown in fig. 8.

In at least one embodiment, in operation 102, the second signal quality may be calculated based on at least one of the presence or absence of arrhythmia, an amplitude of the second respiratory signal, a signal-to-noise ratio of the electrocardiogram signal, a signal proportion of a third frequency range centered at a dominant frequency in the second respiratory signal, and a statistic of the RR interval.

For example, it may be determined whether an arrhythmia is present based on the second signal. For example, whether arrhythmia exists may be determined according to RR interval and/or QT interval, and the embodiment of the present application does not limit a specific determination method, and may refer to the related art.

The signal-to-noise ratio of the electrocardiogram signal may be, for example, the signal-to-noise ratio of R-waves in the electrocardiogram signal.

The third frequency range is, for example, a predetermined range on both sides of the center frequency obtained by spectral transformation of the second respiratory signal, which is, for example, 1/4 of the heart rate. The third frequency range is not limited by the embodiments of the present application.

The statistics of RR intervals are, for example, average difference of RR intervals, etc., which is not limited by the embodiment of the present application.

Additionally, the method of an embodiment of the present application may further comprise calculating a respiration rate from the first respiration signal and/or the second respiration signal. For example, fig. 5 shows a first respiration signal 501, fig. 8 shows a first respiration signal 801, the first respiration signal 501 or the first respiration signal 801 being for example an impedance RESP waveform, the respiration rate (RESP rate) may be calculated from the first respiration signal 501 or the first respiration signal 801 only, the respiration rate may be calculated from the second respiration signal 502 or the second respiration signal 802 only, and the respiration rate may be calculated from the first respiration signal 501/the first respiration signal 801 and the second respiration signal 502/the second respiration signal 802. Implementations of calculating the respiration rate may refer to the related art, to which embodiments of the present application are not limited. In addition, after the respiration rate is calculated, the display device may be controlled to display the respiration rate.

The method for judging whether the respiratory signal is reliable or not by the signal quality of the electrocardiogram signal is similar to the method for judging whether the respiratory signal is reliable or not by the signal quality of the pulse wave signal, and will not be described in detail here.

In addition, the method according to the embodiment of the present application may further include, if the first respiratory signal is determined to be unreliable, performing respiratory status monitoring according to the second respiratory signals corresponding to the plurality of second signal sources, for example, performing weighted calculation on respiratory rates corresponding to the plurality of second respiratory signals as a monitoring parameter.

Fig. 9 is a flowchart of a respiratory signal reliability determination method according to an embodiment of the application. The respiratory signal reliability determination method according to the embodiment of the present application will be further described with reference to fig. 9. It should be noted that the following description is for the purpose of making the implementation of the embodiments of the present application clearer, and should not be construed as limiting the embodiments of the present application.

As shown in fig. 9, the respiratory signal reliability determination method 900 includes:

901, obtaining an impedance RESP waveform;

902, performing signal processing on the impedance RESP waveform, for example, performing digital signal processing;

903, calculating a corresponding respiration rate-1 according to the impedance RESP waveform after signal processing;

904, acquiring pulse waveforms;

905 signal processing the pulse waveform, for example, digital signal processing;

906 extracting a pulse wave envelope, e.g., an amplitude envelope, from the signal-processed pulse waveform;

907 extracting slope envelope from the pulse waveform after signal processing;

908, obtaining a pulse RESP waveform corresponding to the pulse waveform according to the amplitude envelope and/or the slope envelope;

909 calculating the corresponding respiration rate-2 from the pulse RESP waveform;

910, calculating the quality of pulse RESP waveform;

911 acquiring an ECG waveform;

912, signal processing the ECG waveform, e.g., digital signal processing;

913 extracting the R-R interval and the QT interval from the ECG waveform after signal processing;

914, obtaining an ECG-RESP waveform corresponding to the ECG waveform according to the R-R interval and the QT interval, for example, performing signal processing such as weighting, interpolation, resampling and the like on the RR signal corresponding to the extracted R-R interval and the QT signal corresponding to the QT interval to obtain the ECG-RESP waveform;

915, calculating a corresponding respiration rate-3 from the ECG-RESP waveform;

calculating the quality of the ECG-RESP waveform 916;

917, judging whether the amplitude of the respiration rate-1 and impedance RESP waveform is low and the quality of the pulse RESP waveform P or ECG-RESP waveform is high, if yes, operation 918 is entered, and if no, operation 919 is entered;

918 switching a monitoring source of respiration status (e.g., respiration rate), informing the relevant personnel that a lead of impedance RESP monitoring needs to be replaced;

919 continuing to monitor the respiratory state of the patient using the impedance RESP.

Therefore, a RESP monitoring source can be increased, and the reliability of RESP detection is improved.

In addition, in operation 918, the source signal of the RESP signal may be switched from the impedance RESP waveform to the pulse RESP waveform, or the source signal showing the respiration rate may be switched from respiration rate-1 to respiration rate-2.

In addition, the impedance RESP waveform, the pulse RESP waveform, and the ECG waveform may mutually verify, that is, if the respiration rate of one of the waveforms is low, the respiration rates of the other two waveforms may be checked, if the respiration waveforms and the respiration rates of the other two waveforms are normal, an apnea alarm may not be prompted, and additionally, an input signal monitoring the respiration state may be switched to at least one of the two waveforms. Thus, the most stable source can be automatically found from the electrocardiogram, pulse wave and impedance RESP waveform to be used as the RESP source.

In addition, for the method of the embodiments of the present application, the inventors have validated using a public physiological signal database. Fig. 10 to 12 are waveform diagrams for verifying a method according to an embodiment of the present application.

The "The Beth Israle Deconess MEDICAL CENTRE (BIDMC) PPG and Respiration" data set contains a ppg pulse waveform and an impedance RESP waveform, and after the RESP waveform is analyzed from the pulse wave, the impedance RESP waveform may be weak for the 15 th, 21 st, and 53 th signals, and the RESP rate may not be obtained from the impedance RESP wave, but the pulse RESP waveform is good, and the RESP rate may be obtained from the pulse RESP wave. For example, as shown in fig. 10, the signal 1001 is an impedance RESP waveform, the signal 1002 is a pulse RESP waveform, and during the second half of the signal, the impedance RESP waveform is weak, but the pulse RESP waveform extracted by the pulse waveform is still good. This means that the pulse RESP waveform extracted by the pulse wave signal has higher stability.

For the MIT-BIH electrocardiographic aberration database, the sampling rate is 360Hz, as shown in FIG. 12, FIG. 12 is a schematic diagram of R-R interval analysis of an ECG signal, as shown in FIG. 13, and FIG. 13 is an ECG-RESP waveform extracted from the ECG signal.

Through verification, the method provided by the embodiment of the application can reliably obtain a stable RESP source.

In addition, by the method of the embodiment of the application, a RESP source is added, and new accessories or hardware are not required to be added. And if the user is not connected with the electrocardiogram lead, the RESP rate can be obtained from the photoelectric blood oxygen pulse wave, so that the operation of monitoring the respiratory rate is simplified, and the medical staff can grasp the physiological state of the patient more conveniently and rapidly.

The embodiment of the application also provides a respiratory signal reliability judging device, and fig. 13 is a schematic diagram of the respiratory signal reliability judging device according to the embodiment of the application.

As shown in fig. 13, the respiratory signal reliability determination device 1300 includes a processor 1301, and the processor 1301 performs the steps of the respiratory signal reliability determination method described in the foregoing embodiments.

In at least one embodiment, as shown in fig. 13, the respiratory signal reliability determination apparatus 1300 may further include a first signal source 1302 and a second signal source 1303.

The first signal source 1302 outputs the first respiration signal according to the previous embodiment according to the first input signal, and the first signal source 1302 is, for example, a respiration monitoring device.

The second signal source 1303 outputs the second signal described in the foregoing embodiment according to the second input signal. The number of the second signal sources 1303 may be 1 or more, for example, as shown in fig. 13, including a second signal source 1303-1 and a second signal source 1303-2, where the second signal source 1303-1 is, for example, an electrocardiogram monitoring device, and the second signal source 1303-2 is, for example, a pulse oxygen saturation monitoring device.

In at least one embodiment, the processor 1301 may be a processing apparatus that is relatively independent of the first signal source 1302 and the second signal source 1303, for example, the processor 1301 may be a central processor of the respiratory signal reliability determining apparatus 1300, and the signals acquired by the respective signal sources are all sent to the processor 1301, where the processing of the steps of the method of the foregoing embodiment is performed in the processor 1301. The processor 1301 may be a processing unit disposed in the first signal source 1302 and/or the second signal source 1303, for example, each signal source may process a signal to obtain a respiration waveform, and then input the obtained respiration waveform to a processing unit of a certain signal source for subsequent processing, or may input the obtained respiration waveform to a central processing unit of the respiration signal reliability determination apparatus 1300 for subsequent processing. The embodiments of the present application are not limited in this regard.

In addition, the respiratory signal reliability determination device 1300 may further include other components, such as a display device. The respiratory signal reliability determination device 1300 may also be configured as a medical system with other devices such as a display device, for example, an electrocardiograph monitor. The embodiments of the present application are not limited in this regard.

The embodiment of the present application also provides a computer readable program, wherein when the program is executed, the program causes a computer to execute the respiratory signal reliability determination method described in the foregoing embodiment in a respiratory signal reliability determination device.

The embodiment of the present application also provides a non-transitory computer readable storage medium for storing a computer program, which when executed by a computer, causes the computer to execute the respiratory signal reliability determination method described in the foregoing embodiment.

The above embodiments have been described only by way of example of the embodiments of the present application, but the present application is not limited thereto, and appropriate modifications may be made on the basis of the above embodiments. For example, each of the above embodiments may be used alone, or one or more of the above embodiments may be combined.

While the application has been described in connection with specific embodiments, it will be apparent to those skilled in the art that the description is intended to be illustrative and not limiting in scope. Various modifications and alterations of this application will occur to those skilled in the art in light of the spirit and principles of this application, and such modifications and alterations are also within the scope of this application.

Preferred embodiments of the present application are described above with reference to the accompanying drawings. The many features and advantages of the embodiments are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the embodiments which fall within the true spirit and scope thereof. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the application to the exact construction and operation illustrated and described, and accordingly, all suitable modifications, variations and equivalents that fall within the scope thereof may be resorted to.

Claims

1. A method for determining the reliability of a respiratory signal, characterized in that the method comprises:

Calculating a first signal quality according to a first breathing signal from a first signal source, wherein the first breathing signal is a physiological signal representing a breathing state of a user;

calculating a second signal quality based on a second signal from at least one second signal source different from the first signal source, the second signal being a physiological signal different from the first respiratory signal, and

The reliability of the first breathing signal is determined according to the second signal quality and the first signal quality.

2. The method according to claim 1 is characterized in that the second signal is a physiological signal related to the user's breathing state.

3. The method according to claim 2, characterized in that the method further comprises:

Calculating a second breathing signal according to a signal related to the user's breathing state in the second signal;

When it is determined that the first respiration signal is unreliable, the first respiration signal is switched to the second respiration signal.

4. The method according to claim 1, wherein determining the reliability of the first breathing signal comprises:

comparing the first signal quality with a first threshold;

comparing the second signal quality with a second threshold;

When the first signal quality is lower than the first threshold and the second signal quality is higher than the second threshold, it is determined that the first breathing signal is unreliable.

5. The method according to claim 1, characterized in that the method further comprises:

When it is determined that the first breathing signal is unreliable, information indicating that the input wire corresponding to the first breathing signal is not compatible with the state of the user is output.

6. The method according to any one of claims 1 to 5, characterized in that

The second signal is at least one of a pulse wave signal and an electrocardiogram signal.

7. The method according to claim 3, wherein the second signal is a pulse wave signal, and the method further comprises:

Performing high-pass filtering on the pulse wave signal to obtain a filtered pulse wave signal; and

A slope envelope and/or an amplitude envelope of the filtered pulse wave signal is extracted.

8. The method according to claim 7, characterized in that

In the step of calculating the second breathing signal, the second breathing signal is obtained according to the slope envelope and/or the amplitude envelope.

9. The method according to claim 8, characterized in that

In the step of calculating the second signal quality,

The second signal quality is calculated based on at least one of the amplitude of the second breathing signal, the proportion of signal energy in the first frequency range of the second breathing signal to the total energy, the proportion of the second frequency range centered on the main frequency in the second breathing signal to the total frequency range, and the statistic of the pulse interval of the pulse wave signal.

10. The method according to claim 3, wherein the second signal is an electrocardiogram signal, and the method further comprises:

extracting the RR interval and the QT interval of the electrocardiogram signal, and

The second respiratory signal is obtained according to the RR interval and the QT interval.

11. The method according to claim 10, characterized in that the method further comprises:

judging whether there is arrhythmia according to the second signal,

In the step of calculating the second signal quality,

The second signal quality is calculated based on at least one of whether there is arrhythmia, the amplitude of the second respiratory signal, the signal-to-noise ratio of the electrocardiogram signal, the signal proportion of a third frequency range centered on the main frequency in the second respiratory signal, and the statistics of the RR interval.

12. A device for determining the reliability of a respiratory signal, characterized in that the device comprises:

A processor, which performs the steps of the method according to any one of claims 1 to 11.

13. The breathing signal reliability determination device according to claim 12, characterized in that the breathing signal reliability determination device further comprises:

A first signal source, which outputs a first breathing signal according to a first input signal;

At least one second signal source outputs a second signal according to a second input signal.

14. The breathing signal reliability determination device according to claim 13, characterized in that:

The processor is configured at the first signal source and/or the at least one second signal source.

15. A non-transitory computer-readable storage medium for storing a computer program, wherein when the computer program is executed by a computer, the computer executes the method according to any one of claims 1 to 11.