KR20220069904A - Device, method, and program for predicting hypotension in patients during surgery using non-invasive data - Google Patents

Abstract

Provided is a method for predicting hypotension in patients using deep learning-based non-invasive data. The method for predicting hypotension in a user using deep learning-based non-invasive data according to one aspect of the present invention comprises: obtaining PPG data, electrocardiogram data, and carbon dioxide partial pressure (CO2 capnography) data of the user; preprocessing the PPG data, the electrocardiogram data, and the CO2 partial pressure data; and inputting the preprocessed PPG data, electrocardiogram data, and CO2 partial pressure data into a deep neural network pre-trained through machine learning, and calculating a hypotension prediction value of the user via the deep neural network. The present invention can increase the accuracy and reliability of hypotension prediction.

Description

{Device, method, and program for predicting hypotension in patients during surgery using non-invasive data}

The present invention relates to a device for predicting hypotension in a patient.

If the hypotensive shock that occurred in the patient during the operation of the patient is prolonged, the blood supply to the organs decreases and serious damage such as myocardial infarction, stroke, acute kidney injury, etc. may occur. For hypotensive shock, which can be fatal to the patient, the use of drugs such as anesthetics is limited due to the nature of the operation, and it takes 5-10 minutes or more to prepare the necessary devices or drugs such as vasopressors. If the hypotensive shock state continues, there is a problem that adversely affects the patient's prognosis. In addition, when measuring a patient's blood pressure through a method of measuring the pressure by inserting a tube directly into the patient's artery to predict hypotension, there is a problem in that the patient is at risk of infection due to the inserted tube.

US 2019-0336085

An object of the present invention is to provide a method of increasing the accuracy of predicting hypotension in a patient by using the patient's PPG data, electrocardiogram data, and carbon dioxide partial pressure data together.

In addition, the problem to be solved by the present invention is to provide a method for predicting hypotension in a patient only with non-invasive data obtained by a non-invasive method, except for an invasive method in which the patient has a risk of infection.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Hypotension prediction apparatus according to an embodiment of the present disclosure for solving the above-described problems, a data acquisition unit for acquiring PPG data, electrocardiogram data, and carbon dioxide partial pressure data of a patient undergoing surgery; and a deep learning unit that calculates a hypotension predicted value of the patient by inputting it into a deep neural network based on the acquired PPG data, electrocardiogram data, and carbon dioxide partial pressure data of the patient, wherein the deep learning unit includes the patient's PPG data, electrocardiogram It is characterized in that the probability of occurrence of hypotension in the patient is calculated n minutes after the data and carbon dioxide partial pressure data are acquired.

The data acquisition unit further includes a data processing unit configured to acquire PPG data from a plurality of patients, and to obtain arterial blood pressure data of the plurality of patients by analyzing the acquired PPG data, wherein the data processing unit obtains the obtained arterial blood pressure data. By analyzing the blood pressure data, arterial blood pressure data in which the section in which the mean arterial blood pressure is less than the first reference blood pressure lasts for more than 1 minute is classified as hypotension data, and the section in which the mean arterial blood pressure is greater than or equal to the second reference blood pressure lasts for 20 minutes or more classifying the arterial blood pressure data to be normotensive data, extracting a first section designated in advance from the classified hypotension data and a second section preset from the normotensive data as input data, the deep learning unit comprising: the hypotension data and The result classified as normotensive data is input to the deep neural network as correct answer data, the extracted input data is input to the deep neural network, and the hypotension predicted value of the patient calculated through the deep neural network is the correct answer data characterized in comparison with

In addition, the first section is a section having a predetermined length n minutes before the occurrence of the small section lasting more than 1 minute, and the second section is a large section lasting more than 20 minutes in the normotensive data It is characterized in that it is a section having a predetermined length n minutes before the occurrence time of .

In addition, the data acquisition unit further includes a data processing unit that acquires PPG data from a plurality of patients, and obtains arterial blood pressure data of the plurality of patients by analyzing the acquired PPG data, wherein the hypotension prediction device includes the obtained PPG data. The arterial blood pressure data is analyzed to classify the arterial blood pressure data into hypotensive data and normotensive data, and from the hypotensive data, data of a predetermined first section before the n minutes are extracted as input data, and from the normotensive data It is characterized in that by extracting the data of the second pre-designated section before n minutes as input data, it is used as learning data for predicting whether the patient has hypotension after n minutes.

In addition, the data acquisition unit acquires the patient's biosignal based on the monitoring result of the patient in operation, and acquires the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data based on the acquired biosignal do it with

Hypotension prediction method according to an embodiment of the present disclosure for solving the above-described problems, a method performed by a hypotension prediction apparatus, comprising: acquiring PPG data, electrocardiogram data, and carbon dioxide partial pressure data of a patient undergoing surgery; and calculating a hypotension predicted value of the patient by inputting it into a deep neural network based on the obtained PPG data, electrocardiogram data, and carbon dioxide partial pressure data of the patient, wherein the calculating of the hypotension predicted value includes the patient's PPG data, electrocardiogram It is characterized in that the probability of occurrence of hypotension in the patient is calculated n minutes after the data and carbon dioxide partial pressure data are acquired.

In addition, the hypotension prediction apparatus obtains PPG data from a plurality of patients, obtains arterial blood pressure data of the plurality of patients by analyzing the obtained PPG data, and analyzes the obtained arterial blood pressure data to obtain mean arterial blood pressure Arterial blood pressure data in which a section smaller than the first reference blood pressure lasts for more than 1 minute is classified as hypotensive data, and arterial blood pressure data in which a section in which the mean arterial blood pressure is greater than or equal to the second reference blood pressure lasts for 20 minutes or more is considered normotensive data , extracts a first section designated in advance from the classified hypotension data and a second section preset from the normotensive data as input data, and the results classified into the hypotensive data and the normotensive data are obtained by the deep neural network is input as correct answer data, and the extracted input data is input to the deep neural network, and the patient's hypotension predicted value calculated through the deep neural network is compared with the correct answer data.

In addition, the first section is a section having a predetermined length n minutes before the occurrence of the small section lasting more than 1 minute, and the second section is a large section lasting more than 20 minutes in the normotensive data It is characterized in that it is a section having a predetermined length n minutes before the occurrence time of .

In addition, the hypotension apparatus obtains PPG data from a plurality of patients, analyzes the obtained PPG data to obtain arterial blood pressure data of the plurality of patients, and analyzes the obtained arterial blood pressure data to determine the arterial blood pressure? ? Data is classified into hypotensive data and normotensive data, data of a first pre-designated section n minutes before from the hypotensive data is extracted as input data, and a second pre-designated section before the n minutes from the normo-blood pressure data data is extracted as input data and used as learning data for predicting whether the patient has hypotension after n minutes.

In addition to this, a computer program stored in a computer-readable recording medium for execution for implementing the present disclosure may be further provided.

In addition to this, a computer-readable recording medium recording a computer program for executing a method for implementing the present disclosure may be further provided.

According to the present invention as described above, it has various effects as follows.

The present invention can predict the occurrence of hypotension in a patient by using the information (PPG, ECG, CO2 partial pressure) monitored during surgery as input data of the deep neural network.

In addition, the present invention can predict the occurrence of hypotension in a patient at the current time point or after a predetermined time, and can prepare countermeasures for hypotension in advance, thereby minimizing deterioration of the patient's condition due to prolonged hypotension.

In addition, according to the present invention, the accuracy and reliability of hypotension prediction can be improved by using not only PPG data but also electrocardiogram data and carbon dioxide partial pressure data as input values.

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a block diagram illustrating an apparatus for predicting hypotension in a patient according to an embodiment of the present invention.
2 is a flowchart illustrating a method for predicting hypotension in a patient based on deep learning according to an embodiment of the present invention.
3 is a flowchart illustrating a method of machine learning a deep learning learning model for predicting hypotension according to an embodiment of the present invention.
4 is an exemplary diagram illustrating patient monitoring information according to an embodiment of the present invention.
5 is a block diagram illustrating a method for predicting hypotension in a patient based on deep learning according to an embodiment of the present invention.
6 to 8 are exemplary views for explaining a method of generating learning data according to an embodiment of the present invention.
9 is an exemplary diagram illustrating a deep neural network according to an embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments allow the disclosure of the present invention to be complete, and those of ordinary skill in the art to which the present invention pertains. It is provided to fully understand the scope of the present invention to those skilled in the art, and the present invention is only defined by the scope of the claims.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other components in addition to the stated components. Like reference numerals refer to like elements throughout, and "and/or" includes each and every combination of one or more of the recited elements. Although "first", "second", etc. are used to describe various elements, these elements are not limited by these terms, of course. These terms are only used to distinguish one component from another. Accordingly, it goes without saying that the first component mentioned below may be the second component within the spirit of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used herein will have the meaning commonly understood by those of ordinary skill in the art to which this invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless specifically defined explicitly.

Spatially relative terms "below", "beneath", "lower", "above", "upper", etc. It can be used to easily describe the correlation between a component and other components. Spatially relative terms should be understood as terms including different directions of components during use or operation in addition to the directions shown in the drawings. For example, when a component shown in the drawing is turned over, a component described as “beneath” or “beneath” of another component may be placed “above” of the other component. can Accordingly, the exemplary term “below” may include both directions below and above. Components may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 1 , the apparatus 100 for predicting hypotension according to an embodiment of the present invention may predict hypotension of a patient by using the acquired PPG data, electrocardiogram data, and carbon dioxide partial pressure data. For example, the hypotension prediction apparatus 100 may output a hypotension prediction value using a deep neural network using PPG data, electrocardiogram data, and carbon dioxide partial pressure data as input values, and may predict hypotension of a patient.

In an embodiment, the hypotension prediction apparatus 100 may be a surgery monitoring server, a computer, or a medical device, and a dedicated program for setting a deep learning learning model and a hypotension prediction method may be installed. For example, the hypotension prediction apparatus 100 includes a data acquisition unit 110 capable of acquiring PPG data, electrocardiogram data, and carbon dioxide partial pressure data, a data processing unit 120 capable of pre-processing the acquired data, learning data and deep A deep learning unit 130 that performs machine learning using a neural network and generates a hypotension prediction value, a hypotension determination unit 140 that finally determines whether a patient has hypotension and the current state of the patient through the hypotension prediction value, and learning As a result, it may include a database 150 that can store the structure of the deep neural network, filter values and activation functions, patient data, hypotension prediction values, and the like into big data.

Meanwhile, although not shown in the drawings, the hypotension prediction apparatus 100 may further include an electrocardiogram sensor, a PPG sensor, an EtCO2 sensor, a display for patient monitoring, a sound output device, and the like.

2 is a flowchart illustrating a method for predicting hypotension in a patient based on deep learning according to an embodiment of the present invention. 3 is a flowchart illustrating a method of machine learning a deep learning learning model for predicting hypotension according to an embodiment of the present invention. 4 is a block diagram illustrating a method for predicting hypotension in a patient based on deep learning according to an embodiment of the present invention. 5 is an exemplary diagram illustrating patient monitoring information according to an embodiment of the present invention. 6 to 8 are exemplary views for explaining a method of generating learning data according to an embodiment of the present invention. 9 is an exemplary diagram illustrating a deep neural network according to an embodiment of the present invention.

The operations of FIGS. 2 and 3 may be performed through the apparatus 100 for predicting hypotension of a patient of FIG. 1 .

2 to 9 , in an embodiment, in operation 21 , the data acquisition unit 110 may acquire PPG data, electrocardiogram data, and carbon dioxide partial pressure data of the patient. For example, the data acquisition unit 110 may monitor the patient's body while operating the patient, may acquire the patient's biosignal based on the monitoring result, and may obtain a PPG based on the acquired patient's biosignal. Data, electrocardiogram data, and carbon dioxide partial pressure data may be acquired.

Meanwhile, the data acquisition unit 110 A/D-converts the biosignals (PPG signal, electrocardiogram signal, and carbon dioxide partial pressure signal) acquired from the patient, and as shown in FIG. 4 , PPG data, electrocardiogram data (ECG), and carbon dioxide (CO2) partial pressure data can be obtained. Therefore, the data referred to herein may be a concept including various characteristic values related to the biosignal in addition to the waveform of the biosignal.

For example, the data acquisition unit 110 may receive data from an external device, an input from a user (eg, a medical staff), or an electrocardiogram signal from an electrocardiogram sensor.

For example, the electrocardiogram (ECG) signal is an important signal used for judging diseases of the heart system. is a signal that can be identified.

Although not shown in the drawings, the apparatus 100 for predicting hypotension in a patient may further include an electrocardiogram sensor, and the electrocardiogram sensor includes an electrocardiogram electrode and a reference electrode (or ground electrode), and can detect an electrocardiogram signal. . In some cases, there may be two ECG electrodes. The electrocardiogram sensor may be mounted on a wrist, ankle, chest, upper body, lower body, or the like.

The heartbeat, which is the cause of the electrocardiogram signal, is an impulse that starts from the sinus node located in the right atrium, first depolarizes the right and left atrium and is delayed for a while in the atrioventricular node. then activate the ventricles. The thin-walled right ventricle, with the fastest septum, is activated before the thick-walled left ventricle. The depolarized wave transmitted to the Purkinje Fiber spreads from the endocardium to the epicardium like a wave in the myocardium, causing ventricular contraction. Because electrical impulses are normally conducted through the heart, the heart contracts about 60 to 100 times per minute. Each contraction is represented by one heart rate.

For example, the electrocardiogram signal includes a P wave, a QRS complex, an ST segment, a T wave, and the like. An isoelectric line is a standard line for measuring an electrocardiogram waveform. The space between the equipotential line and the ST segment is called the ST area. An important part to analyze the double ECG signal is the QRS group consisting of Q, R, and S waves. The QRS group is the part where the electrical signal is generated when blood enters and leaves the ventricle from the heart, that is, when the polarization occurs in the ventricle. part that can be checked. The QRS cluster occurs at approximately 0.06 to 0.12 s time. When these waves have a standard shape, the electrical activity of the heart can be considered normal. In order to determine whether each wave has a standard shape or not, it is necessary to check whether characteristics such as the duration of each wave, the interval between each wave, the amplitude of each wave, and the kurtosis are within the normal range.

For example, the electrocardiogram data includes heart rate, QRS period, PR interval, QT interval, type of T wave obtained from the electrocardiogram signal, in addition to the above examples, the time each wave is maintained, the interval between each wave, and each wave. may include characteristic values such as amplitude and kurtosis of .

For example, although not shown in the drawings, the hypotension prediction apparatus 100 may further include a PPG sensor capable of detecting the PPG of the patient. For example, the photoplethysmogram (PPG) uses a periodic change in blood flow in blood vessels as the heart beats. It is measured to estimate the heart rate.

For example, like electrocardiogram data, PPG data may have a waveform corresponding to each unique characteristic, and may include characteristic values such as the time each waveform is maintained, the interval between each waveform, the amplitude of each waveform, and kurtosis. have. In addition, the PPG data may include a representative value such as an average value, a maximum value, or a minimum value in addition to the waveform.

For example, although not shown in the drawings, the hypotension prediction apparatus 100 may further include an EtCO2 sensor for detecting the patient's partial pressure of carbon dioxide. The EtCO2 sensor detects the patient's end-tidal carbon dioxide partial pressure, and it is an indirect indicator of cardiac output by non-invasively measuring carbon dioxide discharged from the lungs. When carbon dioxide is measured, it means that the heart is working and there is spontaneous breathing.

Like the electrocardiogram data, the carbon dioxide partial pressure data may have a waveform corresponding to each unique characteristic, and may include characteristic values such as a time for which each waveform is maintained, an interval between each waveform, an amplitude of each waveform, and kurtosis.

In an embodiment, in operation 22, the data processing unit 120 may pre-process the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data. For example, the data processing unit 120 may each sample (eg, 100HZ downsampling) the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data shown in FIG. 4 , and synchronize the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data. can Here, the synchronization may mean aligning the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data according to the time step.

Before describing operations 23 to 25, a process of machine learning a deep neural network will be first described. The deep neural network of the present invention may generate a hypotension predicted value as an output value by using PPG data, electrocardiogram data, and carbon dioxide partial pressure data as input values as one of the learning models. Here, the value used as the ground truth (or the correct answer) may be data from patients with normal blood pressure or when hypotension actually occurs and continues for a certain period of time. The time point of occurrence of hypotension may be a current time point or a time point n minutes later.

Here, the hypotension may be a case in which a section in which the mean arterial pressure (MAP) is less than 65 mmHg continues for at least 1 minute. In addition, the normal blood pressure may be a case in which the mean arterial blood pressure is greater than or equal to 75 mmHg, and the period lasts for at least 20 minutes.

In an embodiment, in operation 31 , the data acquisition unit 110 may acquire PPG data from a plurality of patients, respectively.

In an embodiment, in operation 32 , the data processing unit 120 may acquire arterial blood pressure data of each of the plurality of users by analyzing the PPG data. For example, the data processing unit 120 may analyze the patient's heart rate, body temperature, stress level, and abnormality or distortion compared to the normal PPG waveform through the PPG data, thereby acquiring the patient's arterial blood pressure data. . A method of acquiring arterial blood pressure data based on the PPG data may be a known method.

In an embodiment, in operation 33 , the data processing unit 120 may classify the arterial blood pressure data into low-pressure data and normal blood pressure data by analyzing the arterial blood pressure data. For example, the data processing unit 120 may analyze the section (b) in the arterial blood pressure data to determine whether the blood pressure is low blood pressure or normal blood pressure. Specifically, for example, the data processing unit 120 analyzes the acquired arterial blood pressure data so that the arterial blood pressure in the section in which the average arterial blood pressure in the section (b) is smaller than the first reference blood pressure (eg, 65 mmHg) lasts for 1 minute or more Data may be classified as hypotensive data, and arterial blood pressure data in which the mean arterial blood pressure is greater than or equal to the second reference blood pressure (eg, 75 mmHg) for 20 minutes or longer may be classified as normotensive data.

In an embodiment, in operation 34 , the data processing unit 120 may extract, as input data, a first predetermined interval from the hypotension data and a predetermined second interval from the normotensive data. For example, the first section and the second section may be sections (a) of FIG. 6 , and the data processing unit 120 first determines whether the arterial blood pressure data of section (b) is hypotension or normal blood pressure, and then at least n The data of section (a) before the minute can be extracted as an input value. That is, the first section is a section having a predetermined length n minutes before the occurrence of a small section lasting more than 1 minute, and the second section is based on the occurrence time of a large section lasting 20 minutes or more in normotensive data It may be a section having a pre-specified length of n minutes before. This is because, after acquiring data before n minutes, it is learning to predict whether or not hypotension will occur after n minutes. Of course, n minutes before is mentioned as a reference for data processing here, but this may be changed to various times such as n minutes and n seconds.

For example, as shown in FIG. 7 , when the data processing unit 120 analyzes the arterial blood pressure data and identifies a hypotensive event in which the mean arterial blood pressure lasts for 1 minute or more, 30 seconds before 5 minutes as an input value of the learning data An input section, a 30-second input section 10 minutes before, and a 30-second input section 15 minutes before can be extracted. This is, of course, only an example, and it is possible to extract input sections of several seconds or more a few minutes before in various lengths and numbers by comprehensively considering whether it is effective to secure a sufficient amount of learning data and to predict hypotension a few minutes in advance.

Meanwhile, although not shown in FIG. 7 , the data processing unit 120 may extract and utilize a 30-second input section of the current time as an input value of the learning data.

Also, for example, as shown in FIG. 8 , when the data processing unit 120 analyzes the arterial blood pressure data and identifies a normotensive section in which the mean arterial blood pressure lasts for 20 minutes or more, the normal blood pressure as an input value of the learning data Based on the center of the section, a 30-second input section at 5-minute intervals, a 30-second input section at 10-minute intervals, and a 30-second input section at 15-minute intervals can be extracted. Of course, this is only an example, and input values can be extracted by comprehensively considering whether it is effective to secure a sufficient amount of training data and to predict normal blood pressure at intervals of several minutes.

Meanwhile, although not shown in FIG. 8 , the data processing unit 120 may extract and utilize a 30-second input section of the current time as an input value of the learning data.

In an embodiment, in operation 35, the deep learning unit 130 may apply the result of classification into hypotension data and normotensive data as correct answer data of the deep neural network and input the extracted input data to the deep neural network. For example, the deep neural network may be a one-dimensional convolutioanal neural network (CNN) or a recurrent neural network (RNN).

For example, in a recurrent neural network (RNN), one or more feature values (vectors) are input, and an output value of a hidden layer or an output layer for a previously input feature value is also input to a newly input feature value. A one-dimensional convolutional neural network (CNN) receives a one-dimensional vector or matrix as an input, and convolution or pooling steps can be performed before the general ANN step. In the convolution step, a multidimensional matrix with weights and a convolution operation are performed. In the pooling step, there are max pooling or mean pooling methods.

For example, in the case of a one-dimensional CNN, one-dimensional features can be more easily extracted from image data by using a one-dimensional filter with different weights. For example, if there is image data with different features for each frequency band, a one-dimensional filter with different weights for each frequency band for each time section is applied to the image data to extract frequency features more precisely than with 2D CNN. can

For example, when the deep neural network is a one-dimensional CNN, as shown in FIG. 9, the deep neural network has 7 convolution layers, 1 fully-connected layer, and 7 max pooling. It may include a max-pooling layer and 8 dropout layers. Also, batch normaization may be applied to the result values derived from each convolutional layer, respectively, and ReLu may be applied as an activation function. Here, the dropout layer may be disposed in each convolutional layer. The convolutional layer may input PPG data, electrocardiogram data, and carbon dioxide partial pressure data (3 x 3000 x L), and may have 64, 32, or 128 filters of 1 x 10 size. Convolutional layers are layers that perform convolution on input data, max pooling layer can reduce the size of information by selecting a maximum value in a given region, and dropout layer is a layer of neurons in one layer to prevent overfitting. Only a certain percentage of the networks connected to neurons in the next layer can be selected. A fully connected layer can perform transformations that connect both neurons in one layer and neurons in the next layer. Through this, the hypotension predicted value may be output. For example, the hypotension predicted value may have 0 and 1, where 0 is normal blood pressure and 1 may mean hypotension.

In an embodiment, in operation 36, the deep learning unit 130 may compare the patient's hypotension predicted value calculated through the deep neural network with the correct answer data. For example, the patient's hypotension predicted value is a value indicating the probability or whether hypotension will occur in the patient n minutes after the PPG data, electrocardiogram data, and carbon dioxide partial pressure data are acquired It may be a value indicating the probability or the occurrence of hypotension. For example, the hypotension prediction value may include data indicating that hypotension may occur with a probability of several%. Alternatively, the hypotension predicted value may have 0 and 1, where 0 is normal blood pressure and 1 may mean hypotension. Also, the current time point or n minutes later may be an example and may be set to various times.

In an embodiment, in operation 37, the deep learning unit 130 may continuously machine-lear the deep neural network by repeatedly performing operations 31 to 36. Through this, the filter value of the deep neural network can be adjusted, and the reliability of the hypotension prediction value can be increased.

The following operations 23 to 25 may be performed using the deep neural network that has been machine-learned in advance through operations 31 to 37.

In an embodiment, in operation 23, the deep learning unit 130 may input the pre-processed PPG data, electrocardiogram data, and carbon dioxide partial pressure data into the machine-learning deep neural network in advance. For example, the deep neural network may be machine-learned in advance based on operations 31 to 36 as a learning model to which a deep learning technique is applied. The deep learning unit 130 may receive three pieces of data to comprehensively analyze changes in waveforms of PPG data, electrocardiogram data, and carbon dioxide partial pressure data. In addition, each of the three pieces of data may be input to the deep neural network or input as one data after being pre-combined with each other.

In an embodiment, in operation 24, the deep learning unit 130 may calculate a patient's hypotension predicted value through a deep neural network. For example, the patient's hypotension predicted value is a value indicating the probability or whether hypotension will occur in the patient n minutes after the PPG data, electrocardiogram data, and carbon dioxide partial pressure data are acquired It may be a value indicating the probability or the occurrence of hypotension. For example, the hypotension prediction value may include data indicating that hypotension may occur with a probability of several%. Alternatively, the hypotension predicted value may have 0 and 1, where 0 is normal blood pressure and 1 may mean hypotension. Also, after n minutes may be an example and may be set to various times.

In an embodiment, in operation 25 , the hypotension determining unit 140 may determine the patient's hypotension. For example, the hypotension determination unit 140 may finally determine whether hypotension is based on the hypotension prediction value calculated by the deep learning unit 130 , and a display or sound output device provided in the hypotension prediction apparatus 100 . It is possible to notify the medical staff who are performing the operation of the occurrence of hypotension at the present time or n minutes later. For example, the hypotension determination unit 140 may display the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data in real time through the display and also the hypotension prediction score. For example, in the case of a high-risk group for low blood pressure, as shown in FIG. 4 , the predicted low blood pressure score may be displayed as 53.8 while being highlighted in red. Here, the hypotension prediction score may be a value in the range of 0 to 100, and as it approaches 0, hypotension does not occur, and as it approaches 100, it may correspond to a high-risk group for hypotension.

As described above, hypotensive shock can have a fatal effect on the patient, and the use of drugs such as anesthetics is limited due to the nature of the operation, and it may take 5-10 minutes or more to prepare necessary devices or drugs such as vasopressors. Therefore, the present invention can accurately predict whether hypotension will occur at the present time or several minutes later based on data acquired in real time, thereby effectively preventing hypotensive shock.

In addition, since the present invention not only analyzes PPG data but additionally considers electrocardiogram data and carbon dioxide partial pressure data, the accuracy and reliability of hypotension prediction are higher than before.

In order to confirm the effect of the present invention, 3487 PPG data, electrocardiogram data, and carbon dioxide partial pressure data were selected from clinical and intraoperative biosignal data collected from 6388 surgical patients, and based on the selected data, training data (train data) and validation data (correct answer value, validation data) were extracted. The training data is 2,440 patients with 28207 events, which are 14359 normotensive events and 13848 hypotension cases, and the validation data is 12508 events with 1047 patients, which are 6198 normal blood pressure and 6310 hypotension. As a result of comparing the learning model using only PPG data and the learning model of the present invention using three data (PPG data, electrocardiogram data, and carbon dioxide partial pressure data), as shown in Table 1 below, hypotension prediction at the present time and 5 minutes later, It was confirmed that both the prediction of hypotension after 10 minutes and the prediction of hypotension after 15 minutes showed that the learning model of the present invention had both AUC and accuracy higher than that of the learning model using only PPG data.

PPG PPG + ECG + CO ₂ When to predict hypotension AUC accuracy AUC accuracy today 0.888 80.7% 0.910 83.2% 5 minutes later 0.804 74.2% 0.844 77.0% after 10 minutes 0.778 72.6% 0.825 73.9% after 15 minutes 0.769 72.3% 0.815 75.3%

A method for predicting a user's hypotension using deep learning-based non-invasive data according to an aspect of the present invention includes: acquiring the user's PPG data, electrocardiogram data, and carbon dioxide partial pressure (CO2 capnography) data; preprocessing the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data; and inputting the pre-processed PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data into a machine-learning deep neural network in advance, and calculating the hypotension predicted value of the user through the deep neural network.

According to various embodiments, the acquiring of the data may include acquiring the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data based on the patient's bio-signals acquired during the operation of the patient. .

According to various embodiments, the pre-processing of the data may include: sampling the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data; and synchronizing the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data.

According to various embodiments, the predicted value of the user's hypotension may be the probability that the user will have hypotension at a current time point after the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data are acquired. .

According to various embodiments, the hypotension prediction value of the patient may be a probability that hypotension will occur in the patient n minutes after the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data are acquired.

According to various embodiments, obtaining PPG data from each of a plurality of users; acquiring arterial blood pressure data of each of the plurality of users by analyzing the acquired PPG data; By analyzing the acquired arterial blood pressure data, the arterial blood pressure data in which the section in which the mean arterial blood pressure is smaller than the first reference blood pressure lasts for 1 minute or more is classified as hypotension data, and the section in which the mean arterial blood pressure is greater than or equal to the second reference blood pressure is 20 classifying arterial blood pressure data lasting for more than a minute as normotensive data; extracting, as input data, a first predetermined interval from the hypotension data and a predetermined second interval from the normotensive data; and applying the result of classification into the hypotension data and the normotensive data as correct answer data of the deep neural network, inputting the extracted input data into the deep neural network, and calculating the user's hypotension predicted value through the deep neural network may include; comparing with the correct answer data.

According to various embodiments, the method may further include continuously machine-learning the deep neural network by repeatedly performing the steps of acquiring, classifying, extracting, and comparing the PPG data, respectively. can

According to various embodiments, the first section is a section having a predetermined length n minutes before the occurrence of the small section lasting 1 minute or longer, and the second section is the 20 minutes or longer in the normotensive data It may be a section having a predetermined length n minutes before the occurrence of the sustained large section.

According to various embodiments, the deep neural network may be a one-dimensional convolutioanal neural network (CNN) or a recurrent neural network (RNN).

According to various embodiments, the deep learning-based patient hypotension prediction program is combined with a computer that is hardware, and may be stored in a medium to execute the method of any one of claims 1 to 9.

The steps of a method or algorithm described in relation to an embodiment of the present invention may be implemented directly in hardware, as a software module executed by hardware, or by a combination thereof. A software module may contain random access memory (RAM), read only memory (ROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, hard disk, removable disk, CD-ROM, or It may reside in any type of computer-readable recording medium well known in the art to which the present invention pertains.

As mentioned above, although embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art to which the present invention pertains know that the present invention may be embodied in other specific forms without changing the technical spirit or essential features thereof. you will be able to understand Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

100: hypotension prediction device
110: data acquisition unit
120: data processing unit
130: deep learning unit
140: low blood pressure determination unit
150 : database

Claims (10)

a data acquisition unit that acquires PPG data, electrocardiogram data, and carbon dioxide partial pressure data of a patient undergoing surgery; and
and a deep learning unit that calculates a hypotension predicted value of the patient by inputting it into a deep neural network based on the acquired PPG data, electrocardiogram data, and carbon dioxide partial pressure data of the patient,
The deep learning unit,
characterized in that the probability of occurrence of hypotension in the patient is calculated n minutes after the patient's PPG data, electrocardiogram data, and carbon dioxide partial pressure data are acquired,
hypotension predictor.
According to claim 1,
The data acquisition unit acquires PPG data from a plurality of patients,
Further comprising a data processing unit to analyze the obtained PPG data to obtain the arterial blood pressure data of the plurality of patients,
The data processing unit analyzes the acquired arterial blood pressure data to classify arterial blood pressure data in which a section in which the mean arterial blood pressure is smaller than the first reference blood pressure lasts for 1 minute or more as hypotension data, and the mean arterial blood pressure is greater than the second reference blood pressure. or classify the arterial blood pressure data in which the same section lasts for 20 minutes or more as normotensive data, and extract a pre-specified first section from the classified hypotensive data and a pre-specified second section from the normotensive data as input data,
The deep learning unit,
Input the results classified into the hypotension data and the normotensive data as correct answer data to the deep neural network,
Inputting the extracted input data into the deep neural network, characterized in that the patient's hypotension predicted value calculated through the deep neural network is compared with the correct answer data,
hypotension predictor.
3. The method of claim 2,
The first section is a section having a predetermined length n minutes before the occurrence of the small section lasting more than 1 minute,
The second section is characterized in that it is a section having a predetermined length n minutes before the occurrence of the large section lasting more than 20 minutes in the normotensive data,
hypotension predictor.
According to claim 1,
The data acquisition unit acquires PPG data from a plurality of patients,
Further comprising a data processing unit to analyze the obtained PPG data to obtain the arterial blood pressure data of the plurality of patients,
The hypotension prediction apparatus analyzes the acquired arterial blood pressure data, classifies the arterial blood pressure data into hypotension data and normotensive data, and extracts the data of the first predetermined section n minutes before from the hypotension data as input data. and extracting the data of the second predetermined section before the n minutes from the normotensive data as input data, characterized in that it is used as learning data for predicting whether the patient has hypotension after n minutes,
hypotension predictor.
According to claim 1,
The data acquisition unit acquires the patient's biosignal based on the monitoring result of the patient in operation, and acquires the PPG data, the electrocardiogram data, and the carbon dioxide partial pressure data based on the acquired biosignal ,
hypotension predictor.
A method performed by a hypotension prediction device, comprising:
acquiring PPG data, electrocardiogram data, and carbon dioxide partial pressure data of a patient undergoing surgery;
and calculating a hypotension predicted value of the patient by inputting it into a deep neural network based on the acquired PPG data, electrocardiogram data, and carbon dioxide partial pressure data of the patient,
The hypotension predicted value calculation step includes:
characterized in that the probability of occurrence of hypotension in the patient is calculated n minutes after the patient's PPG data, electrocardiogram data, and carbon dioxide partial pressure data are acquired,
How to predict hypotension.
7. The method of claim 6,
The hypotension prediction device,
acquiring PPG data from a plurality of patients;
Obtaining arterial blood pressure data of the plurality of patients by analyzing the obtained PPG data,
By analyzing the acquired arterial blood pressure data, arterial blood pressure data in which a section in which the average arterial blood pressure is smaller than the first reference blood pressure lasts for 1 minute or more is classified as hypotension data;
Arterial blood pressure data in which the mean arterial blood pressure is greater than or equal to the second reference blood pressure for 20 minutes or longer is classified as normotensive data;
Extracting a pre-designated first section from the classified hypotension data and a pre-designated second section from the normotensive data as input data,
Input the results classified into the hypotension data and the normotensive data as correct answer data to the deep neural network,
Inputting the extracted input data into the deep neural network, characterized in that the patient's hypotension predicted value calculated through the deep neural network is compared with the correct answer data,
How to predict hypotension.
8. The method of claim 7,
The first section is a section having a predetermined length n minutes before the occurrence of the small section lasting more than 1 minute,
The second section is characterized in that it is a section having a predetermined length n minutes before the occurrence of the large section lasting more than 20 minutes in the normotensive data,
How to predict hypotension.
7. The method of claim 6,
The hypotension device is
acquiring PPG data from a plurality of patients;
Obtaining arterial blood pressure data of the plurality of patients by analyzing the obtained PPG data,
By analyzing the acquired arterial blood pressure data, the arterial blood pressure ?? classify the data into hypotensive data and normotensive data;
In the hypotension data, data of the first predetermined section before the n minutes are extracted as input data, and data of the second section previously designated n minutes before is extracted from the normotensive data as input data, and the patient's Characterized in that it is used as learning data for predicting whether hypotension after n minutes,
How to predict hypotension.
In combination with a computer, which is hardware, the program stored in the medium to execute the method of claim 6 .

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