Method and system for monitoring carbon monoxide in real time during extracorporeal circulation

Abstract

The invention discloses a method and system for monitoring carbon monoxide in real time during extracorporeal circulation, and relates to the technical field of medical monitoring, and the method comprises the following specific steps: light path construction and gas sampling: presetting distributed monitoring nodes in an extracorporeal circulation pipeline, integrating a corresponding laser light source and a photoelectric detector by each probe, sample gas of each node of a body is synchronously collected through the micro-fluidic chip and the micro-flow gas pump array; according to the invention, distributed monitoring nodes are constructed, multi-node synchronous detection is realized by adopting a tunable diode laser absorption spectrum technology, and multi-position synchronous gas sampling is realized by combining a micro-fluidic chip and a micro-flow gas pump array, so that the problems that real-time and non-invasive monitoring cannot be realized and space-time resolution capability is lacked in the prior art are solved; the spatial distribution difference of the carbon monoxide concentration of different parts of the extracorporeal circulation pipeline can be obtained in real time, the dynamic law of the carbon monoxide concentration along with time change is analyzed, and more comprehensive and accurate data support is provided for medical evaluation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical monitoring, in particular to a method and system for real-time monitoring of carbon monoxide during extracorporeal circulation. BACKGROUND

[0002] Extracorporeal circulation technology plays a crucial role in modern medical field and is widely used in complex medical scenarios such as heart surgery and organ transplantation. In the process of extracorporeal circulation, to ensure the safety of patients and the smooth progress of surgery, it is necessary to monitor the physiological parameters of patients in real time and accurately. Carbon monoxide, as an endogenous gas transmitter, plays a unique role in the physiological and pathological processes of the human body. Therefore, real-time and accurate monitoring of carbon monoxide levels during extracorporeal circulation is of great significance for medical personnel to comprehensively assess the physiological state of patients, timely detect potential complications, develop reasonable treatment plans, and improve the prognosis of patients.

[0003] Currently, existing carbon monoxide monitoring methods have many limitations and cannot meet the actual needs during extracorporeal circulation. Traditional detection methods are difficult to achieve real-time and non-invasive monitoring during extracorporeal circulation, and the operation process is complex and tedious. This not only increases the workload of medical staff, but also may affect the reliability of the monitoring results due to untimely or inaccurate operation, thereby delaying timely intervention for patients. Gas detection methods based on optical principles have weak anti-interference ability in the complex environment of extracorporeal circulation and are easily disturbed by other factors, resulting in insufficient detection accuracy. At the same time, this method cannot well adapt to the complex fluid environment in the extracorporeal circulation pipeline, further affecting the accuracy of the monitoring data. In addition, existing technologies can only monitor the carbon monoxide concentration at a single location and cannot obtain the spatial distribution difference of carbon monoxide concentration at different parts of the pipeline, nor can it analyze the dynamic law of its change with time. This makes it difficult for doctors to locate the source of carbon monoxide abnormalities and accurately assess the performance of key components in the extracorporeal circulation system, thereby adversely affecting medical judgment and decision-making. SUMMARY

[0004] The purpose of the present application is to make up for the shortcomings of the prior art, provide a carbon monoxide real-time monitoring method and system during extracorporeal circulation, which can realize multi-node synchronous detection by constructing distributed monitoring nodes and using tunable diode laser absorption spectroscopy technology, realize multi-position synchronous gas sampling by combining microfluidic chips, effectively solve the problem that the existing method cannot realize real-time and non-invasive monitoring, at the same time, by integrating multiple auxiliary laser light sources for interference gas compensation, using multivariate linear regression algorithm to establish an interference compensation model, the accuracy and anti-interference ability of the detection are improved, in addition, by performing time dimension, space dimension and space-time correlation analysis on the concentration data of multiple nodes, the dynamic change rule and spatial distribution difference of carbon monoxide concentration are obtained, the abnormal source is located and the performance of the key components is evaluated, by setting multi-level alarm mechanism and data storage and backtracking analysis function, comprehensive and accurate monitoring information is provided for medical personnel, which helps to improve the safety and success rate of extracorporeal circulation operation.

[0005] The present application provides the following technical solutions to solve the above technical problems: on the one hand, a carbon monoxide real-time monitoring method during extracorporeal circulation, the method comprising the following specific steps: Optical path construction and gas sampling: presetting distributed monitoring nodes on the extracorporeal circulation pipeline, each probe integrating corresponding laser light source and photodetector, synchronously collecting sample gas at each node of the body through microfluidic chips and micro-flow gas pump arrays; Multi-node synchronous detection: each monitoring node uses a distributed feedback tunable diode laser, which realizes jump-free scanning through independent temperature control and current driving, and synchronously collects and converts the attenuation signal of laser passing through sample gas into an electrical signal output; Interference gas compensation and concentration inversion: each probe integrates an auxiliary laser light source, a compensation model is established to compensate the carbon monoxide detection signal in real time, and the real-time carbon monoxide concentration of each node is inverted; Time and space resolution analysis and data feedback: through time series analysis of the concentration data of multiple nodes, the concentration mutation point is identified, the concentration difference and gradient of key nodes and the performance parameters of key components are calculated, and the concentration distribution is visualized, the abnormal position is located combined with blood flow velocity, the data is synchronously transmitted and an alarm is given; Data storage and backtracking analysis: store the monitoring data in a medical standard format, cover the whole extracorporeal circulation and a preset time period after the operation which can be adjusted, support backtracking analysis of data through keyword search.

[0006] Furthermore, in the optical path construction and gas sampling steps, monitoring probes are set at preset positions in the extracorporeal circulation pipeline to form distributed monitoring nodes. Each monitoring probe integrates a set of tunable diode laser sources and a set of photodetectors. The center wavelength of the tunable diode laser source corresponds to the characteristic absorption wavelength of carbon monoxide. Multi-location synchronous gas sampling is achieved through a microfluidic chip array. The microfluidic chip includes independent sampling channels, gas pretreatment channels, and detection channels. The gas pretreatment channel has a built-in hydrophilic membrane, and each sampling channel corresponds to one monitoring node. The sampling flow rate is controlled by a micro-flow pump array. Each sampling channel in the micro-flow pump array is equipped with a micro-pump to synchronously introduce the sample gas from each monitoring node into the corresponding micro-gas absorption pool. The micro-gas absorption pool is integrated into the detection channel of the microfluidic chip and adopts a multi-reflection structure. The detection optical path of each monitoring node is independent and works synchronously.

[0007] Furthermore, in the multi-node synchronous detection step, the laser source of each monitoring node adopts a distributed feedback tunable diode laser, and its center wavelength is calibrated to the characteristic absorption wavelength of carbon monoxide; each laser source is equipped with an independent temperature control module and current drive module to achieve mode-skipping scanning; after the scanning laser passes through the sample gas in the corresponding micro gas absorption cell, the photodetectors of each node synchronously collect the attenuated laser signal and convert the optical signal into an electrical signal to be output to the data processing module.

[0008] Furthermore, in the interfering gas compensation and concentration inversion step, each monitoring probe integrates multiple sets of auxiliary laser sources, with the center wavelength of each set of auxiliary laser sources corresponding to the characteristic absorption wavelength of a preset interfering gas. The absorption intensity of each interfering gas at the corresponding wavelength is detected by the auxiliary laser sources. Combined with a preset database of interfering gas absorption coefficients, an interference compensation model for each monitoring node is established. This interference compensation model uses a multiple linear regression algorithm to compensate for the carbon monoxide detection signal in real time, and its formula is: ,in, To compensate for the effective absorption intensity of carbon monoxide, This represents the original absorption intensity of carbon monoxide. To determine the types and quantities of interfering gases, For the first Correction factor for the absorption coefficient of interfering gases. For the first Measurement of the absorption intensity of interfering gases, For the first The actual partial pressure of the interfering gas As a reference voltage divider, The actual temperature of the sample gas. For reference temperature, This is a correction term for environmental disturbances.

[0009] Further, in the interference gas compensation and concentration inversion step, the real-time carbon monoxide concentration of each node is inverted. Specifically, based on the Lambert-Beer law, a continuous two-section curve fitting method is used for concentration inversion: two intervals are divided according to the carbon monoxide concentration, that is, for the low concentration interval, for the high concentration interval, for the concentration section threshold value, for the low concentration interval, the concentration inversion formula is: for the high concentration interval, the concentration inversion formula is: wherein, : the real-time carbon monoxide concentration in the low / high concentration interval, , , is the fitting coefficient of the low concentration interval, , , is the fitting coefficient of the high concentration interval, is the sampling flow correction coefficient, is the actual sampling flow of the microfluidic chip, is the standard sampling flow, is the blood flow velocity coupling coefficient, is the actual blood flow velocity in the extracorporeal circulation pipeline, is the standard blood flow velocity, and the concentration interval threshold value is determined according to clinical data analysis; the concentration of each monitoring node is obtained by respectively inverting the concentration of each monitoring node after compensating the signal.

[0010] Further, in the space-time resolution analysis and data feedback step, the concentration data of multiple nodes are processed by time series analysis, specifically: time dimension analysis: the concentration data of each monitoring node is established in time series according to the time stamp, the concentration change rate is calculated by using the sliding window method, and the concentration mutation point is identified based on the preset change rate determination threshold; spatial dimension analysis: the concentration difference and concentration gradient between the preset key nodes are calculated, the concentration gradient is the ratio of the concentration difference to the corresponding pipeline length, the removal efficiency of the oxygenator in the extracorporeal circulation system is calculated based on the concentration difference between the key nodes, and the concentration distribution of each monitoring node is visualized by a heat map; spatial and temporal correlation analysis: the time delay of concentration change of different nodes is analyzed by using cross-correlation algorithm, the blood flow rate data in the extracorporeal circulation pipeline are synchronously collected by a blood flow sensor, and the distance between the potential abnormal position and the monitoring node is calculated based on the correlation between the time delay and the blood flow rate.

[0011] Furthermore, in the spatiotemporal resolution analysis and data feedback step, the sliding window method is used to calculate the concentration change rate, and concentration abrupt change points are identified based on a preset change rate judgment threshold. The calculation formula is as follows: ,in, yes The rate of change of carbon monoxide concentration at a certain monitoring node at a given time. yes The carbon monoxide concentration at the monitoring node should be monitored at all times. yes The carbon monoxide concentration at the monitoring node should be monitored at all times. It is the concentration sampling time interval. It is the coefficient of influence of temperature fluctuation. yes Time and Temperature interpolation at time, yes The threshold for determining concentration mutations at the monitoring node at any given time. It is the threshold correction coefficient. It is the number of sampling points within the sliding window. yes to The average concentration at any given time.

[0012] Furthermore, in the spatiotemporal resolution analysis and data feedback step, the clearance efficiency of the oxygenator in the extracorporeal circulation system is calculated based on the concentration difference between key nodes. The calculation formula is as follows: ,in, For oxygenator scavenging efficiency. This refers to the oxygenator outlet concentration. This refers to the oxygenator inlet concentration. This is the background concentration correction value.

[0013] Furthermore, in the spatiotemporal resolution analysis and data feedback step, a cross-correlation algorithm is used to analyze the time delay of concentration changes at different nodes. By combining blood flow velocity data within the extracorporeal circulation tubing, the distance between potential abnormal locations and monitoring nodes is calculated using the following formula: ,in, The distance between the abnormal location and the monitoring node. Mean blood flow velocity, This is the pressure influence coefficient. Due to pipeline pressure difference, Standard atmospheric pressure.

[0014] On the other hand, a real-time carbon monoxide monitoring system during extracorporeal circulation, the system comprising: Sensor module: contains a distributed sensor array composed of multiple medical-grade monitoring probes with primary / auxiliary laser light sources and photodetectors, a microfluidic chip array with independent sampling units, and a synchronous control unit that synchronizes the laser scanning timing and sampling pump working state of each node using a logic control chip. The monitoring probes are connected to the external circulation pipeline through a quick-mount clamp with a flexible protective pad, and the microfluidic chips are connected to the pipeline through a sterile puncture sampling port with the outlet connected to a waste gas collection device. Data processing module: uses a logic control chip + processor dual-core architecture circuit board. The logic control chip module is responsible for laser signal synchronous demodulation, data filtering and caching. The processor module runs a special system and integrates time series analysis, concentration inversion and threshold judgment algorithm library and interfaces with the hospital information system. The sensor interface expansion unit contains blood flow velocity and temperature / pressure sensor interfaces corresponding to each monitoring node for collecting pipeline-related data. Display and alarm module: includes a high-definition touch display screen that supports split-screen display, an alarm device that contains an audible and visual alarm and a wireless early warning module with hierarchical alarm, and a data export unit that supports exporting standard monitoring reports and spatiotemporal analysis reports containing concentration curves, heat maps, and alarm records. Gas sampling and processing module: includes a microfluidic gas pump array composed of micro-pump bodies matched with the number of monitoring nodes, with adjustable flow and closed-loop control, a gas pretreatment unit containing a hydrophilic membrane built-in microfluidic chip and a filter element at the gas pump inlet, and a waste gas treatment unit containing a special collection device that collects exhaust gas from each node and processes waste according to specifications.

[0015] Compared with the prior art, the real-time monitoring method and system for carbon monoxide during extracorporeal circulation have the following beneficial effects: First, the present application solves the problem of real-time, non-invasive monitoring and lack of spatiotemporal resolution by constructing a distributed monitoring node, using tunable diode laser absorption spectroscopy technology for multi-node synchronous detection, combining microfluidic chips and micro-flow gas pump arrays for multi-position synchronous gas sampling, and providing more comprehensive and accurate data support for medical evaluation by real-time acquisition of spatial distribution differences of carbon monoxide concentration at different parts of the extracorporeal circulation pipeline and analysis of its dynamic rules over time.

[0016] Second, the present application uses time series analysis algorithms to dynamically process multi-node concentration data, analyzes carbon monoxide concentration changes from time, space, and spatiotemporal correlation dimensions, not only identifies concentration mutation points, calculates key component performance parameters, and generates concentration distribution heat maps, but also locates potential abnormal positions combined with blood flow velocity data. In addition, the system supports data storage and backtracking analysis, making it easy for medical staff to retrieve data after surgery, providing comprehensive and detailed information for subsequent medical decision-making and research, and helping to improve the overall level and safety of extracorporeal circulation medical treatment.

[0017] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the practice of the invention. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0019] Figure 1 This is a schematic diagram of a real-time carbon monoxide monitoring system during extracorporeal circulation. Figure 2 This is a flowchart of a method for real-time monitoring of carbon monoxide during extracorporeal circulation. Detailed Implementation

[0020] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below. Example

[0021] This embodiment provides a real-time carbon monoxide monitoring system during extracorporeal circulation, such as... Figure 1 As shown, it includes a sensing module, a data processing module, a display and alarm module, and a gas sampling and processing module; The sensing module comprises a distributed sensor array, a microfluidic chip array, and a synchronization control unit. The distributed sensor array consists of multiple independent monitoring probes. Each probe contains a main laser source corresponding to the characteristic wavelength of carbon monoxide, multiple auxiliary laser sources corresponding to the characteristic wavelengths of interfering gases, and a photodetector adapted to the infrared band. The probes are connected to the extracorporeal circulation tubing via a medical-grade quick-release clamp with a flexible protective pad on the inner wall. The microfluidic chip array is fabricated using microfabrication technology. Each chip contains multiple integrated sampling channels, a water removal channel (with a built-in high-precision hydrophilic filter membrane), and a sampling unit with a micro gas absorption pool. The chip inlet is connected to the sterile puncture sampling port of the extracorporeal circulation tubing via a medical-grade tubing, and the outlet is connected to a waste gas collection device. The synchronization control unit is integrated into the sensing module and uses a logic control chip to synchronize the laser scanning timing of each probe with the operating status of the sampling pump.

[0022] The data processing module adopts a logic control chip + processor dual-core architecture circuit board. The logic control chip module is responsible for multi-node laser signal synchronous demodulation (second harmonic detection), data filtering (anti-interference algorithm), and caching. The processor module integrates a time series analysis algorithm library containing sliding window calculation, cross-correlation analysis, and heat map generation. The concentration inversion algorithm library pre-stores high and low concentration segment fitting equations and interference compensation models. The threshold judgment module supports custom alarm thresholds and interfaces with the hospital information system through a network interface. The sensor interface expansion unit includes a blood flow velocity sensor interface connected to a blood flow detection device and temperature / pressure sensor interfaces corresponding to each monitoring node.

[0023] The display and alarm module includes a high-definition touch display screen (supporting split-screen display: the first display area displays concentration values and a change curve with a switchable time axis, the second display area displays a scalable pipeline concentration heat map, and the third display area displays key component performance parameters and mutation point statistics), an alarm device including an audible and visual alarm installed in a predetermined area and a wireless warning module (divided into three levels of alarm), and a data export unit supporting the export of standard reports and spatio-temporal analysis reports containing concentration curves, heat maps, and alarm records.

[0024] The gas sampling and processing module includes a micro-flow gas pump array composed of micro-pumps matched with the number of monitoring nodes, adjustable flow, and closed-loop control, a gas pretreatment unit including a hydrophilic membrane built-in microfluidic chip and a filter element at the gas pump inlet (to remove blood splashes and organic impurities), and a waste gas treatment unit including a dedicated collection device that aggregates exhaust gas and processes waste according to specifications.

[0025] The photodetector of the sensing module is connected to the logic control chip module of the data processing module through a signal transmission line. The sampling pump of the microfluidic chip array is connected to the synchronous control unit through a control line. The synchronous control unit is connected to the data processing module through a data line. The processor module of the data processing module is connected to the display terminal, alarm device, and data export unit of the display and alarm module, and the micro-flow gas pump array of the gas sampling and processing module through data lines. The micro-flow gas pump array of the gas sampling and processing module is connected to the sampling channel inlet of the microfluidic chip array through a gas pipeline. Embodiment

[0026] This embodiment is applied to the extracorporeal circulation process of adult heart valve replacement surgery, which needs to monitor the carbon monoxide concentration changes of the oxygenator, arterial filter, and venous return section to evaluate the patient's oxygen metabolism status and the stability of the extracorporeal circulation system. Monitoring probes are set at predetermined key positions of the extracorporeal circulation pipeline to form distributed monitoring nodes. Each monitoring probe is fixed to the pipeline through a quick-mount clamp with a flexible protective pad, ensuring that the laser entrance and exit ports are perpendicular to the pipeline axis, and the sampling port faces the side of the pipeline to avoid blood flow impact. The sampling channel entrance of the microfluidic chip array is connected with the sterile puncture sampling port of each monitoring node through medical-grade pipelines, and the sampling channel exit is connected with a special waste gas collection device through a pipeline; the signal output lines of each monitoring probe are connected with the logic control chip module interface of the data processing module, the blood flow velocity sensor is installed at a preset pipeline position, the temperature / pressure sensor is arranged on the outer wall of the pipeline of each monitoring node, and is connected with the data processing module through a sensor interface expansion unit; the display terminal is placed beside the operating table of the surgeon, the audible and visual alarm is fixed at a conspicuous position in the operating room, and the wireless early warning module is paired and connected with the mobile terminal of the surgeon. As shown in Figure 2 , after the extracorporeal circulation machine is started, all monitoring nodes are automatically activated, the distributed feedback tunable diode laser of each node synchronously emits laser of a corresponding carbon monoxide characteristic absorption wavelength under the control of the temperature control module and the current driving module, after the laser passes through the micro gas absorption cell in the microfluidic chip, the photodetector collects the attenuation signal and converts it into an electrical signal which is transmitted to the data processing module; the logic control chip module performs second harmonic demodulation on the electrical signal, extracts the characteristic signal peak, removes high-frequency noise by using an anti-interference filtering algorithm, and simultaneously combines the interference gas absorption signal collected by the auxiliary laser light source to calculate the compensated absorption intensity by using an interference compensation formula , wherein is the effective absorption intensity of carbon monoxide after compensation, is the original absorption intensity of carbon monoxide, is the number of interference gas types, is the absorption coefficient correction factor of the th interference gas, is the measured absorption intensity of the th interference gas, is the actual partial pressure of the th interference gas, is the reference partial pressure, is the actual temperature of the sample gas, is the reference temperature, is the environmental interference correction term.

[0027] The processor module of the data processing module calculates the real-time concentration of each node according to the compensated absorption intensity and by combining the concentration segmented threshold value to select the corresponding concentration fitting equation – the low-concentration interval ( ) is calculated by formula , and the high-concentration interval ( ) is calculated by formula , wherein is the carbon monoxide concentration corresponding to the interval, , , is the fitting coefficient of the low-concentration interval, , , These are the fitting coefficients for the high concentration range. It is the sampling flow rate correction factor. This is the actual sampled flow rate of the microfluidic chip. This is the standard sampling flow rate. The blood flow velocity coupling coefficient is... It is the actual blood flow velocity within the extracorporeal circulation tubing. It is the standard blood flow velocity. The concentration segment thresholds are used; the oxygenator scavenging efficiency formula is used. Calculate the cleaning efficiency, where For oxygenator scavenging efficiency. This refers to the oxygenator outlet concentration. This refers to the oxygenator inlet concentration. This is the background concentration correction value; if the clearance efficiency is lower than the alarm lower limit, the system triggers the corresponding level alarm. The surgeon views the concentration distribution heatmap on the display terminal, combines it with the data collected by the blood flow velocity sensor to determine the cause of the abnormality, and then adjusts the parameters of the extracorporeal circulation system.

[0028] During the core operational phase of valve replacement surgery, the system continuously performs spatiotemporal resolved analysis, using the concentration change rate formula in the time dimension. Calculate the concentration change rate at each node, where yes The rate of change of carbon monoxide concentration at a certain monitoring node at a given time. yes The carbon monoxide concentration at the monitoring node should be monitored at all times. yes The carbon monoxide concentration at the monitoring node should be monitored at all times. It is the concentration sampling time interval. It is the coefficient of influence of temperature fluctuation. yes Time and Temperature interpolation at any given time; and simultaneously using the abrupt change threshold formula. Calculate the dynamic threshold, its yes to If the average concentration at any given time does not exceed a threshold, there are no abrupt change points. Spatially, the concentration difference between the oxygenator inlet and outlet is calculated, and the scavenging efficiency is calculated using the scavenging efficiency formula. A concentration distribution heatmap shows the concentration gradient changes at each node. In the spatiotemporal correlation analysis, a cross-correlation algorithm is used to obtain the time delay of concentration changes at different nodes. Combined with mean blood flow velocity Pressure influence coefficient Pipeline pressure difference Through the anomaly location formula Calculate potential abnormal position distance, wherein is the abnormal position and monitoring node distance, is the standard atmospheric pressure, according to the calculation results to determine whether there is an abnormal source.

[0029] If the concentration of a monitoring node exceeds the corresponding alarm threshold, the system immediately triggers the corresponding level alarm, and pushes the warning information (including abnormal node, concentration value, change trend) to the preset mobile terminal; medical staff can trace back the concentration curve within the preset time period through the display terminal, and judge the abnormal reason combined with the patient's clinical test results. If it is caused by temporary physiological metabolism change, no special intervention is needed, and the alarm will be automatically released after the concentration falls to the normal range. In the stage of gradually reducing the flow of the extracorporeal circulation machine and preparing to remove, the system focuses on monitoring the concentration of key nodes and the removal efficiency of the oxygenator. With the adjustment of blood flow, the real-time concentration of key nodes is calculated through the concentration inversion formula, the removal efficiency of the oxygenator is calculated through the removal efficiency formula, and the concentration change rate is calculated through the concentration change rate formula to confirm that there is no abnormal mutation. The data processing module confirms that the change trend of the concentration of each node is synchronized with the adjustment of blood flow through spatiotemporal correlation analysis, and there is no abnormal source signal. After the extracorporeal circulation is removed, the system continues to monitor for a preset period of time after the operation, and then automatically stops monitoring; the data processing module stores the whole monitoring data, removal efficiency, and alarm record in the standard format of medical data; medical staff can retrieve the monitoring data by inputting the patient identification information through the display terminal, and export the monitoring data report and spatiotemporal analysis report in the standard format for postoperative condition review and surgical effect evaluation.

[0030] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the technical solution of the present application, and any equivalent embodiments with equivalent changes are equivalent. Any simplification, modification, equivalent change and modification of the above embodiments based on the technical essence of the present application are still within the scope of the technical solution of the present application.

Claims

1. A method for real-time monitoring of carbon monoxide during extracorporeal circulation, characterized in that, The method comprises: Optical path construction and gas sampling: preset distributed monitoring nodes in the extracorporeal circulation pipeline, each probe integrates corresponding laser light source and photodetector, and sample gas at each node is synchronously collected through microfluidic chip and micro-flow gas pump array; Multi-node synchronous detection: each monitoring node uses a distributed feedback tunable diode laser, which realizes jump-free scanning through independent temperature control and current driving, and synchronously collects the attenuation signal of laser passing through the sample gas and converts it into an electrical signal output; Interference gas compensation and concentration inversion: each probe integrates an auxiliary laser light source, a compensation model is established to compensate the carbon monoxide detection signal in real time, and the real-time carbon monoxide concentration of each node is inverted; Temporal and spatial resolution analysis and data feedback: the multi-node concentration data is processed by time series analysis, the concentration mutation point is identified, the concentration difference and gradient of the key node and the performance parameters of the key components are calculated, and the concentration distribution is visualized, combined with the blood flow velocity to locate the abnormal position, and the data is synchronously transmitted and alarmed; Data storage and backtracking analysis: store the data of the whole monitoring period according to the medical standard format, support keyword retrieval and backtracking, and the storage period can be adjusted.

2. The method of claim 1, wherein, In the optical path construction and gas sampling step, monitoring probes are arranged at preset positions in the extracorporeal circulation pipeline to form distributed monitoring nodes; a group of tunable diode laser light sources and a group of photodetectors are integrated in each monitoring probe, the center wavelength of the tunable diode laser light source corresponds to the carbon monoxide characteristic absorption wavelength; multi-position synchronous gas sampling is realized through a microfluidic chip array, the microfluidic chip includes independent sampling channels, a gas pretreatment channel and a detection channel, a hydrophilic membrane is built-in the gas pretreatment channel, and each sampling channel corresponds to one monitoring node; the sampling flow is controlled through a micro-flow gas pump array, one micro pump body is equipped in each sampling channel in the micro-flow gas pump array, the sample gas of each monitoring node is synchronously introduced into the corresponding micro gas absorption cell, the micro gas absorption cell is integrated in the detection channel of the microfluidic chip, and a multiple reflection structure is adopted, and the detection light paths of each monitoring node are independent and work synchronously.

3. The method of claim 1, wherein the method is performed during cardiopulmonary bypass. In the multi-node synchronous detection step, the laser light source of each monitoring node uses a distributed feedback tunable diode laser, the center wavelength of which is calibrated to the carbon monoxide characteristic absorption wavelength; each laser light source is configured with an independent temperature control module and a current driving module to realize jump-free scanning; after the scanning laser passes through the sample gas in the corresponding micro gas absorption cell, the photodetector of each node synchronously collects the attenuated laser signal, and converts the optical signal into an electrical signal output to a data processing module.

4. The method of claim 1, wherein, The interference gas compensation and concentration inversion steps, each monitoring probe is additionally integrated with multiple groups of auxiliary laser light sources, and the center wavelengths of the auxiliary laser light sources correspond to the characteristic absorption wavelengths of the preset interference gases respectively; the absorption intensity of each interference gas to the corresponding wavelength laser is detected by the auxiliary laser light source, a preset interference gas absorption coefficient database is combined, an interference compensation model of each monitoring node is established, the interference compensation model adopts a multiple linear regression algorithm to compensate the carbon monoxide detection signal in real time, and the formula is: Wherein, is the effective absorption intensity of the compensated carbon monoxide, is the original absorption intensity of the carbon monoxide, is the number of interference gas types, is the absorption coefficient correction factor of the first interference gas, is the measured absorption intensity of the first interference gas, is the actual partial pressure of the first interference gas, is the reference partial pressure, is the actual temperature of the sample gas, is the reference temperature, is the environmental interference correction term.

5. The method of claim 1, wherein, The interference gas compensation and concentration inversion step, the real-time carbon monoxide concentration of each node is inverted, specifically, based on Lambert Beer's law, the concentration inversion is carried out by adopting continuous two-section curve fitting method: two intervals are divided according to carbon monoxide concentration, that is The low concentration interval, The high concentration interval, The concentration section threshold value, for the low concentration interval, the concentration inversion formula is: For the high concentration interval, the concentration inversion formula is: Wherein, The real-time carbon monoxide concentration of low / high concentration interval, , , The fitting coefficient of low concentration interval, , , The fitting coefficient of high concentration interval, The sampling flow correction coefficient, The actual sampling flow of microfluidic chip, The standard sampling flow, The blood flow velocity coupling coefficient, The actual blood flow velocity in extracorporeal circulation pipeline, The standard blood flow velocity, the demarcation value of concentration interval Determined according to clinical data analysis; by respectively inverting the concentration of the compensated signals of each monitoring node, the real-time carbon monoxide of each monitoring node is obtained.

6. The method of claim 1, wherein, In the temporal and spatial resolution analysis and data feedback step, the multi-node concentration data is processed by time series analysis, specifically: Time dimension analysis: time series is established for the concentration data of each monitoring node according to the time stamp, the concentration change rate is calculated by using the sliding window method, and the concentration mutation point is identified based on the preset change rate judgment threshold; Spatial dimension analysis: calculate the concentration difference between the preset key nodes and the concentration gradient, which is the ratio of the concentration difference and the corresponding pipeline length, calculate the oxygenator removal efficiency in the extracorporeal circulation system based on the concentration difference between the key nodes, and visualize the concentration distribution of each monitoring node through heat map; Space-time correlation analysis: use cross-correlation algorithm to analyze the time delay of concentration change in different nodes, combine the blood flow velocity data in the extracorporeal circulation pipeline, which is synchronously collected by blood flow sensor, calculate the distance between potential abnormal position and monitoring node based on the correlation of time delay and blood flow velocity.

7. The method of claim 1, wherein the method is used during cardiopulmonary bypass. In the spatiotemporal resolution analysis and data feedback step, the sliding window method is used to calculate the concentration change rate, and concentration abrupt change points are identified based on a preset change rate judgment threshold. The calculation formula is as follows: ,in, yes The rate of change of carbon monoxide concentration at a certain monitoring node at a given time. yes The carbon monoxide concentration at this monitoring node should be monitored at all times. yes The carbon monoxide concentration at this monitoring node should be monitored at all times. It is the concentration sampling time interval. It is the coefficient of influence of temperature fluctuation. yes Time and Temperature interpolation at time, yes The threshold for determining concentration mutations at the monitoring node at any given time. It is the threshold correction coefficient. It is the number of sampling points within the sliding window. yes to The average concentration at any given time.

8. The method of claim 6, wherein the method is used during cardiopulmonary bypass. In the spatio-temporal resolution analysis and data feedback step, the oxygenator removal efficiency in the extracorporeal circulation system is calculated based on the concentration difference between the key nodes, and the calculation formula is: wherein, is the oxygenator removal efficiency, is the oxygenator outlet concentration, is the oxygenator inlet concentration, is the background concentration correction value.

9. The method of claim 6, wherein the method is used during cardiopulmonary bypass. The time-space resolution analysis and the data feedback step adopt cross-correlation algorithm to analyze the time delay of the concentration change of different nodes , combined with the blood flow rate data in the extracorporeal circulation pipeline, the distance between the potential abnormal position and the monitoring node is calculated, and the calculation formula is: , wherein, is the distance between the abnormal position and the monitoring node, is the average blood flow rate, is the pressure influence coefficient, is the pressure difference of the pipeline, is the standard atmospheric pressure.

10. A system for real-time monitoring of carbon monoxide during extracorporeal circulation, the system being suitable for use in the method for real-time monitoring of carbon monoxide during extracorporeal circulation according to any one of claims 1 to 9, characterized in that, The system comprises: Sensor module: contains a distributed sensor array composed of multiple medical-grade monitoring probes with primary / auxiliary laser light sources and photodetectors, a microfluidic chip array with independent sampling units, and a synchronous control unit that synchronizes the laser scanning timing and sampling pump working state of each node using a logic control chip, the monitoring probe is connected to the extracorporeal circulation pipeline through a quick-mount clamp with a flexible protective pad, the microfluidic chip is connected to the pipeline through a sterile puncture sampling port and the outlet is connected to a waste gas collection device; Data processing module: uses a logic control chip + processor dual-core architecture circuit board, the logic control chip module is responsible for laser signal synchronous demodulation, data filtering and caching, the processor module runs a special system and integrates time series analysis, concentration inversion and threshold judgment algorithm library and interfaces with hospital information system, sensor interface expansion unit contains blood flow velocity and temperature / pressure sensor interface corresponding to each monitoring node, used for collecting pipeline related data; Display and alarm module: includes a high-definition touch display screen that supports split-screen display, an alarm device that contains an audible and visual alarm and a wireless warning module and has hierarchical alarm, and a data export unit that supports exporting standard monitoring reports and space-time analysis reports containing concentration curves, heat maps and alarm records; Gas sampling and processing module: includes a microfluidic gas pump array composed of micro-pump bodies matched with the number of monitoring nodes, with adjustable flow and closed-loop control, a gas pretreatment unit containing a hydrophilic membrane built-in microfluidic chip and a filter element at the gas pump inlet, and a waste gas treatment unit containing a special collection device that collects exhaust gas from each node and processes waste according to specifications.

Images