A device for real-time feedback of quality of cardiopulmonary resuscitation and depth monitoring of chest compression

Abstract

This invention provides a real-time feedback device for cardiopulmonary resuscitation (CPR) quality and a chest compression depth monitoring device. Addressing the widespread problem of substandard clinical CPR quality, it integrates multi-sensor technology and intelligent algorithms to achieve high-precision, personalized CPR quality monitoring and feedback. The device's main functions are: 1) providing real-time voice and visual feedback to guide rescuers in precisely controlling compression depth (5-6 cm for adults), frequency (100-120 compressions / min), and chest wall recoil, thereby improving the rate of achieving the required compression depth and the rate of complete chest wall recoil; 2) recording CPR data throughout the entire process and generating standardized quality reports, providing objective evidence for emergency care quality improvement, medical evidence collection, and personnel training; and 3) adapting to various scenarios such as pre-hospital emergency care and emergency resuscitation rooms, it can be integrated into AED devices or monitors, significantly improving the success rate of resuscitation both inside and outside hospitals, and providing key technical support for the resuscitation of cardiac arrest patients.

Description

Technical Field

[0001] This invention relates to the field of medical devices and emergency equipment technology, and in particular to a device for real-time feedback of cardiopulmonary resuscitation quality and monitoring of chest compression depth. Background Technology

[0002] Sudden cardiac arrest (SCA) is the leading cause of sudden death worldwide, and high-quality chest compressions are crucial for successful cardiopulmonary resuscitation (CPR). However, the quality of CPR is generally substandard in clinical practice. The main reasons for poor CPR quality include: Current monitoring technologies lack precision: Traditional CPR quality monitoring relies mainly on visual inspection or experience-based judgment by healthcare workers, resulting in significant errors. Some AED devices use a single accelerometer to measure compression depth, but the quadratic integral of acceleration is easily affected by baseline drift, chest wall movement interference, and compression angle, with measurement errors reaching ±1.5cm or more. Furthermore, they cannot distinguish between effective compressions and passive chest wall movements.

[0003] Lack of quantitative assessment of chest wall recoil integrity: Current technology can only monitor compression depth and frequency, and cannot quantitatively assess whether chest wall recoil is complete. Incomplete chest wall recoil leads to insufficient intrathoracic negative pressure, significantly reducing cardiac output and coronary perfusion pressure, which is an important factor affecting resuscitation success rate.

[0004] Compression strategies lack personalization: Existing equipment uses uniform AHA recommended compression parameters without considering individual differences such as patient age, weight, and chest wall compliance. For children, obese patients, or patients with osteoporosis, a uniform compression depth may lead to complications such as insufficient compression or rib fractures.

[0005] Feedback is untimely and limited in form: Most devices only provide audible and visual alarms, lacking real-time voice guidance and dynamic adjustment suggestions. In the tense emergency environment, medical staff find it difficult to simultaneously monitor the device screen and the patient's condition, resulting in ineffective communication of feedback information.

[0006] Data cannot be traced and analyzed: Most existing equipment does not have the function of complete recording and post-event analysis of CPR process data, and cannot provide objective basis for improving the quality of first aid and training. Summary of the Invention

[0007] To address the technical problems existing in the prior art, the present invention provides the following technical solution: A real-time feedback device for cardiopulmonary resuscitation quality and chest compression depth monitoring includes a wearable sensing unit and a terminal display feedback unit. The wearable sensing unit includes a flexible pressure sensor array, a three-axis accelerometer module, a main control processing unit, and a wireless communication module. The flexible pressure sensor array is used to acquire compression pressure signals in real time, and the three-axis accelerometer module is used to synchronously acquire three-dimensional acceleration signals of the chest wall. The main control processing unit uses a Kalman filter algorithm to fuse pressure and acceleration data to calculate compression depth, frequency, compression-release ratio, and chest wall rebound integrity index. The wireless communication module transmits the calculated parameters to the terminal display feedback unit in real time. The terminal display feedback unit is used to display real-time data, provide voice feedback, and generate CPR quality reports.

[0008] Preferably, the flexible pressure sensing array adopts a 3×3 matrix design, consisting of two layers of polyimide substrate, a middle carbon nanotube / polydimethylsiloxane piezoresistive sensing layer, and silver paste electrodes.

[0009] Preferably, the main control processing unit calculates the compression depth by: performing a double integral on the acceleration signal to obtain the initial displacement, and calibrating the initial displacement using the peak moment of the pressure signal to obtain the corrected compression depth.

[0010] in, and The calibration coefficient is automatically fitted using data from 3-5 effective presses of the initial press.

[0011] Preferably, the main control processing unit evaluates the integrity of chest wall rebound using three indicators: rebound rate, rebound time, and residual pressure. The rebound rate is the ratio of the maximum displacement of chest wall rebound during the compression and release phase to the compression depth. When the rebound rate is ≥95%, it is determined to be a complete rebound.

[0012] Preferably, the terminal display feedback unit includes a personalized strategy recommendation module, used to generate a recommended range of compression depth and frequency based on the patient's age, weight, and initial chest wall compliance; the initial chest wall compliance is the ratio of the average depth of the initial compression to the average peak pressure.

[0013] Preferably, the terminal display feedback unit adopts a graded voice feedback mechanism, which issues voice prompts of different urgency levels according to the degree of deviation in the compression quality; the prompts include too deep, too shallow, too fast, too slow, and incomplete chest wall rebound.

[0014] Preferably, the wireless communication module adopts the Bluetooth Low Energy 5.0 protocol; the data frame includes device ID, timestamp, press depth, press frequency, rebound rate, residual pressure and status code.

[0015] Preferably, the wearable sensing unit is powered by a 3V button battery.

[0016] Preferably, the terminal display feedback unit can be integrated into an automated external defibrillator (AED) or bedside monitor, and upload CPR quality data to the hospital information system or central monitoring station via a Wi-Fi network.

[0017] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: 1. Significantly improved measurement accuracy: Utilizing pressure-acceleration dual-modal fusion technology, the pressure depth measurement error is ≤±0.3cm, far superior to ±1.5cm for a single accelerometer. It can also accurately identify whether the pressure position is correct, avoiding invalid pressure.

[0018] 2. More comprehensive assessment dimensions: For the first time, quantitative assessment of chest wall rebound integrity has been achieved, filling a gap in existing technology. It can simultaneously monitor six key indicators: compression depth, frequency, compression-release ratio, rebound rate, rebound time, and residual pressure, comprehensively assessing the quality of CPR.

[0019] 3. More scientific compression strategies: Personalized compression strategies are generated based on individual patient parameters, avoiding insufficient or excessive compression caused by uniform standards. This significantly improves the effectiveness and safety of compression, especially for children, obese patients, and elderly patients.

[0020] 4. More timely and effective feedback: A tiered voice feedback mechanism provides different levels of urgency based on the degree of deviation. Medical staff can receive clear operational instructions without shifting their gaze, making it more practical in tense rescue environments.

[0021] 5. Data Traceability and Analysis: Completely records data throughout the entire CPR process, generating standardized quality reports. This provides objective and accurate data support for improving emergency care quality, providing evidence in medical disputes, and training personnel.

[0022] 6. Easy to operate and widely applicable: The wearable sensing unit is disposable, easy to attach, and does not affect the pressing operation. The terminal device is compatible with multiple platforms such as smartphones, AEDs, and monitors, and is suitable for various scenarios such as pre-hospital emergency care, emergency resuscitation rooms, and ICUs.

[0023] 7. Low power consumption design and long battery life: With low power consumption hardware and optimized power management strategy, a disposable button battery can support more than 8 hours of continuous operation, meeting the needs of a single emergency rescue. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the device structure of the present invention; Figure 2 This is a schematic diagram of the application control logic of the device of the present invention. Detailed Implementation

[0026] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0027] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0028] In the embodiments of this invention, the terms "image" and "picture" may sometimes be used interchangeably. It should be noted that, without emphasizing the distinction between them, they convey the same meaning. Similarly, the terms "of," "corresponding (relevant)," and "corresponding" may sometimes be used interchangeably. It should be noted that, without emphasizing the distinction between them, they convey the same meaning.

[0029] In this embodiment of the invention, sometimes a subscript such as W1 may be mistakenly written as a non-subscript form such as W1. When the difference is not emphasized, the meaning they express is the same.

[0030] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0031] To overcome the technical deficiencies of existing technologies, this application develops a real-time monitoring device for cardiopulmonary resuscitation (CPR) quality that features high measurement accuracy, comprehensive assessment, timely feedback, and the ability to provide personalized compression strategies. This device has significant clinical and social value for improving CPR quality and increasing the resuscitation success rate of cardiac arrest patients.

[0032] This device employs a dual-modal fusion of a flexible pressure sensor array and a triaxial accelerometer. By calibrating the acceleration integral error using a Kalman filter algorithm, the accuracy of compression depth measurement is improved from the traditional ±1.5cm to ±0.3cm. It innovatively proposes a chest wall rebound assessment model based on the pressure-displacement curve, which achieves real-time objective assessment of chest wall rebound integrity through three quantitative indicators: rebound rate, rebound time, and residual pressure. A multiple linear regression prediction model is established, which dynamically generates personalized compression parameter recommendations by combining patient age, weight, and initial chest wall compliance data.

[0033] Specifically, the core technical improvements of this invention are as follows: 1. Pressure-Acceleration Dual-Mode Fusion Measurement Technology: For the first time, flexible pressure sensing is combined with triaxial acceleration sensing. The pressure signal triggers the pressing event and calibrates the acceleration integration error, improving the pressing depth measurement accuracy from ±1.5cm to ±0.3cm. This completely solves the problems of baseline drift and pressing angle interference of a single acceleration sensor.

[0034] 2. Quantitative assessment technology for chest wall rebound integrity: A chest wall rebound assessment algorithm based on pressure-displacement curves is proposed, defining three quantitative indicators: rebound rate, rebound time, and residual pressure, to achieve real-time and objective assessment of chest wall rebound integrity, filling the gap in existing technologies.

[0035] 3. Personalized Compression Strategy Dynamic Recommendation Technology: Establish a compression parameter prediction model based on the patient's age, weight, and initial chest wall compliance. It can automatically adjust the recommended compression depth and frequency range according to individual patient differences, avoiding insufficient or excessive compression caused by uniform standards.

[0036] 4. Multi-dimensional real-time voice feedback technology: A graded voice feedback mechanism is designed to provide voice prompts of different levels of urgency based on the degree of deviation in the quality of the compression, and combined with dynamic graphic display, so that medical staff can obtain clear operation guidance without taking their eyes off the subject.

[0037] 5. Full-process data recording and analysis technology: The device can continuously record the compression parameters, time points and intervention measures of the entire CPR process, and generate standardized CPR quality reports, providing objective data support for emergency care quality improvement, medical dispute evidence collection and personnel training.

[0038] As shown in Figure 1, the real-time feedback device for cardiopulmonary resuscitation quality and chest compression depth monitoring of the present invention mainly consists of two parts: a wearable sensing unit and a terminal display feedback unit. The wearable sensing unit is a disposable flexible patch that integrates all data acquisition and preprocessing functions. The terminal display feedback unit can be a smartphone, tablet computer, AED device, or monitor, and is responsible for data display, voice feedback, and data storage.

[0039] Its design features are: The device comprises a flexible pressure-sensing patch, a multi-axis accelerometer module, a main control processing unit, a wireless communication module, a voice feedback module, and a mobile terminal application. The flexible pressure-sensing patch is attached to the lower third of the patient's sternum to collect compression pressure signals in real time. The multi-axis accelerometer module is integrated within the patch to simultaneously collect three-dimensional acceleration signals of the chest wall. The main control processing unit uses a Kalman filter algorithm to fuse pressure and acceleration data, accurately calculating compression depth, frequency, compression-release ratio, and chest wall rebound integrity. Data is transmitted in real time to the mobile terminal or AED display via Bluetooth Low Energy. The system generates personalized compression strategies based on individual patient parameters (age, weight, initial chest wall compliance) and provides real-time voice prompts indicating whether compressions are too deep, too shallow, too fast, too slow, or incomplete rebound. The device can completely record data throughout the entire CPR process, supporting post-operative playback and analysis. This invention solves the problems of low measurement accuracy, incomplete assessment, and untimely feedback in existing technologies. It is applicable to various scenarios such as pre-hospital emergency care and emergency resuscitation rooms, and can significantly improve the quality of CPR and the success rate of resuscitation.

[0040] The following section will detail the two components: the wearable sensing unit and the terminal display feedback unit.

[0041] I. Wearable Sensing Unit The wearable sensing unit is the core of this device. It features a flexible substrate design, with a thickness ≤1mm and a weight ≤5g, allowing it to fit snugly against the patient's chest wall without interfering with chest compressions. Its internal components include: 1. Flexible pressure sensor array The flexible pressure sensing array consists of two flexible polyimide (PI) substrates, a middle piezoresistive sensing layer, and silver paste electrodes. The piezoresistive sensing layer is made of carbon nanotube / polydimethylsiloxane (CNT / PDMS) composite material with a thickness of 50 μm, exhibiting good flexibility and piezoresistive properties. The sensing array uses a 3×3 matrix design, with an effective sensing area of ​​5 cm × 5 cm, which can cover the standard pressing area.

[0042] The operating conditions of the flexible pressure sensor array are: pressure measurement range 0-600N, resolution 1N, response time ≤10ms, linearity ≥95%, and repeatability ≥98%.

[0043] When pressure is applied to the sensor array, the resistance of the CNT / PDMS composite material decreases as the pressure increases. By measuring the resistance change of each sensor unit, the total pressure and the center of pressure distribution can be calculated, thereby determining whether the pressing position is correct.

[0044] 2. Three-axis accelerometer module The three-axis accelerometer module can use, for example, the Analog Devices ADXL345 three-axis digital accelerometer, which integrates a 16-bit ADC, has a measurement range of ±16g, and a sampling frequency of 100Hz. It is used to acquire real-time three-dimensional acceleration signals of the chest wall during chest compressions to calculate compression depth and trajectory. It can be fixed at the center of a flexible pressure sensor array, coaxial with the compression point, ensuring that the acceleration measurement direction is consistent with the compression direction.

[0045] 3. Main Control Processing Unit (MCU) As the control center of the device, the MCU can perform the following core control functions: a. Simultaneously acquire raw data from the pressure sensor array and the accelerometer; b. Perform data preprocessing, filtering, and fusion algorithms; c. Calculate compression depth, frequency, compression-release ratio, and chest wall rebound index. Below are some examples of calculation methods. (1) Accurate calculation of pressing depth The compression depth is obtained by combining the second integral of acceleration with the pressure signal for calibration. The specific calculation process is as follows: Acceleration signal preprocessing: The raw acceleration signal is subjected to Butterworth low-pass filtering (cutoff frequency 20Hz) to remove high-frequency noise. Then, high-pass filtering (cutoff frequency 0.5Hz) is used to eliminate the effects of gravitational acceleration and baseline drift.

[0046] Press event trigger: When the pressure detected by the pressure sensor array exceeds the threshold (50N), it is determined that the press has started; when the pressure drops below the threshold, it is determined that the press has ended.

[0047] Displacement integral calculation: During the pressing cycle, the acceleration signal is calculated... The velocity is obtained by performing a first integration, and the displacement is obtained by performing a second integration. , ,in, and The initial velocity and initial displacement at the start of pressing are both set to 0.

[0048] Pressure signal calibration: Due to the cumulative error in acceleration integration, this invention uses the peak moment of the pressure signal to calibrate the displacement. At the peak pressure moment of each pressing cycle, the displacement should reach its maximum value (i.e., pressing depth). By establishing a calibration model of pressure peak and pressing depth, the displacement obtained by integration is corrected.

[0049] in, and The calibration coefficient is automatically fitted using data from 3-5 effective presses of the initial press.

[0050] (2) Assessment of chest wall rebound integrity Chest wall rebound integrity is assessed using the following three quantitative indicators: Rebound rate (RR): defined as the maximum displacement of the chest wall rebounding during the compression-release phase. With pressure depth The ratio:

[0051] Rebound assessment (the threshold here can be set by medical staff or industry standards): When RR ≥ 95%, it is judged as complete chest wall rebound; when 80% ≤ RR < 95%, it is judged as incomplete rebound; when RR < 80%, it is judged as severe insufficient rebound.

[0052] Rebound time (RT): Defined as the time required for the chest wall to rebound to its initial position from the maximum compression depth. A normal rebound time should be ≤150ms; if RT>200ms, it indicates slow chest wall rebound.

[0053] Residual pressure (RP): Defined as the remaining pressure detected by the pressure sensor array at the end of the compression-release phase. If RP > 20N, it indicates that the rescuer's hands have not completely left the patient's chest wall.

[0054] The system integrates the above three indicators to give a comprehensive score for chest wall rebound integrity, and provides voice prompts to rescuers to adjust their compression techniques.

[0055] d. Control the data transmission of the wireless communication module; e. Manage power supply to achieve low-power operation.

[0056] The main control chip can be, for example, STMicroelectronics' STM32L431 low-power microcontroller, which has an ARM Cortex-M4 core, a clock frequency of 80MHz, and built-in 256KB Flash and 64KB SRAM.

[0057] 4. Wireless communication module The wireless communication module can be, for example, the nRF52832 Bluetooth Low Energy (BLE) module, which supports the Bluetooth 5.0 protocol, has a transmission distance of ≥10m, and a peak power consumption of ≤5mA.

[0058] The wireless communication module uses a custom application-layer communication protocol with a data transmission rate of 115200bps, transmitting one frame of data every 100ms, including key parameters such as compression depth, frequency, and rebound rate. It is used to transmit processed CPR quality data to the terminal display and feedback unit in real time, and to receive patient parameters and control commands from the terminal.

[0059] 5. Power Management Module The power supply uses a 3V button battery (CR2032) with a capacity of 225mAh. It supports sleep mode and wake-up mode, with standby current ≤1μA, operating current ≤10mA, and continuous working time ≥8 hours, meeting the needs of a single emergency rescue.

[0060] II. Terminal Display Feedback Unit The terminal display feedback unit is developed based on Android or iOS systems and can run on smartphones, tablets, or be integrated into AEDs / monitors. Its main functional modules include: Patient information entry module: Supports the entry of patient information such as age, gender, weight, and underlying diseases, providing a basis for personalized compression strategies.

[0061] Real-time data display module: Displays the current compression depth, frequency, compression-release ratio, and chest wall rebound rate in real time in both digital and graphical formats, and uses different colors to indicate the target status (green = target, yellow = warning, red = non-target).

[0062] Voice feedback module: Using TTS speech synthesis technology, it provides real-time voice prompts based on the deviation in the quality of the compression, such as "The compression is too shallow, please deepen it to 5-6cm" and "The chest wall has not fully rebounded, please relax".

[0063] Personalized strategy recommendation module: Based on patient parameters and initial compression data, dynamically adjusts the recommended compression depth and frequency range. For example, by establishing a compression parameter prediction model based on multiple linear regression, the input variables include patient age (…). ),weight( ) and initial chest wall compliance ( Initial chest wall compliance was calculated using data from the first three effective chest compressions.

[0064] in, This represents the average depth of the first three presses. This represents the average peak pressure of the first three presses.

[0065] Recommended pressing depth ( ) and recommended press frequency ( The calculation formula for ) is as follows: , , The recommended parameters output by the model must meet the basic requirements of the AHA guidelines: for adults, It should be within the range of 5-6cm. It should be in the range of 100-120 beats / minute; for children, It should be within the range of 4-5cm; for infants, The value should be within 3-4 cm. If the model output exceeds this range, the boundary value should be taken as the recommended value.

[0066] Data recording and analysis module: Completely records all parameters and time points of the entire CPR process, and supports data playback, statistical analysis and report generation.

[0067] Data sharing module: Supports uploading CPR quality reports to the Hospital Information System (HIS) or emergency center platform via Bluetooth, Wi-Fi or 4G network.

[0068] III. Data Communication and Application Control Instructions for the Device 1. Data communication process This device adopts a master-slave communication architecture, with the wearable sensing unit as the slave device and the terminal display feedback unit as the master device. The data communication process is as follows: Device pairing and connection: The terminal device scans and discovers nearby wearable sensing units and establishes a connection via Bluetooth. After successful connection, the terminal sends a synchronization command to the sensing unit to initialize the system time.

[0069] Patient parameter transmission: After medical staff enter patient information into the terminal, the terminal sends parameters such as the patient's age and weight to the sensing unit.

[0070] Real-time data transmission: The sensing unit sends one data frame to the terminal every 100ms. The data frame format is shown in the table below: 0xAA 2 bytes 4 bytes 1 byte 1 byte 1 byte 1 byte 1 byte 1 byte 0x55 Control command transmission: The terminal can send control commands such as start acquisition, stop acquisition, and calibration to the sensing unit. The sensing unit executes the corresponding operation and returns confirmation information.

[0071] Disconnection: After CPR is completed, the terminal sends a disconnection command to the sensing unit, and the sensing unit enters sleep mode.

[0072] 2. Application control logic like Figure 2 As shown, the application control logic of the device adopts a state machine design, including four states: standby state, ready state, monitoring state, and end state. The state transition process is as follows: Standby mode: After the device is powered on, it enters standby mode. At this time, the power management module shuts down most peripherals and only retains the Bluetooth broadcast function, waiting for the terminal to connect.

[0073] Ready State: After successfully connecting to the terminal, the device enters the ready state. At this time, the sensing unit begins collecting pressure and acceleration data, but does not calculate pressure parameters. After medical staff affix the patch and enter patient information, they click the "Start Monitoring" button on the terminal, and the device enters monitoring mode.

[0074] Monitoring Status: This is the core operating status of the device. The sensing unit collects and processes data in real time, calculates the pressing parameters, and sends them to the terminal. The terminal displays the received data in real time and provides voice feedback. If no pressing action is detected for 10 consecutive seconds, the terminal will issue a prompt saying "Please continue pressing."

[0075] End Status: After CPR is completed, healthcare workers click the "End Monitoring" button on the terminal, and the device enters the end status. At this time, the sensing unit stops data acquisition, and the terminal generates a CPR quality report and saves the data. Users can choose to replay the data, print the report, or upload it to the hospital information system.

[0076] IV. Instructions for Use of the Device The standard application procedure for this device is as follows: Device preparation: Remove the disposable wearable sensing unit and check that the packaging is intact. Tear off the protective film on the back and attach the patch to the lower 1 / 3 of the patient's sternum (midpoint of the line connecting the two nipples), ensuring that the patch adheres tightly to the skin without air bubbles or wrinkles.

[0077] Device connection: Open the application on the terminal device, click "Connect Device", scan and select the corresponding sensor unit ID, and establish a Bluetooth connection.

[0078] Patient Information Entry: Enter the patient's basic information such as age, gender, and weight in the application. If the information is incomplete, the system will default to using standard adult parameters.

[0079] Initial Calibration: Click the "Start Calibration" button, and the system will automatically perform 3 initial compression calibrations. The rescuer performs 3 compressions using the standard technique, and the system will calculate the initial chest wall compliance based on the compression data and generate a personalized compression strategy recommendation.

[0080] Real-time monitoring and feedback: After calibration, click "Start Monitoring" to enter real-time monitoring mode. The rescuer performs chest compressions according to the system's recommended parameters, and the system will provide real-time feedback on the compression quality via voice and graphics. If the compression parameters are not up to standard, the system will issue corresponding voice prompts to guide the rescuer in adjusting their technique.

[0081] Data recording and saving: During CPR, the system will automatically record all compression parameters and time points. If you need to pause compressions, you can click the "Pause" button to stop data recording.

[0082] End of CPR and Report Generation: After CPR is completed, click the "End Monitoring" button. The system will automatically generate a CPR quality report, including key indicators such as compression depth achievement rate, frequency achievement rate, rebound integrity score, and compression interruption time. The report can be saved locally or uploaded to the hospital information system.

[0083] Device disposal: After use, the wearable sensing unit shall be disposed of in accordance with the medical waste disposal regulations, and the terminal equipment shall be cleaned and disinfected before being put into use.

[0084] Example 1: Pre-hospital emergency care scenario This device is integrated into commercially available AED devices as a standard configuration module. Each AED is equipped with 10 disposable wearable sensor units, stored in a dedicated storage compartment within the AED housing. Emergency responders can quickly retrieve the sensor units and attach them to the patient's chest wall upon arrival at the scene. The AED device itself serves as a terminal display and feedback unit, integrating the application of this invention, eliminating the need for an additional smartphone or tablet.

[0085] Implementation process: Scene situation: The patient was a 58-year-old male, weighing 75kg, who suddenly suffered cardiac arrest while walking in the park. Passersby called 120 for emergency medical assistance, and paramedics arrived at the scene with an AED 5 minutes later.

[0086] Device Deployment: Emergency responders should immediately lay the patient supine on a flat surface, loosen their clothing, remove the wearable sensor unit, and attach it to the lower third of the patient's sternum. Turn on the AED; the AED will automatically scan and connect to the sensor unit.

[0087] Patient information entry: Emergency responders quickly enter the patient's age as 58 years old and weight as 75 kg on the AED screen.

[0088] Initial calibration: The AED prompts "Please perform 3 initial compressions." Rescuers perform 3 compressions using standard techniques. The system calculates an initial chest wall compliance of 2.2 mm / N, a recommended compression depth of 5.3 cm, and a recommended compression rate of 108 compressions / min.

[0089] Real-time monitoring and feedback: The AED enters real-time monitoring mode, displaying the current compression depth, frequency, and rebound rate on the screen. The rescuer begins chest compressions; the first few compressions are approximately 4.5cm deep, and the AED immediately issues a voice prompt: "Compression too shallow, please deepen to 5-5.6cm." After the rescuer adjusts the compression depth, it stabilizes between 5.2-5.5cm. During compressions, the system detects a chest wall rebound rate of 88% and issues a prompt: "Chest wall not fully rebounded, please relax your hand." After the rescuer adjusts their technique, the rebound rate recovers to over 96%.

[0090] Defibrillation and Resuscitation: After analyzing the heart rhythm, the AED indicated that defibrillation was necessary, and the emergency responders performed defibrillation as instructed. Following defibrillation, CPR continued, with the device continuously monitoring the quality of compressions. The entire resuscitation process lasted 25 minutes, with a total interruption of 45 seconds in compressions.

[0091] Resuscitation Results: Compared with traditional pre-hospital emergency care without this device, the technical advantages of this embodiment are shown in the table below: Pressing depth compliance rate 52% 96% +84.6% Pressing frequency compliance rate 48% 94% +95.8% Chest wall rebound rate 45% 92% +104.4% Total time of press interruption 120 seconds 45 seconds -62.5% Out-of-hospital resuscitation success rate 1.2% 2.8% +133.3% The patient regained spontaneous heartbeat and breathing and was transported to the hospital for further treatment. The AED automatically generated a CPR quality report, showing a 96% success rate in achieving the target compression depth, a 94% success rate in achieving the target compression rate, and a 92% complete chest wall recoil rate. This represents a significant improvement over traditional first aid methods.

[0092] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A device for real-time feedback of cardiopulmonary resuscitation quality and monitoring of chest compression depth, characterized in that, Includes wearable sensing units and terminal display feedback units; The wearable sensing unit includes a flexible pressure sensor array, a three-axis accelerometer module, a main control processing unit, and a wireless communication module. The flexible pressure sensor array is used to acquire compression pressure signals in real time, and the three-axis accelerometer module is used to synchronously acquire three-dimensional acceleration signals of the chest wall. The main control processing unit uses a Kalman filter algorithm to fuse pressure and acceleration data to calculate compression depth, frequency, compression-release ratio, and chest wall rebound integrity index. The wireless communication module transmits the calculated parameters to the terminal display feedback unit in real time. The terminal display feedback unit is used to display real-time data, provide voice feedback, and generate CPR quality reports.

2. The apparatus according to claim 1, characterized in that, The flexible pressure sensing array adopts a 3×3 matrix design, consisting of two polyimide substrates, a middle carbon nanotube / polydimethylsiloxane piezoresistive sensing layer, and silver paste electrodes.

3. The apparatus according to claim 1, characterized in that, The main control processing unit calculates the compression depth as follows: The initial displacement is obtained by performing a double integral on the acceleration signal; the initial displacement is then calibrated using the peak value of the pressure signal to obtain the corrected compression depth. in, and The calibration coefficient is automatically fitted using data from 3-5 effective presses of the initial press.

4. The apparatus according to claim 1, characterized in that, The main control processing unit evaluates the integrity of chest wall rebound using three indicators: rebound rate, rebound time, and residual pressure. The rebound rate is the ratio of the maximum displacement of chest wall rebound during the compression and release phase to the compression depth. When the rebound rate is ≥95%, it is determined to be a complete rebound.

5. The apparatus according to claim 1, characterized in that, The terminal display feedback unit includes a personalized strategy recommendation module, which generates a recommended range of compression depth and frequency based on the patient's age, weight, and initial chest wall compliance; the initial chest wall compliance is the ratio of the average depth of the initial compression to the average peak pressure.

6. The apparatus according to claim 1, characterized in that, The terminal display feedback unit adopts a graded voice feedback mechanism, which issues voice prompts of different urgency levels according to the degree of deviation in the quality of the compression; the prompts include too deep, too shallow, too fast, too slow and incomplete chest wall rebound.

7. The apparatus according to claim 1, characterized in that, The wireless communication module uses the Bluetooth Low Energy 5.0 protocol; the data frame includes device ID, timestamp, press depth, press frequency, rebound rate, residual pressure and status code.

8. The apparatus according to claim 1, characterized in that, The wearable sensing unit is powered by a 3V button battery.

9. The apparatus according to claim 1, characterized in that, The terminal display feedback unit can be integrated into an automated external defibrillator (AED) or bedside monitor, and upload CPR quality data to the hospital information system or central monitoring station via a Wi-Fi network.

10. The application of the device according to claim 1 in the preparation of cardiopulmonary resuscitation assistive devices, characterized in that, The application scenarios include pre-hospital emergency care, emergency resuscitation rooms, intensive care units, and first aid training.

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