Automatic external defibrillator with self-adaptive fitting and monitoring functions

Abstract

The invention relates to an automatic external defibrillator with self-adaptive fitting and monitoring functions, and relates to the field of medical instruments, the automatic external defibrillator comprises a host and an electrode slice, the electrode slice is connected with the host through a transmission cable, the electrode slice is composed of a three-layer structure, and a plurality of air bags are arranged on the top layer of the electrode slice at intervals; one side outside the transmission cable is fixedly connected with an air pipe which communicates with the airbag and the host; a temperature sensor is arranged in the middle of the electrode slice bottom layer, film pressure sensors are arranged on the electrode slice bottom layer in the four corner directions of the temperature sensor, long-strip-shaped film potentiometers are arranged at the four corners of the electrode slice bottom layer, and the temperature sensor, the film pressure sensors and the film potentiometers are electrically connected with a host through transmission cables. According to the invention, the contact state of the electrode plate and the skin of the patient and the physiological parameters of the patient can be monitored in real time by the host. The method has the advantages of autonomously adjusting the attaching effect of the electrode plate and adjusting the defibrillation strategy.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an automated external defibrillator with adaptive fitting and monitoring functions. Background Technology

[0002] Automated external defibrillators (AEDs) are crucial emergency medical devices that play a vital role in situations such as cardiac arrest. However, existing AEDs have some shortcomings in terms of electrode fit against the patient's body and real-time monitoring of fit and the patient's physiological parameters: 1. Currently, common electrode pad materials are limited, mostly using ordinary rubber or plastic bases, with an elastic modulus generally >50MPa. This makes them unsuitable for patients with chest wall curvature >15°, posing a risk of poor contact.

[0003] 2. Existing automated external defibrillators (AEDs) lack real-time and effective monitoring of electrode pad fit, making it impossible to promptly detect issues such as electrode pad loosening or displacement. Even if other medical electrode pads have loosening detection functions, they generally use a single sensor, which cannot accurately identify local loosening and displacement. For example, if only a pressure sensor is used, and the local pressure momentarily rises to 20 kPa during emergency compressions but drops sharply after release, it is easily misjudged as loosening. Or, if only a displacement sensor is used, the chest rise and fall during breathing may cause the electrode pad edge to shift by 1.5 mm, which does not reach the 2 mm alarm threshold, but the actual pressure remains at 10 kPa, easily misjudged as a proper fit.

[0004] 3. Currently, AEDs lack physiological parameter monitoring, with only some high-end models connected to external blood oxygen interfaces or thermometers. This not only leads to high prices for defibrillators but also indirectly raises the professional threshold for users, making it difficult for most ordinary people to operate them conveniently and achieve the goal of timely saving lives.

[0005] Therefore, to address the above shortcomings, there is a need to provide an automated external defibrillator with adaptive fitting and monitoring functions. Summary of the Invention

[0006] (a) Technical problems to be solved The technical problem to be solved by the present invention is to address the issues of poor electrode patch adhesion, insufficient monitoring of adhesion status, and incomplete monitoring of patient physiological parameters in the prior art.

[0007] (II) Technical Solution To address the aforementioned technical problems, this invention provides an automated external defibrillator (AED) with adaptive fit and monitoring functions, comprising a main unit and electrode pads. The electrode pads are connected to the main unit via transmission cables. The electrode pads consist of a three-layer structure. The top layer of the electrode pads has several air bladders spaced apart. An air tube is fixed to one side of the transmission cable, connecting the air bladders and the main unit. A temperature sensor is located in the middle of the bottom layer of the electrode pads. Thin-film pressure sensors are located at the four corners of the temperature sensor on the bottom layer of the electrode pads. Elongated thin-film potentiometers are located at the four corners of the bottom layer of the electrode pads. The temperature sensor, thin-film pressure sensor, and thin-film potentiometer are electrically connected to the main unit via transmission cables, enabling the main unit to monitor the contact status between the electrode pads and the patient's skin and the patient's physiological parameters in real time.

[0008] As a further explanation of the present invention, preferably, the electrode sheet has a long strip structure and the periphery of the electrode sheet is wavy.

[0009] As a further explanation of the present invention, preferably, the elongated thin-film potentiometers are radially distributed, with the head of the thin-film potentiometer extending to the wavy protruding end of the electrode plate.

[0010] As a further explanation of the present invention, preferably, the thin-film pressure sensor is in the shape of a disc, and the thin-film pressure sensors are distributed radially.

[0011] As a further explanation of the present invention, preferably, the temperature sensor is a thin-film platinum resistance temperature sensor, and the contact pressure between the temperature sensor and the patient's skin is less than 5 kPa to ensure heat conduction efficiency.

[0012] As a further explanation of the present invention, preferably, the three-layer electrode sheet consists of a base layer, a conductive layer and a functional layer from top to bottom. The base layer is made of medical-grade liquid silicone, and several airbags are arranged in an array at intervals within the base layer. The airbags are made of medical polyurethane film.

[0013] As a further explanation of the present invention, preferably, airways are provided between the plurality of airbags so that the airbags are interconnected and the airways are connected to the trachea.

[0014] As a further explanation of the present invention, preferably, an alternating current is passed through the conductive layer to detect the skin impedance value.

[0015] As a further explanation of the present invention, preferably, the temperature sensor, the thin-film pressure sensor, and the thin-film potentiometer are all located within the functional layer, and the functional layer is in contact with the patient's skin; the host analyzes the data from the thin-film pressure sensor and the thin-film potentiometer to control whether the airbag starts working; the host analyzes the skin impedance data and the thin-film pressure sensor data to control the inflation or deflation volume of the airbag; and the host analyzes the skin impedance data and the temperature sensor data to control the current energy.

[0016] As a further explanation of the present invention, preferably, when the pressure fluctuation rate fed back by the thin-film pressure sensor is >5kPa / s and the displacement fluctuation rate fed back by the thin-film potentiometer is <0.5mm / s, it is determined to be a pressing interference and no adjustment is triggered; when the pressure is continuously <8kPa and the displacement is continuously >1mm, it is determined to be a true fit failure, and the host controls the airbag to inflate. When the skin resistance Z > 2000Ω and the pressure value P of the membrane pressure sensor < 8kPa: increase the air pressure of the cuff by 5kPa, and at the same time increase the defibrillation energy from 150J to 200J; when the temperature value T fed back by the temperature sensor < 32℃ and the skin resistance Z < 500Ω, the main unit indicates the risk of hypothermia and reduces the energy by 10% to avoid myocardial damage to the patient.

[0017] (III) Beneficial Effects The above-described technical solution of the present invention has the following advantages: 1. The adaptive fitting electrode pad designed in this invention can make better contact with the patient's skin, with a fitting rate of more than 90%, which improves the uniformity of defibrillation current and thus helps to improve the success rate of defibrillation.

[0018] 2. The built-in fit status monitoring system of the present invention can detect abnormalities of the electrode pads in a timely manner, avoiding defibrillation failure due to loose or displaced electrode pads. Furthermore, through the combination of multiple sensors, the monitoring reliability is improved. For example, the false alarm rate of pressure / displacement monitoring is <0.1%, and the accuracy of temperature / impedance data meets the monitoring requirements of ICU level. This function can provide doctors with more accurate physiological information of patients, which helps to comprehensively assess the patient's condition and formulate more reasonable treatment plans.

[0019] 3. The intelligent control and data analysis system built into the main unit of this invention can automatically adjust the defibrillation strategy according to the patient's real-time data, avoid excessive energy output, and enable ordinary people to quickly use it to treat patients without professional operating skills, thereby realizing intelligent and personalized treatment and improving the quality of medical services. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a top view of the electrode sheet of the present invention; Figure 3 This is a structural diagram of the airbag of the present invention; Figure 4 This is a side view of the electrode sheet of the present invention; Figure 5 This is a bottom view of the electrode sheet of the present invention; Figure 6 This is a sensor distribution diagram of the present invention; Figure 7 This is a diagram of the electrode sheet structure of the present invention.

[0021] In the diagram: 1. Main unit; 2. Electrode plate; 21. Substrate layer; 22. Conductive layer; 23. Functional layer; 3. Airbag; 31. Airway; 4. Temperature sensor; 5. Thin-film pressure sensor; 6. Thin-film potentiometer; 7. Transmission cable; 71. Air tube; 8. Adapter. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] An automated external defibrillator with adaptive fit and monitoring functions, combined with Figure 1 , Figure 2 The device includes a main unit 1 and electrode pads 2, with the electrode pads 2 connected to the main unit 1 via a transmission cable 7. The main unit 1 contains necessary electronic components such as a battery, display screen, start / stop button, and controller. The main unit 1 can be placed on a table, stand, or floor, and the electrode pads 2 are attached to the patient's chest skin.

[0024] Combination Figure 3 , Figure 7 The electrode pad 2 is a long strip structure composed of three layers. The electrode pad has a wavy edge, which increases the contact area between the electrode pad 2 and the skin. Simultaneously, during patient movement, the wavy edge better adapts to the stretching and deformation of the skin, reducing the possibility of the electrode pad 2 loosening. From top to bottom, the electrode pad 2 consists of a base layer 21, a conductive layer 22, and a functional layer 23, with the functional layer 23 adhering to the patient's skin. The base layer 21 is preferably made of medical-grade liquid silicone with a Shore hardness of 30A and an elongation at break >800%. It contains several airbags 3 arranged in an array. The airbags 3 are made of medical-grade polyurethane film. An air tube 71 is fixed to one side of the transmission cable 7, connecting the airbags 3 and the main unit 1. Airways 31 are provided between the airbags 3 to allow them to communicate with each other, and the airways 31 are connected to the air tubes 71. The low-modulus base layer 21 can not only adapt to complex thoracic structures without skin irritation, but also cause the base layer 21 to fold downwards around its perimeter when the airbag 3 inflates in the middle of the base layer 21, thereby controlling the electrode pads 2 to adhere to the skin around their perimeter and achieving automatic adhesion.

[0025] Combination Figure 5 , Figure 6The conductive layer 22 in the middle of electrode pad 2 is used for outputting current. Simultaneously, by applying a weak alternating current to the skin, the current response through the skin is measured, and the host unit 1 can calculate the skin's impedance value. A temperature sensor 4 is located in the middle of the functional layer 23 at the bottom of electrode pad 2. The temperature sensor 4 is preferably a thin-film platinum resistance temperature sensor, and the contact pressure between the temperature sensor 4 and the patient's skin is less than 5 kPa to ensure efficient heat conduction. Thin-film pressure sensors 5 are located on the bottom layer of electrode pad 2 at the four corners of the temperature sensor 4. The thin-film pressure sensors 5 are circular and acquire pressure information by converting the pressure applied to the FSR sensor film area into a change in resistance. The thin-film pressure sensors 5 are radially distributed. Elongated thin-film potentiometers 6 are located at the four corners of the bottom layer of electrode pad 2, radially distributed, with their heads extending to the wavy protrusions of electrode pad 2. Under external influence, the change in the position of the internal contact point of the thin-film potentiometer 6 causes a change in the ratio of the resistance between the upper and lower resistive films, thus changing the output voltage with the change in external position, which can be used to measure position information. Temperature sensor 4, thin-film pressure sensor 5, and thin-film potentiometer 6 are electrically connected to host 1 via transmission cable 7, so that host 1 can monitor the contact status between electrode 2 and patient skin and patient physiological parameters in real time.

[0026] Combination Figure 2 , Figure 4 A transition platform 8 is provided between the electrode plate 2 and the transmission cable 7. The transition platform 8 has a channel for connecting the cables to various sensors, as well as for connecting the air tube 71 and the airway 31, ensuring a stable connection between the thin electrode plate 2 and the thick transmission cable 7 and air tube 71, without affecting the performance of the electrode plate 2. The transmission cables 7 and air tubes 71 on the two sets of electrode plates 2 share a connector. The connector has two air holes connected to the two air tubes 71 and multiple interfaces connected to the two transmission cables 7, so that the host 1 can distinguish and control them.

[0027] The main unit 1 is equipped with a skin impedance monitoring circuit. A weak, high-frequency current is applied to the patient's skin via electrode pads 2, and the skin's impedance value is measured. Since skin impedance changes with factors such as the patient's physiological state and skin moisture level, real-time monitoring of skin impedance provides doctors with crucial information about the patient's condition. For example, during defibrillation, a sudden increase in skin impedance may indicate poor contact between electrode pads 2 and the skin, or a change in the patient's skin condition, requiring immediate adjustment. The temperature sensor 4 integrated within electrode pads 2 monitors local skin temperature changes in real time. Abnormal temperature changes may reflect internal physiological changes in the patient, such as abnormal local blood circulation.

[0028] The main unit 1 controller has a built-in intelligent control chip that can comprehensively analyze the collected data on electrode pad 2 adhesion, skin impedance, and temperature. Based on this data, the intelligent control chip can automatically adjust the defibrillation strategy, such as adjusting the defibrillation energy output and optimizing the defibrillation waveform, to improve the effectiveness and safety of defibrillation. Specifically: ① When the pressure fluctuation rate fed back by the thin-film pressure sensor 5 is greater than 5 kPa / s and the displacement fluctuation rate fed back by the thin-film potentiometer 6 is greater than or equal to 0.5 mm / s, it is determined to be a pressing interference. No adjustment is triggered, but noise reduction is enhanced by filtering algorithm, and monitoring is continued for 3 seconds. If the displacement is still greater than or equal to 0.5 mm within 3 seconds, the message "The electrode plate is slightly displaced when pressing. It is recommended to fine-tune the pressing gap" is displayed.

[0029] ② When the pressure fluctuation rate fed back by the thin-film pressure sensor 5 is greater than 5 kPa / s and the displacement fluctuation rate fed back by the thin-film potentiometer 6 is less than 0.5 mm / s, it is determined to be a pressing interference and no adjustment is triggered.

[0030] ③ When the pressure fluctuation rate fed back by the thin-film pressure sensor 5 is ≤5kPa / s and the displacement fluctuation rate fed back by the thin-film potentiometer 6 is <0.5mm / s, it is determined to be a stable fit and no adjustment is triggered.

[0031] ④ When the pressure fluctuation rate fed back by the thin-film pressure sensor 5 is ≤5kPa / s and the displacement fluctuation rate fed back by the thin-film potentiometer 6 is ≥0.5mm / s, it is determined that the displacement is not caused by pressing, triggering the "suspected abnormal fit" alarm, and monitoring continues for 2 seconds; if the displacement is still ≥0.5mm within 2 seconds and the pressure does not rise significantly, it is determined that the "actual fit failure" can be controlled at this time.

[0032] ⑤ When the pressure is continuously <8kPa and the displacement is continuously >1mm, it is determined that the true fit has failed, and the host 1 controls the airbag 3 to inflate.

[0033] ⑥ When the pressure is consistently <8kPa and the displacement is consistently ≤1mm, it is determined that the pressure is insufficient but the displacement is not achieved, which is determined as "semi-adhesion failure". The air pressure of the airbag is increased by 3kPa, and the message "Insufficient pressure of electrode sheet, please press to adhere" is displayed. If the pressure is still <8kPa after adjustment, the alarm is upgraded.

[0034] ⑦ When the pressure is ≥8kPa and the displacement is >1mm, it is determined that the pressure is sufficient but the edge is raised, which is determined to be "partial adhesion failure". At this time, the airbag 3 is deflated. If the displacement value is still >1mm, the message "Electrode piece shifted, please re-attach" will be displayed directly.

[0035] In certain special conditions, such as when the skin is dry or the electrode pads 2 are loose, skin impedance increases. The built-in intelligent control system will analyze this immediately: based on the impedance-energy mapping model, it will determine how to adjust the energy based on the increase in impedance. This includes adjusting biphasic waveform parameters—including the first phase peak current and duration; the second phase peak current and duration; and enhancing current penetration depth. Simultaneously, it will increase the air pressure of the cuff 3, etc., to improve the success rate of defibrillation. Specifically: ① When the skin resistance Z > 2000Ω and the pressure value P of the thin-film pressure sensor ≥ 8kPa, it is determined that the resistance is high but the fit is tight. At this time, pressure regulation is not triggered, but only the energy is increased from 150J to 180J and the waveform is optimized, the duration of the first phase is extended by 10%, and the current penetration is enhanced.

[0036] ②When the skin resistance Z > 2000Ω and the pressure value P of the membrane pressure sensor < 8kPa, the air pressure of the airbag is increased by 5kPa, and the defibrillation energy is increased from 150J to 200J.

[0037] ③ When the skin resistance value is 500Ω≤Z≤2000Ω, the pressure value P of the membrane pressure sensor 5 is ≥8kPa, and the temperature value T of the temperature sensor 4 is ≥32℃, it is judged as normal, and the default defibrillation strategy is maintained, that is, energy 150J, standard biphasic wave parameters, and no adjustment is triggered.

[0038] ④ When the skin resistance is 500Ω≤Z≤2000Ω, the pressure value P of the membrane pressure sensor 5 is <8kPa, and the temperature value T of the temperature sensor 4 is ≥32℃, it is determined to be medium resistance and insufficient pressure. The air pressure of the airbag 3 is increased by 4kPa, and the energy is maintained at 150J. If P≥8kPa after adjustment, the default energy is maintained. If P<8kPa, the energy is increased to 160J.

[0039] ⑤ When the skin resistance Z < 500Ω, the pressure value P of the thin-film pressure sensor 5 ≥ 8kPa, and the temperature value T of the temperature sensor 4 ≥ 32℃, it is determined to be low impedance and normal fit. The default energy of 150J is maintained, and the waveform is optimized, such as reducing the first phase peak current by 5% to avoid overstimulating the myocardium.

[0040] ⑥ When the skin resistance Z < 500Ω and the temperature value T fed back by the temperature sensor < 32℃, the host indicates a risk of hypothermia and reduces energy by 10% to avoid myocardial damage to the patient.

[0041] ⑦ When the skin resistance Z > 2000Ω and the temperature T of the temperature sensor 4 < 32℃, increase the air pressure of the airbag 3 by 3kPa and fine-tune the energy to 160J to avoid myocardial damage under hypothermia. At the same time, it indicates "hypothermia + high impedance, it is recommended to quickly adjust the electrode pads".

[0042] ⑧ When the skin resistance value is 500Ω≤Z≤2000Ω and the temperature value T of temperature sensor 4 is <32℃, the energy decreases by 8%, maintaining the standard waveform, indicating "low body temperature risk, closely monitor circulation status".

[0043] In summary, this invention employs a combined design of pressure, displacement, and wireless communication timing synchronization. Four pressure sensors are positioned in the center of the electrode plate for stable detection of the core area, while displacement sensors are placed at the edges to monitor tilting displacement, forming a complementary "pressure + displacement sensitivity" monitoring system. Combined with appropriate filtering algorithms to reduce dynamic interference, this addresses the technical bottleneck of "misjudgment" in dynamic emergency scenarios. Furthermore, the fully automated and visual operation is user-friendly for beginners, allowing more personnel without professional expertise to quickly learn and use the system, responding promptly to sudden patient situations and allowing time for professional physicians to arrive on-site for diagnosis and treatment. The system can also store all collected data, facilitating review and analysis by physicians during subsequent patient treatment, providing a basis for developing personalized treatment plans.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An automated external defibrillator with adaptive fit and monitoring functions, comprising a main unit (1) and electrode pads (2), wherein the electrode pads (2) are connected to the main unit (1) via a transmission cable (7), characterized in that: The electrode pad (2) consists of a three-layer structure. The top layer of the electrode pad (2) is provided with several air bags (3) spaced apart. The transmission cable (7) is fixed to the outside of the air tube (71) and connects the air bags (3) and the host (1) respectively. The bottom layer of the electrode pad (2) is provided with a temperature sensor (4). The bottom layer of the electrode pad (2) is provided with a thin film pressure sensor (5) at the four corners of the temperature sensor (4). The bottom layer of the electrode pad (2) is provided with a long strip-shaped thin film potentiometer (6). The temperature sensor (4), the thin film pressure sensor (5) and the thin film potentiometer (6) are electrically connected to the host (1) through the transmission cable (7) so that the host (1) can monitor the contact status between the electrode pad (2) and the patient's skin and the patient's physiological parameters in real time.

2. An automated external defibrillator with adaptive fit and monitoring functions according to claim 1, characterized in that: The electrode sheet (2) has a long strip structure and the edges of the electrode sheet (2) are wavy.

3. An automated external defibrillator with adaptive fit and monitoring functions according to claim 2, characterized in that: The long strip-shaped thin-film potentiometer (6) is radially distributed, and the head of the thin-film potentiometer (6) extends to the wavy protruding end of the electrode plate (2).

4. An automated external defibrillator with adaptive fit and monitoring functions according to claim 3, characterized in that: The thin-film pressure sensor (5) is circular and radially distributed.

5. An automated external defibrillator with adaptive fit and monitoring functions according to claim 4, characterized in that: The temperature sensor (4) is a thin-film platinum resistance temperature sensor. The contact pressure between the temperature sensor (4) and the patient's skin is less than 5 kPa to ensure heat conduction efficiency.

6. An automated external defibrillator with adaptive fit and monitoring functions according to claim 5, characterized in that: The three-layer electrode sheet (2) consists of a base layer (21), a conductive layer (22), and a functional layer (23) from top to bottom. The base layer (21) is made of medical-grade liquid silicone. Several airbags (3) are arranged in an array and spaced apart in the base layer (21). The airbags (3) are made of medical-grade polyurethane film.

7. An automated external defibrillator with adaptive fit and monitoring functions according to claim 6, characterized in that: An airway (31) is provided between several airbags (3) so that each airbag (3) can be connected to the others, and the airway (31) is connected to the trachea (71).

8. An automated external defibrillator with adaptive fit and monitoring functions according to claim 7, characterized in that: An alternating current is passed through the conductive layer (22) to detect the skin impedance value.

9. An automated external defibrillator with adaptive fit and monitoring functions according to claim 8, characterized in that: Temperature sensor (4), thin-film pressure sensor (5) and thin-film potentiometer (6) are all located in the functional layer (23), which is in contact with the patient's skin; the host (1) analyzes the data from the thin-film pressure sensor (5) and the thin-film potentiometer (6) to control whether the airbag (3) starts working; the host (1) analyzes the skin impedance data and the data from the thin-film pressure sensor (5) to control the inflation or deflation of the airbag (3); the host (1) analyzes the skin impedance data and the data from the temperature sensor (4) to control the current energy.

10. An automated external defibrillator with adaptive fit and monitoring functions according to claim 9, characterized in that: When the pressure fluctuation rate fed back by the thin film pressure sensor (5) is greater than 5 kPa / s and the displacement fluctuation rate fed back by the thin film potentiometer (6) is less than 0.5 mm / s, it is determined to be a pressing interference and no adjustment is triggered; when the pressure is continuously less than 8 kPa and the displacement is continuously greater than 1 mm, it is determined to be a true fit failure and the host (1) controls the airbag (3) to inflate. When the skin resistance Z > 2000Ω and the pressure value P of the membrane pressure sensor (5) < 8kPa: increase the air pressure of the airbag (3) by 5kPa, and at the same time increase the defibrillation energy from 150J to 200J; when the temperature value T fed back by the temperature sensor (4) < 32℃ and the skin resistance Z < 500Ω, the host (1) indicates the risk of low body temperature and reduces the energy by 10% to avoid myocardial damage to the patient.

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