Apex integrated ECG, temperature, respiration, mechanical sensing and alarm device

Abstract

The application discloses a heart apex integrated ECG body temperature and respiration mechanical sensing and alarming device, which comprises a flexible and fitted base suitable for the physiological arc of the fifth rib heart apex and the middle line of the left clavicle, a heart apex mechanical heart rate pulsation sensing component integrated in the center of the base, a thoracic mechanical respiration fluctuation sensing component in the peripheral area and a body temperature detection module in the inner side, and a built-in data processing and wireless transmission module and a local sound and light alarm; the device is pasted on the heart apex, pure mechanical top pressure elastic sheets and telescopic sensing strips are adopted to synchronously collect the body surface heart rate, the respiration frequency and the body temperature, the data is directly transmitted to the nurse mobile nursing PDA in real time, the local sound and light alarm and the PDA end pop-up window vibration alarm are simultaneously triggered when the heart rate is zero or the respiration stops, 24-hour continuous monitoring and on-the-spot immediate response of the critical signal are realized.

Description

Technical Field

[0001] This invention relates to the field of medical vital sign monitoring technology, and in particular to an integrated electrocardiogram, body temperature and respiratory mechanical sensing alarm device at the apex of the heart. Background Technology

[0002] In clinical wards, for patients in the recovery period after surgery, elderly patients with chronic diseases who are bedridden, and hospitalized patients with relatively stable conditions, the routine monitoring of their core vital signs (heart rate, respiration, and body temperature) mainly relies on the responsible nurse using portable measuring devices to perform manual bedside measurements and records at regular intervals. Although some wards are equipped with bedside multi-parameter monitors, these are usually bulky, require a fixed connection to a mains power supply, and need to be connected to multiple independent electrode pads attached to the patient's chest via cables, restricting the patient's freedom of movement and getting out of bed. With the advancement of smart hospital construction, nurses are now using handheld mobile nursing PDAs for patient identification, medical order execution, and manual entry of vital signs. However, these devices themselves do not have the function of automatically collecting vital signs; the vital sign data they receive still relies on secondary input after manual measurement by the nurse.

[0003] First, because nurses typically take manual measurements at intervals of 2-4 hours or even longer, continuous 24-hour monitoring is impossible. This means that if a patient experiences a sudden drop in heart rate, respiratory arrest, or abnormal temperature fluctuations between two measurement points, nurses cannot immediately receive this information from the system, creating a significant blind spot in nursing observation. Second, even if the ward is equipped with traditional bedside monitors, the complex connection methods of multiple electrodes and cables not only increase skin irritation and discomfort for patients, but also make it easy for electrodes to fall off or cause signal interference when patients turn over or move, generating numerous false alarms and reducing nurses' sensitivity to real emergencies. Third, data collected by traditional bedside monitors is usually only displayed on the device's own screen in the ward or transmitted to the workstation at the central nursing station, and cannot be directly and point-to-point sent to the nurse's portable nursing PDA. When nurses leave the nursing station for rounds, if a patient suddenly experiences a zero heart rate or respiratory arrest, the nurse's PDA will not receive any alarm signal, resulting in a significant time delay between the occurrence of a crisis and the nurse's arrival at the bedside for resuscitation.

[0004] Therefore, to address the aforementioned issues of inability to achieve continuous monitoring and mobile alarm, this invention proposes an integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device at the apex of the heart. This device integrates a mechanical heart rate sensor, a mechanical respiratory fluctuation sensor, and a body temperature detection module within a flexible base to synchronously collect three core vital signs. It then uses a built-in wireless transmission module to send the data point-to-point in real time to a mobile nursing PDA carried by the nurse. When the heart rate drops to zero or breathing stops, both a local audible and visual alarm and a pop-up vibration alarm on the PDA are triggered simultaneously, thus filling the monitoring blind spots during nursing rounds and enabling immediate, on-the-go response to emergency signals. Summary of the Invention

[0005] In order to overcome the problems mentioned in the background art (which should be simplified), this invention proposes an integrated electrocardiogram, body temperature and respiratory mechanical sensing alarm device at the apex of the heart.

[0006] The technical solution of this invention is: an integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device at the apex of the heart, comprising: The flexible fitting base has a bottom shape that adapts to the physiological curvature of the apex of the heart at the intersection of the left clavicular midline and the fifth intercostal space. The back of the flexible fitting base is provided with a medical low-sensitivity adhesive layer, which is used to attach and fix the entire device to the skin of the patient's apex of the heart and deform synchronously with the patient's chest movement and heartbeat. The apex mechanical heart rate sensor is integrated in the central area of ​​the flexible, fitted base. This apex mechanical heart rate sensor is used to respond to the impact force generated by each mechanical beat of the heart to undergo compression and reset movements, triggering counting pulses through mechanical vibration and generating the raw heart rate signal. A mechanical respiratory wave sensing component for the thoracic cage is integrated into the outer peripheral area of ​​a flexible, fitted base. This mechanical respiratory wave sensing component for the thoracic cage includes a flexible strip extending along the direction of thoracic expansion. This flexible strip is used to perform linear expansion and contraction reciprocating motion in response to changes in the circumference of the thoracic cage during the patient's inhalation and exhalation, generating a raw signal of respiratory rate through mechanical displacement. An integrated body temperature detection and sensing module is integrated inside the flexible and fitting base and is in direct contact with the skin to collect the patient's apex body surface temperature signal in real time. The data processing and wireless transmission module is built into the flexible fitting base. This data processing and wireless transmission module is electrically connected to the apical mechanical heart rate sensor, the thoracic mechanical respiratory fluctuation sensor and the integrated body temperature detection sensor, respectively, and is used to convert the raw heart rate signal, the raw respiratory rate signal and the body surface temperature signal into real-time vital signs data. A local audible and visual alarm, electrically connected to a data processing and wireless transmission module, includes a buzzer and an LED warning light; The wireless transmission module is used to directly send real-time vital sign data to the pre-bound mobile nursing PDA terminal at the nurse station via a wireless communication protocol. It also has internally preset heart rate zeroing thresholds and respiratory arrest thresholds. When the heart rate value in the real-time vital sign data is determined to be lower than the heart rate zeroing threshold or the respiratory rate value is lower than the respiratory arrest threshold, the data processing and wireless transmission modules simultaneously execute a first control and a second control: the first control is to drive the local audible and visual alarm to issue an audible and visual alarm; the second control is to send an emergency alarm command to the mobile nursing PDA terminal at the nurse station, thereby triggering the PDA terminal to execute pop-up windows, red text display, and vibration alerts.

[0007] Preferably, the bottom of the flexible fitting base is made of a medical-grade soft silicone and non-woven fabric composite material, and its overall outline is an elliptical or circular shape adapted to the anatomical structure of the apex of the heart. The medical low-sensitivity adhesive layer is an acrylic medical pressure-sensitive adhesive layer, whose adhesive strength can support continuous wear of the device for more than 72 hours without causing skin allergic reactions. The integrated body temperature detection sensing module is a patch-type negative temperature coefficient thermistor sensor, whose temperature sensing surface protrudes 0.1mm to 0.5mm from the inner surface of the flexible fitting base and is arranged adjacent to the mechanical heart rate sensor component at the apex of the heart. The body temperature measurement accuracy of the thermistor sensor is ±0.1℃. The data wireless transmission module adopts a low-power Bluetooth 5.0 or RFID wireless transmission protocol. It internally stores a unique device ID and the corresponding patient identification code. When the device is used for the first time, it is paired and bound with the nurse station mobile nursing PDA terminal by scanning the code to achieve one-to-one exclusive data transmission. The data transmission frequency is once per second.

[0008] Preferably, the apical mechanical heart rate sensing component includes a central top rod, an elastic reset member surrounding the central top rod, and a mechanical micro switch located on top of the elastic reset member. One end of the elastic reset member is fixed to the flexible fitting base, and the other end is fixed to the central top rod. The heartbeat is transmitted through the skin to the central push rod, which drives the central push rod to overcome the elastic force of the elastic reset element and press the mechanical micro switch. Each press generates a counting pulse, and the frequency of the counting pulse corresponds to the heart rate. The measurable range of this heart rate sensing component is 0 beats / min to 200 beats / min. The thoracic mechanical respiratory fluctuation sensing component includes a fixed guide sleeve embedded in a flexible fitting base, a sliding rod slidably connected within the fixed guide sleeve, a flexible strip fixed to the sliding rod, a baffle plate fixed to the fixed guide sleeve, a spring fixed between the sliding rod and the baffle plate, a Hall linear sensor embedded in the fixed guide sleeve, and a permanent magnet embedded in the sliding rod. The free end of the flexible strip is provided with a second medical low-sensitivity adhesive layer, which is adhered to the surface of the thoracic skin. When the thoracic cavity expands, it pulls the sliding rod out relative to the fixed guide sleeve, causing the relative distance between the permanent magnet and the Hall linear sensor to change continuously. This results in a linear change in the magnetic induction intensity at the location of the Hall element; the stronger the magnetic induction intensity, the higher the Hall voltage; the weaker the magnetic induction intensity, the lower the Hall voltage. When the thoracic cavity contracts, the spring pushes the sliding rod back to its original position. The respiratory rate can be obtained by measuring the number of voltage waveform cycles per unit time.

[0009] Preferably, the data processing and wireless transmission module further includes a data caching unit for storing real-time vital sign data from the past 15 minutes. This caching unit automatically saves the data when the wireless connection is interrupted and automatically resumes transmission to the nurse station mobile nursing PDA terminal once the connection is restored. Data transmission resumes using a breakpoint resumption mechanism. The device also includes a miniature button battery compartment electrically connected to the data processing and wireless transmission module, the apical mechanical heart rate sensor, the chest mechanical respiratory fluctuation sensor, the integrated body temperature detection sensor module, and the local audible and visual alarm. This compartment powers the entire device. The data processing and wireless transmission module also has a built-in low-battery detection unit. When the battery level is below 10% of the total battery capacity or the voltage is below 2.8V, a low-battery replacement reminder is sent to the nurse station mobile nursing PDA terminal via the wireless transmission module every 5 minutes until the battery is replaced.

[0010] Preferably, the buzzer of the local audible and visual alarm has an emergency stop button function. The emergency stop button is integrated into the edge of the flexible base. When the buzzer sounds, pressing and holding the emergency stop button for more than 3 seconds can manually turn off the local audible and visual alarm, but will not interrupt the sending of alarm commands to the mobile nursing PDA terminal at the nurse station until the nurse confirms the processing on the PDA. The emergency alarm command sent to the mobile nursing PDA terminal at the nurse station includes the following fields: patient bed number, patient name, alarm type (heart rate zero or respiratory arrest), real-time heart rate value, real-time respiratory rate value, and the exact timestamp of the alarm occurrence. Upon receiving the alarm command, the PDA terminal will forcibly pop up a floating window and vibrate continuously until the nurse manually clicks to confirm. If the alarm command is not confirmed within 30 seconds, the PDA terminal will automatically forward the alarm command to other nurses' PDAs in the same responsibility group.

[0011] Preferably, the heart rate zeroing threshold is defined as the absence of any counting pulses detected within three consecutive heart rate detection cycles, which is considered a zero heart rate; the respiratory arrest threshold is defined as the absence of any respiratory fluctuation or displacement signal detected within 20 consecutive seconds, which is considered a respiratory arrest. When both the heart rate zeroing and respiratory arrest conditions are met simultaneously, the buzzer of the local audible and visual alarm outputs an intermittent, rapid buzzing sound of at least 85 decibels, and the LED warning light flashes red light at a frequency of 3 times per second, which is different from the alarm mode when a single physiological parameter is abnormal (a single alarm for low heart rate flashes once per second, and a single alarm for bradykinesia flashes twice per second), thus achieving graded indication of the severity of the emergency.

[0012] The beneficial effects of this invention are: 1. This invention achieves continuous, stable, and non-invasive synchronous mechanical sensing of the strongest signal points of heartbeat and chest wall movement by using a flexible, fitted base specifically adapted to the physiological curvature of the left midclavicular line and the apex of the fifth rib, and integrating a purely mechanical heart rate sensing component and a mechanical respiratory fluctuation sensing component. This solves the problem that traditional manual timed measurements cannot achieve 24-hour continuous monitoring and fills the blind spot of vital signs during nursing rounds.

[0013] 2. This invention uses a micro-mechanical pressure sensing spring and a flexible mechanical telescopic sensing strip to sense heart rate and respiration in a purely mechanical structure. It does not rely on electrophysiological electrodes or photoelectric sensors at all, avoiding skin irritation, easy detachment, and motion artifact interference caused by multiple electrode pads and cable connections in traditional monitors. This significantly reduces the false alarm rate. At the same time, a single apical patch integrates the collection of three vital signs, reducing the foreign body sensation on the patient's body surface. It is comfortable to wear and does not affect turning over.

[0014] 3. The invention has a built-in wireless transmission module that sends data directly point-to-point to the mobile nursing PDA terminal carried by the nurse. It also has a dual mechanism of local sound and light alarm and PDA pop-up vibration alarm. When the heart rate drops to zero or breathing stops, the nurse can receive the emergency alarm immediately without relying on the central workstation or bedside monitor screen. This solves the problem that traditional monitoring data cannot follow the nurse's movement, shortens the rescue response time to the second level, and greatly improves the safety level of ward nursing. Attached Figure Description

[0015] Figure 1 The diagram shown is a schematic representation of the overall three-dimensional structure of the present invention; Figure 2 The diagram shown is an internal schematic of the present invention; Figure 3 The diagram shown is a schematic representation of the thoracic mechanical respiratory fluctuation sensing component of the present invention. Figure 4 The diagram shown is a cross-sectional view of the device of the present invention. Figure 5 The diagram shown is a bottom-view cross-sectional view of the present invention.

[0016] Explanation of reference numerals in the attached diagram: 1. Flexible fitting base; 2. Apical mechanical heart rate sensor assembly; 201. Central top rod; 202. Elastic reset component; 203. Mechanical micro switch; 3. Chest mechanical respiratory rise and fall sensor assembly; 301. Fixed guide sleeve; 302. Sliding rod; 303. Flexible strip; 304. Block plate; 305. Spring; 306. Hall linear sensor; 307. Permanent magnet; 4. Integrated body temperature detection sensor module; 5. Buzzer; 6. LED warning light; 7. Medical low-sensitivity adhesive layer one; 8. Medical low-sensitivity adhesive layer two; 9. Miniature button battery compartment. Detailed Implementation

[0017] 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 some embodiments of the present invention, but 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.

[0018] Please see Figures 1-5 The present invention provides an embodiment: This device includes a flexible, conformal base, a mechanical heart rate sensor at the apex of the heart, a mechanical respiratory fluctuation sensor at the chest, an integrated body temperature detection module, a data processing and wireless transmission module, a local audible and visual alarm, and a miniature button battery compartment. The flexible, conformal base serves as the substrate and carrier of the entire device. Its bottom shape has been optimized using extensive 3D surface scan data of the human apex of the heart, specifically adapting to the physiological curvature of the apex at the intersection of the left midclavicular line and the fifth intercostal space (this location has the strongest heartbeat, the most pronounced chest fluctuations, and a relatively stable surface temperature, making it the golden point for collecting three vital signs). The base is made of a medical-grade soft silicone and non-woven fabric composite material laminated and hot-pressed. The soft silicone layer provides sufficient flexibility and resilience, allowing the base to deform synchronously with the patient's breathing and heartbeat without irreversible plastic deformation; the non-woven fabric layer provides the base with a certain tensile strength, preventing breakage during application and removal. The back of the base (the side that comes into contact with the skin) is evenly coated with an acrylic medical pressure-sensitive adhesive layer. This adhesive layer has undergone biocompatibility testing and will not cause skin redness, itching or allergic reactions after being worn continuously for more than 72 hours. At the same time, its adhesiveness is sufficient to resist the shearing force generated by the patient's daily movements such as turning over, sitting up, and walking, ensuring that the device will not shift or fall off within the predetermined service life.

[0019] A circular recessed mounting position is provided in the center of the flexible, form-fitting base to accommodate the apical mechanical heart rate sensor. When this mounting position is aligned with the apex of the heart, the pressure-sensitive adhesive layer on the back of the base, after contact with the skin, directly transmits the minute pulsating impact force from the skin surface to the sensor. A telescopic structure for the thoracic mechanical respiratory fluctuation sensor is installed on the outer periphery of the base. The integrated body temperature detection module is located on the inner surface of the base, adjacent to the heart rate sensor, ensuring continuous, pressure-free thermal contact with the skin. The data processing and wireless transmission module is encapsulated in a sealed cavity in the center of the base within a miniature button battery compartment. This cavity is waterproofed and dustproof using a silicone potting process, achieving an IPX4 protection rating, and can withstand the perspiration of patients during daily activities. The buzzer and LED warning light of the local audible and visual alarm are installed on the front edge of the base in an easily visible and audible location.

[0020] Please see Figure 2 and Figure 4 In this embodiment, the apical mechanical heart rate sensor component is described in detail: The apex mechanical heart rate sensor uses a purely mechanical structure to sense heartbeats. This component includes a central push rod, a resilient reset element surrounding the central push rod, and a mechanical microswitch located at the bottom of the resilient reset element. These three sub-components are coaxially nested within a metal housing. The central push rod is embedded in the adhesive backing of the base to ensure that it can directly contact the cardiac shockwave transmitted from the skin surface.

[0021] In use, after the nurse attaches the device to the skin at the apex of the heart, located at the intersection of the left midclavicular line and the fifth intercostal space, the free end of the central push rod rests against the skin at that point. With each contraction and relaxation of the heart, the apex experiences an outward (towards the body surface) mechanical impact, with an amplitude of approximately 0.5-2 mm in a healthy adult. This mechanical impact force is transmitted through the subcutaneous tissue to the skin surface, acting on the central push rod and driving it to overcome the elastic force of the resilient repositioning element and move inwards into the device. The resilient repositioning element is a miniature helical spring with an elastic coefficient ranging from 0.1 to 0.3 Newtons per millimeter.

[0022] The mechanical microswitch is located at the bottom of the elastic reset component. After moving a certain distance, the tail end of the central push rod strikes the trigger electrode of the microswitch, causing the two contacts inside the switch to conduct instantaneously, thereby generating an electrical pulse signal with a width of approximately several milliseconds. Each heartbeat generates one pulse, and the frequency of the pulse directly corresponds to the heart rate. Unlike conventional ECG monitoring equipment, which requires complex signal processing such as analog-to-digital conversion and QRS wave recognition, the pulse signal generated by this device is a digital, raw counting pulse that requires no additional processing. The data processing and wireless transmission modules only need to count the number of pulses per unit time to obtain the real-time heart rate value. This purely mechanical induction method has extremely strong anti-interference capabilities. Slight tremors of the patient's body, vibrations of the hospital bed, and electromagnetic interference sources (such as mobile phones and electric hospital bed motors) cannot trigger the mechanical microswitch, because only a mechanical impact with a certain impact energy (approximately equal to the kinetic energy generated by a heartbeat) can push the central push rod past the trigger threshold of the microswitch.

[0023] To ensure continuous and stable contact between the sensor and the skin, the pressure-sensitive adhesive layer of the flexible base features a locally thickened design around the heart rate sensing component. This causes the skin at the apex of the heart to slightly bulge upwards after the base is attached, forming a small mound that gently lifts the central push rod by approximately 0.3 mm of pre-pressure. This pre-pressure ensures that even if the patient takes a deep breath or slightly changes position, the central push rod will not lose contact with the skin, thus preventing missed heart rate readings.

[0024] Please see Figure 2 and Figure 3 In this embodiment, the mechanical respiratory rise and fall sensing component of the thoracic cavity is described in detail: The mechanical respiratory fluctuation sensor component is responsible for synchronously acquiring the patient's respiratory rate signal. Since the apex of the heart is located in the lower left thoracic region, the skin in this area undergoes significant linear displacement changes with the expansion and contraction of the thoracic cavity. During inspiration, the diaphragm descends, the intercostal spaces widen, and the skin at the apex moves outward and downward in a direction roughly perpendicular to the anterior midline; during expiration, the skin retracts inward and upward. This device utilizes this physiological characteristic, employing a flexible strip to convert the circumferential changes of the thoracic cavity into countable reciprocating motion cycles.

[0025] The components include a fixed guide sleeve embedded in a flexible fitting base, a sliding rod slidably connected within the fixed guide sleeve, a flexible strip fixed to the sliding rod, a baffle plate fixed to the fixed guide sleeve, a spring fixed between the sliding rod and the baffle plate, a Hall linear sensor embedded in the fixed guide sleeve, and a permanent magnet embedded in the sliding rod. The free end of the flexible strip is provided with a second medical low-sensitivity adhesive layer, which is adhered to the surface of the chest skin. When the chest expands, it pulls the sliding rod out relative to the fixed guide sleeve, causing the relative distance between the permanent magnet and the Hall linear sensor to change continuously. This results in a linear change in the magnetic induction intensity at the location of the Hall element; the stronger the magnetic induction intensity, the higher the Hall voltage; the weaker the magnetic induction intensity, the lower the Hall voltage. When the chest contracts, the spring pushes the sliding rod back to its original position. The respiratory rate can be obtained by measuring the number of voltage waveform cycles per unit time.

[0026] When a patient breathes, the expansion and contraction of the chest cavity causes the sliding rod to reciprocate linearly relative to the fixed guide sleeve. When the sliding rod extends, the permanent magnet fixed at its tail end moves away from the Hall sensor; when the sliding rod retracts, the permanent magnet moves closer to the Hall element. The constantly changing relative distance between the permanent magnet and the Hall element causes a linear change in the magnetic induction intensity at the location of the Hall element.

[0027] According to the Hall effect principle, when a Hall sensor is subjected to a constant excitation current, a Hall voltage is generated in the direction perpendicular to both the current and the magnetic field. The magnitude of this Hall voltage is directly proportional to the magnetic flux density; the stronger the magnetic flux density, the higher the Hall voltage; and the weaker the magnetic flux density, the lower the Hall voltage. Since the magnetic flux density is approximately linearly related to the distance between the permanent magnet and the Hall element, the Hall voltage is also approximately linearly related to the displacement of the sliding rod.

[0028] The microcontroller in the data processing and wireless transmission module reads the voltage value output by the Hall linear sensor at a sampling rate of 20 times per second via an analog-to-digital converter. As the patient alternates between inhalation and exhalation, the Hall voltage exhibits a periodic rising and falling waveform: during inhalation, the chest expands, the sliding rod extends, the permanent magnet moves away from the Hall element, the magnetic induction intensity weakens, and the Hall voltage decreases; during exhalation, the chest contracts, the sliding rod retracts, the permanent magnet moves closer to the Hall element, the magnetic induction intensity strengthens, and the Hall voltage rises. After digitally low-pass filtering the acquired voltage waveform, the microcontroller identifies the peak and trough values. Each complete inhalation-exhalation cycle (from the trough to the peak and then to the next trough, or from the peak to the trough and then to the next peak) corresponds to one respiratory movement. The respiratory rate can be obtained by counting the number of cycles per unit time.

[0029] When the patient's breathing stops, the sliding rod remains stationary at a certain position, and the Hall voltage remains essentially constant (with only slight circuit noise fluctuations). The microcontroller determines that breathing has stopped when it detects that the maximum change in the voltage waveform within 20 consecutive seconds is less than the voltage change corresponding to 0.3 mm, triggering the alarm logic.

[0030] Compared to sliding rheostats, this Hall effect-based linear displacement detection method offers advantages such as non-contact, frictionless operation, long lifespan, and fast response, making it particularly suitable for respiratory monitoring scenarios requiring long-term reciprocating motion. Since there is no mechanical contact between the permanent magnet and the Hall element, the risk of signal drift or failure due to sliding wear is completely eliminated, further improving the long-term reliability of the device. Furthermore, the Hall linear sensor outputs an analog voltage, and its resolution depends solely on the number of bits in the analog-to-digital converter. In practical applications, a displacement resolution better than 0.2 mm can be easily achieved, sufficient to precisely capture the subtle chest wall movements during shallow, slow breathing, making it especially beneficial for respiratory monitoring in elderly patients with chronic diseases or those weakened after surgery.

[0031] In this embodiment, the mechanical respiratory rise and fall sensing component of the thoracic cavity is described in detail: The integrated body temperature detection and sensing module is responsible for real-time acquisition of the patient's apex body surface temperature. The apex was chosen as the temperature acquisition point because this area has a rich blood supply, thin subcutaneous tissue, and is far from the extremities, resulting in good correlation between its surface temperature and core body temperature (such as rectal and esophageal temperatures), with a time delay typically not exceeding 2 minutes. This module uses a patch-type negative temperature coefficient thermistor sensor, with its sensing surface protruding 0.1-0.5 mm from the inner surface of the flexible, fitted base, ensuring close thermal contact between the sensor and the skin. The sensor and the miniature mechanical pressure sensing spring are positioned adjacent to each other, with a distance between them controlled within 5 mm. This allows them to share the stable thermal environment of the apex without interfering with each other's mechanical sensing.

[0032] A negative temperature coefficient thermistor is a semiconductor ceramic element whose resistance decreases as temperature increases. In this device, the thermistor, along with a precision voltage divider circuit and analog-to-digital converter within the data processing and wireless transmission module, forms the body temperature measurement path. The data processing module reads the voltage across the thermistor once per second and converts the voltage into a temperature value using a built-in calibration curve. Because the thermistor's resistance-temperature characteristic is non-linear, each sensor undergoes three-point calibration (35℃, 37℃, 39℃) before leaving the factory. The calibration coefficients are stored in the read-only memory of the data processing module, ensuring a body temperature measurement accuracy of ±0.1℃ within the clinical measurement range of 30℃ to 43℃.

[0033] In this embodiment, the data processing and wireless transmission module will be described in detail: The data processing and wireless transmission module receives raw electrical signals from the heart rate sensor, respiration sensor, and body temperature detection module, converts these signals into standardized real-time vital signs data, and transmits the data to the nurse's portable nursing PDA terminal via a wireless communication protocol. This module is built into a sealed cavity within a flexible, fitted base and mainly includes a miniature low-power microcontroller, a data buffer unit, and a wireless radio frequency transceiver unit.

[0034] The miniature low-power microcontroller uses a Cortex-M0 core or equivalent, operating at only around 32MHz. Its standby current is less than 1 microamp, and its average operating current does not exceed 3 milliamps, ensuring continuous operation for over 72 hours on a single CR2032 coin cell battery. The microcontroller internally integrates the device's core algorithm logic, including pulse counting, respiratory cycle detection, temperature analog-to-digital conversion, and alarm threshold comparison.

[0035] In terms of heart rate signal processing, the microcontroller monitors the output pulses of the mechanical microswitch via a dedicated timer / counter pin. Because the pulse width generated by each heartbeat is extremely narrow (approximately 1-5 milliseconds), the microcontroller uses an interrupt method to record the arrival time of each pulse and calculates the time interval between two consecutive pulses (i.e., the RR interval). Unlike simply counting the number of pulses per minute, this device also has heart rate variability analysis capabilities. By calculating the standard deviation of five consecutive heartbeat intervals, it can preliminarily assess the patient's autonomic nervous system function. However, as the core function of the alarm device, the heart rate value is generated using a sliding window averaging method, updating the current heart rate value every 3 seconds (the calculation formula is: the total number of pulses in the past 30 seconds divided by 0.5 minutes). When no counting pulses are detected within three consecutive heartbeat detection cycles, the microcontroller determines that the heart rate has reached zero and immediately triggers the alarm logic.

[0036] Similarly, respiratory signal processing involves a microcontroller that reads the output voltage of the linear displacement sensor at a sampling rate of 20 times per second via an analog-to-digital converter. After passing through a digital low-pass filter (cutoff frequency 2Hz), the peak and trough values ​​of the displacement waveform are identified. Each time a complete inspiratory-expiratory cycle (i.e., from trough to peak and then to the next trough) is detected, the respiratory cycle counter increments by 1. If no valid cycle is detected for 20 seconds (the amplitude change between adjacent peaks is less than 0.3mm), respiratory arrest is determined.

[0037] The body temperature signal is sampled once per second, and the median value of 5 consecutive samples is taken as the current displayed temperature to eliminate burr noise caused by momentary poor contact or external thermal interference.

[0038] The data buffer unit is large enough to store all vital sign historical data from the past 15 minutes, including heart rate, respiratory rate, and temperature every 10 seconds. The storage format is a simple binary format, with each record timestamped. When the wireless connection is interrupted due to distance, signal obstruction, or PDA terminal sleep mode, the microcontroller automatically writes real-time data to the buffer circular queue. Once the connection is restored, the interrupted data is resent to the PDA terminal in chronological order via a breakpoint resume mechanism, ensuring no frames are lost in the nursing records.

[0039] The wireless RF transceiver unit adopts either Bluetooth Low Energy 5.0 or RFID wireless transmission protocols. Bluetooth Low Energy 5.0 has the advantages of long transmission distance (up to 30 meters in open environments) and good compatibility with existing smart terminals; while RFID (especially near-field communication mode) can achieve short-range data transmission with extremely low power consumption.

[0040] In this embodiment, the local audible and visual alarm will be described in detail: The local sound and light alarm and the remote alarm on the PDA constitute the dual safety protection mechanism of this device. When a patient experiences an extreme emergency such as a zero heart rate or respiratory arrest, it can alert the bedside staff or the circulating nurse in the shortest possible time with the strongest perception, achieving a response within seconds.

[0041] Local audible and visual alarms include a buzzer and LED warning lights.

[0042] When the microcontroller confirms that the heart rate has reached zero or breathing has stopped according to the aforementioned judgment logic, it immediately activates the alarm. This device also features a tiered alarm mode to differentiate between single parameter abnormalities and simultaneous zeroing of two parameters. Specifically: if only the heart rate is below the bradycardia threshold (below 40 beats / min but not zero) or only the respiratory rate is below the bradycardia threshold (below 8 breaths / min but not stopped), a normal alarm is triggered, with the buzzer sounding once per second and the LED flashing once per second (red); if the heart rate is zero but breathing is still present, or breathing has stopped but the heart rate is still present, a severe alarm is triggered, with the buzzer sounding twice per second and the LED flashing twice per second (red); if both the heart rate and breathing have stopped simultaneously, the most critical alarm is triggered, with the buzzer emitting a rapid beeping sound three times per second and the LED flashing three times per second, while the buzzer pitch increases to approximately 4.5kHz for the strongest warning effect.

[0043] After the local audible and visual alarm is activated, nurses or caregivers can manually disable it by pressing and holding the emergency stop button integrated into the edge of the flexible base for more than 3 seconds. Manually disabling the local alarm will not interrupt the transmission of alarm commands to the mobile nursing PDA terminal at the nursing station. This is to prevent the alarm signal from being completely suppressed due to accidental activation or unauthorized disabling by nurses. The entire alarm process is only officially deactivated after the responsible nurse or on-duty nurse logs into the dedicated application on the PDA terminal and clicks the "Confirm Processed" button. Before the PDA confirms the processing, even if the local buzzer is turned off, the device will still send an alarm command to the PDA every 30 seconds.

[0044] The alarm command from the PDA includes the following required fields: patient bed number, patient name, alarm type, real-time heart rate (integer, beats / min), real-time respiratory rate (integer, beats / min), and the exact timestamp of the alarm occurrence. Upon receiving this command, the PDA will force a pop-up window regardless of the currently displayed application interface. The window background is bright red, and the text is bold white, displaying a warning message such as "'Emergency' Patient in bed XX has stopped breathing / heart rate has stopped. Immediate resuscitation is required!" in the largest font size. Simultaneously, the PDA activates the system's vibration motor to continuously vibrate in a long, sustained vibration pattern until the nurse touches the "Confirm" button on the screen.

[0045] The specific steps for using it are as follows: (1) The responsible nurse opens the dedicated vital signs monitoring application on the mobile nursing PDA terminal and selects the "New Patient Binding" function. Then, the nurse scans the QR code on the patient's wristband (to obtain the patient's name, bed number, hospital number, diagnosis, etc.) and the QR code on the outer packaging of the device (to obtain the device's unique ID). The application automatically binds the two and displays the patient's vital signs monitoring card on the PDA's main interface. The card initially displays "Waiting for Data".

[0046] (2) The nurse checks the position of the apex of the heart on the patient’s left midclavicular line and the fifth intercostal space, cleans the skin with a 75% alcohol swab, waits for the skin to dry, peels off the release paper on the back of the device, aligns the center of the flexible base with the apex of the heartbeat, attaches it smoothly, and at the same time gently smooths the free ends of the two flexible mechanical telescopic sensing strips on the periphery along the natural curvature of the chest towards the anterior axillary line to ensure that they are firmly attached and do not fold.

[0047] (3) Observe whether the vital signs data have started to update on the PDA terminal. Under normal circumstances, the real-time values ​​of heart rate, respiratory rate and body temperature will be displayed on the PDA within 5 seconds after pasting. The nurse can ask the patient to take a deep breath and observe whether the respiratory rate value fluctuates synchronously to verify that the sensor is working properly.

[0048] (4) During the subsequent continuous monitoring, nurses no longer need to carry thermometers, stethoscopes, or finger-clip pulse oximeters to the patient's bedside for manual measurement. They can simply glance at the monitoring card list on the PDA during breaks to obtain all the vital signs of the patients they have linked. If any abnormality occurs (such as rapid heart rate, slow breathing, or elevated body temperature), the PDA will alert the nurse with a non-emergency pop-up (yellow background); only when the heart rate drops to zero or breathing stops will the aforementioned red emergency pop-up and vibration be triggered.

[0049] (5) When an alarm occurs, the nurse shall immediately rush to the corresponding bedside to provide emergency care. After confirming the patient's condition at the bedside, the nurse shall first turn off the local buzzer by pressing and holding the emergency stop button on the device, and then click "Confirm Processing" on the PDA. The system shall automatically record the time interval from alarm triggering to confirmation, which shall be used as one of the nursing quality assessment indicators.

[0050] (6) When the PDA receives a low battery warning, the nurse can go to the patient's bedside at a convenient time to open the battery compartment cover and replace it with a new button battery. The device will automatically resume operation without needing to be re-tied. If the patient is discharged or no longer needs continuous monitoring, the nurse can simply tear off the entire device and dispose of it as medical waste.

[0051] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device at the apex of the heart, characterized in that: include: The flexible fitting base (1) has a bottom shape that is adapted to the physiological curvature of the apex of the heart at the intersection of the left clavicle midline and the fifth intercostal space. The back of the flexible fitting base (1) is provided with a medical low-sensitivity adhesive layer, which is used to attach and fix the entire device to the skin of the patient's apex and deform synchronously with the patient's chest movement and heartbeat. A mechanical heart rate sensor (2) is integrated in the central area of ​​a flexible fitting base (1). The mechanical heart rate sensor (2) is used to respond to the impact force generated by each mechanical heartbeat and to perform compression and reset movements. It triggers counting pulses through mechanical vibration and generates the original heart rate signal. The mechanical respiratory fluctuation sensing component (3) is integrated in the outer peripheral area of ​​the flexible fitting base (1). The mechanical respiratory fluctuation sensing component (3) includes a flexible strip (303) extending along the direction of chest expansion. The flexible strip (303) is used to perform linear expansion and reciprocating motion in response to changes in chest circumference during the patient's inhalation and exhalation, and generates the original signal of respiratory frequency through mechanical displacement. An integrated body temperature detection and sensing module (4) is integrated inside the flexible fitting base (1) and in direct contact with the skin, used to collect the patient's apex body surface temperature signal in real time; The data processing and wireless transmission module is built into the flexible fitting base (1). The data processing and wireless transmission module is electrically connected to the apical mechanical heart rate pulsation sensing component (2), the thoracic mechanical respiratory fluctuation sensing component (3), and the integrated body temperature detection sensing module (4) respectively, and is used to convert the raw heart rate signal, the raw respiratory rate signal and the body surface temperature signal into real-time vital signs data. A local audible and visual alarm is electrically connected to a data processing and wireless transmission module (5). The local audible and visual alarm includes a buzzer (5) and an LED warning light (6). The data processing and wireless transmission module is used to send an emergency alarm command to the mobile nursing PDA terminal at the nurse station and also to drive the buzzer (5) and LED warning light (6) to sound an alarm.

2. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The bottom of the flexible adhesive base (1) is made of medical-grade soft silicone and non-woven fabric composite material. Its overall outline is an elliptical or circular shape that adapts to the anatomical structure of the apex of the heart. The medical low-sensitivity adhesive layer is an acrylic medical pressure-sensitive adhesive layer.

3. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The apical mechanical heart rate sensing component (2) includes a central top rod (201), an elastic reset member (202) surrounding the central top rod (201), and a mechanical micro switch (203) located on top of the elastic reset member (202). One end of the elastic reset member (202) is fixed to the flexible fitting base (1), and the other end is fixed to the central top rod (201). The heartbeat is transmitted through the skin to the central push rod (201), which drives the central push rod (201) to overcome the elastic force of the elastic reset element (202) and press the mechanical micro switch (203). Each press generates a counting pulse, and the frequency of the counting pulse corresponds to the heart rate.

4. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The thoracic mechanical respiratory fluctuation sensing component (3) includes a fixed guide sleeve (301) embedded in a flexible fitting base (1), a sliding rod (302) slidably connected in the fixed guide sleeve (301), a flexible strip (303) fixed to the sliding rod (302), a baffle plate (304) fixed to the fixed guide sleeve (301), a spring (305) fixed between the sliding rod (302) and the baffle plate (304), a Hall linear sensor (306) embedded in the fixed guide sleeve (301), and a permanent magnet (307) embedded in the sliding rod (302); the flexible strip (306) is further defined as follows: 3) The free end is provided with a medical low-sensitivity adhesive layer 2 (8), which is attached to the surface of the chest skin. When the chest expands, the sliding rod (302) is pulled out relative to the fixed guide sleeve (301). The relative distance between the permanent magnet (307) and the Hall linear sensor (306) changes continuously, causing the magnetic induction intensity at the location of the Hall element to change linearly. The stronger the magnetic induction intensity, the higher the Hall voltage; the weaker the magnetic induction intensity, the lower the Hall voltage. When the chest contracts, the spring (305) pushes the sliding rod (302) to reset. The respiratory rate can be obtained by measuring the number of voltage waveform cycles per unit time.

5. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The integrated body temperature detection sensing module (4) is a patch-type negative temperature coefficient thermistor sensor. Its temperature sensing surface protrudes 0.1-0.5mm from the inner surface of the flexible adhesive base (1) and is arranged adjacent to the apical mechanical heart rate sensing component (2).

6. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The wireless data transmission module stores a unique device ID and the corresponding patient's identification code. When the device is used for the first time, it is paired and bound to the nurse station's mobile nursing PDA terminal by scanning the code, so as to realize one-to-one exclusive data transmission.

7. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The data processing and wireless transmission module also includes a data caching unit, which stores real-time vital signs data from the past 15 minutes and automatically saves the data when the wireless connection is interrupted, and automatically resumes transmission to the mobile nursing PDA terminal at the nurse station after the connection is restored.

8. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The buzzer (5) of the local sound and light alarm has an emergency stop button function. The emergency stop button is integrated into the edge of the flexible base (1). When the buzzer (5) sounds, pressing the emergency stop button for more than 3 seconds can manually turn off the local sound and light alarm, but will not interrupt the sending of alarm instructions to the mobile nursing PDA terminal at the nurse station until the nurse confirms the processing on the PDA.

9. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The emergency alarm command sent to the mobile nursing PDA terminal at the nurse station includes the following fields: patient bed number, patient name, alarm type, real-time heart rate value, real-time respiratory rate value, and the exact timestamp of the alarm occurrence. Upon receiving the command, the mobile nursing PDA terminal at the nurse station will forcibly pop up a floating window and vibrate continuously until the nurse manually clicks to confirm.

10. The apical integrated electrocardiogram, body temperature, and respiratory mechanical sensing alarm device according to claim 1, characterized in that: The device also includes a miniature button battery compartment (9), which is electrically connected to the data processing and wireless transmission module, the apical mechanical heart rate sensor component (2), the thoracic mechanical respiratory fluctuation sensor component (3), the integrated body temperature detection sensor module (4), and the local audible and visual alarm to power the entire device. The data processing and wireless transmission module also has a built-in low battery detection unit. When the battery power is lower than a preset threshold, it sends a low battery replacement prompt to the mobile nursing PDA terminal at the nurse station through the wireless transmission module.

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