Liquid level alarm system for infusion bag

Abstract

The invention discloses an infusion bag liquid level alarm system, a sensor group is composed of a pressure sensor array, a photoelectric sensor module and a temperature compensation module, the pressure sensor array is installed at a bearing node of an infusion bag hanging support, and the photoelectric sensor module is vertically distributed along the side face of an infusion bag; the signal processing module is electrically connected with the sensor group, and the grading trigger logic triggers different alarm grades according to the liquid level drop rate and the residual amount; the power supply management module adopts a low-power-consumption design and supports seamless switching between battery power supply and an external power supply; pressure and a photoelectric sensor are complementary, limitation of a single sensor is overcome, precision is improved to + / -2mL, a self-adaptive threshold value is adopted, an alarm threshold value is dynamically adjusted, false alarm caused by infusion speed fluctuation is avoided, remote cooperative management is achieved, multi-bed centralized monitoring is achieved through a wireless network, the inspection frequency of medical staff is reduced, and the safety of medical staff is improved. The device is suitable for infusion bags (50mL-1000mL) of different specifications and various kinds of liquid medicine (transparent, semitransparent and opaque).

Description

Technical Field

[0001] The present invention relates to the technical field of medical equipment, and in particular to a real-time monitoring and alarm system for the liquid level of an infusion bag, which is particularly suitable for intelligent monitoring and early warning of the remaining amount of liquid in an infusion bag during clinical infusion. Background Art

[0002] In medical care, intravenous infusion is a common treatment method, but during the infusion process, medical staff need to frequently observe the liquid level in the infusion bag to avoid the risk of air entering the blood vessels or blood reflux due to failure to handle the liquid infusion in time. The traditional manual monitoring method has the following defects:

[0003] Low efficiency: Relying on manual observation, medical staff have a heavy workload and are prone to missed detections due to fatigue or negligence.

[0004] Poor accuracy: When the liquid level approaches the end point, it is difficult to accurately judge the remaining time by naked eyes.

[0005] No early warning function: Medical staff cannot be notified in advance to change the infusion bag, especially at night or during peak hours, when the risk is higher.

[0006] In the prior art, some liquid level detection devices use a single sensor (such as a gravity sensor or an optical sensor), but they have the following disadvantages:

[0007] The material of the infusion bag, the transparency of the liquid or the ambient light may interfere with the detection, resulting in false alarms or missed alarms.

[0008] Unable to dynamically adapt to different infusion bag specifications or liquid viscosity differences.

[0009] There is a lack of a multi-level alarm mechanism, and it is impossible to distinguish the degree of urgency.

[0010] Therefore, there is an urgent need for an infusion bag liquid level alarm system with high precision, strong anti-interference ability and intelligent early warning function. Summary of the invention

[0011] In order to overcome the deficiencies of the prior art, one of the purposes of the present invention is to provide an infusion bag liquid level alarm system.

[0012] One of the purposes of the present invention is achieved by adopting the following technical solution: an infusion bag liquid level alarm system, comprising:

[0013] Sensor group: It consists of a pressure sensor array, a photoelectric sensor module, and a temperature compensation module. The pressure sensor array is installed at the load-bearing node of the infusion bag suspension bracket, and the photoelectric sensor module is vertically distributed along the side of the infusion bag;

[0014] Signal processing module: electrically connected to the sensor group, used for filtering, fusing and dynamic threshold calculation of multi-source sensor data;

[0015] Alarm module: including an audible and visual alarm unit, a wireless communication unit and a hierarchical trigger logic, wherein the hierarchical trigger logic triggers different alarm levels according to the liquid level drop rate and the remaining amount;

[0016] Power management module: adopts low power consumption design, supports seamless switching between battery power supply and external power supply;

[0017] User interaction interface: includes touch screen or physical buttons for parameter setting, alarm threshold adjustment and system status display.

[0018] Furthermore, the pressure sensor array is composed of at least 4 piezoresistive sensors, which are arranged in a rectangular array at four force-bearing points of the suspension bracket. After the output signal of each sensor is normalized, the real-time liquid weight is calculated by the following formula: Where W is the estimated value of liquid weight, Wi is the original reading of the i-th sensor, and Ki is the calibration coefficient of the corresponding position.

[0019] Furthermore, the calibration coefficient Ki of the pressure sensor array is determined by: recording the baseline value Wi0 of each sensor in an unloaded state; loading a standard weight to obtain the full scale value Wi1 of each sensor; calculating And normalized.

[0020] Furthermore, the photoelectric sensor module includes: at least 8 pairs of infrared transmitting tubes and receiving tubes, which are evenly distributed along the height direction of the infusion bag, with adjacent spacing of 5-15mm; a wavelength-adjustable light source, with an operating wavelength range of 850nm-1050nm, and the driving current is adjusted by PWM to switch the wavelength according to the color of the medicine solution; a light shield structure, covering the outside of the transmitting-receiving tube pair to reduce ambient light interference.

[0021] Furthermore, the liquid level determination logic of the photoelectric sensor module includes: when the light intensity attenuation rate of three or more consecutive receiving tubes exceeds a set threshold, the liquid level is determined to be in this interval; if the deviation between the pressure sensor and the photoelectric sensor liquid level data exceeds 5%, redundant verification is started, and the pressure sensor data is used preferentially.

[0022] Furthermore, the signal processing module performs the following operations:

[0023] The pressure sensor data is filtered using a sliding average filter with a window size of 0 to 500 sampling points;

[0024] Median filtering is used on the photoelectric sensor data to eliminate instantaneous interference;

[0025] The extended Kalman filter algorithm is used to fuse pressure and photoelectric data to output the estimated value of the liquid level. Its state equation is expressed as:

[0026] xk =x k-1 +Δt·υ k-1 +w k

[0027] z k =Hx k +v k

[0028] Furthermore, the dynamic threshold adjustment method includes:

[0029] In the initial stage, a fixed threshold is set according to the nominal capacity of the infusion bag;

[0030] Monitor the liquid level drop rate U within 30 seconds after the start of infusion. If U exceeds the preset range (0.5-5mL / min), it will automatically switch to the adaptive mode. In the adaptive mode, the quadratic curve is fitted with the historical liquid level data to predict the remaining infusion time T. When T <t safe (preset safety time) triggers the alarm.

[0031] Furthermore, the calculation formula of the safety time tsafe is:

[0032]

[0033] Among them, α is the safety factor (0.8-1.2), β is the redundancy time (1-3 minutes), V remaining is the current remaining fluid volume, and U is the average infusion rate in the last 10 minutes.

[0034] Furthermore, the hierarchical triggering logic of the alarm module includes:

[0035] Level 1 alarm: When the remaining liquid volume is less than 20% of the total capacity, a continuous low-frequency buzzer (frequency 1kHz, interval 2 seconds) and LED slow flashing (cycle 1 second) are triggered;

[0036] Second level alarm: When the remaining liquid volume is less than 5% or the predicted remaining time is less than 5 minutes, a high-frequency buzzer (frequency 3kHz, continuous sounding) and LED flash (cycle 0.3 seconds) are triggered, and an emergency alarm signal is sent to the nurse station and mobile terminal through the wireless communication module;

[0037] Fault alarm: When sensor data is abnormal or communication is interrupted for more than 30 seconds, the red LED will light up and the voice will broadcast "system fault".

[0038] Level 1 alarm: triggers a continuous low-frequency buzzer (frequency 1kHz, interval 2 seconds), and at the same time, a voice message "low liquid level, please pay attention" is broadcast every 5 seconds, and the LED keeps flashing slowly (cycle 1 second);

[0039] Secondary alarm: Switches to high-frequency beeping (frequency 3kHz, continuous beeping) and cyclically broadcasts the voice "Emergency: Insufficient remaining liquid, please deal with it immediately", and the LED turns to fast flashing (cycle 0.3 seconds);

[0040] Fault alarm: The red LED is always on, and the speaker repeats "System fault, please repair" every 10 seconds until the fault is rectified.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. Multi-sensor fusion: Pressure and photoelectric sensors complement each other, overcoming the limitations of a single sensor and improving accuracy to ±2mL.

[0043] 2. Adaptive threshold: Dynamically adjust the alarm threshold to avoid false alarms caused by fluctuations in infusion speed.

[0044] 3. Remote collaborative management: Centralized monitoring of multiple beds can be achieved through wireless networks, reducing the frequency of medical staff inspections.

[0045] 4. Strong compatibility: suitable for infusion bags of different specifications (50mL-1000mL) and various types of liquid medicines (transparent, translucent, opaque).

[0046] 5. The newly added voice broadcast function enhances the recognizability of alarm information through human voice prompts, which can effectively attract the attention of medical staff, especially in noisy environments, and forms a multi-modal alarm synergy with the original buzzer and LED to further reduce the risk of missed reports. At the same time, the voice content supports customization, adapting to the needs of different clinical scenarios and improving the practicality of the system.

[0047] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is a system structure block diagram of this embodiment. DETAILED DESCRIPTION

[0049] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0050] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a component centered. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a component centered. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a component centered. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0052] See also Figure 1 ,Sensor group: It is composed of a pressure sensor array, a photoelectric sensor module, and a temperature compensation module. The pressure sensor array is installed at the load-bearing node of the infusion bag suspension bracket, and the photoelectric sensor module is vertically distributed along the side of the infusion bag;

[0053] Signal processing module: electrically connected to the sensor group, used for filtering, fusing and dynamic threshold calculation of multi-source sensor data;

[0054] Alarm module: includes sound and light alarm unit, wireless communication unit and graded trigger logic. Graded trigger logic triggers different alarm levels according to the liquid level drop rate and remaining amount;

[0055] Power management module: adopts low power consumption design, supports seamless switching between battery power supply and external power supply;

[0056] User interaction interface: includes a touch screen or physical buttons for parameter setting, alarm threshold adjustment and system status display. The pressure sensor array consists of at least 4 piezoresistive sensors arranged in a rectangular array at the four force points of the suspension bracket. After normalization, the output signal of each sensor is calculated using the following formula to calculate the real-time liquid weight: Where W is the estimated value of the liquid weight, Wi is the original reading of the i-th sensor, Ki is the calibration coefficient of the corresponding position, and the calibration coefficient Ki of the pressure sensor array is determined by: recording the baseline value Wi0 of each sensor in the no-load state; loading the standard weight to obtain the full-scale value Wi1 of each sensor; calculating And normalization processing is performed. The photoelectric sensor module includes: at least 8 pairs of infrared transmitting tubes and receiving tubes, which are distributed at equal intervals along the height direction of the infusion bag, and the adjacent spacing is 5-15mm; a wavelength-adjustable light source, the working wavelength range is 850nm-1050nm, and the driving current is adjusted by PWM to switch the wavelength according to the color of the liquid; a light shield structure, covering the outside of the transmitting-receiving tube pair, to reduce ambient light interference. The liquid level judgment logic of the photoelectric sensor module includes: when the light intensity attenuation rate of 3 or more consecutive receiving tubes exceeds the set threshold, it is judged that the liquid level is in this interval; if the deviation between the pressure sensor and the photoelectric sensor liquid level data exceeds 5%, the redundant check is started, and the pressure sensor data is used first. The signal processing module performs the following operations:

[0057] The pressure sensor data is filtered using a sliding average filter with a window size of 0 to 500 sampling points;

[0058] Median filtering is used on the photoelectric sensor data to eliminate instantaneous interference;

[0059] The extended Kalman filter algorithm is used to fuse pressure and photoelectric data to output the estimated value of the liquid level. Its state equation is expressed as:

[0060] x k =x k-1 +Δt·v k-1 +w k

[0061] z k =Hx k +v k

[0062] Dynamic threshold adjustment methods include:

[0063] In the initial stage, a fixed threshold is set according to the nominal capacity of the infusion bag;

[0064] Monitor the liquid level drop rate U within 30 seconds after the start of infusion. If U exceeds the preset range (0.5-5mL / min), it will automatically switch to the adaptive mode. In the adaptive mode, the quadratic curve is fitted with the historical liquid level data to predict the remaining infusion time T. When T <t safe (preset safety time) when the alarm is triggered. The calculation formula of the safety time tsafe is:

[0065]

[0066] Among them, α is the safety factor (0.8-1.2), β is the redundancy time (1-3 minutes), V remaining is the current remaining liquid volume, U is the average infusion speed in the last 10 minutes, and the hierarchical triggering logic of the alarm module includes:

[0067] Level 1 alarm: When the remaining liquid volume is less than 20% of the total capacity, a continuous low-frequency buzzer (frequency 1kHz, interval 2 seconds) and LED slow flashing (cycle 1 second) are triggered;

[0068] Second level alarm: When the remaining liquid volume is less than 5% or the predicted remaining time is less than 5 minutes, a high-frequency buzzer (frequency 3kHz, continuous sounding) and LED flash (cycle 0.3 seconds) are triggered, and an emergency alarm signal is sent to the nurse station and mobile terminal through the wireless communication module;

[0069] Fault alarm: When sensor data is abnormal or communication is interrupted for more than 30 seconds, the red LED will light up and the voice will broadcast "system fault".

[0070] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. The infusion bag liquid level alarm system is characterized by: include: Sensor group: It consists of a pressure sensor array, a photoelectric sensor module, and a temperature compensation module. The pressure sensor array is installed at the load-bearing node of the infusion bag suspension bracket, and the photoelectric sensor module is vertically distributed along the side of the infusion bag; Signal processing module: electrically connected to the sensor group, used for filtering, fusing and dynamic threshold calculation of multi-source sensor data; Alarm module: including an audible and visual alarm unit, a wireless communication unit and a hierarchical trigger logic, wherein the hierarchical trigger logic triggers different alarm levels according to the liquid level drop rate and the remaining amount; Power management module: adopts low power consumption design, supports seamless switching between battery power supply and external power supply; User interaction interface: includes touch screen or physical buttons for parameter setting, alarm threshold adjustment and system status display.

2. The infusion bag liquid level alarm system according to claim 1, characterized in that: The pressure sensor array is composed of at least 4 piezoresistive sensors, which are arranged in a rectangular array at four force-bearing points of the suspension bracket. After the output signal of each sensor is normalized, the real-time liquid weight is calculated by the following formula: Where W is the estimated value of liquid weight, Wi is the original reading of the i-th sensor, and Ki is the calibration coefficient of the corresponding position.

3. The infusion bag liquid level alarm system according to claim 2, characterized in that: The calibration coefficient Ki of the pressure sensor array is determined by: recording the baseline value Wi0 of each sensor in the no-load state; loading a standard weight to obtain the full-scale value Wi1 of each sensor; calculating And normalized.

4. The infusion bag liquid level alarm system according to claim 1, characterized in that: The photoelectric sensor module includes: at least 8 pairs of infrared transmitting tubes and receiving tubes, which are distributed at equal intervals along the height direction of the infusion bag, with adjacent intervals of 5-15mm; a wavelength-adjustable light source with an operating wavelength range of 850nm-1050nm, and the driving current is adjusted by PWM to switch the wavelength according to the color of the drug solution; a light shield structure, covering the outside of the transmitting-receiving tube pair to reduce ambient light interference.

5. The infusion bag liquid level alarm system according to claim 1, characterized in that: The liquid level determination logic of the photoelectric sensor module includes: when the light intensity attenuation rate of three or more consecutive receiving tubes exceeds the set threshold, it is determined that the liquid level is in this interval; if the deviation between the pressure sensor and the photoelectric sensor liquid level data exceeds 5%, redundant verification is started, and the pressure sensor data is used first.

6. The infusion bag liquid level alarm system according to claim 1, characterized in that: The signal processing module performs the following operations: The pressure sensor data is filtered using a sliding average filter with a window size of 0 to 500 sampling points; Median filtering is used on the photoelectric sensor data to eliminate instantaneous interference; The extended Kalman filter algorithm is used to fuse pressure and photoelectric data to output the estimated value of the liquid level. Its state equation is expressed as: x k =x k-1 +Δt·v k-1 +w k z k =Hx k +v k。 7. The infusion bag liquid level alarm system according to claim 1, characterized in that: The dynamic threshold adjustment method comprises: In the initial stage, a fixed threshold is set according to the nominal capacity of the infusion bag; Monitor the liquid level drop rate U within 30 seconds after the start of infusion. If U exceeds the preset range (0.5-5mL / min), it will automatically switch to the adaptive mode. In the adaptive mode, a quadratic curve is fitted with historical liquid level data to predict the remaining infusion time T. When T < t safe (preset safety time) triggers the alarm.

8. The infusion bag liquid level alarm system according to claim 1, characterized in that: The calculation formula of the safety time tsafe is: Among them, α is the safety factor (0.8-1.2), β is the redundancy time (1-3 minutes), V remaining is the current remaining fluid volume, and U is the average infusion rate in the last 10 minutes.

9. The infusion bag liquid level alarm system according to claim 1, characterized in that: The hierarchical triggering logic of the alarm module includes: Level 1 alarm: When the remaining liquid volume is less than 20% of the total capacity, a continuous low-frequency buzzer (frequency 1kHz, interval 2 seconds) and LED slow flashing (cycle 1 second) are triggered; Second level alarm: When the remaining liquid volume is less than 5% or the predicted remaining time is less than 5 minutes, a high-frequency buzzer (frequency 3kHz, continuous sounding) and LED flash (cycle 0.3 seconds) are triggered, and an emergency alarm signal is sent to the nurse station and mobile terminal through the wireless communication module; Fault alarm: When sensor data is abnormal or communication is interrupted for more than 30 seconds, the red LED will light up and the voice will broadcast "system fault". When the first level alarm is triggered, the speaker will play a low-frequency buzzer and a periodic voice prompt "low liquid level, please pay attention"; When the secondary alarm is triggered, it switches to a high-frequency beep and continuously broadcasts the voice "Emergency: The remaining liquid is insufficient, please deal with it immediately"; When a fault alarm occurs, the speaker will play "System fault, please repair" in a loop and the red LED will be on.

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