Patent Publication Number: US-2022233769-A1

Title: Infusion Height Warning and Blocking Device, and Infusion Height Warning and Blocking Method Thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an infusion height warning and blocking device and infusion height warning and blocking method thereof, and more particularly, to an infusion height warning and blocking device and infusion height warning and blocking method thereof capable of utilizing gravity sensors to accurately determine an infusion height difference, and effectively performing different operations for different infusion height differences to maintain a flow rate and avoid a backflow or an excessive flow rate. 
     2. Description of the Prior Art 
     For an infusion device commonly used in medical procedures (such as drips), when a patient is being administered, a height difference between the hand or the arm position and the infusion bottle is less than a certain distance (such as less than 75 to 90 cm) because the needle in the blood vessel makes the patient uncomfortable or the patient moves (to the toilet or walking) with the infusion stand, which will cause the infusion flow rate to slow down, the infusion tube blocked, and even the venous blood backflow. This will not only easily cause the infusion process to be unsmooth, but also require nursing staffs to change the needle and increase patient discomfort. 
     To solve the above problems, the conventional technology uses radio-frequency signals combined with semi-obstructing metal structure as a solution. The principle is that after the patient&#39;s hand is higher than a certain height, the radio-frequency signal from the hand may be above the semi-obstructing metal structure and may be received by the radio-frequency receiver behind to determine that the hand is too high. However, the conventional method lacks a two-stage operation of first warning and then blocking and is not flexible. Besides, it is not easy to block the radio-frequency signal in practical applications. Even if the semi-obstructing metal structure is used to block the radio-frequency signal in specific directions, it is still easy for the receiver to receive the radio-frequency signal after multiple reflections. Therefore, even though there is sufficient high difference between the infusion position and the infusion bottle, the receiver still receives the reflected radio-frequency signal from other directions to cause a false alarm. 
     Therefore, it is necessary to improve the prior art. 
     SUMMARY OF THE INVENTION 
     It is therefore an objective of the present invention to provide an infusion height warning and blocking device and infusion height warning and blocking method thereof capable of utilizing gravity sensors to accurately determine an infusion height difference, and effectively performing different operations for different infusion height differences to maintain a flow rate and avoid a backflow or an excessive flow rate. 
     The present invention discloses an infusion height warning and blocking device for an infusion stand is provided. The infusion height warning and blocking device includes a communication module for receiving at least one sensing signal from at least one gravity sensor; and a processing unit for calculating an infusion height difference between a start position and a usage position according to the at least one sensing signal, and generating at least one height indication signal according to the infusion height difference and at least one height difference threshold. 
     The present invention further discloses an infusion height warning and blocking method for an infusion stand. The infusion height warning and blocking method includes receiving at least one sensing signal from at least one gravity sensor; calculating an infusion height difference between a start position and a usage position according to the at least one sensing signal; and generating at least one height indication signal according to the infusion height difference and at least one height difference threshold. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of an infusion height warning and blocking system and an infusion wearing ring according to an embodiment of the present invention. 
         FIG. 2  to  FIG. 4  are schematic diagrams of operations of the infusion height warning and blocking system and the infusion wearing ring shown in  FIG. 1  utilized for an infusion stand according to an embodiment of the present invention. 
         FIG. 5  is a schematic diagram of a processing unit calculating an infusion height difference when a gravity sensor performs operation shown in  FIG. 3  according to an embodiment of the present invention. 
         FIG. 6  is a schematic diagram of an infusion height warning and blocking process according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Please refer to  FIG. 1 , which is a schematic diagram of an infusion height warning and blocking system  10  and an infusion wearing ring  12  according to an embodiment of the present invention. As shown in  FIG. 1 , the infusion height warning and blocking system  10  includes an infusion height warning and blocking device  100  and at least one gravity sensor  102 ,  104 . The infusion height warning and blocking device  100  is used for an infusion stand, and includes a communication module  106 , a processing unit  108 , an infusion blocker  110 , and a flow rate sensor  112 . In short, the gravity sensors  102 ,  104  detect information such as acceleration, gravity direction, time, etc. to generate at least one sensing signal S 1 , S 2 . The communication module  106  may receive the sensing signals S 1 , S 2  from the gravity sensors  102 ,  104  (e.g., via wireless transmission such as blue tooth and WiFi, or through wired transmission). The processing unit  108  calculates an infusion height difference between a start position (e.g., an outlet of an infusion bottle disposed on an infusion stand) and a usage position (around a position of the infusion wearing ring  12 ) according to the sensing signals S 1 , S 2 , and generates at least one height indication signal H 1 , H 2  according to the infusion height difference and at least one height difference threshold. 
     In detail, in response to the infusion height difference being smaller than a first height difference threshold (such as 75 to 90 cm) of the at least one height difference threshold, the processing unit  108  may generate the height indication signal H 1  for warning (such as warning of insufficient vertical distance via a sound or light signal), so that a patient or a nursing staff may increase the height difference to maintain the flow rate. Furthermore, in response to the infusion height difference being less than a second height difference threshold (e.g. 10 cm) of the at least one height difference threshold or greater than a third height difference threshold (e.g. 100 cm) of the at least one height difference threshold, the processing unit  108  generates the height indication signal H 2  to instruct the infusion blocker  110  to block an infusion tube to stop infusion (the infusion blocker  110  may be a mechanical clamping device for clamping and blocking flow of liquid in the infusion tube), to avoid obstruction, backflow or excessive flow rate (causing overloading on the patient&#39;s heart). As a result, the present invention accurately determines the infusion height difference between the start position and the usage position according to the sensing signals S 1 , S 2  generated by the gravity sensors  102 ,  104 , and effectively performs different operations for different infusion height differences to maintain a flow rate and avoid a backflow or an excessive flow rate. 
     On the other hand, the flow rate sensor  112  detects a current flow rate of an infusion tube (e.g., the flow rate sensor  112  is clamped on the infusion tube, and detects and calculates the flow rate by non-contact methods such as ultrasonic waves), to generate a flow rate sensing signal FS, and the processing unit  108  generates at least one flow rate indication signal F 1 , F 2  according to the flow rate sensing signal FS and at least one flow rate threshold. In this case, in response to the current flow rate being greater or less than a first flow rate threshold of the at least one flow rate threshold by a specific ratio (such as greater than or less than a base flow rate in the initial infusion by 25%), the processing unit  108  may generate the flow rate indication signal F 1  for warning (such as warning of the abnormal infusion rate via a sound or light signal), such that the patient or nursing staff may increase or decrease the height difference or adjust the infusion tube (e.g., unwinding or unbending) to maintain the flow rate. Furthermore, in response to the current flow rate being less than a second flow rate threshold of the at least one flow rate threshold (such as the current flow rate is 0 or backflow), the processing unit  108  generates the flow rate indication signal F 2  to instruct the infusion blocker  110  to block the infusion tube to stop infusion (the infusion blocker  110  may be a mechanical clamping device for clamping and blocking flow of liquid in the infusion tube), to avoid obstruction and backflow. In this way, the present invention may accurately determine the current flow rate of the infusion tube according to the flow rate sensing signal FS generated by the flow rate sensor  112 , and effectively perform different operations for different current flow rates, to maintain the flow rate and avoid obstruction and backflow. 
     Specifically, refer to  FIG. 2  to  FIG. 4 , which are schematic diagrams of operations of the infusion height warning and blocking system  10  and the infusion wearing ring  12  utilized for an infusion stand  20  according to an embodiment of the present invention. First, a nursing staff performs the infusion injection for the patient according to the general operation method (the vertical distance between the infusion bottle and the infusion part of the patient is about 75 to 90 cm), and completes the necessary adjustment of the flow rate during the infusion. Next, as shown in  FIG. 2 , the infusion wearing ring  12  is worn on the infusion part of the patient, and an infusion tube  200  is clamped with the infusion height warning and blocking device  100 . At this time, the infusion tube  200  will pass the infusion blocker  110  and the flow sensor  112 , and the flow sensor  112  may detect the current flow rate of the infusion tube  200  for the processing unit  108  to set as a base flow rate. Continue to  FIG. 3 . After the gravity sensor  104  is removed from the start position (other embodiments may remove the gravity sensor  102 ), the gravity sensor  104  continuously transmits the sensing signal S 2  (generated by detecting acceleration data) to the processing unit  108 . Thus, when the gravity sensor  104  is disposed at a usage position of the infusion wearing ring  12 , the processing unit  108  may continuously calculate the infusion height difference between the start position and the usage position according to the sensing signal S 2 . The infusion height warning and blocking device  100  may charge the gravity sensors  102  and  104  at the start position, so that the gravity sensor  104  may continue to transmit the sensing signal S 2  when removed from the start position and stopped being charged. 
     In this case, as shown in  FIG. 4 , when the patient acts or moves with infusion stand  20  and thus the usage position moves vertically, since the gravity sensor  104  continuously transmits the sensing signal S 2  to the processing unit  108  and the processing unit  108  continuously calculates the infusion height difference between the start position and the usage position, the processing unit  108  may warn the insufficiency of the vertical distance through a sound or light in response to the infusion height difference being less than 75 to 90 cm, so that the patient or a nursing staff may increase the height difference to maintain the flow rate. In addition, in response to the infusion height difference being less than 10 cm or greater than 100 cm, the processing unit  108  may instruct the infusion blocker  110  to block the infusion tube  200  to stop the infusion, so as to avoid obstruction, backflow or excessive flow rate. Then, after the problem is solved and the infusion height difference is greater than 10 cm and less than 100 cm, the processing unit  108  may instruct the infusion blocker  110  to stop blocking the infusion tube  200  to restart the infusion. 
     On the other hand, in response to the current flow rate in the infusion tube  200  being greater than or less than the base flow rate by 25% (or other particular ratios), the processing unit  108  may warn the abnormal infusion rate via a sound or light signal, so that the patient or a nursing staff may increase or decrease the height difference or adjust the infusion tube  200  (such as unwinding or unbending) to maintain the flow rate. In addition, in response to the current flow rate being 0 or backflow, the processing unit  108  may instruct the infusion blocker  110  to block the infusion tube  200  to stop the infusion, so as to avoid obstruction, backflow or excessive flow rate. Noticeably, when the processing unit  108  does not warn that the vertical distance is insufficient or the infusion height difference is not less than 10 cm through a sound or a light signal, if the processing unit  108  determines that the current flow rate is 0 or backflow, and instructs the infusion blocker  110  to block the infusion tube  200 , it means that the current problem about the flow rate is not caused by insufficient infusion height difference (probably due to winding or bending of the infusion tube  200 ), and requires nursing staffs to check conditions of the infusion tube  200  to solve the current problem about the flow rate. After that, when the problem is solved and the flow rate becomes normal, the infusion blocker  110  stops blocking the infusion tube  200  to restart the infusion, and the gravity sensor  104  does not need to return to the start position for reset. 
     It is worth noting that the above-mentioned embodiment mainly accurately determines the infusion height difference between the start position and the usage position according to the sensing signals S 1  and S 2  generated by the gravity sensors  102 ,  104 , and effectively performs different operations for different infusion height differences to maintain the flow rate and avoid backflow or excessive flow rate. Those skilled in the art may make modifications or alterations accordingly, which are not limited to this. For example, in the above embodiment, since the infusion stand  20  may have a vertical height adjustment feature such that the start position is adjustable, although the patient does not move and the usage position is fixed, the gravity sensor  102  disposed at the start position may move up and down with adjustment of the infusion stand  20 . Thus, the gravity sensor  102  may return the sensing signal S 1  related to the acceleration information to the processing unit  108 , and the processing unit  108  calculates the infusion height difference between the start position and the usage position by taking height adjustment of the infusion stand  20  into consideration with original vertical distance between the infusion bottle and the infusion part. In other embodiments, when the height of the infusion stand  20  is not adjusted and the start position is fixed, since the gravity sensor  104  is first disposed at the start position and then disposed at the usage position, the processing unit  108  may calculate the infusion height difference between the start position and the usage position only according to the sensing signal S 2  (that is, only the gravity sensor  104  is required in this embodiment, but in practice, since the height of the infusion stand  20  is often adjusted and the gravity sensors  102  and  104  are often used alternately and are charged via the infusion height warning and blocking device  100 , two gravity sensors  102  and  104  are usually disposed). 
     In addition, please refer to  FIG. 5 , which is a schematic diagram of the processing unit  108  calculating an infusion height difference when the gravity sensor  104  performs operation shown in  FIG. 3  according to an embodiment of the present invention. As shown in  FIG. 5 , when the gravity sensor  104  is removed from the start position, the gravity sensor  104  continues receiving force and transmitting the sensed signal S 2  (generated by detecting acceleration data) to the processing unit  108 . The processing unit  108  calculates the infusion height difference according to a vertical acceleration indicated by the sensing signal S 2  during the moving process of the gravity sensor  104  (in other embodiments, if the position of the gravity sensor  102  also changes, another vertical acceleration indicated by the sensing signal S 1  needs to be considered together). For example, when the gravity sensor  104  receives force and is changed from initial axes X, Y, and Z to axes X′, Y′, Z′, the gravity sensor  104  may detect having an acceleration A and the acceleration A has an angle θ to the vertical direction to the ground, so that the vertical acceleration is A cos θ. The processing unit  108  obtains vertical displacement during the acceleration A from a relation ½A cos θt 2 . By the same token, the processing unit  108  may add up respective vertical displacements of respective vertical accelerations during the moving process to obtain the infusion height difference. 
     In this case, please refer to  FIG. 4  and  FIG. 5  together. The gravity sensor  104  is disposed on the usage position of the infusion wearing ring  12 , such as the wrist. Since the arm length of an adult is about 1 meter (m), when the patient acts to cause the usage position to move up and down as shown in  FIG. 4 , the movement may be considered as an arc with an arm as a radius, for example, when the arm is from a flat position to the highest point and then back to the flat position (i.e. 90-degree arc to and fro), the moving distance is 2*2*3.14*1/4=3.14 meters. If the frequency of the above-mentioned 90-degree arc to and fro is 60 times per minute (that is, 1 time per second), then the moving is 3.14 meters per second. As a result, under a situation that an interval between each data of the sensing signal S 2  generated by the gravity sensor  104  is 1 ms, the gravity sensor  104  equivalently generates each data of the sensing signal S 2  when moving 3.14 mm. In the application of the infusion stand  20 , the processing unit  108  has enough data to determine the movement status of the gravity sensor  104 , and may add up the vertical displacements to obtain the infusion height difference when the patient moves up and down as shown in  FIG. 4 . By the same token, the processing unit  108  also has sufficient amount data to add up the vertical displacements to obtain the infusion height difference when the gravity sensor  104  is removed from the start position and then disposed at the usage position as shown in  FIG. 5 . In some embodiments, a sampling frequency of the sensing signal S 2  may be adjusted according to requirements of calculation amount and sensing sensitivity. For example, the interval between each data of the sensing signal S 2  generated by the gravity sensor  104  may be adjusted to 4 ms, in order to reduce calculation amount of the processing unit  108 ; or, the interval between each data of the sensing signal S 2  generated by the gravity sensor  104  may be adjusted to 0.25 ms, to improve the sensing sensitivity. 
     In addition, please refer to  FIG. 6 , which is a schematic diagram of an infusion height warning and blocking process  60  according to an embodiment of the present invention. As shown in  FIG. 6 , the nursing staff completes adjustment and starts infusion (step  600 ), and turns on the infusion height warning and blocking system  10  (step  602 ). At this moment, the infusion height warning and blocking device  100  detects whether the gravity sensors  102 ,  104  are charged at the start position (step.  604 ). If not, the infusion height warning and blocking device  100  warns that the gravity sensors  102 ,  104  are not homing (step  606 ); if yes, the current flow rate is set as the base flow rate (step  608 ). Then infusion height warning and blocking system  10  starts detection (step  610 ). In terms of height detection, the gravity sensor  104  is removed and disposed at the usage position next to the infusion injection position (step  612 ). The gravity sensors  102 ,  104  report the sensing signals S 1  and S 2  related to acceleration information to the processing unit  108  for calculation (step  614 ), to determine whether the infusion height difference is greater than 75-90 cm (step  616 ). If yes, the infusion blocker  110  conducts the infusion tube (step  618 ); if not, the infusion height warning and blocking device  100  warns that the vertical distance is insufficient (step  620 ). Afterwards, the processing unit  108  determines whether the infusion height difference is less than 10 cm (step  622 ). If not, the infusion height warning and blocking device  100  continues to warn is that the vertical distance is insufficient (step  620 ); if yes, the infusion blocker  110  blocks the infusion tube (step  624 ). 
     In terms of flow rate detection, the flow rate sensor  112  continuously detects the current flow rate of the infusion tube  200  (step  626 ), and the processing unit  108  determines whether the current flow rate is greater than or less than the base flow rate by 25% (step  628 ). If not, the processing unit  108  continuously detects the current flow rate of the infusion tube  200  (step  626 ); if yes, the infusion height warning and blocking device  100  warns the abnormal infusion rate (step  630 ). Further, the processing unit  108  determines whether the current flow rate is 0 or backflow (step  632 ). If not, the processing unit  108  continuously detects the current flow rate of the infusion tube  200  (step  626 ); if yes, the infusion blocker  110  blocks the infusion tube (Step  624 ). For the details of the infusion height warning and blocking process  60 , please refer to the above related descriptions, which are not repeated here for brevity. 
     In addition, the infusion height warning and blocking device  100  may further include a storage unit. The processing unit  108  may be a microprocessor or an application-specific integrated circuit (ASIC). The storage unit may be any data storage device, for storing a program code, and the processing unit  108  reads and executes the program code to complete the above functions and the steps of the infusion height warning and blocking process  60 . The storage unit may be subscriber identity module (SIM), read-only memory (ROM), random-access memory (RAM), CD read-only memory (CD-ROM), magnetic tapes, floppy disks, optical data storage devices, etc., but not limited to these. 
     In summary, the present invention may accurately determine the infusion height difference between the start position and the usage position according to the sensing signals generated by the gravity sensors, and effectively perform different operations for different infusion height differences to maintain a flow rate and avoid a backflow or an excessive flow rate. 
     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.