WO2016180011A1 - 输液器堵塞的识别方法和装置 - Google Patents
输液器堵塞的识别方法和装置 Download PDFInfo
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- WO2016180011A1 WO2016180011A1 PCT/CN2015/096665 CN2015096665W WO2016180011A1 WO 2016180011 A1 WO2016180011 A1 WO 2016180011A1 CN 2015096665 W CN2015096665 W CN 2015096665W WO 2016180011 A1 WO2016180011 A1 WO 2016180011A1
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- pressure
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
- A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
- A61M5/168—Means for controlling media flow to the body or for metering media to the body, e.g. drip meters, counters ; Monitoring media flow to the body
Definitions
- the present invention relates to the field of medical device technology, and in particular, to a method and device for identifying an infusion device clogging.
- the infusion pump is a kind of intelligent instrument that can accurately control the infusion speed and the infusion volume, and can alarm the abnormal situation such as air bubbles, air liquid and infusion tube blockage and automatically cut off the infusion path. It is often used in situations where strict control of infusion volume and dose is required, such as application of booster drugs, antiarrhythmic drugs, intravenous infusion of infants or intravenous anesthesia.
- the infusion set when the infusion set is bent or pressed, the infusion set may be blocked. If it is not discovered in time, it may lead to delay in treatment, resulting in rupture of the infusion tube and infiltration of air. The outflow of blood and the obstruction of the blocked fluid are injected into the body at a rapid rate, which may cause side effects and cause harm to the human body. .
- Pressure sensors are embedded in conventional infusion pumps to detect pressure changes in the infusion tube wall. But because the infusion set is made of PVC (Polyvinyl Chloride, polyvinyl chloride)
- PVC Polyvinyl Chloride, polyvinyl chloride
- the elastic force of the infusion set tube wall will gradually become smaller as time passes after the infusion set is preloaded, so that The pressure of the liquid in the infusion set detected by the pressure sensor is not accurate, so that it is impossible to accurately determine whether the infusion set is blocked.
- a method for identifying an infusion blockage comprising:
- the step of using the curve analysis to obtain an infusion tube wall elastic compensation function comprises:
- the infusion tube wall elastic compensation function is obtained by subtracting the stable pressure value from the detected pressure function.
- the detected pressure function is expressed using a plurality of straight line functions corresponding to a plurality of time periods.
- the detected pressure function is expressed using a parabola.
- the method further includes:
- the pre-pressing time is greater than or equal to the settling time, determining whether the detected pressure corresponding to the pre-pressing time is greater than or equal to the infusion tube alarm pressure threshold;
- the detection pressure corresponding to the preloading time is greater than or equal to the infusion tube alarm pressure threshold, it is confirmed that the current infusion tube is blocked.
- An identification device for clogging an infusion set comprising:
- Obtaining a module configured to obtain a curve corresponding to the detection pressure and the detection time when the unblocked infusion device is pre-stressed;
- An analysis module configured to obtain an elastic force compensation function of the infusion tube wall by using the curve analysis
- the obtaining module is further configured to acquire a stabilization time required when the detection pressure in the curve is stable;
- a detecting module configured to detect whether the current infusion preloading time is less than the stabilization time
- a judging module configured to determine whether a difference between a detection pressure corresponding to the preloading time and a value of an infusion tube wall elastic compensation function is greater than or equal to an infusion tube alarm pressure threshold if the preloading time is less than the stabilization time;
- the confirmation module is configured to confirm that the current infusion tube is blocked if the difference between the detection pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is greater than or equal to the infusion tube alarm pressure threshold.
- the analysis module comprises:
- An analyzing unit configured to obtain a detected pressure function by using the curve analysis
- An obtaining unit configured to obtain a stable pressure value corresponding to the detected pressure in the curve
- a calculating unit configured to obtain the elastic force compensation function of the infusion tube wall by subtracting the stable pressure value by using the detected pressure function.
- the detected pressure function is expressed using a plurality of straight line functions corresponding to a plurality of time periods.
- the detected pressure function is expressed using a parabola.
- the determining module is further configured to: if the pre-pressing time is greater than or equal to the settling time, determine whether the detecting pressure corresponding to the pre-pressing time is greater than or equal to an infusion tube alarm pressure threshold;
- the confirmation module is further configured to confirm that the current infusion tube is blocked if the detection pressure corresponding to the preloading time is greater than or equal to the infusion tube alarm pressure threshold.
- the above-mentioned method and device for identifying the clogging of the infusion set obtains a curve corresponding to the detection pressure of the unblocked infusion device and the detection time; the curve compensation is used to obtain the elastic compensation function of the infusion tube wall; when the detection pressure in the curve is stable The required stabilization time; detecting whether the current infusion preloading time is less than the stabilization time; if yes, determining whether the difference between the detection pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is greater than or equal to the infusion tube alarm pressure threshold; If yes, confirm that the current infusion tube is blocked.
- the infusion tube wall elastic compensation function can reflect the infusion set tube during the infusion set pre-pressure.
- the condition of wall elasticity changes with time. Since the elastic force of the infusion tube wall will gradually decrease and tend to be stable, the stabilization time required for the inelastic tube wall elastic stability can be accurately obtained according to the curve.
- the difference between the detected pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is compared with the infusion tube alarm pressure threshold, if the difference is greater than or equal to the infusion tube
- the alarm pressure threshold confirms that the current infusion set is blocked. Since the detection pressure corresponding to the preloading time minus the value of the elastic force compensation function of the infusion tube wall corresponding to the preloading time, the interference of the elastic change of the infusion tube wall is eliminated, thereby accurately determining whether the infusion set is blocked.
- Figure 1 is a flow chart showing a method of identifying an infusion clogging in an embodiment
- FIG. 3 is a schematic diagram showing a plurality of straight line functions in one embodiment for expressing a curve corresponding to a detection pressure and a detection time;
- FIG. 4 is a schematic structural view of an identification device for clogging an infusion set in an embodiment
- FIG. 5 is a schematic structural diagram of an analysis module in an embodiment.
- a method for identifying an infusion clogging is provided, and the method specifically includes:
- Step 102 Obtain a curve of the detected pressure and the detection time when the unblocked infusion set is pre-stressed.
- the infusion set When detecting the pressure of an unobstructed infusion set, the infusion set is a new infusion set that injects liquid and is properly installed on the infusion pump. Among them, the liquid in the infusion set can be filled. Unobstructed means that the infusion set is not bent or unstressed.
- Preloading refers to the use of a pressure sensor to compress the wall of the infusion set to deform the infusion set. Using a pressure sensor to detect the infusion set, output a detection signal, and pass the detection signal through AD conversion (analogue-to-digital Conversion, analog to digital conversion) to get the detection pressure (indicated by F).
- AD conversion analogue-to-digital Conversion, analog to digital conversion
- the pressure sensor is used to measure the detection pressure when the infusion pump is not started, and the infusion set is pre-stressed when the infusion set is in an unblocked state. According to the detection pressure and the corresponding detection time, the curve of the detection pressure as a function of the detection time is plotted as shown in Fig. 2.
- step 104 the curve compensation is used to obtain the elastic compensation function of the infusion tube wall.
- the change value of the elastic force Fp of the infusion set is equal to the change value of the detection pressure F (expressed by ⁇ F).
- ⁇ Fp ⁇ F.
- step 106 the settling time required when the detected pressure in the curve is stable is obtained.
- the settling time (indicated by ts) is the initial time after the detection pressure in the curve is stabilized, that is, the minimum time corresponding to the steady pressure value in the curve. Due to the large deformation of the infusion set during preloading, the stable pressure value is not affected by the deformation of the infusion set due to packaging or compression.
- Step 108 Detect whether the current infusion preload time is less than the stabilization time; if yes, proceed to step 110, otherwise, compare the detection pressure corresponding to the preload time with the infusion tube alarm pressure threshold.
- the current infusion set refers to the infusion set that is being infused during the operation of the infusion pump.
- the pressure sensor is used to detect the current infusion preloading time. If the preloading time is less than the settling time, it indicates that the current infusion tube wall elastic force changes with the preloading time. .
- Step 110 determining whether the difference between the detection pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is greater than or equal to the infusion tube alarm pressure threshold; if yes, proceeding to step 112, otherwise, continuing to obtain the corresponding preloading time detection pressure.
- the current infusion set is detected by a pressure sensor, and the detection pressure corresponding to the preloading time is obtained. Calculate the value of the elastic force compensation function of the infusion tube wall corresponding to the preloading time.
- the detection pressure corresponding to the pre-pressurization time of the current infusion device is subtracted from the elastic force compensation function value of the infusion tube wall corresponding to the pre-pressure time, and the difference corresponding to the pre-compression time is obtained. Thereby eliminating the interference of the elastic force change of the infusion tube wall, and accurately reflecting the condition of the liquid pressure inside the infusion set corresponding to the preloading time.
- step 112 it is confirmed that the current infusion tube is blocked.
- the curve of the detection pressure and the detection time when the unblocked infusion device is pre-pressed is obtained; the elastic force compensation function of the infusion set tube wall is obtained by curve analysis; the stabilization time required for the detection pressure in the curve is obtained; Whether the current infusion preloading time is less than the stabilization time; if yes, determining whether the difference between the detection pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is greater than or equal to the infusion tube alarm pressure threshold; if yes, confirming the current infusion The tube is blocked.
- the infusion tube wall elastic compensation function can reflect the infusion set tube during the infusion set pre-pressure.
- the condition of wall elasticity changes with time. Since the elastic force of the infusion tube wall will gradually decrease and tend to be stable, the stabilization time required for the inelastic tube wall elastic stability can be accurately obtained according to the curve.
- the difference between the detected pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is compared with the infusion tube alarm pressure threshold, if the difference is greater than or equal to the infusion tube
- the alarm pressure threshold confirms that the current infusion set is blocked. Since the detection pressure corresponding to the preloading time minus the value of the elastic force compensation function of the infusion tube wall corresponding to the preloading time, the interference of the elastic change of the infusion tube wall is eliminated, thereby accurately determining whether the infusion set is blocked.
- the step of obtaining the inelastic tube wall elastic compensation function by using the curve analysis comprises: using the curve analysis to obtain the detected pressure function; obtaining the corresponding stable pressure value when the detected pressure is stable in the curve; and using the detected pressure function to subtract the stable pressure The value obtains the elastic compensation function of the infusion tube wall.
- the stable coordinate corresponding to the detected pressure in the curve Take the stable coordinate corresponding to the detected pressure in the curve, that is, the coordinate corresponding to the stable pressure value (represented by Fs) and the stabilization time (expressed by ts).
- the stable coordinate can be expressed as (ts, Fs). Due to the large deformation of the infusion set during preloading, the stable pressure value is not affected by the deformation of the infusion set due to packaging or compression.
- the approximate processing is used to analyze the function of the detected pressure as a function of time.
- the detected pressure function is expressed using a plurality of linear functions corresponding to the plurality of time periods.
- the segmentation line is used to divide the detection time into a plurality of time segments, and each time segment corresponds to a straight line function.
- t the detection time
- F(t) the detection pressure
- k the slope corresponding to the curve in the time period
- b is a constant.
- the time period in which the detected pressure in the curve changes significantly with the detection time it can be further subdivided into a plurality of sub-time segments, each of which has a corresponding sub-linear function.
- FIG. 3 a schematic diagram of a curve in which the detected pressure corresponds to the detection time is expressed as a plurality of straight line functions.
- the detected pressure function is expressed using a parabola.
- the curve can be approximated by a parabola with an opening to the right. That is, within the settling time, a parabola is used to approximate the curve of the detected pressure and the detection time.
- ⁇ Fp(t) ⁇ F(t)
- the method further comprises: if the preloading time is greater than or equal to the stabilizing time, determining whether the detecting pressure corresponding to the preloading time is greater than or equal to the infusion tube The alarm pressure threshold; if the detection pressure corresponding to the preloading time is greater than or equal to the infusion tube alarm pressure threshold, the current infusion tube is blocked.
- the infusion set tube wall elastic force has reached the stable elastic force value Fps, so there is no need to subtract the change value of the infusion set tube wall elastic force with time ⁇ Fp(t) It is no longer necessary to subtract ⁇ F(t), and the detection pressure corresponding to the preloading time can be compared with the infusion tube alarm pressure threshold. If the detection pressure corresponding to the preloading time is greater than or equal to the infusion tube alarm pressure threshold, the current infusion is confirmed. The tube is blocked. This makes it possible to accurately identify whether the infusion tube is blocked.
- an apparatus for identifying an infusion set comprising: an acquisition module 402, an analysis module 404, a detection module 406, a determination module 408, and a confirmation module 410, wherein:
- the obtaining module 402 is configured to obtain a curve corresponding to the detection pressure when the unplugged infusion device is pre-stressed.
- the analysis module 404 is configured to obtain an infusion tube wall elastic compensation function by using curve analysis.
- the acquisition module 402 is also used to obtain the settling time required when the detected pressure in the curve is stable.
- the detecting module 406 is configured to detect whether the current infusion preload time is less than a settling time.
- the determining module 408 is configured to determine whether the difference between the detected pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is greater than or equal to the infusion tube alarm pressure threshold if the preloading time is less than the settling time.
- the confirmation module 410 is configured to confirm that the current infusion tube is blocked if the difference between the detection pressure corresponding to the preloading time and the value of the infusion tube wall elastic compensation function is greater than or equal to the infusion tube alarm pressure threshold.
- the analysis module 404 includes an analysis unit 404a, an acquisition unit 404b, and a calculation unit 404c, wherein:
- the analyzing unit 404a is configured to obtain a detected pressure function by using curve analysis.
- the detected pressure function is expressed using a plurality of linear functions corresponding to the plurality of time periods.
- the detected pressure function is expressed using a parabola.
- the obtaining unit 404b is configured to acquire a stable pressure value corresponding to the detected pressure in the curve when the pressure is stable.
- the calculating unit 404c is configured to obtain the infusion tube wall elastic compensation function by using the detected pressure function minus the stable pressure value.
- the determining module 408 is further configured to: if the pre-pressing time is greater than or equal to the settling time, determine whether the detecting pressure corresponding to the pre-pressing time is greater than or equal to the infusion tube alarm pressure threshold; and the confirming module 410 is further configured to pre-press If the detection pressure corresponding to the time is greater than or equal to the infusion tube alarm pressure threshold, the current infusion tube is blocked.
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Abstract
一种输液器堵塞的识别方法，包括：获取未阻塞的输液器预压时的检测压力与检测时间对应的曲线（步骤102）；利用曲线分析得到输液器管壁弹力补偿函数（步骤104）；获取曲线中的检测压力稳定时所需的稳定时间（步骤106）；检测当前输液器预压时间是否小于稳定时间（步骤108）；若是，则判断预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值（步骤110）；若是，则确认当前输液管阻塞。采用本方法能够消除输液管壁弹力变化的干扰，准确判断输液器是否堵塞。此外还提供一种输液器堵塞的识别装置。
Description
【技术领域】
本发明涉及医疗器械技术领域，特别是涉及一种输液器堵塞的识别方法和装置。
【背景技术】
输液泵是一种可精确控制输液速度和输液量，并且能对气泡、空液、输液管阻塞等异常情况进行报警并自动切断输液通路的一种智能仪器。常用于需要严格控制输液量和药量的情况，如在应用升压药物，抗心律失常药药物，婴幼儿静脉输液或静脉麻醉等。
在输液操作过程中，输液器发生弯折或被压等情况时，会造成输液器堵塞。如未及时发现，可能导致贻误治疗时机，导致输液管破裂而出现空气的内渗，血液的外流，阻塞产生的阻塞液体以很快的速度注入到人体内，可能产生副作用，给人体带来危害。传统的输液泵中嵌有压力传感器来检测输液器管壁的压力变化。但由于输液器以PVC（Polyvinyl
chloride，聚氯乙烯）
为主要原料生产制作，当输液器发生一定形变时输液器管壁具有相应的弹力，并且弹力随着时间的推移会逐渐变小。所以，通过监测输液器管壁弹力的方式来监测输液器内液体压力时，在输液器被预压开始的一段时间内，由于输液器管壁弹力会随时间的推移而慢慢变小，使得压力传感器检测到的输液器内液体压力并不准确，以致无法准确判断输液器是否堵塞。
【发明内容】
基于此，有必要针对上述技术问题，提供一种能够消除输液管壁弹力变化的干扰，准确判断输液器是否堵塞的输液器堵塞的识别方法和装置。
一种输液器堵塞的识别方法，所述方法包括：
获取未阻塞的输液器预压时的检测压力与检测时间对应的曲线；
利用所述曲线分析得到输液器管壁弹力补偿函数；
获取所述曲线中的检测压力稳定时所需的稳定时间；
检测当前输液器预压时间是否小于所述稳定时间；
若是，则判断所述预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值；
若是，则确认所述当前输液管阻塞。
在其中一个实施例中，所述利用所述曲线分析得到输液器管壁弹力补偿函数的步骤包括：
利用所述曲线分析得到检测压力函数；
获取所述曲线中检测压力稳定时对应的稳定压力值；
利用所述检测压力函数减去所述稳定压力值得到所述输液器管壁弹力补偿函数。
在其中一个实施例中，所述检测压力函数采用多个时间段对应的多个直线函数来表达。
在其中一个实施例中，所述检测压力函数采用抛物线来表达。
在其中一个实施例中，在所述检测当前输液器预压时间是否小于所述稳定时间的步骤之后，还包括：
若所述预压时间大于或等于所述稳定时间，则判断所述预压时间对应的检测压力是否大于或等于输液管报警压力阈值；
若所述预压时间对应的检测压力大于或等于输液管报警压力阈值，则确认所述当前输液管阻塞。
一种输液器堵塞的识别装置，所述装置包括：
获取模块，用于获取未阻塞的输液器预压时的检测压力与检测时间对应的曲线；
分析模块，用于利用所述曲线分析得到输液器管壁弹力补偿函数；
所述获取模块还用于获取所述曲线中的检测压力稳定时所需的稳定时间；
检测模块，用于检测当前输液器预压时间是否小于所述稳定时间；
判断模块，用于若预压时间小于所述稳定时间判断所述预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值；
确认模块，用于若所述预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值大于或等于输液管报警压力阈值，则确认所述当前输液管阻塞。
在其中一个实施例中，所述分析模块包括：
分析单元，用于利用所述曲线分析得到检测压力函数；
获取单元，用于获取所述曲线中检测压力稳定时对应的稳定压力值；
计算单元，用于利用所述检测压力函数减去所述稳定压力值得到所述输液器管壁弹力补偿函数。
在其中一个实施例中，所述检测压力函数采用多个时间段对应的多个直线函数来表达。
在其中一个实施例中，所述检测压力函数采用抛物线来表达。
在其中一个实施例中，所述判断模块还用于若所述预压时间大于或等于所述稳定时间，则判断所述预压时间对应的检测压力是否大于或等于输液管报警压力阈值；所述确认模块还用于若所述预压时间对应的检测压力大于或等于输液管报警压力阈值，则确认所述当前输液管阻塞。
上述输液器堵塞的识别方法和装置，获取未阻塞的输液器预压时的检测压力与检测时间对应的曲线；利用曲线分析得到输液器管壁弹力补偿函数；获取曲线中的检测压力稳定时所需的稳定时间；检测当前输液器预压时间是否小于稳定时间；若是，则判断预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值；若是，则确认当前输液管阻塞。由于输液器管壁弹力补偿函数是利用未阻塞的输液器预压时的检测压力与检测时间的曲线分析得到的，因此输液器管壁弹力补偿函数能够反映出在输液器预压时输液器管壁弹力随时间变化的状况。由于输液器管壁弹力都会逐渐减小并趋于稳定，因此能够根据该曲线准确得到输液器管壁弹力稳定时所需的稳定时间。如果输液器预压时间小于稳定时间，则根据该预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值与输液管报警压力阈值进行比较，如果该差值大于或等于输液管报警压力阈值，则确认当前输液器被堵塞。由于该预压时间对应的检测压力减去了该预压时间对应的输液器管壁弹力补偿函数值，由此消除了输液管壁弹力变化的干扰，从而准确判断出输液器是否堵塞。
【附图说明】
图1为一个实施例中输液器堵塞的识别方法的流程图；
图2为一个实施例中检测压力与检测时间对应的曲线；
图3为一个实施例中多个直线函数来表达检测压力与检测时间对应的曲线的示意图；
图4为一个实施例中输液器堵塞的识别装置的结构示意图；
图5为一个实施例中分析模块的结构示意图。
【具体实施方式】
为了使本发明的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本发明进行进一步详细说明。应当理解，此处描述的具体实施例仅仅用以解释本发明，并不用于限定本发明。
在一个实施例中，如图1所示，提供了一种输液器堵塞的识别方法，该方法具体包括：
步骤102，获取未阻塞的输液器预压时的检测压力与检测时间的曲线。
检测未阻塞的输液器的压力时，输液器是注入液体的新输液器，并且正确安装在输液泵上。其中，输液器内的液体可以是装满的。未阻塞是指输液器未发生弯折或未被压。预压是指利用压力传感器压迫输液器管壁使得输液器发生变形。利用压力传感器来检测输液器，输出检测信号，将检测信号经过AD转换（analogue-to-digital
conversion，模拟数字转换）得到检测压力（用F来表示）。利用压力传感器测出输液泵在未启动时，且输液器在未阻塞的状态下时输液器预压时的检测压力。根据检测压力与对应的检测时间绘制出检测压力随检测时间变化的曲线如图2所示。
步骤104，利用曲线分析得到输液器管壁弹力补偿函数。
由于输液器内注入液体后会产生两个压力，即输液器内部液体压力（用F1来表示）与输液器管壁弹力（用Fp来表示）。因此检测压力等于输液器内部液体压力与输液器管壁弹力之和，即F
= F1 +
Fp。当输液器内部液体压力F1一定时，输液器管壁弹力Fp的变化值（用ΔFp来表示，即输液器管壁弹力补偿函数）也就与检测压力F的变化值（用ΔF来表示）相等，即ΔFp
=
ΔF。输液泵在未启动时，且输液器在未阻塞的状态下时，输液器内部液体压力F1保持不变。根据曲线可知，检测压力F逐渐趋于稳定，即达到一个稳定压力值（用Fs来表示）。由于检测压力等于输液器内部液体压力与输液器管壁弹力输液器管壁弹力之和，输液器内部液体压力保持不变，也就是F
= F1 +
Fp，且F1保持不变，因此输液器管壁弹力Fp也会逐渐趋于稳定，即达到某一个稳定弹力值（用Fps来表示）。获取曲线中的坐标值，例如原点坐标和稳定压力值对应的坐标等，采用近似处理的方式得到检测压力函数，利用检测压力函数与稳定压力值的差值得到检测压力F的变化值，从而得到输液器管壁弹力补偿函数。
步骤106，获取曲线中的检测压力稳定时所需的稳定时间。
稳定时间（用ts来表示）是指曲线中的检测压力稳定后的初始时间，也就是曲线中稳定压力值对应的最小时间。由于输液器预压时会产生较大形变，所以稳定压力值不会受到输液器因包装或受压而造成的形变影响。
步骤108，检测当前输液器预压时间是否小于稳定时间；若是，则进入步骤110，否则，将预压时间对应的检测压力与输液管报警压力阈值进行比较。
当前输液器是指输液泵运行中正在输液的输液器，利用压力传感器检测当前输液器预压时间，如果预压时间小于稳定时间，则表示当前输液器管壁弹力在随着预压时间而变化。
步骤110，判断预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值；若是，则进入步骤112，否则，继续获取预压时间对应的检测压力。
利用压力传感器检测当前的输液器，得到预压时间对应的检测压力。计算该预压时间对应的输液器管壁弹力补偿函数值。将当前输液器预压时间对应的检测压力减去预压时间对应的输液器管壁弹力补偿函数值，得到预压时间对应的差值。从而消除了输液器管壁弹力变化的干扰，能够准确反映出预压时间对应的输液器内部液体压力的状况。
步骤112，确认当前输液管阻塞。
如果该差值大于或等于输液管报警压力阈值，则可以确认当前输液管被堵塞。
本实施例中，获取未阻塞的输液器预压时的检测压力与检测时间的曲线；利用曲线分析得到输液器管壁弹力补偿函数；获取曲线中的检测压力稳定时所需的稳定时间；检测当前输液器预压时间是否小于稳定时间；若是，则判断预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值；若是，则确认当前输液管阻塞。由于输液器管壁弹力补偿函数是利用未阻塞的输液器预压时的检测压力与检测时间的曲线分析得到的，因此输液器管壁弹力补偿函数能够反映出在输液器预压时输液器管壁弹力随时间变化的状况。由于输液器管壁弹力都会逐渐减小并趋于稳定，因此能够根据该曲线准确得到输液器管壁弹力稳定时所需的稳定时间。如果输液器预压时间小于稳定时间，则根据该预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值与输液管报警压力阈值进行比较，如果该差值大于或等于输液管报警压力阈值，则确认当前输液器被堵塞。由于该预压时间对应的检测压力减去了该预压时间对应的输液器管壁弹力补偿函数值，由此消除了输液管壁弹力变化的干扰，从而准确判断出输液器是否堵塞。
在一个实施例中，利用曲线分析得到输液器管壁弹力补偿函数的步骤包括：利用曲线分析得到检测压力函数；获取曲线中检测压力稳定时对应的稳定压力值；利用检测压力函数减去稳定压力值得到输液器管壁弹力补偿函数。
获取曲线中的坐标值，例如原点坐标和稳定压力值对应的坐标等。原点坐标也就是曲线中未阻塞的输液器在预压时得到的第一个检测压力值（用F0来表示），与对应的检测时间（用t0来表示），原点坐标可以表示为（t0，F0），一般取t0
=
0。由于输液器本身因为包装或受压等产生的形变会造成输液器管壁弹力发生改变，未阻塞的输液器首次预压时的第一个检测压力值会存在差异。取曲线中检测压力稳定时对应的稳定坐标，也就是曲线中稳定压力值（用Fs来表示）与稳定时间（用ts来表示）对应的坐标，稳定坐标可以表示为（ts，Fs）。由于输液器预压时会产生较大形变，所以稳定压力值不会受到输液器因包装或受压而造成的形变影响。采用近似处理的方式来分析得到检测压力随时间变化的函数。
在其中一个实施例中，检测压力函数采用多个时间段对应的多个直线函数来表达。具体的，采用分段直线的方法，将检测时间分为多个时间段，每个时间段分别对应一个直线函数。直线函数可以表达为F(t)
= kt +
b，其中t为检测时间，F(t)为检测压力，k为时间段内曲线对应的斜率，b为常数。对于曲线中检测压力随检测时间变化明显的时间段，可以再进一步细分为多个子时间段，每个子时间段分别具有对应的子直线函数。如图3所示，为多个直线函数来表达检测压力与检测时间对应的曲线的示意图。
在另一个实施例中，检测压力函数采用抛物线来表达。具体的，可以采用开口向右的抛物线对曲线进行近似处理。也就是稳定时间之内，采用抛物线来近似表达检测压力与检测时间的曲线。其中抛物线可以表达为F(t)
= at2 + bt + c，其中t为检测时间，F(t)为检测压力，a、b、c分别为常数。
根据检测压力F等于输液器内部液体压力F1与输液器管壁弹力输液器管壁弹力Fp之和，也就是F = F1 +
Fp，在输液器内部液体压力F1保持不变的情况下，输液器管壁弹力Fp的变化值ΔFp等于检测压力F的变化值ΔF，即ΔFp =
ΔF，也就是输液器管壁弹力随时间的变化值ΔFp(t)（ 即输液器管壁弹力补偿函数）等于检测压力随时间的变化值ΔF(t)，即ΔFp(t) =
ΔF(t)。检测压力随时间的变化值ΔF(t)等于检测压力函数F(t)减去稳定压力值Fs，即ΔF(t) = F(t)
–Fs，因此输液器管壁弹力补偿函数为ΔFp(t) = F(t) –Fs。
假设未阻塞的输液器预压开始后在稳定时间内，输液器管壁弹力随时间变化的弹力值为Fp(t)，由于输液器管壁弹力最终会稳定于稳定弹力值Fps，可以得到输液器管壁弹力补偿函数为ΔFp(t)
= Fp(t) –Fps。根据F = Fl + Fp，则可以得到F1= F–Fp，也就是当前输液器内部液体压力F1 = F(t) -
Fp(t)。再根据ΔFp(t) = ΔF(t)，因此能够得到F(t) -ΔF(t) = Fl + Fp(t) - ΔFp(t) = Fl + Fp(t) -
( Fp(t) - Fps ) = Fl + Fps，即F(t) -ΔF(t) = Fl + Fps，也就是F(t) -ΔFp(t) = Fl +
Fps。由于Fps为定值，所以F(t) - ΔFp(t)
即预压时间对应的检测压力减去了该预压时间对应的输液器管壁弹力补偿函数值消除了输液器管壁弹力变化的干扰，从而能够准确反映出稳定时间内输液器管内液体压力的变化情况。
在一个实施例中，在检测当前输液器预压时间是否小于稳定时间的步骤之后，还包括：若预压时间大于或等于稳定时间，则判断预压时间对应的检测压力是否大于或等于输液管报警压力阈值；若预压时间对应的检测压力大于或等于输液管报警压力阈值，则确认当前输液管阻塞。
本实施例中，如果当前输液器预压时间大于稳定时间，则输液器管壁弹力已达到稳定弹力值Fps，因此无需再减去输液器管壁弹力随时间的变化值ΔFp(t)也就是无需再减去ΔF(t)，可以用预压时间对应的检测压力与输液管报警压力阈值之间进行比较，如果预压时间对应的检测压力大于或等于输液管报警压力阈值，则确认当前输液管阻塞。由此能够准确识别出输液管是否阻塞。
如图4所示，在一个实施例中，提供了一种输液器堵塞的识别装置，该装置包括：获取模块402、分析模块404、检测模块406、判断模块408和确认模块410，其中：
获取模块402，用于获取未阻塞的输液器预压时的检测压力与检测时间对应的曲线。
分析模块404，用于利用曲线分析得到输液器管壁弹力补偿函数。
获取模块402还用于获取曲线中的检测压力稳定时所需的稳定时间。
检测模块406，用于检测当前输液器预压时间是否小于稳定时间。
判断模块408，用于若预压时间小于稳定时间判断预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值。
确认模块410，用于若预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值大于或等于输液管报警压力阈值，则确认当前输液管阻塞。
在一个实施例中，如图5所示，分析模块404包括：分析单元404a、获取单元404b和计算单元404c，其中：
分析单元404a，用于利用曲线分析得到检测压力函数。在其中一个实施例中，检测压力函数采用多个时间段对应的多个直线函数来表达。在另一个实施例中，检测压力函数采用抛物线来表达。
获取单元404b，用于获取曲线中检测压力稳定时对应的稳定压力值。
计算单元404c，用于利用检测压力函数减去稳定压力值得到输液器管壁弹力补偿函数。
在一个实施例中，判断模块408还用于若预压时间大于或等于稳定时间，则判断预压时间对应的检测压力是否大于或等于输液管报警压力阈值；确认模块410还用于若预压时间对应的检测压力大于或等于输液管报警压力阈值，则确认当前输液管阻塞。
以上所述实施例的各技术特征可以进行任意的组合，为使描述简洁，未对上述实施例中的各个技术特征所有可能的组合都进行描述，然而，只要这些技术特征的组合不存在矛盾，都应当认为是本说明书记载的范围。
以上所述实施例仅表达了本发明的几种实施方式，其描述较为具体和详细，但并不能因此而理解为对发明专利范围的限制。应当指出的是，对于本领域的普通技术人员来说，在不脱离本发明构思的前提下，还可以做出若干变形和改进，这些都属于本发明的保护范围。因此，本发明专利的保护范围应以所附权利要求为准。
Claims (10)
- 一种输液器堵塞的识别方法，所述方法包括：获取未阻塞的输液器预压时的检测压力与检测时间对应的曲线；利用所述曲线分析得到输液器管壁弹力补偿函数；获取所述曲线中的检测压力稳定时所需的稳定时间；检测当前输液器预压时间是否小于所述稳定时间；若是，则判断所述预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值；若是，则确认所述当前输液管阻塞。
- 根据权利要求1所述的方法，其特征在于，所述利用所述曲线分析得到输液器管壁弹力补偿函数的步骤包括：利用所述曲线分析得到检测压力函数；获取所述曲线中检测压力稳定时对应的稳定压力值；利用所述检测压力函数减去所述稳定压力值得到所述输液器管壁弹力补偿函数。
- 根据权利要求2所述的方法，其特征在于，所述检测压力函数采用多个时间段对应的多个直线函数来表达。
- 根据权利要求2所述的方法，其特征在于，所述检测压力函数采用抛物线来表达。
- 根据权利要求1-4任一项所述的方法，其特征在于，在所述检测当前输液器预压时间是否小于所述稳定时间的步骤之后，还包括：若所述预压时间大于或等于所述稳定时间，则判断所述预压时间对应的检测压力是否大于或等于输液管报警压力阈值；若所述预压时间对应的检测压力大于或等于输液管报警压力阈值，则确认所述当前输液管阻塞。
- 一种输液器堵塞的识别装置，其特征在于，所述装置包括：获取模块，用于获取未阻塞的输液器预压时的检测压力与检测时间对应的曲线；分析模块，用于利用所述曲线分析得到输液器管壁弹力补偿函数；所述获取模块还用于获取所述曲线中的检测压力稳定时所需的稳定时间；检测模块，用于检测当前输液器预压时间是否小于所述稳定时间；判断模块，用于若预压时间小于所述稳定时间判断所述预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值是否大于或等于输液管报警压力阈值；确认模块，用于若所述预压时间对应的检测压力与输液器管壁弹力补偿函数值的差值大于或等于输液管报警压力阈值，则确认所述当前输液管阻塞。
- 根据权利要求2所述的装置，其特征在于，所述分析模块包括：分析单元，用于利用所述曲线分析得到检测压力函数；获取单元，用于获取所述曲线中检测压力稳定时对应的稳定压力值；计算单元，用于利用所述检测压力函数减去所述稳定压力值得到所述输液器管壁弹力补偿函数。
- 根据权利要求7所述的装置，其特征在于，所述检测压力函数采用多个时间段对应的多个直线函数来表达。
- 根据权利要求7所述的装置，其特征在于，所述检测压力函数采用抛物线来表达。
- 根据权利要求6-9任一项所述的装置，其特征在于，所述判断模块还用于若所述预压时间大于或等于所述稳定时间，则判断所述预压时间对应的检测压力是否大于或等于输液管报警压力阈值；所述确认模块还用于若所述预压时间对应的检测压力大于或等于输液管报警压力阈值，则确认所述当前输液管阻塞。
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| CN111683700A (zh) * | 2017-11-16 | 2020-09-18 | 费森尤斯维尔公司 | 用于向患者施用医用流体的输注装置及方法 |
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| CN112557282A (zh) * | 2020-11-17 | 2021-03-26 | 深圳市科曼医疗设备有限公司 | 一种血球分析仪的小孔堵孔识别方法和装置 |
| CN112857821A (zh) * | 2020-12-24 | 2021-05-28 | 联合汽车电子有限公司 | 燃油分配管总成失效识别装置及其失效识别方法 |
| CN113640354A (zh) * | 2021-08-27 | 2021-11-12 | 重庆中元汇吉生物技术有限公司 | 堵针检测方法、装置、设备及存储介质 |
| US11957542B2 (en) | 2020-04-30 | 2024-04-16 | Automed Patent Holdco, Llc | Sensing complete injection for animal injection device |
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| CN104815368B (zh) * | 2015-05-14 | 2018-04-06 | 深圳市科曼医疗设备有限公司 | 输液器堵塞的识别方法和装置 |
| CN105396200B (zh) * | 2015-12-08 | 2021-11-05 | 深圳迈瑞科技有限公司 | 输液泵及其输液管路上阻塞报警方法和装置 |
| CN105521532A (zh) * | 2016-01-26 | 2016-04-27 | 北京英诺达医疗科技有限公司 | 注射泵的阻塞检测装置及方法 |
| CN106421975A (zh) * | 2016-07-27 | 2017-02-22 | 珠海市美瑞华医用科技有限公司 | 一种儿童医疗泵系统和装置 |
| US10485926B2 (en) | 2016-10-07 | 2019-11-26 | Carefusion 303, Inc. | Systems and methods for controlling an infusion pump |
| WO2022067500A1 (zh) * | 2020-09-29 | 2022-04-07 | 深圳市科曼医疗设备有限公司 | 输液泵阻塞压力检测方法、装置、设备和介质 |
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| CN112423805B (zh) * | 2018-07-18 | 2023-01-31 | 深圳迈瑞科技有限公司 | 输液报警系统、方法、计算机设备和存储介质 |
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| CN112857821A (zh) * | 2020-12-24 | 2021-05-28 | 联合汽车电子有限公司 | 燃油分配管总成失效识别装置及其失效识别方法 |
| CN113640354A (zh) * | 2021-08-27 | 2021-11-12 | 重庆中元汇吉生物技术有限公司 | 堵针检测方法、装置、设备及存储介质 |
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