24-hour urine total nitrogen automatic measuring device

Abstract

The invention provides a 24-hour urine total nitrogen automatic measuring device, which comprises an automatic urine collection module, which is used for continuously introducing urine of a patient into a disposable collection bag in a closed-loop path and homogenizing and weighing the urine in the bag; the automatic sampling module is communicated with a liquid path of the automatic urine collecting module and is used for extracting the homogenized urine in a creeping manner and injecting a sample with a fixed volume into the reaction cabin; the nitrogenous organic matter conversion and ammonia gas measurement module is hermetically connected to the downstream of the automatic sampling module and is used for completely converting a nitrogen source in the sample into ammonia gas and detecting the mass concentration of the ammonia gas in real time; the interaction and total nitrogen calculation module is in signal connection with the three modules and is used for receiving the ammonia gas mass concentration data and automatically calculating and outputting a total nitrogen result of urine by combining the ammonia gas mass concentration data with the 24-hour urine volume; the collection module, the sampling module and the conversion and measurement module are sequentially connected according to the flow direction of urine, and the interaction and total nitrogen calculation module performs cross-module control and synchronizes data to form a closed-loop full-automatic detection path.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of medical devices, and particularly relates to a 24-hour urine total nitrogen automatic measuring device. BACKGROUND

[0002] 24-hour urine total nitrogen is an important biochemical indicator for evaluating the protein metabolism level and nutritional status of the human body, and is widely used in clinical nutritional assessment, intensive care management, and metabolic monitoring of patients with chronic diseases. The traditional urine total nitrogen detection method represented by the Kjeldahl method has the advantages of accurate measurement and measurement results not affected by other impurities in urine. However, the operation process is complicated, the detection time is long, and the professional quality of the operator and the experimental environment are required to be high, which is difficult to meet the clinical detection requirements of high frequency and high efficiency. Especially in the ICU, postoperative rehabilitation or long-term bedridden patient groups, due to limited activities, urine collection is difficult, and the traditional detection method relies on manual urine sample collection, which may cause sample pollution and increase the nursing burden. In addition, due to the lack of an integrated device that can realize bedside automatic sampling, automatic detection and output of results, the widespread promotion and application of urine total nitrogen monitoring in clinical nursing are seriously restricted. With the development of modern medical detection technology, integration, intelligence and non-invasive real-time detection have become the core direction of the development of clinical equipment. Therefore, it is urgent to develop a full-automatic device suitable for bedridden patients for automatic urine collection, automatic sampling and accurate total nitrogen determination to improve detection efficiency, reduce the work intensity of medical staff and improve the patient care experience. SUMMARY

[0003] The problem to be solved by the present application is that the existing urine total nitrogen detection method has the problems of complicated operation process, low detection efficiency, high dependence on experimental environment and professional personnel, and the measurement results are affected by factors such as operation conditions and titration end point. In particular, in the clinical application of bedridden patients, the traditional method needs to manually collect 24-hour urine and perform complex chemical digestion and determination analysis, which is time-consuming and labor-intensive. The measurement results are affected by factors such as operation conditions and titration end point, and it is difficult to realize automatic and standardized 24-hour urine total nitrogen determination for bedridden patients. Therefore, the present application provides a 24-hour urine total nitrogen automatic measuring device, which aims to realize 24-hour continuous collection, quantitative sampling, nitrogen-containing organic matter conversion, ammonia detection and total nitrogen calculation of urine, so as to realize full-automatic, accurate and efficient measurement of 24-hour urine total nitrogen, and improve the intelligence and clinical adaptability of detection.

[0004] The specific technical solution is: a 24-hour urine total nitrogen automatic measuring device, comprising:

[0005] An automatic urine collection module for continuously guiding the urine of a patient into a disposable collection bag through a closed loop path and homogenizing and weighing the urine in the bag;

[0006] An automatic sampling module in liquid communication with the automatic urine collection module for extracting the homogenized urine in a peristaltic manner and injecting a fixed volume of sample into a reaction chamber;

[0007] A nitrogen-containing organic matter conversion and ammonia measurement module connected to the downstream of the automatic sampling module in a sealed manner for converting all nitrogen sources in the sample into ammonia and detecting the mass of the ammonia in real time;

[0008] An interaction and total nitrogen calculation module in signal connection with the above three modules for receiving the ammonia mass data and automatically calculating and outputting the total nitrogen result of the urine in combination with the 24-hour urine volume;

[0009] The collection module, the sampling module, the conversion and measurement module are sequentially connected in the order of urine flow, the interaction and total nitrogen calculation module controls across the modules and synchronizes data to form a closed loop automatic detection path.

[0010] The present application has the following beneficial effects:

[0011] The traditional urine total nitrogen detection method usually includes multiple links such as manual sampling, chemical digestion, distillation and titration, which is not only complex and time-consuming, but also requires high professional skills of the operator and is easily disturbed by human error, resulting in poor detection efficiency and repeatability. Therefore, the present application constructs a full-process automatic system, which effectively simplifies the operation process, reduces or even eliminates the risk of sample pollution in the manual operation process, and improves the detection efficiency and accuracy.

[0012] ICU, postoperative recovery or critically ill patients usually collect urine through urine bag, which is high in labor cost and cannot be continuously collected. Therefore, the present application designs a closed collection device compatible with the urinary catheterization system to improve the collection efficiency and reduce the nursing burden.

[0013] The distillation-titration detection method of the traditional Kjeldahl method is complicated in operation steps, and the measurement result is affected by factors such as operation condition and titration end point judgment. The present application uses an ammonia sensor under sealed conditions to analyze the ammonia concentration and quickly calculate the ammonia mass, which significantly improves the detection accuracy and speed, reduces the subjective factor interference in the measurement process, and is more suitable for the needs of clinical evaluation.

[0014] The traditional urine total nitrogen detection method is difficult to grasp the nitrogen excretion rhythm of the patient, and the detection process depends on the experience of personnel, and the time is unstable. The present application sets the detection time and detection period through programming of the system control unit, without manual intervention, and can realize automatic timed sampling analysis of the total nitrogen of urine.

[0015] The application provides a full-automatic and intelligent device for realizing urine total nitrogen detection.

[0016] The application provides a closed urine collection method for bedridden patients, which is directly connected with a urinary catheter, does not need to frequently replace containers or manual intervention, and is especially suitable for bedridden patients with limited activities in ICU, postoperative recovery and other scenes, and improves the convenience and safety of sampling.

[0017] The application provides a non-titration detection method based on an ammonia gas sensor, which discards the distillation-titration detection method of the traditional Kjeldahl method, uses the ammonia gas sensor for concentration analysis, improves the detection sensitivity and automation degree, cooperates with a known volume to quickly calculate the ammonia gas quality, is more convenient to operate, and is more stable in results, and is not affected by operation conditions, titration end point judgment and other factors to affect the measurement accuracy, and is suitable for bedside detection needs.

[0018] The application provides a timing automatic detection method, supports a timing automatic detection function, sets a sampling and detection cycle through a system control unit, and can automatically sample and analyze urine total nitrogen within a specified time without manual intervention. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a 24-hour urine total nitrogen automatic measurement device structure diagram of the application.

[0020] Figure 2 It is a 24-hour urine total nitrogen automatic measurement device module schematic diagram.

[0021] Figure 3 It is a 24-hour urine total nitrogen content automatic measurement method flow chart. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the application clearer, the application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the application and do not limit the application. In addition, the technical features involved in each embodiment of the application described below can be combined with each other as long as they do not conflict with each other. In order to achieve the above purpose, the application adopts the following technical scheme.

[0023] As shown in Figure 1 and Figure 2 , it is a 24-hour urine total nitrogen automatic measurement system of the application, and the measurement method of the system is as shown in Figure 3The system includes four core modules: automatic urine collection module, automatic sampling module, nitrogen-containing organic matter conversion and ammonia measurement module, and interactive and total nitrogen calculation module.

[0024] The automatic urine collection module includes a urinary catheter 1, a urine collection cabin 2, a disposable collection bag 3, and an oscillator 4. The urinary catheter 1 is connected to the urine collection cabin 2 to establish a closed-loop urine collection path, realizing continuous and real-time collection of urine. The urine collection cabin 2 is internally pre-installed with a flexible disposable collection bag 3 made of medical-grade PE, which has good chemical stability, acid and alkali resistance, and flexibility. The oscillator 4 using a piezoelectric ceramic sheet is used on the outer wall of the reaction cabin to fully mix and homogenize the urine in the reaction cabin before sampling. A weighing unit is arranged below the urine collection cabin 2 to calculate the mass of the collected urine, and the volume of the urine can be calculated according to the density of the urine. At the same time, to adapt to the non-fixed state of the patient moving and examination, the end of the urinary catheter 1 is designed with a switchable interface, which can be quickly switched to a traditional urine bag without disturbing the patient, ensuring the practicability and flexibility of the system in multiple clinical scenarios.

[0025] The automatic sampling module includes a sampling pump 5 and a liquid level sensor 6. The sampling pump 5 adopts a peristaltic pump structure, which is connected to the liquid pipeline between the urine collection cabin 2 and the reaction cabin 8, and can continuously, slowly and uniformly pump the urine from the collection cabin 2 to the subsequent module. The peristaltic pump can prevent backflow, bubble residue and cross contamination, and improve the purity of the sample. The urine is pumped by the sampling pump 5 and delivered to the reaction cabin 8. To realize automatic monitoring and control of the sampling volume, a high-sensitivity liquid level sensor 6 is arranged inside the reaction cabin 8. Once the urine rises to the set liquid level (i.e. the 100mL mark), the liquid level sensor 6 generates a liquid surface reaching signal and transmits the signal to the control unit 13, automatically closing the sampling pump 5 to ensure accurate and consistent sampling volume.

[0026] The nitrogen-containing organic matter conversion and ammonia measurement module includes an electric heating assembly 7, a reaction chamber 8, a gas pressure and temperature sensor 9, a reaction reagent tube 10, an ammonia sensor 11, and a gas pressure valve 12. In order to convert various nitrogen-containing organic matters in urine into a measurable form, a heating assembly and multiple reaction reagent tubes are integrated in the reaction chamber. The reaction chamber 8 is made of Hastelloy alloy which has excellent high-temperature resistance, high-pressure resistance and corrosion resistance. The reaction reagent tube 10 is sequentially opened to inject concentrated sulfuric acid and catalyst (copper sulfate). The opening and closing of the reaction reagent tube 10 are precisely controlled by the reaction program preset in the control unit 13. During the reaction process, the control unit 13 raises the temperature gradient to the target 400°C and maintains it for 30 minutes. During this period, the nitrogen source substances such as proteins, urea and creatinine in the urine are completely oxidized to generate stable ammonium bisulfate salt (NH4HSO4). There is a temperature and gas pressure sensor 9 in the reaction chamber 8. When the temperature is cooled to sixty degrees, the gas pressure valve 12 is opened to release the gas pressure to one standard atmosphere. The reaction reagent tube 10 is automatically opened to inject sodium hydroxide solution to neutralize the acidity of the reaction system and quickly build a strong alkaline environment. The control unit 13 maintains the temperature at 60°C. NH4 + will be converted to gaseous NH3. The entire reaction process is completed in a closed reaction chamber 8, ensuring that ammonia is effectively released and not leaked, providing good stability and reproducibility for gas detection. A high-sensitivity ammonia sensor 11 is installed at the top of the reaction chamber 8. The ammonia sensor 11 uses an electrochemical structure and has high selectivity to respond to NH3 molecules. After receiving the change in ammonia concentration in the cavity, the ammonia sensor 11 outputs an electric current signal to the control unit 13, which can be converted to the mass concentration of ammonia through a calibrated curve to monitor the released ammonia concentration in real time. Combined with the known volume and temperature and humidity control of the cavity, the mass content of NH3 in the gas is calculated through a calibration formula. Finally, the control unit 13 opens the reaction reagent tube 10 to inject boric acid to absorb the toxic NH3 gas in the reaction chamber. The ammonia sensor 11 has fast response time and strong selectivity, and is suitable for quantitative analysis of trace ammonia in complex clinical backgrounds, replacing the traditional distillation and titration process, and improving the intelligent degree and response speed of detection.

[0027] The interaction and total nitrogen calculation module includes a control unit 13. After the urine sample is subjected to acid high-temperature digestion and subsequent alkalization treatment, all organic or inorganic nitrogen sources (proteins, urea, creatinine, etc.) are finally converted into ammonia. Since each ammonia molecule (NH3) contains one nitrogen atom with a molar mass of 17 g / mol, and the nitrogen element accounts for 14 g / mol, it can be considered that the mass of the detected NH3 represents the amount of total nitrogen in the urine sample (multiplying the proportion coefficient of 14 / 17 can obtain the pure mass of nitrogen element). The amount of total nitrogen detected in the urine sample is calculated with the total urine volume collected in 24 hours to obtain the 24-hour urine total nitrogen, and the calculation formula is as follows:

[0028] ;

[0029] wherein, is the measured mass concentration of ammonia gas, is the volume of the reaction chamber, is the volume of the urine sample, is the density of the urine, is the weight of the collected 24-hour urine.

[0030] The final result can be displayed on the terminal interface and uploaded to the hospital information system through the network interface to realize real-time sharing, archiving and clinical decision assistance of urine total nitrogen data.

[0031] The device forms a complete closed-loop detection process between each module, realizing fully automated processing of urine total nitrogen from collection to result output. The device has high detection sensitivity, convenient operation and clinical practicability, and is suitable for clinical departments such as ICU, geriatric department, postoperative rehabilitation, etc. which have high demand for dynamic monitoring of urine nitrogen, and has good application prospect.

Claims

1. An apparatus for automatic measurement of 24-hour total urinary nitrogen, characterized by comprising: The application relates to a urine automatic collection module for continuously guiding patient urine into a disposable collection bag in a closed loop path and homogenizing and weighing the urine in the bag; an automatic sampling module in liquid connection with the urine automatic collection module for extracting the homogenized urine in a peristaltic mode and injecting a fixed volume of sample into a reaction cabin; a nitrogen-containing organic matter conversion and ammonia gas measurement module connected to the downstream of the automatic sampling module in a sealed mode for converting all nitrogen sources in the sample into ammonia gas and real-time detecting the mass concentration of the ammonia gas; and an interaction and total nitrogen calculation module in signal connection with the three modules for receiving the ammonia gas mass concentration data and automatically calculating and outputting urine total nitrogen results in combination with 24-hour urine volume. The collection module, the sampling module, the conversion and measurement module are sequentially connected in the order of urine flow, the interaction and total nitrogen calculation module controls across the modules and synchronizes data to form a closed loop automatic detection channel. The urine automatic collection module comprises a catheter with a detachable interface at the outlet end and a sealable connection with a patient catheterization system at the inlet end; a urine collection cabin with a disposable medical PE collection bag and a piezoelectric ceramic oscillator outside the cabin wall; and a weighing unit installed below the collection cabin for real-time acquisition of the urine mass in the bag and conversion of the volume. The automatic sampling module comprises a peristaltic sampling pump with the inlet end connected to the bottom of the collection cabin and the outlet end connected to the top of the reaction cabin to ensure one-way bubble-free transportation; and a liquid level sensor at a set height in the reaction cabin for sending a pump stop signal to the interaction module when the sample volume reaches a threshold. The nitrogen-containing organic matter conversion and ammonia gas measurement module comprises a hastelloy reaction cabin with an integrated electric heating assembly, a temperature sensor and a gas pressure sensor on the top cover; a plurality of reaction reagent tubes for controlled injection of concentrated sulfuric acid, a catalyst, sodium hydroxide and boric acid into the cabin in sequence; an ammonia gas sensor of an electrochemical type installed on the cabin top and in communication with the gas phase space in the cabin; and a gas pressure valve for balancing the pressure inside and outside the cabin after temperature rising and digestion and emptying residual gas after detection. The electric heating assembly can be heated to 400 DEG C and kept for 30 min under the instruction of a control unit and then cooled to 60 DEG C to complete nitrogen source conversion and ammonia gas release.

2. The apparatus of claim 1, wherein, The interaction and total nitrogen calculation module calculates the 24-hour urine total nitrogen by taking the amount of total nitrogen in the urine sample and the total urine volume collected in 24 hours as calculation parameters according to the following formula: Total nitrogen = (ammonia gas mass concentration) * (24-hour urine volume) / 1.

25. The catheter end is provided with a switchable interface for quick switching of a traditional urine bag without interrupting the closed loop collection. The disposable collection bag and the urine collection cabin are in a flexible nested structure, allowing the oscillator to indirectly homogenize the urine in the bag through the cabin wall without directly contacting the sample. The liquid level sensor is a high-sensitivity capacitive probe, and the signal cable is directly connected to the control unit to realize zero-delay pump stopping.

3. The apparatus of claim 1, wherein, The current signal output by the ammonia gas sensor is converted into ammonia gas mass in real time through a built-in calibration curve in the control unit, and a boric acid absorption program is triggered after the detection is completed to neutralize residual ammonia gas. ​ ​ ​ 4. The apparatus of claim 1, wherein, ​ ​ ​ ​ ​ ​ 5. The apparatus of claim 4, wherein, ​ ​ 6. The apparatus of claim 1, wherein, ​ ​ ； wherein, is the measured mass concentration of ammonia gas, is the volume of the reaction chamber, is the volume of the urine sample, is the density of the urine, is the weight of the collected 24-hour urine.

7. The apparatus of claim 1, wherein, ​ ​ 8. The apparatus of claim 1, wherein, ​ ​ 9. The apparatus of claim 3, wherein, ​ ​ 10. The apparatus of claim 4, wherein, ​ ​

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