PHYSIOLOGICAL FLUID COLLECTION BAG WITH INSTANT DATA TRANSMISSION

20200163608 ยท 2020-05-28

Assignee

Inventors

Cpc classification

International classification

Abstract

The design and structure of a physiological fluid collection bag with instant data transmission utilizing micromachined thermal time-of-flight flow sensing device as well as integrated pH value and density sensors for simultaneous and continuous measurement of the instant volumetric flow rate, accumulated total volume, pH value and density or specific gravity data of the collected fluid is disclosed in embodiments. The fluid collection bag includes a collection chamber and storage chamber wherein the sensing and measurement module is installed inside the storage chamber of the bag, for which it can be fully disposable. The fluid collection bag is able to metering the flow rate and instantly relay the data to the reusable data processing unit that can transmit the data to the designated data center or to the specified medical staffs.

Claims

1. A digital physiologic fluid collection bag with instant data transmission having the capability to instantly and continuously metering the discharged fluid volume as well as pH value and density or specific gravity of collected fluids; the digital physiological fluid collection bag includes two constituents, one is fluid collection, sensing and measurement unit which is fully disposable while another unit is for data processing and data transmission which is a reusable unit; the two units are connected with an electrical shielded cable, the digital physiological fluid collection bag comprising A disposable fluid collection bag having two separate chambers wherein an upper chamber is used for fluid collection and a lower chamber for fluid storage; A V shaped structure configured and separated the two chambers wherein a channel for fluid passage is disposed at very bottom of the V shaped structure; A fluid measurement assembly wherein guided fluid channel diameter at fluid entrance is gradually reduced towards the measurement sensing channel, wherein the fluid measurement assembly is completely biomedical compatible to avoid any inaccuracy in measurements; A fluid sensing and measurement module having at least three sensing elements inside a fluid sensing channel: a MEMS thermal time-of-flight sensor to metering volume of discharge fluid; a pH sensor measures pH value of the fluid and a density or specific gravity sensor measures density of the fluid; each of the sensors is connected to an enclosed and hermetically sealed PCB with individual calibrated data; A medical grade and electrically shielded cable for data relay to the data processing unit; A check valve connected to both the guided fluid travel tunnel and the fluid collection chamber to prevent collected fluid back filling to the patient, and a manual release valve at bottom of the storage chamber for sample extraction; and A data processing, analyzing and transmission unit which is used to process measured data from the sensing and measurement module and to wirelessly transmit the data to a specific data center or medical staffs; in case in an environment wherein wireless data are not allowed, a wired option is also available via the standard Ethernet cable network.

2. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the V shaped fluid collection chamber is configured and separated from medical or biocompatible materials wherein a fluid release channel is available at the lowest point of the V shape structure; the angles for the V is from 70 to 140, but preferably 100 to 130, and most preferably 110 for the best fluid collection without creating a non-filled channels as well as to prevent excessive air bubbles entering into the measurement channel.

3. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein sensing and measurement module have a guide channel connected directly to a fluid release channel of the fluid collection chamber; the guided channel have a gradually reduced channel diameter size for additional insurance of a completely filled channel while the air entrance into the channel could also be blocked with the filled fluid wherein reduction of the channel diameter size from the largest to the smallest shall be from 2:1 to 5:1 depending on the fluid discharge total volume or the fluid collection bag size, but preferably the ratio shall be 3:1 to 4:1 and most preferably to be 3.5:1.

4. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the sensing and measurement module have at least three sensors to provide basic and instant medical data of the fluid; a flow sensor is used to metering instant volume and register total volume of each discharge; the flow sensor is preferred to be made by micromachining or a MEMS process that provides the thermal time-of-flight metrology capability; such a sensor is more accurate compared to the conventional mass flow sensing elements wherein the accuracy is greatly alternated due to variations of the fluid properties; for best interests of fluid properties, the flow sensor has capability of a large dynamic range over 100:1 and with a full scale capability not smaller than 200 mL/min; it is preferred that the flow sensor takes the data no longer than every one minute, and preferably every 10 seconds, and most preferably every 5 seconds.

5. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the sensing and measurement module have a chemical sensor that can measure the pH value of the fluid. For the limited spacing, it is preferred that such a pH sensor also is micromachined on a glass substrate for the ultimate compatibility and resistance to any corrosive possibility by collected fluid; the pH sensor is able to measure the pH value from 4.0 to 8.0, and preferably having an accuracy better than 0.5%; the pH sensor is able to continuously measure the incoming discharged fluid and take data no longer than every one minute, and preferably every 10 seconds, and most preferably every 5 seconds.

6. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the sensing and measurement module have a density or specific gravity sensor that is miniaturized using a micromachined process; it is critical that the density sensor has a high resolution with a capability to capture any changes of density in 1000 ppm or less, and preferably in 100 ppm; the density sensor is able to continuously measure the incoming discharged fluid and take data no longer than every one minute, and preferably every 10 seconds, and most preferably every 5 seconds.

7. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the sensing and measurement module have an EPPROM to store calibration data for each of the sensors; the EPPROM is installed on a hermetically sealed PCB and connected to the sensors such that the whole unit can be disposed after the usage; the PCB have a medical grade and hermetically sealed connector through which a medical grade and electrically shielded cable can be connected and relay the acquired data to the data processing unit.

8. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the fluid release channel after the measurement channel have a varied channel diameter, wherein a from channel end with smallest diameter is connected to the measurement channel while a rear channel end with largest channel diameter is connected to a buffer unit which is used to further enhance stable flow and ensure a fully filled measurement channel; the buffer unit is directed to a fluid release unit to the fluid storage collection chamber.

9. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the check valve is installed at the fluid entrance to the fluid collection chamber to prevent the back filling of the collected fluid from the bag to the patient; another manual valve is placed at the very bottom of the storage chamber such that the fluid sample can be accessed whenever there is a need for further laboratory analysis of the collected fluid.

10. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein the data processing unit have a display to instantly exhibit the data locally; a keyboard is included on the data processing unit such that parameters such as user information, alarm setting and data collection time frame can be programmed locally; the data processing unit have a capability to transmit. the measured data either via network cable or wirelessly and instantly to the designated medical center or to specific medical staffs; for user friendly purpose, several data transmission approaches such as low energy Bluetooth, NB-IoT and LoRa are also available; for best interests of medical applications, the parameters or the settings are able to be programmed remotely.

11. The digital physiological fluid collection bag with instant data transmission of claim 1 wherein both the fluid collecting and measurement unit as well as the data processing unit is fully compatible with medical device regulations.

Description

BRIEF DESCRIPTIONS OF THE DRAWINGS

[0015] FIG. 1 is the digital physiological fluid collection bag assembly showing the bag configuration with a fluid collection chamber and a fluid retaining chamber where the measurement unit is installed. The bag shall be fully disposable while the control electronics that is connected to the bag via a medical grade cable. The control electronics shall process the measured data and then instantly transmit such data to the designated data center that can be reached by the doctor or medical staff.

[0016] FIG. 2 is a detailed view of the configuration of the two chambers inside the digital physiological fluid collection bag where the upper chamber is used for collect the fluid such that the discontinuation of the discharge can be eliminated while the lower chamber is used for the detainment of all discharged fluid.

[0017] FIG. 3 is the detailed disclosure of the measurement unit with the flow stabilizing channel. The chamber is embedded with three sensing elements for fluid volume, pH values and densities.

[0018] FIG. 4 is the cross section revealing the arrangement of the three sensing elements and one calibration data storage unit with the interface for connection to the control electronics.

[0019] FIG. 5 is the schematic for a check valve.

[0020] FIG. 6 is the schematic for a sample valve.

[0021] FIG. 7 is the block diagram of the control electronic unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] For the preferred embodiment, the present disclosure of a new digital physiological fluid collection bag that utilizes the micro-machined integrated thermal time-of-flight flow sensor for instant volume and pH sensor and density sensor for instant fluid analysis is show in FIG. 1. The new concept for a physiological fluid collection has two crucial improvements over the current visual data assessment from a plastic bag. On the one hand, the capability of instant and digital data streaming for the high precision measurement of the actual discharged fluid volume enables the knowledge of the patient's instant and continuous status under medication which is not possible with the current technology. The constant feedback of the patient's status enables the medical doctor to precisely make decisions on the care plan for the particular patient that not only significantly boosts the recovery but also may save significant medical resources. In the example of urine collection, the patient's glomerular filtration rate, electrolyte balance, and acute renal failure could all be instantly become available to the medical doctor. On the other hand, the addition of the fluid analytical sensors such as pH sensor and density sensor that are disclosed in the present invention also allows the data to often be obtained by sampling and laboratory time at future. This addition also allows the patient's physical status to be plotted in real time that could be crucial in particular for patient having kidney related diseases. It is also easily extended to the additional variety of the fluid collection bags with other new chemical and or physical data analysis sensors, which should be a desirable function. The present concept and design therefore discloses a new physiological fluid collection bag that can use the micro-machined physical and chemical sensors to instantly measure the desired data of the fluid and instantly transmit such data to the medical doctor or staff, which can significantly help the recovery of the patient with more precise knowledge and feedbacks from the instant status of the patient through a much better, timely and appropriate care plan.

[0023] The digital physiological fluid collection bag shown in FIG. 1 shall be constituent with two main parts, the physiological fluid collecting and metrology unit 100 which has the physical bag made of medical grade plastics for collecting the fluid wherein the metrology data sensing module 200 measures and digitizes the physical volume of the collected fluid. This pan shall be fully disposable or for one-time usage only, and it shall be preferably connected via a shield cable 510 to the data analysis. And processing unit 300 shall have the functionality for data processing, analysis, as well as for further data transmission.

[0024] For the preferred embodiment, the digital physiological fluid collection bag will have two chambers as shown in FIG. 2. The upper chamber 120 shall be used for guiding the physiological fluid into the fluid release channel 125 that have the metrology data sensing module 200 being placed. For accurate measurement with a fluid flow sensor, it is critical to have the channel completely filled with fluid to be measured. Therefore the channel entrance shall be at the very bottom of the V shaped chamber 120 with which the fluid collected shall be populated. The second chamber 130 shall then be used for the fluid storage after the fluid is metered. In order to prevent the fluids from filling back to the patient, at the entrance 115 on the bag for the incoming fluid, a check valve 420 is installed such that no fluid after entering into the bag shall be able to escape. From time to time, it is desired to have the collected fluid to be further analyzed by a medical laboratory. To this purpose, a manual valve 450 shall be placed at the bottom of the bag, with which the sample of the fluid shall be easily accessed with an external utensil or a medical fluidic sample holder. Another feature for the physiological fluid collection bag is a fixture 110 that shall be applied to a hook or similar structure such that the collection bag will be kept in a relatively still status, which shall also be helpful for the performance of the metrology module.

[0025] FIG. 3 exhibits the detailed structure and configuration of the metrology data sensing module 200. This module shall be the key component of the digital physiological fluid collection bag. The fluid entrance collector 210 is a short connection fluidic channel with its channel size reduced towards the entrance of the metrology unit 220. On the top of the fluid entrance collector 210, a click fasten ring 215 is used to connect with tight seal to the fluid collection chamber 120 of the fluidic collection bag. This configuration of the collector 210 with a reduced fluidic flow channel shall forces the incoming fluid running with a reduced flow rate that shall also help the reduction of bubbles inside the fluid wherein a filled channel would be better ensured. The ratio of the entrance channel size to that for the connection with the metrology unit in the preferred embodiment shall be 2:1 to 5:1 depending on the fluidic collection bag size. A bubble filter could also be installed at the entrance 215 assisting the clearance of the possible bubbles which shall be detrimental for an accurate measurement of the fluidic volume. The exit channel 230 has a similar shape as the fluid entrance collector 210 but with a larger channel size section placed towards the fluid exit direction such that it shall have a faster release to the fluid storage chamber 130. The buffer container 240 shall be used for assisting the removal of bubbles as well as for reducing the traveling speed of the fluid such that the accuracy of the measurement can be ensured. In a preferred embodiment, a pressure sensor can also be placed at the bottom towards the exit of the fluid from the measurement channel and the sensor can be used for additional information of the fluid volume passing through the channel. The unit 250 after the buffer 240 is used for guiding the fluid into the storage chamber 130, and finally the complete module shall be connected preferably by a medical grade connector 520 via an electrically shielded cable 510 to the data process unit 300

[0026] The detailed illustration of the metrology data sensing module 200 can be found in FIG. 4 which is a cross-section of the main portion of that shown in FIG. 3. The fluid flow channel 212 has a diameter gradually reduced from fluid entrance, and before reaching to the metrology channel wherein three sensors are installed: 222 is a pH sensor that in the preferred embodiment is made via a micromachined process or a MEMS process, and this sensor shall metering the pH value of the collected fluid; 224 is preferred to be a MEMS thermal time-of-flight flow sensor that can metering the volume of the collected fluid; and 226 is a density sensor that shall be in the preferred embodiment also made with a micromachined or MEMS process. The sensors are connected directly to a printed circuitry board (PCB), 225 on which the connector 228 shall be connected externally to the medical grade connector 520. The construction materials of the module shall be completed with medical grade plastics in which the chambers of the sensing unit 220 shall be hermetically sealed and shall be water or fluid proof including the interface of the connector 228. In a preferred embodiment, and for the purpose of disposability, the electronics on the PCB shall be limited to have only an EPPROM in which the calibration data for each of three sensors shall be stored, as even with a fully automatic assembly process, there would be some minor deviations for each of the installed MEMS sensors, and the data in the EPPROM will eliminate such deviations via the calibration of each of the three sensors. Such deviations include, for example, the offset, full scale, and the output linearity.

[0027] For the preferred embodiments, the pH sensor shall provide continuously measurement for the pH values of the collected fluid. For the concerns of a human fluid, such as urine, the pH sensor shall only need to cover a relatively narrow range but a high resolution and accuracy shall be required. The preferred pH values to be measured shall be close to 6.2 with a span no more than 2.5. As the abnormal pH value of urine, for example, could be an indication of certain diseases such as acidosis or dehydration for low pH values or urinary tract obstruction or salicylate intoxication for high pH values. As the accurate measurement of the pH values often requires a fresh sample, the in situ continuous measurement by the embedded pH sensor would provide the most valuable pH data for the patient, which often could not be performed by the current practice because the sampling time is often depending on the schedule of the medical staff on shift and the availability of nearest laboratory. Also the continuous pH data plot shall reflect any medical condition improvement of the patient with time, which is also not be possible with the current technologies.

[0028] For the preferred embodiment, the MEMS thermal time-of-flight (TTOF) flow sensor shall provide continuous metering on the volume of the discharge fluids, and shall record the start and stop for each discharge. In the current practice, for example, for urine discharge, the urine collected by the urine bag cannot record any information of amount, timing and actual flow information as for the collected urine. The urine may be from one time or may be from multiple time discharges at the time the medical staff inspects the physical urine bag. In this particular example, the urine flow shall be an indication of renal perfusion, or an indication of Glomerular Filtration Rate (GFR), changes in extracellular fluid and kidney function. In an intensive Care Unit (ICU), the infused fluids to a patient is well documented, but the precise discharge information from the patient is missing, and hence some parameters such as instant changes in patient's electrolyte balance could not be made available. With the in situ TTOF flow sensor, not only the discharged fluid can be precisely measured by the volume but exactly by the volume of each discharge. In addition, the TTOF flow sensor shall also be able to instantly measure the flow rate of the discharged fluid. Such a flow rate would be a direct indication of GFR with which the possibility of a chronic renal failure or acute renal failure shall be captured instantly and timely. Hence, for this reason, the TTOF flow sensor shall be able to cover the flow range from low 100 mL/min to 200 mL/min or the average flow rate can be deducted from the volume and time of each complete discharge that is real time metered.

[0029] For the preferred embodiment, tire micromachined density sensor shall register the changes of tire discharge fluid in an instant and timely manner. The density or specific gravity that is associated to the osmolarity is a directly indication of wire impurities inside the discharged urine. A higher specific gravity than that of a normal value (1.003 to 1.035) is often a direct indication of urinary tract infection or some malfunction of kidney. The continuous data made available shall be very valuable in particular for monitoring the patient in recovering from a kidney disease or other related disease. Any abrupt changes with the instant data shall be able to provide direct warnings to the medical staff, and therefore an instant remedy could be timely applied.

[0030] For the preferred embodiment, the check valve 420 (FIG. 5) shall have a v-nozzle 421 to the guided tube for connecting the patient while another v-nozzle 423 to direct the fluid into the fluid collection chamber 120. The valve shall be placed inside the enclosure 422 that will prevent the fluid back filled from the fluid collecting chamber 120 to the patient via the guided tube FIG. 6 is an illustration of the manual value 450 installed at the bottom of the digital physiological fluid collection bag. The tube 452 is connected to the fluid storage chamber of the bag while the pipe 455 shall direct the fluid to the sample utensil or sample container when the manual valve 453 is switched to open position.

[0031] For the preferred embodiment, the data processing unit 300 shall have a display 350 such as a liquid crystal display (LCD) or light emitting-diode (LED) or organic light emitting-diode (OLED). A keyboard 360 shall be used to program the data processing information or enter parameters or information of the patient. Inside the front cover 330, there are control electronics containing analog to digital converter, a microprocessor for data process, and data storage unit. It shall further contain the wireless data transmission unit such as low energy Bluetooth, NB-IoT module or LoRa module. In case that the wireless data transmission is not preferred, wired data transmission via a local network using interfaces such as 10-Link or standard RS485 Modbus would be available. The data can be transmitted to a central station assigned by the medical staff or directly to the smart devices owed by the specific medical staffs.

[0032] For the additional preferred embodiment, the digital physiological fluid collection bag for those in the art could be further incorporated with additional features such as a color recognition sensor and other chemical sensors, and the data shall be available for use for full spectrum medical data analysis. It is readily and apparently that the applicable fluid shall preferably be urine but shall also be applicable to general purpose physiological fluid collections.