SYSTEM FOR AUTOMATED MEASUREMENT OF FLUID OUTPUT
20170307423 · 2017-10-26
Inventors
Cpc classification
A61B5/208
HUMAN NECESSITIES
G01F23/20
PHYSICS
G01F1/007
PHYSICS
International classification
Abstract
A system for automatically measuring and recording when fluid such as urine is introduced to a fluid collection container is provided. The system includes a measuring device that includes a load cell in communication with other various electronic components. The load cell is attached on one end to a fixed object like a hospital bed. At its other end, it is attached to a fluid collection container such as a urine collection bag. When fluid is introduced into the container, the load cell detects a stress change. A strain gauge (or gauges) on the load cell detects a resistance change and reads the change as a voltage change. That voltage change is amplified and digitized and converted to a weight, volume, and flow rate, before being transmitted to a recordkeeping system like electronic medical records. The system thus provides for real time measurement of fluid output collected in the container.
Claims
1. A system for automated measurement of fluid output, the system comprising: a measurement device, the measurement device comprising: a load cell; at least one strain gauge positioned and located on the load cell; a first attachment member at an upper portion of the load cell for attaching the upper portion of the load cell to a fixed point; a second attachment member at a lower portion of the load cell for attaching the lower portion of the load cell to a fluid collection container; and a microprocessor in communication with the at least one strain gauge that receives a voltage of the at least one strain gauge, wherein when fluid is added to the fluid collection container the voltage across the at least one strain gauge changes, and the microprocessor calculates at least one of a volume and a flow rate of fluid added to the fluid collection container.
2. The system of claim 1, wherein the load cell is an S-type load cell.
3. The system of claim 1, wherein the system includes four strain gauges arranged as a Wheatstone bridge.
4. The system of claim 1, wherein the system includes an amplifier that amplifies the voltage of the at least one strain gauge before the voltage is received by the microprocessor.
5. The system of claim 1, wherein the system includes an electronic database to which the at least one of a volume and a flow rate is output.
6. The system of claim 5, wherein the electronic database is an electronic medical record hosted on at least one of a computer device and a cloud storage.
7. The system of claim 1, wherein the system includes an analog to digital converter that converts the voltage received from the load cell to a digital signal.
8. The system of claim 1, wherein the system includes a housing in which the load cell is contained.
9. A system for automated measurement of fluid output, the system comprising: a fluid collection container; a measurement device, the measurement device comprising: a load cell; at least one strain gauge positioned and located on the load cell; a first attachment member at an upper portion of the load cell for attaching the upper portion of the load cell to a fixed point; a second attachment member at a lower portion of the load cell for attaching the lower portion of the load cell to the fluid collection container; and a microprocessor in communication with the at least one strain gauge that receives a voltage of the at least one strain gauge, wherein when fluid is added to the fluid collection container the voltage across the at least one strain gauge changes, and the microprocessor calculates at least one of a volume and a flow rate of fluid added to the fluid collection container.
10. The system of claim 9, wherein the load cell is an S-type load cell.
11. The system of claim 9, wherein the system includes four strain gauges arranged as a Wheatstone bridge.
12. The system of claim 9, wherein the system includes an amplifier that amplifies the voltage of the at least one strain gauge before the voltage is received by the microprocessor.
13. The system of claim 9, wherein the system includes an electronic database to which the at least one of a volume and a flow rate is output.
14. The system of claim 13, wherein the electronic database is an electronic medical record hosted on at least one of a computer device and a cloud storage.
15. The system of claim 9, wherein the system includes an analog to digital converter that converts the voltage received from the load cell to a digital signal.
16. The system of claim 9, wherein the system includes a housing in which the load cell is contained.
17. A method for measuring urine output in real time, the method comprising the steps of: sensing a load change as a voltage change in a load cell that is attached at an upper end to a fixed point and at a lower end to a fluid collection container when fluid is added to the fluid collection container; outputting the voltage change from the load cell to a microprocessor; converting the voltage change to a weight change; converting the weight change to at least one of a volume and a flow rate; and outputting the at least one of a volume and a flow rate to an electronic medical record hosted on at least one of a computer device and a cloud storage.
18. The method of claim 17, wherein the voltage change is amplified before it is output to the microprocessor.
19. The method of claim 18, wherein the voltage change is digitized by an analog to digital converter before it is converted to a weight change.
20. The method claim 18, wherein the system includes four strain gauges arranged as a Wheatstone bridge.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0012]
[0013]
[0014]
[0015]
[0016]
DETAILED DESCRIPTION OF THE INVENTION
[0017] Referring to the drawings more particularly by reference numbers wherein like numbers refer to like parts,
[0018] A fluid collection container 40 is preferably in fluid communication with a patient's bladder or other fluid producing organ or body part. For example, the fluid collection container 25 may be a urine collection bag (as illustrated) having a tube (not illustrated) that is in fluid communication with a catheter placed in a patient's bladder (not illustrated, but well understood in the art). As shown in
[0019] Turning now to
[0020] A strain gauge 70 is shown and illustrated near a center, hollow portion 75 of the load cell 55. The strain gauge 70 may be of the type commonly known and understood in the art that used to measure strain on an object (in this case the load cell 55). The strain gauge 70 preferably consists of an insulating flexible backing which supports a metallic deformable foil pattern. The strain gauge 70 may be attached to the load cell 55 by a suitable adhesive, such as a cyanoacryoate. When the foil of the load cell 55 is deformed, the electric resistance of the strain gauge 70 changes. The load cell 55 may include up to four strain gauges such as strain gauge 70. Preferably, the strain gauges 70 are arranged as a Wheatstone bridge, an electric circuit configuration commonly in the electrical arts used to measure resistance.
[0021] As described above, the center of the load cell 55 may be hollow. This design helps to ensure that a linear output voltage from the load cell 55 is produced as a function of weight.
[0022] As set forth above, the load cell 55 is preferably in communication at its upper and lower ends 60, 65 with the attachment members 15, 20, respectively. Thus, when the upper attachment member 15 is in communication with a hook member such as hook 30 (or other fixed point) and the lower attachment member 20 is coupled with a fluid collection container such as fluid collection container 40, a strain may be applied to the load cell 55 when a fluid is introduced to the liquid collection container 40. When this strain occurs, the strain gauge 70 (and any additional strain gauges present on the load cell 55) may detect a change in resistance.
[0023] The strain gauge or gauges 70 are preferably in electronic communication with various components of an electronic board 80, which may be embodied as a printed circuit board, or “PCB”. Various commonly known and understood electronic components are preferably mounted on the PCB 80. The illustrated embodiment provides a preferred embodiment, but other known or foreseeable electronic circuit configurations are also envisioned. In those embodiments, the electronic circuit would preferably carry out the methods described herein.
[0024] In a preferred embodiment, the illustrated PCB 80 includes each of an amplifier 85, an analog to digital converter 90, a microprocessor 95, a transmission unit 100, and a power source 105. As will be described below, the transmission unit 100 may be a variety of different transmission types including USB or Bluetooth. Similarly, the power source 105 may be a battery, supplied by USB power, or a separate communication such as AC power.
[0025] The load cell 55 and the PCB 80 are preferably contained within a housing 120. In at least one alternative embodiment described below, the load cell 55 and strain gauge or gauges 70 may be contained in one housing, while the printed circuit board is contained in a separate housing. In the illustrated embodiment however, the housing 120 that contains each of the load cell 55 (and strain gauge or gauges 70) and the PCB 80 includes each of a base member 125 and a lid member 130. The lid member 130 is preferably releasably attachable to the base member 125 in a known manner, like a friction fit.
[0026] The housing 120 may also include a port, or aperture, 135 located in the base member 125. The port 135 may be useful for the embodiment where the load cell 55 and strain gauge or gauges 70 are housed separately from the PCB 80 and where wires may be required to connect the load cell 55 and its strain gauge or strain gauges 70 to the PCB 80 in the manner described below.
[0027] Turning now to
[0028] A calibration factor 160 may be applied to the digitized output voltage 155 using a factor that is calculated to convert the change in voltage to a change in weight within the liquid collection container 40. A calculated weight 165 may then be subjected to software algorithms 170 that convert the weight calculation 165 to a volume and flow rate 175. The calibration factor 160 and software algorithms 170 may be carried out by the microprocessor 95 in a manner known and understood in the art, substantially similar to other microprocessors.
[0029] Data including the volume and flow rate 175 of fluid added to the container 40 may then be sent via the transmission unit 100 (which may be using USB or Bluetooth technology) to an electronic medical record 180 stored on a computing device, as known and understood in the art. That way, a medical professional may be able to retrieve data regarding fluid collecting in the fluid container 40 in real time by monitoring or reviewing the electronic medical record 180.
[0030] Turning now to
[0031] As previously set forth, the load cell is then preferably able send an output voltage to the amplifier 85 which amplifies the received voltage and sends the amplified voltage to the microprocessor 95. As mentioned above, the power source 105 may power not only the load cell 55 as shown in
[0032]
[0033] The substantial manner in which measurements are taken and data is output it is substantially similar to the process shown and illustrated in
[0034] In the embodiment described above, the housing 195 may be formed integrally with the container 40. In other embodiments, the housing 170 may also be integrally formed with the container 40.
[0035] Thus, there has been shown and described a system for continuous, automated measurement of fluid output, such as urine. As is evident from the foregoing description, certain aspects of the present inventions are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications, applications, variations, or equivalents thereof, will occur to those skilled in the art. Many such changes, modifications, variations and other uses and applications of the present constructions will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses in applications which do not depart from the spirit and scope of the present inventions are deemed to be covered by the inventions which are limited only by the claims which follow.