Patents by Inventor Louis LeeGrande Barrett

Louis LeeGrande Barrett has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20220323658
    Abstract: Embodiments of the disclosure provide a method for determining beginning blood volume of a patient during dialysis (e.g., hemodialysis). Ultrafiltration rates are determined at different time stamps during dialysis by obtaining a blood flowrate measurement and hematocrit measurements at input port and output port of a dialyzer connected to the patient. The flowrate and hematocrit measurements are used to determine fluid removed from the patient during dialysis. The ultrafiltration rates and fluid removed from the patient are used to determine the beginning blood volume of the patient.
    Type: Application
    Filed: June 17, 2022
    Publication date: October 13, 2022
    Inventors: Louis LeeGrande Barrett, Perry N. Law, Douglas L. Cox
  • Patent number: 11389576
    Abstract: Embodiments of the disclosure provide a method for determining beginning blood volume of a patient during dialysis (e.g., hemodialysis). Ultrafiltration rates are determined at different time stamps during dialysis by obtaining a blood flowrate measurement and hematocrit measurements at input port and output port of a dialyzer connected to the patient. The flowrate and hematocrit measurements are used to determine fluid removed from the patient during dialysis. The ultrafiltration rates and fluid removed from the patient are used to determine the beginning blood volume of the patient.
    Type: Grant
    Filed: December 3, 2018
    Date of Patent: July 19, 2022
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventors: Louis Leegrande Barrett, Perry N. Law, Douglas L. Cox
  • Publication number: 20220218888
    Abstract: A circuit for measuring the conductivity of a medical fluid, the circuit comprising: a data collecting cell through which a medical fluid is configured to flow; an input voltage source that provides an input voltage to the data collecting cell; a voltage measurement unit configured to measure the input voltage and an output voltage of the data collecting cell; and a switch in communication with the voltage measurement unit, the switch configured to switch between a first state in which the voltage measurement unit is configured to measure the input voltage and a second state in which the voltage measurement unit is configured to measure the output voltage of the data collecting cell.
    Type: Application
    Filed: December 8, 2021
    Publication date: July 14, 2022
    Inventors: Louis LeeGrande Barrett, Jon F. Moss, David W. Peterson, Ronald S. Glaittli
  • Publication number: 20220202316
    Abstract: A measurement system for measuring blood characteristics includes a controller, an emitter, a sensor, and a reference sensor. The emitter emits light at a plurality of wavelengths from a first side of a blood flow channel to a second side of the blood flow channel. The sensor is provided on the second side of the blood flow channel. The reference sensor is provided on the first side of the blood flow channel. The controller compensates measurements from the sensor based upon measurements from the reference sensor. The reference sensor may be disposed in a position to increase noise immunity of the measurement system. The measurement system may be connected to or part of a dialysis system.
    Type: Application
    Filed: January 19, 2022
    Publication date: June 30, 2022
    Inventor: Louis LeeGrande Barrett
  • Publication number: 20220104740
    Abstract: A hemodialysis patient data acquisition and management system resides on a host computer which receives information from one or more non-invasive, optical blood monitors associated with a hemodialysis system. When a patient is undergoing hemodialysis treatment, a sensor assembly monitors the patient's blood flowing through the hemodialysis system and a controller for the blood monitor generates data which includes at least an identification code for the patient undergoing the treatment on the respective system, and non-invasively determined blood data taken at the onset of the scheduled treatment, such as initial Hgb, HCT, and SAT values. A host computer communicates with the one or more optical blood monitors, preferably via a wireless network, and the patient's session commencement data is downloaded to the host computer.
    Type: Application
    Filed: December 17, 2021
    Publication date: April 7, 2022
    Inventors: Louis LeeGrande Barrett, David W. Peterson, Brian H. Nathanson, Michael J. Germain, Michael K. Black
  • Patent number: 11241176
    Abstract: A measurement system for measuring blood characteristics includes a controller, an emitter, a sensor, and a reference sensor. The emitter emits light at a plurality of wavelengths from a first side of a blood flow channel to a second side of the blood flow channel. The sensor is provided on the second side of the blood flow channel. The reference sensor is provided on the first side of the blood flow channel. The controller compensates measurements from the sensor based upon measurements from the reference sensor. The reference sensor may be disposed in a position to increase noise immunity of the measurement system. The measurement system may be connected to or part of a dialysis system.
    Type: Grant
    Filed: August 15, 2019
    Date of Patent: February 8, 2022
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventor: Louis LeeGrande Barrett
  • Patent number: 11141515
    Abstract: Embodiments of the disclosure provide a method for evaluating dialyzers used in different medical applications (e.g., hemodialysis). Red blood cell volume lost in a dialyzer is monitored by obtaining blood flowrate measurements and hematocrit measurements at input ports and output ports of the dialyzer. The flowrate and hematocrit measurements are used to determine an accumulation of red cell blood volume in the dialyzer. The measurements may be obtained in a lab environment with an in-vitro blood source or may be obtained in a clinical setting with an in-vivo blood source from a patient.
    Type: Grant
    Filed: July 30, 2020
    Date of Patent: October 12, 2021
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventors: Louis LeeGrande Barrett, Chih-Hu Ho, Eric Stroup
  • Patent number: 11013846
    Abstract: Systems and sensor clip assemblies for optically monitoring blood flowing through a blood chamber are provided. A sensor clip assembly includes emitters and photodetectors positioned on opposing arms, a signal conditioning circuit for conditioning raw analog signals generated by the photodetectors while the sensor clip assembly is fastened to a blood chamber, and an analog-to-digital converter for converting the conditioned analog signals to raw digital data. The sensor clip assembly may include a microcontroller for calculating parameters of blood flowing through the blood chamber such as hematocrit, oxygen saturation, and change in blood volume from the raw digital data. The sensor clip assembly is in communication with a networked computer, and the networked computer is in communication with a remote computer configured to provide a user interface for monitoring and/or controlling the sensor clip assembly.
    Type: Grant
    Filed: April 24, 2020
    Date of Patent: May 25, 2021
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventors: Louis LeeGrande Barrett, David W. Peterson, Matthew A. Stowell, Perry N. Law
  • Publication number: 20210077015
    Abstract: A method of performing closed-loop dialysis treatment during hemodialysis is provided. The method involves determining an initial ultrafiltration rate and setting an ultrafiltration pump of a dialysis system to the determined ultrafiltration rate. A series of measurements and calculations are made to ensure that a rate of change of blood volume during treatment follows a specified profile. A threshold may be used to keep the rate of change of blood volume tracking the profile. Patient fluid dynamics may be measured in real-time and used to determine the ultrafiltration pump rate.
    Type: Application
    Filed: November 30, 2020
    Publication date: March 18, 2021
    Inventors: Louis LeeGrande Barrett, Ken Chhi, David Yuds, Tom Merics, Joan Dowd
  • Publication number: 20200353150
    Abstract: Systems and sensor clip assemblies for optically monitoring blood flowing through a blood chamber are provided. A sensor clip assembly includes emitters and photodetectors positioned on opposing arms, a signal conditioning circuit for conditioning raw analog signals generated by the photodetectors while the sensor clip assembly is fastened to a blood chamber, and an analog-to-digital converter for converting the conditioned analog signals to raw digital data. The sensor clip assembly may include a microcontroller for calculating parameters of blood flowing through the blood chamber such as hematocrit, oxygen saturation, and change in blood volume from the raw digital data. The sensor clip assembly is in communication with a networked computer, and the networked computer is in communication with a remote computer configured to provide a user interface for monitoring and/or controlling the sensor clip assembly.
    Type: Application
    Filed: April 24, 2020
    Publication date: November 12, 2020
    Inventors: Louis LeeGrande Barrett, David W. Peterson, Matthew A. Stowell, Perry N. Law
  • Publication number: 20200353145
    Abstract: Embodiments of the disclosure provide a method for evaluating dialyzers used in different medical applications (e.g., hemodialysis). Red blood cell volume lost in a dialyzer is monitored by obtaining blood flowrate measurements and hematocrit measurements at input ports and output ports of the dialyzer. The flowrate and hematocrit measurements are used to determine an accumulation of red cell blood volume in the dialyzer. The measurements may be obtained in a lab environment with an in-vitro blood source or may be obtained in a clinical setting with an in-vivo blood source from a patient.
    Type: Application
    Filed: July 30, 2020
    Publication date: November 12, 2020
    Inventors: Louis LeeGrande Barrett, Chih-Hu Ho, Eric Stroup
  • Patent number: 10765792
    Abstract: Embodiments of the disclosure provide a method for evaluating dialyzers used in different medical applications (e.g., hemodialysis). Red blood cell volume lost in a dialyzer is monitored by obtaining blood flowrate measurements and hematocrit measurements at input ports and output ports of the dialyzer. The flowrate and hematocrit measurements are used to determine an accumulation of red cell blood volume in the dialyzer. The measurements may be obtained in a lab environment with an in-vitro blood source or may be obtained in a clinical setting with an in-vivo blood source from a patient.
    Type: Grant
    Filed: February 26, 2020
    Date of Patent: September 8, 2020
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventors: Louis LeeGrande Barrett, Chih-Hu Ho, Eric Stroup
  • Publication number: 20200188567
    Abstract: Embodiments of the disclosure provide a method for evaluating dialyzers used in different medical applications (e.g., hemodialysis). Red blood cell volume lost in a dialyzer is monitored by obtaining blood flowrate measurements and hematocrit measurements at input ports and output ports of the dialyzer. The flowrate and hematocrit measurements are used to determine an accumulation of red cell blood volume in the dialyzer. The measurements may be obtained in a lab environment with an in-vitro blood source or may be obtained in a clinical setting with an in-vivo blood source from a patient.
    Type: Application
    Filed: February 26, 2020
    Publication date: June 18, 2020
    Inventors: Louis LeeGrande Barrett, Chih-Hu Ho, Eric Stroup
  • Publication number: 20200171229
    Abstract: Embodiments of the disclosure provide a method for determining beginning blood volume of a patient during dialysis (e.g., hemodialysis). Ultrafiltration rates are determined at different time stamps during dialysis by obtaining a blood flowrate measurement and hematocrit measurements at input port and output port of a dialyzer connected to the patient. The flowrate and hematocrit measurements are used to determine fluid removed from the patient during dialysis. The ultrafiltration rates and fluid removed from the patient are used to determine the beginning blood volume of the patient.
    Type: Application
    Filed: December 3, 2018
    Publication date: June 4, 2020
    Inventors: Louis LeeGrande Barrett, Perry N. Law, Douglas L. Cox
  • Patent number: 10668204
    Abstract: Systems and sensor clip assemblies for optically monitoring blood flowing through a blood chamber are provided. A sensor clip assembly includes emitters and photodetectors positioned on opposing arms, a signal conditioning circuit for conditioning raw analog signals generated by the photodetectors while the sensor clip assembly is fastened to a blood chamber, and an analog-to-digital converter for converting the conditioned analog signals to raw digital data. The sensor clip assembly may include a microcontroller for calculating parameters of blood flowing through the blood chamber such as hematocrit, oxygen saturation, and change in blood volume from the raw digital data. The sensor clip assembly is in communication with a networked computer, and the networked computer is in communication with a remote computer configured to provide a user interface for monitoring and/or controlling the sensor clip assembly.
    Type: Grant
    Filed: August 19, 2019
    Date of Patent: June 2, 2020
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventors: Louis LeeGrande Barrett, David W. Peterson, Matthew A. Stowell, Perry N. Law
  • Patent number: 10625011
    Abstract: Embodiments of the disclosure provide a method for evaluating dialyzers used in different medical applications (e.g., hemodialysis). Red blood cell volume lost in a dialyzer is monitored by obtaining blood flowrate measurements and hematocrit measurements at input ports and output ports of the dialyzer. The flowrate and hematocrit measurements are used to determine an accumulation of red cell blood volume in the dialyzer. The measurements may be obtained in a lab environment with an in-vitro blood source or may be obtained in a clinical setting with an in-vivo blood source from a patient.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: April 21, 2020
    Assignee: Fresnius Medical Care Holdings, Inc.
    Inventors: Louis LeeGrande Barrett, Chih-Hu Ho, Eric Stroup
  • Publication number: 20190365980
    Abstract: Systems and sensor clip assemblies for optically monitoring blood flowing through a blood chamber are provided. A sensor clip assembly includes emitters and photodetectors positioned on opposing arms, a signal conditioning circuit for conditioning raw analog signals generated by the photodetectors while the sensor clip assembly is fastened to a blood chamber, and an analog-to-digital converter for converting the conditioned analog signals to raw digital data. The sensor clip assembly may include a microcontroller for calculating parameters of blood flowing through the blood chamber such as hematocrit, oxygen saturation, and change in blood volume from the raw digital data. The sensor clip assembly is in communication with a networked computer, and the networked computer is in communication with a remote computer configured to provide a user interface for monitoring and/or controlling the sensor clip assembly.
    Type: Application
    Filed: August 19, 2019
    Publication date: December 5, 2019
    Inventors: Louis LeeGrande Barrett, David W. Peterson, Matthew A. Stowell, Perry N. Law
  • Publication number: 20190365293
    Abstract: A measurement system for measuring blood characteristics includes a controller, an emitter, a sensor, and a reference sensor. The emitter emits light at a plurality of wavelengths from a first side of a blood flow channel to a second side of the blood flow channel The sensor is provided on the second side of the blood flow channel. The reference sensor is provided on the first side of the blood flow channel The controller compensates measurements from the sensor based upon measurements from the reference sensor. The reference sensor may be disposed in a position to increase noise immunity of the measurement system. The measurement system may be connected to or part of a dialysis system.
    Type: Application
    Filed: August 15, 2019
    Publication date: December 5, 2019
    Inventor: Louis LeeGrande Barrett
  • Patent number: 10471201
    Abstract: Systems and sensor clip assemblies for optically monitoring blood flowing through a blood chamber are provided. A sensor clip assembly includes emitters and photodetectors positioned on opposing arms, a signal conditioning circuit for conditioning raw analog signals generated by the photodetectors while the sensor clip assembly is fastened to a blood chamber, and an analog-to-digital converter for converting the conditioned analog signals to raw digital data. The sensor clip assembly may output the raw digital data to an external device and receive synchronized control signals from the external device, or the sensor clip assembly may include a microcontroller for performing calculations on the raw digital data and providing synchronized control signals internally. Parameters of blood flowing through the blood chamber such as hematocrit, oxygen saturation, and change in blood volume may be calculated from the raw digital data derived from the raw analog signals generated by the photodetectors.
    Type: Grant
    Filed: December 14, 2018
    Date of Patent: November 12, 2019
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventors: Louis LeeGrande Barrett, David W. Peterson, Matthew A. Stowell, Perry N. Law
  • Patent number: D979050
    Type: Grant
    Filed: October 29, 2019
    Date of Patent: February 21, 2023
    Assignee: Fresenius Medical Care Holdings, Inc.
    Inventors: Perry N. Law, Louis LeeGrande Barrett, Christopher Yim Chau