Method for using photoplethysmography to optimize fluid removal during renal replacement therapy by hemodialysis or hemofiltration

• US 9,155,826 B2
• Filed: 01/06/2011
• Issued: 10/13/2015
• Est. Priority Date: 09/15/2006
• Status: Active Grant

• Current Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Original Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Inventors: Ross, Edward Allan, Melker, Richard J.
• Primary Examiner(s): Zalukaeva, Tatyana
• Assistant Examiner(s): TREYGER, ILYA Y
• Application Number:
  US12/985,435
• Publication Number:
  US 20110098545A1
• Time in Patent Office: 1,741 Days
• Field of Search: 604/5.04, 604/6.11, 604/9
• US Class Current: 1/1
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/6819 Nose
• CPC Class Codes: A61M 1/34 Filtering material out of the blood by passing it through a membrane, i.e. hemofiltration or diafiltration
• CPC Class Codes: A61M 1/3403 Regulation parameters
• CPC Class Codes: A61M 1/341 by measuring the filtrate rate or volume
• CPC Class Codes: A61M 1/3609 Physical characteristics of the blood, e.g. haematocrit, urea
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/50 with microprocessors or computers

Abstract

Disclosed herein are methods, systems and devices to monitor vascular volume status during renal replacement therapy utilizing at least one oximetry/photoplethysmography sensor. The methods, systems and devices provide an alternative to conventional vascular volume monitoring methods during renal replacement therapy while enabling reliable, non-invasive, and automatic monitoring of vascular volume to avert patient hypotension. The methods, systems and devices may be employed in the context of both inpatient and outpatient dialysis facilities and may also be incorporated into conventional hemodialysis and hemofiltration techniques and equipment.

Claims

1. A device for monitoring and controlling renal replacement therapy, said device comprising

a computer that communicates with at least one pulse oximeter/photoplethysmography probe, said computer comprising

at least one processing module;

a first computer-readable program code module that causes said computer to separate a signal stream from said at least one pulse oximeter/photoplethysmography probe into an isolated pulsatile cardiac component signal stream, an isolated venous capacitance component signal stream, or both;

a second computer-readable program code module that causes said computer to analyze said isolated pulsatile cardiac component signal stream and/or said isolated venous capacitance component signal stream to determine changes in blood flow, blood volume status, or both; and

a third computer-readable program code module that causes said computer to adjust said renal replacement therapy, without need for user input, in response to a change in said isolated pulsatile cardiac component signal stream and/or said isolated venous capacitance component signal stream, whereby said therapy is adjusted until said isolated pulsatile cardiac component signal stream and/or said isolated venous capacitance component signal stream is modulated to a target level.

2. The device of claim 1, further comprising a display screen effective to display information to a user of said device.

3. The device of claim 1, wherein said third computer-readable program code module adjusts said renal replacement therapy in response to a change in an area under the curve (AUC) of said isolated pulsatile cardiac component signal stream and/or an AUC of said isolated venous capacitance component signal stream.

4. The device of claim 1, wherein said third computer-readable program code module adjusts said therapy in response to a change in an amplitude of said isolated pulsatile cardiac component signal stream and/or an amplitude of said isolated venous capacitance component signal stream.

5. The device of claim 1, wherein adjusting said therapy comprises increasing or decreasing a fluid removal rate.

6. The device of claim 5, wherein adjusting said therapy comprises decreasing said fluid removal rate.

7. The device of claim 5, wherein said fluid removal rate is an ultrafiltration rate.