US 12,765,812 B2 · Systems and methods for noninvasive monitoring of the body fluid status and hemoglobin, and using the same for an automated decision support

Abstract

Methods and apparatus for multi-wavelength (MW) photoplethysmography (PPG)-based trend monitoring are used to monitor changes in total hemoglobin, fluid accumulation in circulation (plasma volume) and tissues (interstitial fluid volume), total blood volume, and tissue perfusion (microcirculation). The methods and systems provide integration of automated decision support in both medical-grade and non-medical grade wearables for continuous body fluid management guided by MW PPG measurements. Recommendations for optimizing physiological function, including management of fluid intake, restriction or removal, co-administration of cardiovascular medication, and red blood cell transfusion may be provided. Blood loss detection and transfusion-related recommendations may be made based in assessing whole-body hemoglobin mass changes by differentiating dilution-related variations in hemoglobin concentration from net changes in hemoglobin mass due to red blood cell loss or transfusion. Plasma dilution-related fluctuations in plasma volume and corresponding blood volume changes may also be monitored alongside fluctuations in tissue fluid volume and transcapillary fluid shifts. The system may provide clinically relevant trend data for clinician interpretation and real-time alerts for assessing fluid status, including intravascular and extravascular fluid accumulation, total blood volume changes, plasma volume, and net hemoglobin mass variations. Clinical guidance on fluid management, real-time alerts for imminent edema or dehydration risks, and notifications regarding potential blood loss or transfusion effects on hemoglobin levels may be provided. In a non-clinical setting, the system advises on fluid intake or restriction based on fluid accumulation trends in circulation and tissues which are an indication of plasma and tissue hydration status, and prompts users to seek medical attention when a significant reduction in hemoglobin is detected.

Claims20

Dependent claims

A method for monitoring hydration status and detection of changes in whole body hemoglobin mass of a subject comprising:

i) obtaining multi-wavelength photoplethysmography information associated with light that has passed through the derma of the subject;
ii) setting a minimum hemocrit (Hct) value and a maximum Hct value defining lateral boundaries;
iii) setting dehydrated plasma dilution (dPD) value as a lower boundary;
iv) setting an optimal plasma dilution (oPD) as an upper boundary;
v) processing the multi-wavelength photoplethysmography information to derive:
(1) a first parameter associated with plasma dilution (PD);
and
(2) a second parameter associated with Hct,
vi) generating a nomogram including a rhombus shape defined by the minimum Hct, maximum Hct, dehydrated plasma dilution and optimal plasma dilution, and
vii) fitting the first parameter and the second parameter on the nomogram, wherein normal hydration is indicated where the first parameter and second parameter fit inside the rhombus shape, wherein a reduction in whole body hemoglobin mass is indicated where the first parameter and second parameter fit outside the rhombus shape above the optimal plasma dilution (oPD) as the upper boundary, and/or wherein an increase in the whole body hemoglobin mass is indicated where the first parameter and second parameter fit outside the rhombus shape below the dehydrated plasma dilution (dPD) value as the lower boundary.

7 more elements

Dependencies are inferred from the claim text.

Systems and methods for noninvasive monitoring of the body fluid status and hemoglobin, and using the same for an automated decision support

Life of this patent

Systems and methods for noninvasive monitoring of the body fluid status and hemoglobin, and using the same for an automated decision support

Life of this patent

Abstract

Claims20