Optimal back-extrapolation method for estimating plasma volume in humans using the indocyanine green dilution method

Area of Science:

• Physiology
• Medical Imaging
• Mathematical Modeling

Background:

• The indocyanine green (ICG) dilution method is utilized for plasma volume estimation.
• Concerns exist regarding the accuracy of the traditional ICG dilution method.

Purpose of the Study:

• To develop a physiologically based mathematical model for ICG kinetics.
• To create an improved back-extrapolation method for accurate plasma volume estimation.

Main Methods:

• Developed a novel mathematical model simulating ICG kinetics post-injection.
• Utilized the model to derive an optimal back-extrapolation technique.
• Validated the method in a clinical study with type 2 diabetes patients.

Main Results:

• The proposed method yielded significantly higher plasma volume estimates (35.1 mL/kg) than the traditional method (26.8 mL/kg).
• Results from the new method align better with previously reported plasma volume values.
• Demonstrated improved accuracy and physiological relevance in plasma volume determination.

Conclusions:

• The new back-extrapolation method offers a more physiologically accurate representation of ICG kinetics.
• This improved method is recommended for plasma volume estimation using the ICG dilution technique.
• Enhanced accuracy supports more reliable clinical assessments.