A Novel Fluorescent Clinical Method to Rapidly Quantify Plasma Volume.

Area of Science:

• Biomedical Engineering
• Clinical Chemistry
• Pharmacokinetics

Background:

• Accurate plasma volume (PV) measurement is crucial for fluid management.
• Existing methods for PV determination can be invasive or time-consuming.
• Rapid and reliable PV assessment is needed in various clinical settings.

Purpose of the Study:

• To evaluate the performance of a novel rapid fluorescent indicator technique for measuring plasma volume (PV).
• To assess the accuracy and reproducibility of this technique in healthy subjects and patients with chronic kidney disease (CKD).
• To determine the stability of the plasma volume marker (PVM) and monitor dynamic changes in PV.

Main Methods:

• An open-label, observational study involving 32 subjects (16 healthy, 16 CKD).
• A two-component intravenous fluorescent dye technique using a large dextran conjugate as the PV marker (PVM).
• Indicator-dilution principle for initial PV measurements, with extended monitoring for PVM stability and pharmacokinetic analysis.

Main Results:

• The fluorescent dye technique provided rapid, accurate, and reproducible PV and blood volume (BV) measurements.
• PV and BV varied with body size, showing stability for over 6 hours.
• Results showed general agreement with Nadler's formula, with low variability in repeat measurements and accurate detection of fluid administration effects.

Conclusions:

• The minimally invasive fluorescent dye approach offers a safe, rapid, and accurate method for PV and BV determination.
• This technique allows for reproducible measurements and dynamic monitoring of PV changes.
• The method is suitable for use in both healthy individuals and patients with chronic kidney disease.