Modeling Plasma-to-Interstitium Glucose Kinetics from Multitracer Plasma and Microdialysis Data

Area of Science:

• Biomedical Engineering
• Metabolic Research
• Diabetes Technology

Background:

• Accurate glucose monitoring is vital for type 1 diabetes mellitus (T1DM) management.
• Subcutaneous glucose sensors are essential for open- and closed-loop therapeutic systems.
• Understanding plasma-to-interstitial fluid (ISF) glucose dynamics and delay is critical for sensor accuracy.

Purpose of the Study:

• To develop a kinetic model of plasma-to-ISF glucose transfer.
• To estimate the plasma-to-ISF glucose delay in healthy and T1DM individuals.
• To utilize multitracer and microdialysis data for kinetic modeling.

Main Methods:

• Employed a specific experimental design with multiple tracers and microdialysis.
• Collected simultaneous plasma and ISF glucose data frequently.
• Applied linear time-invariant compartmental modeling to steady-state tracer data.

Main Results:

• A two-compartment model accurately described plasma and ISF glucose kinetics.
• Calculated median plasma-to-ISF glucose equilibration times: 9.1 min (healthy) and 11.0 min (T1DM).
• Demonstrated precise estimation of the "equilibration time".

Conclusions:

• Plasma-to-ISF glucose kinetics in steady-state can be modeled using a linear two-compartment model.
• The "equilibration time" between plasma and ISF glucose can be accurately estimated.
• Future research will investigate kinetics during glucose/insulin perturbations.