Reproducibility of a local cooling test to assess microvascular function in human skin

Area of Science:

• Physiology
• Biomedical Engineering
• Vascular Biology

Background:

• Assessing skin microvascular reactivity is crucial for understanding vascular health.
• Laser-Doppler flowmetry (LDF) is a key tool for measuring skin blood flow.
• Reproducibility of microvascular reactivity tests is essential for reliable clinical application.

Purpose of the Study:

• To evaluate the reproducibility of a custom-designed laser-Doppler flowmetry (LDF) probe for assessing skin microvascular reactivity during local cooling.
• To compare the reproducibility of short-term (5-min) versus longer-term (30-min) cooling protocols.

Main Methods:

• Twenty-two healthy volunteers participated in the study.
• Local forearm cooling at 15°C was applied for either 5 or 30 minutes.
• Skin blood flow was measured using LDF, with repeated measurements to assess reproducibility (CV, ICC).

Main Results:

• The 5-minute cooling protocol showed good immediate reproducibility (CV 8-18%, ICC 0.78-0.85).
• The 30-minute cooling protocol exhibited higher reproducibility at one week (CV 23-26%, ICC 0.75-0.86).
• Local cooling was well-tolerated by all participants.

Conclusions:

• A 30-minute LDF cooling test offers a reproducible method for assessing skin microvascular reactivity.
• This test has potential applications in evaluating microvascular function in diseases like Raynaud's syndrome.
• The developed tool can aid in the evaluation of therapeutic drugs targeting microvascular disorders.