[Cutaneous microvascular flow studied by laser-Doppler. A study of 100 healthy volunteers]

Cutaneous capillary flow (tip of the 3rd right finger) was measured with a laser Doppler (Periflux, Perimed), in 100 healthy volunteers without any history of hypertensive or vasospatic diseases, 15 females smoke and were taking contraceptive drugs. Smokers (n = 16 M, 25 F) stopped smoking 3 hours before the study. Basal laser Doppler flux (BLDF), amplitude of vasomotion waves (AV), post-occlusive reactive hyperthermia peakflow (F Max), difference between BLDF and F Max (delta F Max), time to reach 50 percent of the initial value (t1/2 r) and total recovery (tr), t Max (peak of over-shoot) and t/2 over shoot were measured. F Max after heating stimulus (40 degrees) (f Max H), delta F Max H (difference between BLDF and F Max H) and t Max H time (mn) to reach F Max H were measured before a cold stimulus was applied. Results were expressed in arbitrary units (cvolts), BLDF showed inter-individual variation but was reproducible over months in the same subject. The basal flux was statistically different between males (352.7 +/- 21.7) and females (249.6 +/- 22.4). Spontaneous vasomotion waves and different times (in sec.) to reach the peak after three minutes of arterial occlusion could be measured with this technique. These normal range of values can allow comparison and assessment of variations in pathological conditions, mainly Raynaud's phenomenon, high blood pressure, diabetes, smokers, sickle-cell anemia. Acute pharmacological tests can be carried out with drugs showing specific action on microcirculation and spontaneous vasomotion.