Effects of localized cutaneous vascular alteration on reactive hyperemia.

Background: Cutaneous microcirculation shows a distinctive spatiotemporal inhomogeneity. Therefore provocation tests are necessary to receive significant and reproducible data. The present study investigated the effect of localized cutaneous vascular alteration, like in psoriasis vulgaris, on different parameters of reactive hyperemia (peak capillary blood cell velocity [pCBV], postocclusive reactive hyperemia [PRH%], and time to peak capillary blood cell velocity [tpCBV]).

Material And Methods: Psoriatic plaques and normal skin on the contralateral side of 20 patients with psoriasis vulgaris were examined by Laser Doppler Anemometry. Capillary blood cell velocity was measured before suprasystolic occlusion and during postocclusive hyperemia.

Results: Compared to normal skin psoriatic plaques showed a significant increase of peak capillary blood cell velocity (pCBV, normal skin: 0.89+/-0.23 mm/s, psoriatic plaque: 2.03+/-0.94 mm/s), resting capillary blood cell velocity (rCBV, normal skin: 0.43+/-0.12 mm/s psoriatic plaque: 0.72+/-0.20 mm/s) and postocclusive reactive hyperemia (PRH%, normal skin: 107%, psoriatic plaque: 180%). The time to peak capillary blood cell velocity (tpCBV) during reactive hyperemia did not change significantly.

Conclusion: In reactive hyperemia, changing of pCBV and PRH% combined with unaltered tCBV indicate a dysfunction of cutaneous microcirculation. In contrast acute closure of upper and lower arterial extremity show a changed tCBV with stable pCBV and PRH%.