The Superficial Dermal Microcirculation in Suction Blister Wounds on Healthy Volunteers

Abstract

Skin blisters can be formed painlessly and in a standardized way by suction ing. The dermal blister bed can be used experimentally as a wound model in humans and in clinical practice as a means of delivering certain drugs transder mally. The superficial dermal microcirculation in blister wounds (healthy volun teers, forearm lesions, diameter: 4 mm, vacuum: 200 mmHg below atmospheric for 2.5-3.0 hours) was followed up for four days after injury by intravital video microscopy aided by computerized image analysis. On day 0 the functional microvessel length (FML [total]), assessed from wounds in different individuals, was 1687 ±403 μm/mm 2 (mean±SD), the diameter 11±1 μm, and the density of papillary loops 29±5 per mm2. Red blood cell velocity (RBC-V) was 0.61±0.17 mm/s. Time courses for these parameters were described. The earliest signs of neovascularization were noted on day 1, and by day 4 papillary loops with new formations were in the majority. Wounds that had been occlusively covered with polyester film were more edematous and had lower RBC-V values than wounds where the epidermal roof had remained in situ. All lesions healed rapidly with out complications or visible scar. The means of quantitating neovascularization is of particular interest for the wound model application. Clinically, the pres ence of a functioning superficial microvessel network may facilitate an even drug resorption.