Laura L. Bolton

Occlusive dressings: Therapeutic agents and effects on drug delivery

Abstract Dressings have been applied to wounds and skin for diverse purposes throughout the centuries. In 1500 B.C., the Egyptians spread honey and ibex grease on an open-weave papyrus bandage, after packing with extra-absorbent lint for exudative wounds. 1 As time passed, a variety of imaginative measures 2 were applied to healing wounds, with the result that repair often occurred in spite of the dressings rather than because of them. Controlled studies were rare, so scientific knowledge about the effect of dressings on healing and the skin progressed little from the ancient Egyptians to the 19th century. The increasing scientific study of dressings in the 20th century, combined with new tools to measure various aspects of dressing performance and wound healing, spawned a growing awareness of the role of dressings as barriers in healing, debridement, sequestering of growth factors, drug delivery, and infection control and as skin replacements. Current knowledge of each of these areas is reviewed.

Effect of Calcium Alginate Dressings on Partial-Thickness Wounds in Swine

The epithelization of partial-thickness wounds (PTW) has been shown to be enhanced with the use of moisture-retentive dressings (MRD), and not with nonmoisture-retentive dressings (NMRD) like gauze. This study was designed to explore this effect using two different alginate products with and without MRDs. We evaluated these alginate dressings under a polyurethane film dressing (FMRD) and under an NMRD gauze. They were compared to hydrocolloid moisture-retentive dressings (HMRD). Twelve PTW measuring 22 x 22 x 0.5 mm were made on the dorsum of six swine with a Castroviejo dermatome. Return of the epithelial barrier function was measured with an EP1 ServoMed evaporimeter. On postoperative day 4, the first alginate product under the NMRD and under the FMRD had a significantly slower healing rate than the HMRDs. By postoperative day 7, the second alginate product under the NMRD had a poorer rate of epidermal wound healing than the HMRD. Our results indicate that these alginate products have a satisfactory partial-thickness wound healing capability when used under MRDs. When used under MRDs, the return of the epithelial barrier function is delayed, indicating that these dressings should not be used on dry wounds or under gauze dressings.