ObjectiveComparison of cultured skin substitutes (CSS) and split-thickness skin autograft (AG) was performed to assess whether donor-site harvesting can be reduced quantitatively and whether functional and cosmetic outcome is similar qualitatively in the treatment of patients with massive cutaneous burns. Summary Background DataCultured skin substitutes consisting of collagen-glycosaminoglycan substrates populated with autologous fibroblasts and keratinocytes have been shown to close full-thickness skin wounds in preclinical and clinical studies with acceptable functional and cosmetic results. MethodsQualitative outcome was compared between CSS and AG in 45 patients on an ordinal scale (0, worst; 10, best) with primary analyses at postoperative day 28 and after about 1 year for erythema, pigmentation, pliability, raised scar, epithelial blistering, and surface texture. In the latest 12 of the 45 patients, tracings were performed of donor skin biopsies and wounds treated with CSS at postoperative days 14 and 28 to calculate percentage engraftment, the ratio of closed wound: donor skin areas, and the percentage of total body surface area closed with CSS.

ObjectiveComparison of cultured skin substitutes (CSSs) and split-thickness autograft (STAG) was performed to assess whether the requirement for autologous skin grafts may be reduced in the treatment of massive burns. Summary Background DataCultured skin substitutes consisting of collagen-glycosaminoglycan substrates populated with autologous fibroblasts and keratinocytes have been demonstrated to close full-thickness skin wounds in athymic mice and to express normal skin antigens after closure of excised wounds in burn patients. MethodsData were collected from 17 patients between days 2 and 14 to determine incidence of exudate, incidence of regrafting, coloration, keratinization, and percentage of site covered by graft (n = 17). Outcome was evaluated on an ordinal scale (0 = worst; 10 = best) beginning at day 14, with primary analyses at 28 days (n = 10) and 1 year (n = 4) for erythema, pigmentation, epithelial blistering, surface roughness, skin suppleness, and raised scar. ResultsSites treated with CSSs had increased incidence of exudate (p = 0.06) and decreased percentage of engraftment (p < 0.05) compared with STAG. Outcome parameters during the first year showed no differences in erythema, blistering, or suppleness. Pigmentation was greater, scar was less raised, but regrafting was more frequent in CSS sites than STAG. No differences in qualitative outcomes were found after 1 year, and antibodies to bovine collagen were not detected in patient sera. ConclusionsThese results suggest that outcome of engrafted CSSs is not different from STAG and that increased incidence of regrafting is related to decreased percentage of initial engraftment. Increased rates of engraftment of CSSs may lead to improved outcome for closure of bum wounds, allow greater availability of materials for grafting, and reduce requirements for donor skin autograft. 743

Objectives Stable closure of full-thickness burn wounds remains a limitation to recovery from burns of greater than 50% of the total body surface area (TBSA). Hypothetically, engineered skin substitutes (ESS) consisting of autologous keratinocytes and fibroblasts attached to collagen-based scaffolds may reduce requirements for donor skin, and decrease mortality. Methods ESS were prepared from split-thickness skin biopsies collected after enrollment of 16 pediatric burn patients into an approved study protocol. ESS and split-thickness autograft (AG) were applied to 15 subjects with full-thickness burns involving a mean of 76.9% TBSA. Data consisted of photographs, tracings of donor skin and healed wounds, comparison of mortality with the National Burn Repository (NBR), correlation of TBSA closed wounds with TBSA full-thickness burn, frequencies of regrafting, and immunoreactivity to the biopolymer scaffold. Results One subject expired before ESS application, and 15 subjects received 2056 ESS grafts. The ratio of closed wound to donor areas was 108.7±9.7 for ESS compared with a maximum of 4.0±0.0 for AG. Mortality for enrolled subjects was 6.25%, and 30.3% for a comparable population from the NBR (p<0.05). Engraftment was 83.5±2.0% for ESS and 96.5±0.9 for AG. Percentage TBSA closed was 29.9±3.3% for ESS, and 47.0±2.0 for AG. These values were significantly different between the graft types. Correlation of % TBSA closed with ESS with % TBSA full-thickness burn generated an R2 value of 0.65 (p<0.001). Conclusions These results indicate that autologous ESS reduce mortality and requirements for donor skin harvesting, for grafting of full-thickness burns of greater than 50% TBSA.

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