Dried gamma-irradiated amniotic membrane as dressing in burn wound care

Rationale: Dried amniotic membrane contains collagen matrix and key bioactive molecules like fibronectin, laminin, glycosaminoglycans and elastin. Fresh and cryopreserved human amniotic membrane has been widely explored as a biological dressing. However, fresh and cryopreserved amniotic membranes are not readily available or require special storage conditions. This investigation was aimed to study the functional and clinical efficacy of air-dried radiation sterilized amniotic membranes as dressing in burn wound care. Methods: Amniotic membranes collected from placentae of screened donors were processed and sterilized by gamma radiation at 25 kGy. The fluid handling capacity, shelf life and clinical efficacy of air-dried gamma-irradiated amniotic membranes was evaluated. Results: Fluid handling capacity of the air-dried irradiated amniotic membrane dressing was 3.79-4.2 g/10 cm(2) in 24 h. Infrared (IR) spectral scanning showed no degradation or change in the dried gamma-irradiated amniotic tissue after 2 and 5 years of storage. No effect of storage on the impermeability of the processed amniotic membranes to bacteria was observed. The dried gamma-irradiated amniotic membranes even after 5 years of storage provided an effective barrier to microbial penetration. The dried amniotic membranes were applied to 22 cases of scald, flame and electrical burns. Of the 22 patients studied, 19 patients had excellent results in the form of complete epithelialization of wound with an average healing time of 15-25 days. Conclusion: IR studies and microbial permeability test indicate no qualitative changes in the material property of dried gamma-irradiated amniotic membranes after 2 and 5 years of storage. Air-dried amniotic membrane with the advantage of storage at room temperature as well as functional efficiency is an ideal dressing for burn wound care. (C) 2010 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.