Guidelines on processing and clinical use of skin allografts

Abstract

Processing methods used for banking of skin for subsequent therapeutic use depend on whether the skin is to retain viability or not. For viable skin grafts, sterilisation techniques cannot be applied, however antibiotics and antimycotics may be used to disinfect the tissue with respect to bacteria and fungi. Nevertheless, strict standards are applied to avoid disease transmission from donor to recipient involving donor medical history, donor testing for viral diseases, aseptic retrieval and processing, and control of storage temperature. Cryopreservation is the preferred method for long term storage of viable skin grafts. If viability is not required, then additional long term preservation methods may be used including deep-freezing, freeze-drying or high concentration solute preservation. All three methods work by reducing water activity. In addition it is possible to apply certain sterilisation techniques that have been shown not to damage the tissue. It is important that sterilisation methods are validated in accordance with precise definitions of sterilisation, and for the initial levels of "bioburden" expected to be present immediately prior to application of the sterilisation method. The application of improved and refined methodologies in accordance with defined standards has ensured improved graft performance while reducing risk to the recipient.

Current insights into skin banking: storage, preservation and clinical importance of skin allografts

“…Antibiograms are performed in the case of positive results. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] According to a recent study by Pirnay et al, 32 an incubation time of 14 days allows an additional 16.9% of contaminated skin to be detected compared with the traditional 3-day incubation protocol. The authors also noted that 24% of the slow-growing bacteria detected after 14 days could be considered potentially pathogenic.…”

“…The skin contamination rate may also be reduced. 7,16 Procurement from living donors is carried out with the same standards as for cadaver donors: in most cases, living donors are patients undergoing abdominoplasty who consent to tissue donation.…”

“…According to international guidelines and national legislation, the safety requirements of donor skin (whether from cadavers or living donors) must be guaranteed by special procedures and quality standards. [15][16][17][18][19] To reduce the risk of transmission of diseases through skin transplantation, potential donors are selected on the basis of comprehensive medical and social (personal, behavioral) data, including travel history, physical examination and serological and microbiological testing. Minimum serological screening for HIV, hepatitis B and C and syphilis, and optional testing for human T-lymphotrophic virus, cytomegalovirus, ABO grouping and Rh typing are performed by most skin tissue banks.…”

“…The increasing demand for donor skin grafts to manage severe burns, trauma and soft tissue injuries has led to the creation of skin banking facilities, 14 stimulating research into skin processing methods. [12][13][14][15][16][17] All patients provided written informed consent for their accompanying images to be published for this review.…”

Skin Graft Preservation

“…Once the skin is removed from the body, it can be cooled rapidly by immersion into a refrigerated solution, thus immediately reducing the rate of cell death. In the other hand, tissue banking standards generally set limits on the maximum warm and cold ischemia times permitted after the death of the donor, because it is known that bacteria from the gut can be released into the vascular system postmortem and migrate to the internal organs and tissues (Kearney, 2005).…”