What is a burn injury?
A burn is the destruction of skin coming into contact with a causative agent (flame, hot fluids or other material, electricity, radiation or chemical). The severity of the burn injury is determined by the amount of surface area of the skin that is damaged and the depth of tissue that is involved. Superficial injuries will heal spontaneously if appropriately treated whereas as deep injuries have no capacity for healing and require surgery. This surgery is called skin (auto) grafting: a thin layer of skin is harvested from an unburnt part of the body. Left behind are the essential components for that area to heal spontaneously but donates enough skin tissue to heal burn wound.
Burn in juries in South Africa
30 patients sustain moderate to major burn injuries in South Africa every month. Burn injuries remain a prominent external cause of morbidity and mortality in South Africa. These injuries are most prevalent in the very young (7–15/10 000 children annually). Burns comprise 12% of fatal accidents in South Africa, and are the commonest external cause of death under the age of 4 years, and the 3rd commonest under the age of 18. The burn mortality rate in South Africa is 7.9 per 100 000 person years, at least double the rate of most developed countries.
Burns remains a neglected field of health care in the country. It is the priority of the Burn Care Trust to address the deficiencies in burn care. One such component is a skin bank. A number of advances have been made in recent decades with regard to fluid resuscitation protocols, dressings, infection control strategies, antimicrobials, intensive care and nutrition for the management of the severe burn victim. These measures have reduced mortality and morbidity rates significantly over the last few decades, but the single most important intervention has undoubtedly been the implementation of early excision and autografting. Cadaver (donor) skin is recognized as the gold standard for temporary cover following early excision when insufficient autograft is available. We believe that establishment of a skin bank in South Africa will facilitate the shift to modern burn management of early excision and grafting.
The need for donor skin
Skin is the largest organ of the body and plays a critical role in management of temperature and fluid as well as protecting the body from physical and biological trauma, particularly infections. Loss of skin causes a number of alterations in the body’s functioning that do not resolve until the skin is healed or replaced.
Allograft ( cadaver or donor ) skin may be used for both superficial and deep burn wounds as a temporary measure; rejection of the skin will occur once the burn’s immunosuppressive effect resolves. In the major burn, the use of allograft skin reduces the heat and fluid loss as well as number of infections and pain associated with the major burn wound. It markedly improves the patient’s progress in the acute period. In addition to its benefits of improving the systemic manifestations of the major burn, donor skin has also been identified as improving the wound bed for autografting. Use of donor skin can result in survival and better recovery of patients with major burns that without such tissue suffer seriously and often not survive.
Fresh donor skin must be harvested and used for burn patients within days, and this necessitates the formation of skin banks where skin can be stored.
The process of the donor skin
Adherence to legal procedures and consent needs to be taken as for any organ donation. The donor’s skin is cleaned with an antiseptic solution and the harvested using a specialised blade. Only a very thin layer is taken from the legs, arms, and back. Most of the skin layers are left behind. None is taken from the face or chest. The skin is then cleaned and stored prior to use for the burn patient. Fresh donor skin must be used within 36 hours but can be stored up to 14 days if a special storage medium is used. However, cryopreservation (freezing) is a method of storage where the skin can be preserved for up to 5 years.
Besides the demand for donor skin due to the high number of burn injuries managed in South Africa, it is important to have a significant store of donor skin in the event of a national disaster in which a large number of potential major burn injuries may require allograft skin.