Should dermal scald burns in children be covered with autologous skin grafts or with allogeneic cultivated keratinocytes?—“The Viennese concept”
Introduction
The use of cultured epidermal autografts for the coverage of burn wounds was introduced by Rheinwald and Green [1] and Gallico et al. [2] in the nineteen seventies. Despite many criticisms, in the hands of many burn surgeons it has become a proven method, which can help to save the life of severely burned patients [3], [4], [5]. Nevertheless, especially in the case of autologous use, there are still persistent problems such as the relatively long culture time. It takes about 3–5 weeks to reach sheet grafts, which are suitable for grafting. Moreover, a significant number of severely burned individuals succumb to their injuries during this culture period. A further persisting problem is the observed lack of stability (blistering) in comparison to with split thickness grafted areas. This instability is mainly based on the lack of rete ridges and hemidesmosomes, which have been shown to need several months for their formation [6]. Therefore, many centres in Europe have started to use either fresh or cryopreserved allografts [7].
Due to the release of growth factors and wound healing mediators, it has been claimed that cultured epidermal allografts have a beneficial effect in the treatment of superficial and partial thickness burns [7], [8], [9].
In the burn unit of the Department of Plastic and Reconstructive Surgery at the Vienna University Hospital a programme of cultivation of human epidermal cells was established in 1995. Since 1997 more than 600 sheets of cultured keratinocytes, 75 cm2 in size, have been produced each year. Beside the coverage of partial thickness burns in the face [10] and hands as well as the coverage of skin graft donor sites, one of the main indications for the use of allogeneic cultivated keratinocytes is the coverage of partial thickness scalds in children [11].
However, the treatment of partial thickness scalds in children is still discussed controversially. Whereas several authors have proposed the early excision of scalds and grafting with skin grafts or biological skin substitutes [12], others have advocated a delay of at least 10 days until definitive coverage in order to minimize the operative trauma and blood loss [13].
In 2001, Yanaga et al. showed that coverage with allogeneic cultivated keratinocytes leads to a faster epithelisation of excised scald wounds in comparison to the treatment without any coverage in children [14]. They also reported of faster epithelisation of donor sites covered with keratinocytes in comparison to those treated conservatively. They demonstrated a milder redness and scar formation in the grafted areas due to earlier wound closure and thereby better functional outcome. According to these findings, the clinical outcome using allogeneic cultivated keratinocytes can be considered to be superior upon conservative or surgical strategies in which no further wound coverage will be achieved.
On the other hand, wound coverage can usually be adequately achieved with split skin grafts in children [13]. In regard to the higher risks in developing hypertropic scar formation and contracture in donor sites as well as in scald wounds, covered with split skin grafts, Lochbuhler and Meuli presented new concepts in paediatric burn care in order to refine the surgical techniques and to improve the clinical outcome in 1992 [15], [16].
Due to the fact that wound coverage with autologous split skin grafts can lead to an acceptable functional and aesthetic outcome, one should compare the clinical results obtained in children, where the wounds were covered with biological skin substitutes with those, who received split skin grafts in order to highlight the advantages of the treatment with cultured allogeneic keratinocytes in scald wounds in children. This retrospective study introduces our concept in treating partial thickness scalds in children and compares follow-up results after the use of allogeneic cultivated keratinocytes to those after skin grafting. The aim of the study was to answer following questions:
- •
Does the use of allogeneic cultivated keratinocytes render constant and reliable results in children with partial thickness scalds during a follow-up period of at least 17 months?
- •
Is the actual intraoperative blood loss less using allogeneic keratinocytes in comparison to the exclusive use of skin grafts?
- •
Is the hospitalisation time reduced by the use of keratinocytes in comparison to the “conventional” skin graft treatment?
- •
Is there any impact on scar formation after wound coverage with keratinocytes in comparison to the coverage with skin grafts?
Section snippets
Material and methods
Between 1997 and 2002, 124 children underwent surgical intervention to treat burn injuries in our clinical department. Thirty-six out of these 124 children were included into this study. Inclusion criteria were comparable affected TBSA, burn depth and age (refer to Table 1). All enrolled children were surgically treated by the same experienced operation team. Twenty-two out these 36 children with an average age of 19.2 ± 8.8 months and all with partial thickness scald wounds covering an average
Results
In all children, a complete healing of all excised areas either covered with allogeneic keratinocytes or split skin grafts could be achieved. In the keratinocyte group, the mean volume of blood which had to be transfused intra- and post-operatively was 63.9 ± 83.6 ml and thereby significantly less than the volume of 151.4 ± 154.7 ml transfused in the skin graft group (p = 0.04). Moreover, half of the children of the keratinocyte group got no blood transfusion preoperatively at all, whereas in the
Discussion
The present study is focused on the clinical use of skin grafts and biological skin substitutes for the coverage of scald wounds in children. One objective was to highlight the advantages of the treatment with allogeneic cultivated keratinocytes. In accordance with the results of Yanaga et al. [14] the data obtained clearly demonstrate that the use of allogeneic keratinocytes is a reliable method for the treatment of partial thickness scalds in childhood. In cases of full thickness scalds, in
References (17)
- et al.
Cultured epithelial autografts in extensive burn coverage of severely traumatized patients: a 5-year single-centre experience with 30 patients
Burns
(2000) - et al.
Quantification of functional results after facial burns by the faciometer®
Burns
(2000) - et al.
A guide to biological skin substitutes
Br J Plastic Surg
(2002) - et al.
Cryopreserved cultured epidermal allografts achieved early closure of wounds and reduced scar formation in deep partial thickness burn wounds and split-thickness skin donor sites of paediatric patients
Burns
(2001) - et al.
Serial cultivation of strains of human epidermal keratinocytes: the formation of keratinizing colonies from single cells
Cell
(1975) - et al.
Permanent coverage of large burn wounds with autologous cultured human epithelium
N Engl J Med
(1984) - et al.
Cultured epidermal autografts and allodermis combination for permanent burn wound coverage
Burns
(1994) Cultured skin for massive burns: a prospective, controlled trial
Ann Surg
(1996)