**4. Clinical indications**

Scarectomy and prompt coverage have increased the survival of major burnt patients. However, on many occasions, the available skin for autografts is limited, and the lack of donor areas impedes grafting the totality of the excised areas. In the latter conditions, the SA has become the reference cutaneous substitute, which can be used alone or combined with autografts. Other SA clinical indications among burnt patients are bedding with doubtful vitality or infection, or when the autograft procurement significantly increases the morbimortality of the patient.

The current role of the SA in treating burns varies among the burnt units or centers, where most of them lack the access or experience of using this product [50].

#### **4.1 Sole skin allografts use**

#### *4.1.1 Lack of donor areas*

When donor areas are minimal or lacking, a scarectomy and coverage with SA are done directly on the residual bedding, which is replaced after the healing of intermediate burns, and the donor areas allow the harvesting of new autografts.

It is vital to emphasize that in burnt inpatients, the hospitalization time and economic costs are lower in the group of patients who first receive an SA followed by an autograft than in the group that only receives autografts. The latter could probably be since the autograft obtention generates new bloody areas and that the autograft in a non-completely defined vitality could imply its loss [51].

*Banks of Cryopreserved Skin from Live Donors and Total Skin Allografts in the Surgery of… DOI: http://dx.doi.org/10.5772/intechopen.104451*

#### *4.1.2 Engraftment test*

When the bedding to cover has a doubtful vitality, the use of SA is preferred, since it permits an engraftment evaluation before using autografts. As autologous skin grafts, CTSCAs suffer revascularization, providing the wound bedding with crucial growth factors and cytokines, promoting cellular chemotaxis and proliferation.

The increased wound bedding vascularization stimulates angiogenesis and favors the bedding preparation for an autologous skin graft.

Another indication for using allografts in burns surgery could be in the context of infected burns when the risk of losing the autograft is considered significant [52, 53].

### *4.1.3 Unstable patient*

Scarectomy of extensive body surfaces, mainly associated with the autografts harvesting in the same surgical time, produces significant bleeding. Using SA, scarectomy may be done alone and the graft harvesting during a second time, reducing the bleeding and hemodynamic instability.

#### **4.2 Use of SA associated with autografts**

Alexander et al. described the "In sandwich compound graft." Following the scarectomy of the burnt patient, the bedding was covered with expanded autografts (meshed 1/6 or higher), which were then covered by a SA expanded in smaller meshes (1/1, 5, or 1/3). The latter worked as tutors and avoided the autograft dissection. This technique allows the coverage of extensive body surfaces with high success rates. Besides, Cuono et al. demonstrated that the engraftment of keratinocyte culture grafts improved significantly using dermic bedding provided by allografts [ 54, 55].
