Histopathological evaluation of scalds and contact burns in the pig model.

A method was developed to inflict standardized scald burns in the New Yorkshire pig. The tissue damage was compared to a standardized contact burn model. On each flank, six localizations were marked in a symmetrical way. Eight scald burns covering 45 cm2 were inflicted by exposing the prepared skin to 500 ml tap water in an applicator at 80 degrees C for 10, 20, 30 and 40 s. Four contact burns were inflicted by applying a brass block of 45 cm2 area, weight 450 gram, with a temperature of 170 degrees C for 10 and 20 s on the skin without exerting pressure. The right flank was used for macroscopic observation, the left flank for histopathological evaluation. Full thickness biopsies were taken at postburn days (PBD) 0, 1, 2, 3 and 21. In the contact burns, a clear demarcation zone of viable and necrotic dermal tissue and vascular damage was observed. The tissue damage in the scalds showed an intermingled pattern of intact and damaged collagen. The more severe scald burns showed a structurally intact superficial vascular plexus, in combination with destruction of the deep vascular plexus. Current and new methods of scald treatment can be classified in this standardized animal model.