OBJECTIVETo establish a rat model of scalding with controllable depth and area by high pressure steam.

METHODSHigh pressure steam apparatus consisting of an autoclave and a self-made scalding frame was employed in the study. The rats were inflicted with scalding with 0.12 Mpa (1 Mpa = 7500 mmHg) high pressure steam on the back through a hole of 2.6 cm in diameter for 3, 4, 5, 6, 7, 8, 9 and 10 seconds, with five wounds at each time point. The tissue samples were harvested at 24 post injury hour (PIH) for pathomorphological examination. The depth of scald was measured, and injury to the sweat gland and hair follicles injury, the hair growth in scalded area, and the wound healing condition were observed with Photoshop software.

RESULTSThere was positive correlation between the scalding depth and scalding time. The injury time for superficial and deep partial thickness burn and full thickness burn were 3, 5 and 7 seconds respectively. The wound healing time was similar even the scalding became more and more serious when injury time increased from 7 to 10 seconds.

CONCLUSIONThe scalding depth and area in this model could be controlled, and the degree of scald injury could be graded accurately with easy manipulation. The result showed that it was an ideal model of skin burn wound.