The effect of different cooling temperatures and immersion fluids on post-burn oedema and survival of the partially scalded hairy mouse ear.

One ear of NMRI hairy mice was first scalded and then immediately immersed in cold water or saline at 8 degrees C, 15 degrees C, 20 degrees C, 25 degrees C or 30 degrees C for a period of 30 min in order to study oedema formation and the therapeutic effect at 4 days. Oedema was determined by wet-dry weight measurements of punch biopsies from the ear and expressed as an increase in tissue water content. The therapeutic effects at 4 days were determined by observing the survival of the ear; the area of necrosis was expressed in per cent of the total area of the ear. Significant oedema was found in all scalded ears. A partial (15 per cent) dry necrosis of the untreated burned ear had developed within 4 days. Cooling in 8 degrees C water or saline for 30 min post-burn significantly reduced oedema in this model as determined 2h post-burn. However, 4 days post-burn all cooled ears showed a 15 per cent necrosis.