Rectal temperature changes of Wistar rats with second-degree scald burn in hot and humid environment following...

To observe the changes in rectal temperature (Tr) after immediate cooling therapy for Wistar rats with superficial second-degree scald burn in hot and humid environment, and evaluate the effect of the dressing material for cooling.

Twenty-four Wistar rats were randomly divided into 4 groups (n=6), namely normal temperature control (NTC), normal temperature cooling therapy (NTCT), hot and humid control (HHC), and hot and humid cooling therapy (HHCT) groups. Superficial second-degree scald burns were induced in the rats, followed by interventions with cooling therapy in the two therapy groups at dry bulb temperature (Tdb) of 35.33+/-0.35 degrees Celsius with relative humidity of 70.81%+/-1.38%, whereas the two control groups were treated at Tdb of 26.33+/-1.29 degrees Celsius with relative humidity of 71.05%+/-4.57% without dressing for cooling therapy. The exposure time of each group was 120 min, and the Tr was recorded every 20 min.

On the basis of comparisons between the measurements taken at 7 different time points, we found that the Tr of the rats was elevated in hot and humid environment (P<0.001) and decreased when cooling therapy was applied (P<0.001). Interactions between the environmental temperature and cooling therapy were noted in their influence on Tr (P=0.003). As the exposure time was prolonged, Tr slowly decreased in NTC group, mildly fluctuated in NTCT group, but elevated in HHC and HHCT groups with gradual increase of the differences between the measurements taken at the same time point.

Application of the dressing material on the abdomen for cooling therapy can efficiently lower the Tr, which may prevent the progression of the heat injury.