Experimental study on alkaline skin injuries--periodic changes in subcutaneous tissue pH and the effects exerted by washing.

A skin alkaline injury model was constructed using rats and 2N-NaOH. The changes over time, paying special attention to subcutaneous tissue pH, were recorded and included a comparative study of the effect on subcutaneous tissue pH of washing with water at 1, 10 and 30 min after injury. After inflicting alkaline injury, the subcutaneous tissue pH reached its peak value at the 32nd minute and had not recovered to the pre-experimental level by the 90th minute. The peak pH values of the 1-, 10- and 30-min delays before washing groups were 7.97, 10.57 and 12.17, respectively. When washing was started within 1 min of injury the tissue pH values did not exceed 8.00. Washing had virtually no effect on lowering the raised pH levels when the delay between injury and the start of washing was 10 and 30 min.