J B Bridenstine1, J F Dolezal. 1. Department of Dermatology, University of Pittsburgh Medical Center, PA 15213.
Abstract
BACKGROUND: Chemical peeling using trichloroacetic acid (TCA) is a popular and long utilized procedure in dermatology and cosmetic surgery. OBJECTIVE: To determine the actual concentration of TCA in four disparate methods of preparation of solutions, expressed in the standard pharmaceutical method of weight to volume (wt/vol). METHODS: Method I was wt/vol, method II was weight to weight (wt/wt), method III was grams of TCA added to 100 cc water, and method IV was the usage of saturated TCA, and calling it 100%, then making appropriate dilutions. The amounts of TCA in each solution for methods II, III, and IV were converted, by calculation, to the wt/vol method. RESULTS: The relative concentrations of TCA, ranked by the wt/vol pharmaceutical standard, showed that from strongest to weakest: method IV > method II > method I > method III. CONCLUSIONS: Tremendous variations were found in the relative concentrations of TCA in these solutions. To avoid mishaps and complications, the wt/vol method should be used.
BACKGROUND: Chemical peeling using trichloroacetic acid (TCA) is a popular and long utilized procedure in dermatology and cosmetic surgery. OBJECTIVE: To determine the actual concentration of TCA in four disparate methods of preparation of solutions, expressed in the standard pharmaceutical method of weight to volume (wt/vol). METHODS: Method I was wt/vol, method II was weight to weight (wt/wt), method III was grams of TCA added to 100 cc water, and method IV was the usage of saturated TCA, and calling it 100%, then making appropriate dilutions. The amounts of TCA in each solution for methods II, III, and IV were converted, by calculation, to the wt/vol method. RESULTS: The relative concentrations of TCA, ranked by the wt/vol pharmaceutical standard, showed that from strongest to weakest: method IV > method II > method I > method III. CONCLUSIONS: Tremendous variations were found in the relative concentrations of TCA in these solutions. To avoid mishaps and complications, the wt/vol method should be used.