A new method for the objective evaluation of postoperative pain

Pain recognition, registration, and evaluation constitute fundamental problems of pain therapy. The only presently available method that allows for objective pain evaluation is the SCA (skin conductance algesimeter) method. In this method, skin conductance is the measurement of sympathetic nervous system activation caused by a pain stimulus. The activation of the sympathetic fibers that innervate sweat glands induces a release of the contents of these glands and a concurrent decrease in skin resistance and an increase in skin conductance. The presented method exhibits quick reaction to pain stimuli and does not depend on hemodynamic changes, temperature, breathing, neuromuscular blockade, catecholamine administration, or blood volume changes. It may be used in various fields of medicine in which severe pain and its objectification are phenomena that significantly influence the treatment's progress.