An Electrometric Study of the Healing Wound in Man *

It has been shown that the immediate reaction to injury and the subsequent reparative process, as induced by an incised wound and measured by its tensile strength, always occur in a consistent manner. Expressed graphically, a characteristic curve results resembling that of growth under many other circumstances. The phase in which the exudative reaction is predominant appears in this curve as a "lag period" of some four days, during which there is no material increase in tensile strength. This is followed by the proliferative phase, histologically marked by a rapid increase of fibroblasts, with increase in tensile strength which toward the 10th day causes the curve to become asymptotic. Moreover, it has been found that this expression of growth in the healing wound is surprisingly constant in a given species of animal under most circumstances, and also when several species are compared.7 8 This suggests that the reaction to injury as seen in a healing wound is a fundamental and constant biological phenomenon, as essential to the persistence of the species as are the processes of metabolism and reproduction. However, for obvious reasons, it has been technically impossible in man to study the healing wound using tensile strength as a measureable factor, and quite properly one may question the validity of the application to man of the findings obtained in other species. Fortunately, a method has been devised by Burr, Lane, and Nims5 for determining electric potentials which is applicable to the study of the healing wound. It was shown that in the guinea-pig changes in voltage gradients correspond to changes in tensile strength.2 In one instance of altered healing, that occurring in a vitamin C deficiency, similar deviations from the normal curve of the healing wound were observed. Inasmuch as the electric potentials could be readily ascertained in man having uncomplicated