The conception of many investigators, notably Cannon, Dale, Mann, Erlanger and Gasser, that the primary cause of surgical shock is a loss of blood volume, renders a comparative study of the effects of physical trauma—especially of the abdomen—without hemorrhage, and of hemorrhage without physical trauma, of especial significance, the essential point being to determine what are the primary and what are the secondary factors in the end-results of each. As has been stated in the preceding sections of these studies, the limited space at our disposal prevents specific reference to the work of the many investigators in this field; nor would a review of the literature be appropriate in a presentation, without discussion, of the findings in our own researches. Throughout these studies, however, the literature has been studied, as evidenced by the bibliographic references appearing in previous publications.
Our first separate studies of the effects of hemorrhage unassociated with