 The Army Medical Corps' function of conserving the fighting strength is supported at the Army Medical Service School, Brook Army Medical Center, by training newly inducted military surgeons in the principles and practices of traumatic surgery incident to combat. Unlike the ancient adage of Hippocrates, he who would be a surgeon should join the army and follow it. Few surgeons in our modern age have had any experience in combat surgery, and not many have had comprehensive training in traumatic surgery. How then can the principles and practices of combat surgery be taught short of open war? A method here to foreutilize by the armed forces has been a didactic one in which a surgeon with combat experience lectured and used training aids to present the subject. An obvious shortcoming of this spectator type learning is lack of teaching value inherent in lack of participation by the students. As is well known, active participation by the student in the learning of surgical techniques is a far faster and more thorough method. Here at the Army Medical Service School, we resorted to the laboratory to devise a new method of teaching combat surgery, whereby all students can participate in actual surgery in a field type surgical installation under the supervision of combat trained personnel. Under controlled conditions in the laboratory, any type of regional wound can be produced and treated in a manner consistent with current surgical doctrine. The laboratory also permits an expanding program of experimentation to test current surgical doctrine and to devise new principles and practices which, with proven success, are recommended for future adoption. Our laboratory is a mobile Army surgical hospital in Tentage, constructed in the field so that all equipment, supplies, and facilities are the same as utilized in the combat zone. The operating section is modified in such a manner that additional operating equipment may be installed to accommodate the large groups of participating students. Erected in front of the hospital are stands where all students may be seated to watch a surgical demonstration which precedes the laboratory exercise. In front of the stands, a mirror is so arranged that an indirect view of the surgical demonstration is obtained by reflection. This ensures that all phases of the demonstration are observable without obstruction by the operator's hands, equipment in the vicinity, or by the heads of other students. For the present, the maximum emphasis is placed on this installation being a teaching laboratory, not an experimental one. However, changes can be made so that experimentation and teaching can be carried out concurrently with only minor modifications in existing facilities and equipment. The wounding pit is constructed a safe distance away from the laboratory and meets all the requirements of Army ordinance regulations. A wounding frame for strapping the animal in a standing position provides controlled wounding. The exercise begins with an orientation in which is outlined the role of the students and the objectives of the procedures to be performed. These medical officers are a representative cross-section of many medical schools in the United States and as such represent current teaching doctrine on the surgery of trauma. Class after class of these medical officers exemplify the fact that the principles of adequate debriefment have received little or no emphasis either in their medical school or post-graduate training. And yet, this is the single most widely used surgical procedure in the combat zone. On this basis, it was felt that our new teaching method should be applied to debriefment first and later broadened to include many other practical exercises in emergency medical treatment and emergency surgery. It's extremely important that you learn the principles and practices of debriefment for one reason if no other. And that is, debriefment surgery in the combat zone is the one operative procedure which is performed on all combat casualty. There are about 162 of you in this audience. Prior to putting on or prior to you participating in the practical exercise, we will put on a demonstration for you of how the debriefment should be accomplished. At the wounding pit, the demonstration animal is anesthetized, utilizing intravenous nebutol in an anterior jugular vein. After wounding, pressure dressings are applied. At the demonstration table, the animal is prepared for surgery. A sepsis is practiced throughout the demonstration. The preparation of the skin of the animal, as you noticed a moment ago, will consist of methylate. In your draping, be sure that you drape a wide enough area to allow for an incision big enough to encompass all of the necrotic tissue. Can all of you see this wound? This wound apparently is the result of the missile having traveled through both extremities and this apparently is the wound of exit. It's a large jagged wound, certainly not the type of wound which would have been inflicted by the missile striking the extremity nose off. Now you'll recall that the first principle in performing an adequate debriefment is to make a long incision in the long axis of the extremity. Should be through the skin, down to the fascia, you will find that only a minimal amount of skin must be excised. Skin is normally resistant to necrosis by the missile as it passes through. You can recognize the area of necrosis involving the skin by its appearance. In any event, only a minimal amount of skin must be excised. The more skin you excise, the more difficult it will become at a later date for a necessary secondary closure to be performed. As soon as the skin and fascia is open, you can recognize the missile tracked by the necrotic tissue which you'll find in the depths of the wound. Typically, I think all of you can see this. All of that muscle must be excised. There are four considerations in the excision of that muscle. Those are change in color, lack of contractility, lack of bleeding when you cut it, and the mushy consistency of the muscle. Right now, the changes are not very marked because the animal was wounded no more than five to ten minutes ago. In any event, you start excising your muscle until you encounter normal muscle. Now, here's a good area showing the change in color and change in consistency and absence of contractility. Can you see that? Can you see that it does not contract? Well, you'll recognize it yourself when you see it on your own animal. When you run into an area in which contraction starts to occur, or where bleeding occurs, you recognize that you've gone beyond the area which has been rendered necrotic by the missile. Now, notice how much larger is the ultimate wound as compared with the appearance and the size of the wound before we started. Now, those of you who are close enough can see that we already have a relatively clean missile track. The muscle now responds to pinching and bleeds when cut and is of a normal color. Now, after you have debrided as much of the extremity as you can to breed, take your towels off, take off your towel clips, turn the leg over, and complete your debride mon from the other side. And again, on this other side, you follow through the same principles that you did on the first side. Notice how much smaller is the wound of entrance at this point as compared with the wound of exit which you saw on the other side. Now, when you do your debride mon, we'd like to have you have one of us check it to be certain of the adequacy of debride mon. Section 1, to get down the wounding pitch, you can pick up your animals there. Here is where actual student participation begins. Students work in groups of five per animal. This team consists of one chief surgeon, one assistant surgeon, one scrub nurse, one table assistant, and one anesthesiologist. Asepsis is practiced with regard to the hands and gloves of the operating team, equipment, and drapes. All techniques employed are those used in a surgical hospital in the combat zone. Now, for the first time, these newly inducted medical officers are performing surgery in a field type installation and can acquaint themselves with the equipment and facilities available. It is not intended to make finished combat surgeons of these students. Our purpose is twofold. One, to teach a familiarity with those principles and practices which, if well learned on the laboratory animal, may later be responsible for saving life and limb, thus decreasing morbidity and mortality in combat. And two, to demonstrate on living animals the effects of weapons of warfare. We find that students are extremely grateful for the opportunity to learn the principles and techniques of what they feel is an neglected field in the average medical school. They leave here with the feeling that, having participated in one Debreed Mon, they are certainly better qualified to perform that first one in combat or in a similar situation. All work by the students is supervised, and before an experiment is terminated, the wound is surveyed to ascertain completeness of the procedure and adherence to the advocated techniques. This new concept of teaching combat surgery demonstrates that, now for the first time, surgeons can practice acceptable techniques on casualties who respond to their ministrations. Now, for the first time, we can modify combat surgical techniques without being engaged in war. Here, for the first time, is an opportunity to experiment with many time-honored adages concerning the management of battle casualties so that changes can be made, not during the chaos of war, but in the controlled atmosphere of the laboratory. Now, for the first time, principles and techniques of battle casualties surgery may be modified not because of increased human morbidity, but by carefully controlled wounding experiments on laboratory animals. Experience with this laboratory indicates that its basic organizational concept permits large numbers of surgeons to perform wound surgery simultaneously, and thereby lends itself especially well to modification for the surgical management of mass casualties. With increasing emphasis on civilian defense and with tremendous interest among physicians on the management of victims of trauma, this method of active participation by large numbers of surgeons simultaneously may give a preview of the management of mass casualties in any future disaster, civilian or military.