If digital pressure does not stop the bleeding and the wound is in one of the junctional regions of the body such as the groins, axillae, or neck, there is a very big problem, potentially CATASTROPHIC TROUBLE. The fundamental challenge is that tourniquets cannot be effectively applied in these challenging anatomic areas. In a care under fire setting, the best and potentially only option will be for the casualty or potential caregivers to move from the immediate danger zone to some cover as any intervention will be complex, time-consuming, and resource-consuming. Complex mechanical compressive devices either of the groin itself or the distal aorta are potentially available but require time, experience, and great mechanical pressure to be effective. Wound clamping is another option, that may even be self-applied, but does risk the simple conversion of external bleeding to internal bleeding with an expanding hematoma. Simplistically, any bleeding control is better than none. Potentially other increasingly elegant solutions are to pack the junctional wound with anything immediately available. From an optimistic perspective, the more hemostatic the packing, the better, but anything is better than nothing. The science tells us that holding pressure on this packed wound for 3 min is as effective as applying a wound clamp to contain the packing material. If the environment is hostile or other pressing tasks/duties/casualties require attention, then wound clamping may have an obvious advantage. An option that should never be forgotten if you have one is balloon catheter tamponade. If someone is exsanguinating, then inserting a balloon into the wound and inflating it may be lifesaving and permit safeextraction. In such cases this may be a bridge to definitive care, or it may be definitive if bleeding has ceased after 24 h when balloons are deflated in some experienced centers.

Once the casualty is removed from immediate danger and it is safe for caregivers to interact, it may be appropriate to bring remote portable point-of-care (POC) ultrasound to bear. Of all the technological medical advances of the last decade, ultrasound technology has been among the most disruptive in emergency care. Most if not all resuscitations now incorporate POC ultrasound, and this modality is increasingly likely to be in the hands of responders in prehospital and extreme environments. Thus, paramedical responders are increasingly being trained to utilize ultrasound in the field with or without real-time medical oversight. Thus, prehospital diagnoses of exsanguination into the pleural and peritoneal cavities should typically be recognized earlier, as should pericardial fluid, potentially directing transport, triage, and even interventions in prehospital environments. A more likely scenario with real-time telemedical/tele-ultrasound mentoring guidance is the actual detection of the bleeding site with Doppler-guided ultrasound and, once identified, evaluating the effective physical compression of this hemorrhage.

Realistically massive intracavitary hemorrhage in a tactical or extreme environment is probably going to be lethal, and all involved should share their last emotions freely and with as many tears as are appropriate. Thus, major noncompressible torso hemorrhage in prehospital environment of any kind is at best TREMENDOUS TROUBLE and not unlikely to be CATASTROPHIC TROUBLE. In a “simpler, safer” prehospital environment, the responders should simply “drive fast” as there are no helpful interventions in the prehospital arena for massive intracavitary hemorrhage. An unknown quandary concerns the issue of concomitant head injury as hypotension has been shown to generate far worse outcomes, yet prehospital fluid resuscitation in the fact on of ongoing hemorrhage propagates coagulopathies, continued bleeding, and inflammation. Thus, the prehospital solution may again be to simply “drive faster.” In other words, gasoline is your most important resuscitation fluid .

While beyond the scope of this chapter, the hemostatic and homeostatic capabilities of the human body are simply stupendous and have all too often been discounted by physicians. It is remarkable how natural hemostasis will control massive bleeding especially after a period of hypotension (i.e., allowing initial clot stabilization). Thus, while the mechanism of action remains unknown, we do adhere to current guidelines concerning admission of tranexamic acid for prevention of hyper-fibrinolysis. We also support the philosophy of not over-resuscitating with fluids. If a casualty is conscious or has a radial pulse, we do not initiate intravenous fluids. If any casualty does NOT have a radial pulse, we immediately respond with the recognition that patients in this subcategory possess a markedly increased risk of mortality. All should recognize that while profoundly important, hypotension is a poorly measured variable. While this is the single most important factor we use to guide activation responses, prehospital blood pressure measurement is an absolutely inexact science with 50% accuracy (akin to flipping a coin). Thus, if system efficiencies can be attained, more accurate prehospital identification of truly “sick” hypotensive patients is required, which may in the future involve POC lactate testing or various derivations of near-infrared spectroscopy.