Potential Resuscitation Strategies for Treatment of Hemorrhagic Shock

摘要

Exsanguination is the major cause of death on the battlefield. Of those who die on the battlefield, it is estimated that 20% could be salvaged before exsanguination if provided with immediate care. Upon arrival at the scene, a First Responder must immediately control bleeding. If the injury is on the body surface or extremity and compressible, direct pressure or a tourniquet is current standard treatment for attempting adequate hemostasis. Ideally, a hemostatic dressing would circumvent the tourniquet by staunching severe bleeding, and require no further attention by the medic. For suspected non- compressible bleeding, for which there is currently no adequate treatment, the ideal would be an intravenous resuscitation solution containing a substance that enhances clotting or clot stability only at the bleeding sites. Once bleeding is controlled, the next step is to resuscitate the patient. In the battlefield, if hemostasis is not assured, aggressive resuscitation may dislodge the clot and exacerbate bleeding; aggressive resuscitation also requires large volumes of fluid, presenting a logistical difficulty. An improved strategy would resuscitate only to the point at which survival was assured and would not cause further bleeding even during the predicted prolonged evacuations that may occur in an urban warfare environment. This article gives an overview of recent work using a severe hemorrhagic shock animal model with an arterial injury on (1) the point at which blood pressure dislodges the thrombus (the pop-clot pressure); (2) an injectable clot stabilizer (fix-a-leak) that is a naturally occurring factor in the clotting cascade (human recombinant Factor VIIa); and (3) the maximum time up to 24 hours for hypotensive resuscitation below the pop-the-clot pressure (how low for how long).