Circulatory, hypoxemic or traumatic arrest claims an estimated 350,000 lives per year in the United States accounting for almost 15% of all deaths. Circulatory, hypoxemic, or traumatic arrests result in whole-body ischemia, most significantly global cerebral ischemia. Brain cells die when they no longer receive oxygen and nutrients from the blood. Because cerebral blood flow is inadequate during CPR, the likelihood of neurologically intact survival diminishes rapidly with time. Irreversible brain damage begins to occur within 4 to 5 minutes of cardiac arrest if there is no intervention. Restoration of circulation after 5 to 20 minutes of ischemia is accompanied by variable degrees of neurologic damage. BioPhyZica has developed a treatment, known as HES-Z + VitC for treating capillary leak, edema, and reperfusion injury. The hydroxyethyl starch component provides a biophysical action of sealing at the enlarged capillary endothelial gaps (pores) that develop with increased capillary permeability after arrest, while the antioxidant enhances the overall efficacy by reducing reperfusion injury. During Phase I, BioPhyZica and the Medical College of Wisconsin will demonstrate proof of concept by using an animal model of global cerebral ischemia to demonstrate that treatment with HES-Z + VitC will reduce mortality and neurological deficit.