An estimated 1.6 million head injury occurs every year in the United States. Traumatic brain injury affects 3 out of every 1000 Americans each year accounting for as many as 60,000 deaths and an estimated 70,000 to 90,000 patients with permanent neurologic disabilities. Despite advances in the treatment of patients with head injuries, traumatic brain injury is the leading cause of death and disability in children, adults in their most productive years, and our soldiers in the military. The economic consequence of these injuries in terms of both lost productivity and the cost of medical care are enormous. While the last two decades of research has resulted in a greater understanding of the physiologic events leading to secondary neuronal injury, advances are needed in the treatment of elevated intracranial pressure and decreased cerebral perfusion secondary brain injury. The applicants recently developed a novel device to decrease intracranial pressure and increase in cerebral perfusion pressures. The new non-invasive device is inserted within a standard respiratory circuit between the patient and a means to ventilate the patient (e.g. mechanical ventilator). It functions by cycling between lowering intrathoracic pressure during the expiratory phase to subatmospheric levels and providing a means to provide positive pressure ventilation. The decrease in intrathoracic pressure, typically to -7 to -9 mmHg, creates a vacuum within the thorax relative to the rest of the body thereby a) enhancing blood return to the heart and consequently increasing cardiac output and blood pressure and b) lowering intracranial pressure thereby increasing cerebral perfusion. Use of the intrathoracic pressure regulator (ITPR) is intended to significantly improve patient outcomes, based upon a unique way to increase in blood flow to the heart and brain. Phase 1 studies, the investigators 1) Established safety and proof of concept of the ITPR device in animals by demonstrating that use of the ITPR in the first hour after a substantial and potentially lethal brain injury helped to maintain metabolic stability of the brain better than standard resuscitation fluid alone;2) Incorporated an intrathoracic pressure vacuum gauge into the ITPR system and begun work on a closed loop system by prototyping a custom digital display interface that tracks important physiological variables like intracranial pressure and intrathoracic pressure and 3) Received 510k clearance of the device. This phase 2 research application proposes to 1) Demonstrate proof of clinical concept that application of the ITPR will result in a decrease in intracranial pressure and an increase in cerebral perfusion pressure in patients with head injury in a neuro-intensive care unit;and 2) Design and prototype an enhanced, variable vacuum version of the ITPR with self-contained vacuum source and power supply for use in the OR and ICU. If a significant clinical benefit is demonstrated in these Phase 2 investigations, the ITPR promises to provide a fundamentally new tool to increase cerebral perfusion and thus reduce morbidity and mortality in patients with increased intracranial pressures, including patients who suffer from traumatic brain injury and stroke. PUBLIC HEALTH RELEVANCE: Despite advances in the treatment of patients with head injuries, traumatic brain injury (TBI) is the leading cause of death and disability in children and adults in their most productive years. It is also a leading cause of morbidity and mortality in the military. An estimated 1.6 million head injury occurs every year in the United States. Traumatic brain injury affects 3 out of every 1000 Americans each year accounting for as many as 60,000 deaths and an estimated 70,000 to 90,000 patients with permanent neurologic disabilities. Despite advances in the treatment of patients with head injuries, traumatic brain injury is the leading cause of death and disability in children, adults in their most productive years, and our soldiers in the military. The economic consequence of these injuries in terms of both lost productivity and the cost of medical care are enormous. While the last two decades of research has resulted in a greater understanding of the physiologic events leading to secondary neuronal injury, advances are needed in the treatment of elevated intracranial pressure and decreased cerebral perfusion secondary brain injury. The applicants recently developed a novel device to decrease intracranial pressure and increase in cerebral perfusion pressures. The new non-invasive device is inserted within a standard respiratory circuit between the patient and a means to ventilate the patient (e.g. mechanical ventilator). It functions by cycling between lowering intrathoracic pressure during the expiratory phase to subatmospheric levels and providing a means to provide positive pressure ventilation. The decrease in intrathoracic pressure, typically to -7 to -9 mmHg, creates a vacuum within the thorax relative to the rest of the body thereby a) enhancing blood return to the heart and consequently increasing cardiac output and blood pressure and b) lowering intracranial pressure thereby increasing cerebral perfusion. The goal of this project is to demonstrate proof of clinical concept in a patient population with elevated intracranial pressures. If a significant clinical benefit is demonstrated in these Phase 2 investigations, the ITPR promises to provide a fundamentally new tool to increase cerebral perfusion and thus reduce morbidity and mortality in patients with increased intracranial pressures, including patients who suffer from traumatic brain injury and stroke.