Meet the BSOS Team

Dr. Patrick Walker is a trauma and critical care surgeon at Walter Reed National Military Medical Center and the Program Director of the Battlefield Shock and Organ Support (BSOS) Program at the Uniformed Services University. A graduate of the United States Military Academy at West Point and Emory University School of Medicine, Dr. Walker is an active-duty U.S. Army officer.

Dr. Walker’s clinical and research efforts are driven by an unwavering commitment to America’s service members who come in harm’s way. He advances trauma and resuscitation science across the continuum of care—from the point of injury to definitive hospital recovery—with a singular goal: to maximize battlefield survivability. Leading a multidisciplinary translational research platform, he integrates large‑animal modeling, novel devices and therapeutics, and computational physiology to forge field‑ready solutions that preserve the fighting strength of our Nation’s forces while benefiting civilian trauma care.

Under his leadership, BSOS serves as a national hub for trauma innovation, integrating combat-relevant physiology with emerging therapeutic strategies and accelerating their path from bench to battlefield. Dr. Walker collaborates closely with DoD stakeholders, academic partners, and industry to deliver advances that empower military medical personnel to save lives in the crucible of combat–ensuring that every service member has the best chance to return home.

Dr. David Burmeister is a translational research physiologist and a Professor of Medicine and Surgery at USUHS, serving as the Scientific Director of the Battlefield Shock and Organ Support (BSOS) Program. His research centers on the body's response to trauma, with a focus on mitochondrial involvement in hemorrhagic shock, ischemia‑reperfusion injury (IRI), as well as the impact of fluid resuscitation on burn pathophysiology. He has a keen interest in the role of the gut in critical illness, to include the influence of the microbiome on recovery pathways.

Dr. Burmeister’s early training included a PhD in Physiology and Pharmacology from Wake Forest where he studied endogenous regeneration of the bladder after surgical trauma in the rat. He then embarked on a postdoctoral fellowship at the US Army Institute for Surgical Research, where he developed porcine models of burn wound healing, as well as resuscitation and critical care. His work consistently emphasizes clinically relevant, large‑animal models that bridge bench and battlefield medicine. Notable recent contributions include investigations in burn‑related coagulopathy, arterial waveform monitoring during resuscitation, and the integration of physiological and biochemical methods to evaluate therapeutic strategies.

In his capacity as Scientific Director of BSOS, Dr. Burmeister provides strategic scientific leadership across a portfolio of translational animal studies designed to optimize interventions for military and civilian trauma care. He integrates experimental physiology with cutting‑edge analytics, ensuring scientific rigor, reproducibility, and operational relevance in models of systemic inflammation and recovery.

Dr. Jonathan Morrison is a vascular surgeon-scientist and the Deputy Program Director of the Battlefield Shock and Organ Support (BSOS) Program at the Uniformed Services University. With a career spanning both the British Army and leading academic institutions, Dr. Morrison brings deep expertise in vascular trauma, ischemia-reperfusion injury, and endovascular innovation to BSOS’s translational mission.

He completed his medical training at the University of Edinburgh and earned a PhD in Surgery through collaborative work at the University of Glasgow and the U.S. Army Institute of Surgical Research. Following surgical training and multiple deployments to Iraq and Afghanistan, he held academic appointments at the R Adams Cowley Shock Trauma Center and now serves as Associate Professor of Surgery at Mayo Clinic, where he is also Director of Endovascular Innovation.

Dr. Morrison’s research focuses on the development and evaluation of advanced therapies for hemorrhagic shock and vascular injury using clinically relevant large-animal models. He has authored more than 200 peer-reviewed publications and played key leadership roles in the design and oversight of multicenter clinical trials, including REBOA-related investigations and vascular graft innovations. At BSOS, he helps guide scientific strategy, model development, and regulatory translation, advancing technologies with dual-use applicability across military and civilian care settings.

Dr. JT Green is an active-duty U.S. Army cardiologist and physician-scientist at Walter Reed National Military Medical Center, where he also serves as the Director of Modeling for the Battlefield Shock and Organ Support (BSOS) Program at the Uniformed Services University. His research centers on mechanistic and multiscale modeling of cardiac physiology in trauma and critical illness, with a particular emphasis on shock, ischemia-reperfusion injury, and resuscitation.

Dr. Green leads BSOS’s efforts in digital twin development, applying multiscale modeling techniques to simulate cardiac behavior during trauma, hemorrhagic shock, and extracorporeal resuscitation. His team has successfully developed a functioning, organ-level in silico model of the heart, capable of integrating electrophysiologic, metabolic, and mitochondrial domains. These models are used to better understand the complex dynamics of cardiac recovery and inform the design of precision-based interventions.

Through this work, Dr. Green is advancing the BSOS mission to bring predictive modeling tools into translational research and clinical decision-making, accelerating innovation across both military and civilian trauma care systems.

Dr. Woo Do is a pediatric and trauma surgeon and the Director of Education for the Battlefield Shock and Organ Support (BSOS) Program at the Uniformed Services University. He also serves as Chief of Pediatric Surgery at Walter Reed National Military Medical Center. A graduate of West Point and Harvard Medical School, Dr. Do completed his general surgery residency at Madigan Army Medical Center and his fellowship in pediatric surgery at Boston Children’s Hospital.

Dr. Do’s clinical and research work bridges pediatric and battlefield trauma, with a focus on extracorporeal life support, hemorrhage control, and survivability in austere environments. His translational research includes preclinical modeling of hemorrhagic shock and resuscitative strategies, with the goal of redefining what injuries are survivable in pediatric and combat populations. As Director of Education, he leads efforts to mentor the next generation of military surgeon-scientists, integrating surgical training with operational readiness and translational innovation.