3—
Combat Medicine

Provide for significant advances in the development and application of medical technologies for reducing combat casualties and deaths.

THE COMBAT MEDICAL ENVIRONMENT

When it is required, combat care is needed immediately, often in remote locations and under the most stressful conditions. During small contingency actions—in the Lebanon- and Somalia-type operations that are likely to occur in the future and allow little public tolerance for casualties—immediate, high-quality combat care is required. A sophisticated combat medical capability has become a necessary part of military missions with diplomatic and political consequences. This continually evolving role places increased pressure on the Navy to be able to respond to all contingency operations with immediate combat care. The current Gulf War medical debate illustrates how new weapons (chemical and biological) may be available to almost every adversary nation, and the Navy should be prepared to respond as new combat treatments are required. Combat care—particularly urgent battlefield care—should be given priority in DOD and Navy Department medical investments and in new technology development. Medical career patterns in the Navy should be modified to emphasize the importance of combat medicine capability and experience.

The first defense against the effects of hostile fire, disease, and lethal environmental agents is a continuous process of maintaining a healthy, physically fit, and psychologically resilient force. Major advances in physiological preparedness are anticipated. Today, the Navy relies on exercise, diet, routine physicals,



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3— Combat Medicine Provide for significant advances in the development and application of medical technologies for reducing combat casualties and deaths. THE COMBAT MEDICAL ENVIRONMENT When it is required, combat care is needed immediately, often in remote locations and under the most stressful conditions. During small contingency actions—in the Lebanon- and Somalia-type operations that are likely to occur in the future and allow little public tolerance for casualties—immediate, high-quality combat care is required. A sophisticated combat medical capability has become a necessary part of military missions with diplomatic and political consequences. This continually evolving role places increased pressure on the Navy to be able to respond to all contingency operations with immediate combat care. The current Gulf War medical debate illustrates how new weapons (chemical and biological) may be available to almost every adversary nation, and the Navy should be prepared to respond as new combat treatments are required. Combat care—particularly urgent battlefield care—should be given priority in DOD and Navy Department medical investments and in new technology development. Medical career patterns in the Navy should be modified to emphasize the importance of combat medicine capability and experience. The first defense against the effects of hostile fire, disease, and lethal environmental agents is a continuous process of maintaining a healthy, physically fit, and psychologically resilient force. Major advances in physiological preparedness are anticipated. Today, the Navy relies on exercise, diet, routine physicals,

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and after-the-fact urgent medical care. By 2035, it should be possible to have full wellness programs with continual monitoring of many physiological and psychological processes, job-specific performance enhancers, and genetic testing for physiological and behavioral strengths and vulnerabilities. Moreover, advances in biomedical and behavioral sciences may salvage a significant number of persons who are currently excluded from military service because of physical or psychological problems. In combat, the process of medical prevention and treatment will continue with the aid of special devices and procedures that have been designed to enhance protection from, or provide immediate treatment for, injuries resulting from battlefield hazards. These hazards include direct enemy action as well as dangers imposed by the hostile environment. It is important to have a medical system in place through telemedicine that enables the connection of remote sites (ships, battlefield) to medical facilities located in the continental United States (CONUS). Naval operations in 2035 will pose new types of antipersonnel threats combined with the familiar threats of explosive devices and projectiles. The new threats will include chemical and biological warfare agents delivered by artillery, bombs, rockets, or missiles, and directed-energy weapons such as lasers, high-powered microwaves, radio-frequency waves, and other forms of nonionizing as well as ionizing radiation. Also likely is the addition of environmental and geographical extremes associated with contingency operations that require U.S. forces to deploy to remote areas of the world. Fighting in these areas carries with it the added significant threat of infectious diseases, a special form of environmental hazard. Finally, future operations will expose naval forces to extraordinary levels of psychological stress resulting from highly accurate and lethal weapons; silent and deadly chemical or biological agents; equally silent and dangerous directed-energy devices; sustained operations; increased dispersion and isolation of small units; and the uncertainty of contingency operations in remote areas. PROTECTION AND PREVENTION One major concern of military medical departments is specialized preventive measures. These include drugs and vaccines to protect our forces against nuclear, chemical, and biological agents; physiological monitoring of body temperature, hydration, and alertness; specially designed ensembles for protection from projectiles, directed-energy devices, and chemical and biological agents; and psychological aids, such as land navigation and local communication devices that enhance security and provide information regarding available support. The Department of the Navy should seek to integrate lightweight body armor into its combat forces so that each sailor or marine within a group will be wearing unencumbering body armor with an integrated personal status monitor. This will provide real-time updates of combat personnel status.

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By 2035, U.S. naval forces should be able to provide significantly enhanced protection for individuals in all combat situations. Although the United States will face more varied biological and chemical threats, it should be possible to counter those threats with genetically engineered solutions and better antidotes. The ability to deploy effective countermeasures further depends on an accurate assessment of the threat, and a comprehensive threat assessment capability should be a critical element in the Navy's suite of preventive and protective countermeasure capabilities. The Department of the Navy has an opportunity to leverage ongoing advances in protein analysis and chemical and biological assay sensors (e.g., biosensors on a chip) by supporting the development of these technologies for Navy- and Marine Corps-specific applications. In particular, technology development will be required to realize the reliable performance of these devices under combat conditions. The expected availability of a complete DNA analysis for individual service personnel will facilitate the design of individually tailored countermeasures to anticipated chemical and biological assaults. By 2035, the United States will be able to replace today's cumbersome and marginally effective mission-oriented protection posture (MOPP) gear, flak jackets, and helmets with flame-retardant environmental suits and lighter, smart body armor. Eye shields will be greatly improved to counter the anticipated use of more blast, high-energy particle, and burn injuries in the future. Mechanical and electronic devices for blocking or canceling energy that affects the visual or auditory systems will also be available to protect individuals from a variety of high-energy sources (blast, laser, microwave, vibration, and sound energies). If better information is available on the potential threats faced by U.S. forces, appropriate modification of body armor and other forms of protection for individuals should be possible through the use of adaptive information systems. Physical protection that includes impregnable uniforms and protective masks is essential, but advanced technology threats will require the application of even more advanced technology to counter them. New protective technologies will include fabrics with selectively permeable membranes that exclude threat agents but allow individuals to hear, see, move, breathe, and perspire normally. A second, perhaps more effective, approach for some threat agents is the administration of physiologically protective drugs—either immunological or passive scavengers—that block or neutralize the adverse effects of entire classes of threat agents. Protective clothing, or body armor, will be able to provide medical intervention by administering these physiologically protective agents on demand or as indicated by sensors built into the clothing. It will also be able to warm or chill the wearer, inject hemostatic agents, and apply fiber-type glue to wounds as needed. Finally, it will be able to bear weight and supplement some body movement and large muscle function, as needed. The Navy and Marine Corps have a direct interest in the availability of these capabilities, but little research funding is currently allocated to their development. The Navy Department should consider treating the development of these capabilities as a research priority.

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CASUALTY ASSESSMENT, CARE, AND EVACUATION Combat inevitably causes casualties that require immediate assessment and sophisticated medical care of an injury at far-forward positions. By 2035, physiological surveillance will be greatly enhanced through the use of sensors and personal status monitors. The use of telemedical technologies will allow medical and paramedical personnel to perform many more of the procedures required within the first 30 minutes of injury. Telemedicine has multiple levels from CD-based to Internet store and forward (non-real time) to telesurgery. It should be possible to provide just-in-time surgery anywhere and anytime. The capability to provide effective and immediate treatment on the battlefield at or near the site where injury occurs will save lives. This capability will become increasingly important to ensuring rapid recovery that serves to minimize mission impact and avoid permanent disability. As discussed above, naval operations will involve dispersed, independent units located far from friendly medical care facilities. The time, people, and facilities available to care for casualties will be severely limited. This situation will be particularly serious given the narrow window of opportunity available to care for serious wounds and injuries. About 90 percent of deaths in military operations occur in the first 30 minutes, when often the only care available comes from the casualty victim him- or herself, a buddy, or a corpsman. Immediate care of casualties requires precise information on the location and physiological status of wounded or otherwise incapacitated personnel. This information is essential if medical care is to be effective in minimizing losses; the same information is also critical for timely command decisions regarding the status of engaged forces for continued operations or the need for replacements or unit reconstitution. In the past, the Department of the Navy has used a medical care approach based on echelons of care. In the future, it will use an approach that defines levels of care in terms of time frames ranging from hours to days. This will allow improved use of resources and concentration on clinical capabilities. Today, the Navy and Marine Corps medical units depend on line of sight, personnel accounting, and radio communications. By 2035, all individuals are likely to have personal status monitors that provide both precise location and physiological assessment information. In addition to the individual's voice channel, the monitor inputs will include indicators of heart rate, respiration, body temperature, skin resistance, arterial blood pressure, stress, and alertness. In the past, the military has actually developed personal status monitors, but their deployment was not continued due to insufficient testing. The availability of a personal status monitor would add valuable capability to both current and future operations. The fluidity and rapidity of military action and the dispersed character of the future battlefield will influence the type and location of facilities for medical treatment. The emphasis will be on compact, lightweight, highly mobile medical

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facilities for diagnosis and forward medical treatment and on extensive digital signal processing and computer utilization, including medical databases. Among the needs of the combat medical system are field medical devices; new battle dressings; filter absorption systems; on-site oxygen production or conversion; improved venous access devices; improved peripheral perfusion and ischemia monitoring; and self-calibrating in vivo blood gas, pH, and electrolyte monitors. MEDICAL TECHNOLOGY Many promising technologies under development or on the horizon could help improve combat and battlefield care. Although many of the emerging technologies have a dual use for both combat and civilian medical practice, some of them should be pushed for early evaluation for combat medicine. Among the capabilities needed are medical databases that record an individual's medical history and are coupled to a monitoring system. The sailor or marine should have a medical history and patient-specific virtual human body model built into the memory of his or her suit and entered in the medical information system. Already available for use are new battle dressings in the form of self-contained antibacterial gels for application to burned skin. They provide protection from further damage to the skin as well as relief from pain. The dressings are designed so that they expand with moisture derived from the air when the packet containing them is opened. They can be incorporated directly into the body armor and released automatically. Both filter absorption systems and on-site oxygen production will be important to the combat medical system. The absorption systems will be used for on-site production of sterile fluids, including intravenous fluid. Although on-site oxygen production or conversion is not yet possible, it is anticipated that in the future enhanced technological developments will provide this capability. To reduce the complications of infection, phlebitis, or thrombosis, improved venous access devices will be required. The results of initial trials of one such device have been promising and have shown no adverse effects for test periods of up to two weeks. Problems that have to be resolved relate to the rigidity of a metal needle and to electroplating with the least irritating metal surface. Improved monitoring of peripheral perfusion (blood flow through tissue) and ischemia (localized tissue anemia resulting from obstruction of the inflow of arterial blood) will be used to enhance shock trauma management. Most investigators and experienced clinicians accept a definition of shock as a persistent state of poor peripheral perfusion. Today, evaluations of the severity of shock can be made only on a clinical basis, supplemented with indirect laboratory measurements. By 2035, more direct assessment of peripheral perfusion will be possible. The personal status monitor will be able to provide thermistor-polarographic sensing that combines measurements of temperature (as an index of tissue perfusion) and oxygen tension (as an index of tissue ischemia). The monitor will also

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allow measurement of oxygen tension to be correlated with perfusion. In contrast to the current state of the art (i.e., microbeads used to assess perfusion), the personal status monitor will allow on-line readings to be repeated indefinitely. The personal status monitor will be integrated into the overall health care delivery system. This will allow care providers from the front line to CONUS to better handle medical logistics and decision making. Personal status monitors will also provide self-calibrating in vivo blood gas, pH, and electrolyte measurements. A limitation of current instruments for continuous monitoring of blood gases and pH is their requirement for frequent and recurrent calibration. They are also invasive and require frequent sampling of blood. Current noninvasive instruments are less reliable and depend on cutaneous circulation. These disadvantages will be circumvented by development of a membrane for a disposable intra-arterial device that continuously monitors arterial oxygen pressure, arterial carbon dioxide partial pressure, pH, and electrolytes and requires no laboratory calibration or removal of blood. By the year 2035, these devices might possibly be implanted or swallowed. Mind-machine communication used to control devices for transporting micro-sensors throughout an individual's body may become a significant tool for aiding self-assessment and diagnosis in 2035. Bandaging material that is impregnated with new hemostatic agents and can be inserted into a wound will control most bleeding. The only exception would be hemorrhage from a major vessel, which might require a tourniquet, depending on its location. Often, troublesome bleeding is not from a major vessel but is the continuous, significant hemorrhaging of many smaller vessels. Hemostatic wound dressings combined with small-volume, stable, concentrated oxygen-carrying fluid will also reduce shock in combat casualties. Major hemorrhaging can be stopped with an automatic response from body armor acting as a tourniquet. Robotic-directed catheters based on the patient-specific virtual model can be placed peripherally to stop major vessel bleeding centrally. Monoclonal targeted antibodies can be used for topical therapy of wound infections and burns. By 2035, artificial skin and bone will be available as tissue substitutes to facilitate wound healing, burn control, fracture stabilization, and prevention of permanent disabilities. A combination of synthetic and biological materials that replicates the role of the epidermis makes up membranes that are now in clinical trial. They will certainly improve throughout the next 30 years. Reconstitution of the dermis, based on seeding cells from the patient's skin into the membrane, is currently at the research stage. It appears to replicate normal tissue and significantly reduces contractures. These same techniques offer promise for forming epineural sheaths to guide axonal growth in peripheral nerves and to use in blood vessel prostheses. An alternative approach may involve replication of the patient's own skin cells on the massive scale necessary to produce adequate coverage. This approach can also be used for whole organs or limb replacements, as well. It should also be possible to make better replacements for organs or

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limbs through the use of tissue engineering. Alternatively, it may make sense to stockpile animal organs to be used to replace vital organs just as blood is now stored and made available. Animal organs may be used extensively for this purpose by 2035. Artificial blood vessels may meet the challenges of smaller vessel prostheses. The integrated construction of the prostheses will prevent the complication of fibril shredding that is characteristic of adhesively bonded fibril surface systems. Because the bulk mechanical properties of the graft are determined principally by the solid nonporous substrate, the desired graft compliance may be achievable by simply adjusting substrate thickness. Cultured skin grafts and cultured epidermis for the treatment of massive burn wounds are still a topic of controversy, even though the technique for covering burn wounds with cultured cells has been available since 1984. A recent study, however, demonstrated a significant reduction in both morbidity and mortality in patients suffering from burns on 40 percent or more of their body who were treated with cultured keratinocytes. By 2035, endotoxin vaccines may be available for the treatment of shock to prevent the development of toxins during prolonged severe hypoperfusion of tissues during shock. Recent evidence shows that the toxin in the gut stems from loss of the barrier function in the hypoperfused area. This permits the migration of toxins, or perhaps whole bacteria, across the gut wall and into the circulatory system. Hypoperfusion also damages the reticuloendothelial system and diminishes its protective barrier. Entrance of a toxin or of bacteria into the circulation may be the primary cause of the pulmonary complications or multiorgan system failure responsible for most deaths after prolonged shock. Prevention of these life-threatening consequences of shock will require rapid and adequate restoration of circulatory volume, the use of broad-spectrum antibiotics, and some type of vaccine to neutralize the effects of liberated toxin. Nutrition to protect the liver and the gut barrier function also is a vital area for examination. Various pharmaceutical developments will enhance the combat medical system: Drugs will assist in more rapid recovery from acute stress reactions. Pharmaceutical agents will induce hibernation in casualties to suspend deterioration while patients await definitive diagnosis and treatment. Means will be developed to protect individuals against biological and chemical agents and to detoxify them as needed. Microencapsulated antibiotics with the capability of providing sustained, high local levels and minimal systemic levels of antibiotics will be implanted as needed. Direct administration of drugs by protective suits or remotely by telemedicine will be possible.

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Finally, it will possible to relieve today's heavy reliance on corpsmen to some extent by the greater self-reliance of individuals in diagnosing and treating their injuries and in communicating information about their status and treatment to medical center personnel. Telemedicine systems will be prevalent and will augment the skills and knowledge of medical personnel in the field. These systems will support acutecare decision making by frontline personnel through the use of video capabilities and medical instrumentation that enable communication with medical experts in distant locations. This development will affect the way casualties are handled, the way acute care decisions are made, and the way medical personnel are selected, assigned, and trained. In addition, the professional isolation of service personnel stationed away from academic medical centers can be reduced by offering the face-to-face connectivity, database access, and continuing medical education available from these telemedicine systems. It is unlikely that telemedicine systems, even in 2035, will go so far as to provide sufficient capacity, portability, durability, and, especially, tactical security to allow real-time, on-line telesurgery in an acute-care, field setting. However, use of these systems to support personal status monitoring, trauma care and decision making, threat assessment, and other biomedical applications is likely. The many advantages, including financial, that are presented by the deployment of telemedicine systems are significant. Study of these evolving systems to analyze their development, use, and placement would yield significant returns to the Navy and Marine Corps and should be pursued. The resuscitation technologies described above will be paired with improved equipment and procedures for evacuation. Casualties will be pressure-suited or placed in protective concoons, if necessary, to maintain blood pressure. They may then be evacuated using encapsulated, mobile robotic platforms that provide both environmental protection and physiological monitoring. There will be a continuous care system based on levels of care and a time frame starting in the far forward battlefield with a smart body suit. The injured person will be transferred to a smart structure that will fit into a trauma pod. This pod will be mounted in a mobile land-based operating room (armored ambulance) that can be transported to a mobile airbase operating room for transport back to the next level of care on board ship. These capabilities for treating casualties will be well within the state of the art in 2035. Whether or not they are actually available to naval forces and supported by people who can use them well will depend on the extent to which the Department of the Navy emphasizes combat medical care capabilities—care that can be provided in the first 30 minutes. The Department of the Navy should accelerate and support R&D in combat medicine that focuses on integrated protection and monitoring systems, on at-sea medical systems using telemedical capabilities, and on advanced pharmaceutical products that are effective against new battlefield weapons. Naval combat medi-

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cal capability should be enhanced through the development of a battlefield threat assessment and response system. Development of such a system should include biotechnology R&D focused on improved methods for early detection, identification, and countermeasures to prevent or neutralize the adverse effects of chemical, toxin, or biological threats; to counter nuclear and directed-energy threats; and to reduce the risks from environmental hazards. Timely and effective response to new threats depends on making the knowledge of potential threats and countermeasures available to the combat medical specialist. Finally, and most importantly, the Department of the Navy should place much more emphasis on the pursuit of combat medicine capability in its medical caregivers and should reward those who specialize in combat medicine more fully in accord with its value to our naval forces and naval operations. Innovative military medicine, focused on serving its customer, the combatant, has the potential to become the benchmark for a responsive U.S. health care delivery system. There are important cultural enablers to achieving greater levels of survivability in 2035. They require (1) integration of combat and medical elements in planning, (2) improvements in the requirements process for field medicine, (3) better career paths for combat medical personnel and specialists, (4) dedicated funding for combat medicine, and (5) a specialty that focuses on combat medicine with its own training program. In brief, the Department of the Navy should place additional resources and focus on combat medicine and on the technologies that enhance the effective delivery of medical care anytime and anywhere. In achieving this end, the Navy will substantially improve the care of those most deserving its attention. Moreover, by better ensuring the presence of naval force personnel when and where they are needed, investment in survivability is a major force multiplier. Such investments will be repaid directly in increased force readiness and effectiveness where they are most needed.