It is accepted that so long as men and women are sent into combat, some will be wounded or killed. In order to minimize those that are killed, efforts must be made to optimize medical treatment for those who are not fatally wounded. The nature of warfare is changing. The pattern of wounding is changing as well. However, what remains constant is the need to provide effective treatment as soon as possible. In war, it means acting at the level of the battlefield. To be effective demands new approaches to diagnosis and treatment. Novel diagnostic tools are needed to identify location of foreign bodies, determine extents of injury, monitor vital signs, and ascertain adequacy of resuscitation. Treatment devices that can provide hemostasis, support organ perfusion, stabilize limbs and neck and relieve a pneumothorax are lacking. Our young soldiers of tomorrow need solutions to their injuries today.

Body-worn noninvasive physilogical sensors are needed to continuously monitor soldiers for hemorrhage and to provide real-time information for minimally skilled medics to treat the injured. In the hospital intramucosal pH_i of the gut is used to monitor shock and its treatment. We hypothesize that abdominal wall muscle (AWM) pH can be measured noninvasively using near infrared (NIR) spectroscopy and partial least squares analysis (PLS) and will correlate with pH_i. METHODS: AWM pH was measured with microelectrodes and gastric pH_i was measured with a tonometric catheter simultaneously while NIR spectra were collected using prototype LED spectrometers placed on the pig's flanks. Animals were subject to hemorrhagic shock at 45 mm Hg for 45 minutes, then resuscitated with blood and lactated ringers. Relationships between electrode pH, pH_i and NIR spectra were developed using PLS with cross validation. RESULTS: NIR spectral changes noninvasively acquired through the skin were shown to be from the muscle, not from changes in skin blood flow. Trending ability (R²) model accuracy (RMSD), and relative error were calculated for individual pigs. Using electrode pH as the reference, average R² was 0.88 with a predicted accuracy of 0.17 pH units, a 9.3% relative error. Slightly degraded results were observed when pH_i was used as a reference. CONCLUSIONS: NIR measurement of tissue pH can be used to noninvasively monitor for shock and guide its treatment in a swine model. These measurements correlate with gastric pH_i, a clinically accepted measure of shock, providing an approach to develop similar methodology for humans.

A novel method for identifying and localizing brain hemorrhage is presented. This method uses electromagnetic waves in the microwave and RF region and a modified algorithm previously used for the estimation of the angle of arrival of radar signals. Results are presented applying this device for detecting epidural and intracerebroventricular hemorrhages in anesthetized pig.

Assessing the medical condition of battlefield personnel requires the development of rapid, portable biological diagnostic assays for a wide variety of antigens and enzymes. Ideally, such an assay would be inexpensive, small, and require no added reagents while maintaining the sensitivity and accuracy of laboratory-based assays. In this work, a microelectromechanical (MEMS) based biological assay sensor is presented which is expected to meet the above requirements. The sensor is a thin silicon membrane resonator (SMR) which registers a decrease in resonant frequency when mass is adsorbed onto its surface. By coating the sensor surface with a monolayer of antibody, for example, we have detected the corresponding antigen with a detection resolution of 0.25 ng/ml in phosphate buffer solution. Micromachining techniques are being used to integrate many (64 elements on the first test chip) identical SMR sensors into a single silicon chip which would be capable of simultaneously performing a wide variety of biomedical assays. The sensors require only a small printed circuit board and 8V power supply to operate and provide a readout. The presentation will describe the operation of the SMR sensor, the fabrication of the sensor array, and initial test results using commercially available animal immunoglobulins in laboratory-prepared test solutions.

IR Imaging has changed a great deal since it was last evaluated for medical applications. Systems are much more sensitive and much less expensive. Current uncooled imaging systems, which sell for less than $20,000 in production, are capable of NETDs of 0.05C and are as easy to use as a home video camera. The digital nature of today's imaging systems makes computer analysis and image archiving a straightforward data storage task. All of these advances are driving a reassessment of IR imaging for medical imaging applications. Several informal tests have indicated promise for diagnostic purposes, and trauma applications are being investigated. This paper will present uncooled imager test results and informal medical tests to date, as well as suggest some new areas for further work.

Immediate medical provision substantially reduces the number of fatalities sustained during military operations. However, the shift from large-scale regional conflicts to smaller peacekeeping and humanitarian missions has reduced the military medical support infrastructure. Civilian emergency medical services have long emphasized the 'golden hour' during which a patient must receive definitive medical attention. Without on-scene medical support, injured soldiers must be transported significant distances before receiving advanced medical care, and rapid transport to a medical facility is not always a viable option. Technological solutions enable military medics to deliver advanced medical care on the battlefield. We report here on the development of a small lightweight portable respirator for the treatment of far- forward battlefield casualties. The Far Forward Life Support System (FFLSS) utilizes a combination of COTS (commercial off the shelf) components and custom designed systems to provide ventilatory support to injured combatants. It also incorporates a small IV fluid pump and IV fluids for resuscitation. A microcompressor control system monitors both system performance and patient parameters for system control. Telemetry to a pager-like device worn by the front line medic alerts of any anomalies in ventilator or patient parameters, which will add greatly to triage decisions and resource management. Novel elements of the FLSS design include oxygen generation, low-pressure air generation, available patient suction, and the absence of any high pressure air cylinders. A prototype developed for animal testing will be described in detail as well as further design requirements for the human rated prototype.

For patients with ischemic stroke there is benefit to early treatment (within 3 hours) with recombinant tissue plasminogen activator, rt-PA, an FDA approved thrombolytic drug. The use of rt-PA within the first 3 hours of an ischemic stroke is based upon a clinical trial showing an increased probability of good functional recovery in the treated group. The challenge is now to individualize therapy in order to decrease the degree of permanent brain injury due to ischemia in as many patients as possible. This requires new tools to assay brian flood flow and tissue injury. However, there is currently no means to non-invasively monitor brain perfusion. There is no non-invasive method to determine whether administration of thrombolytic drug in an individual patient is actually effective in causing reperfusion. We have developed such a method based on using light in conjunction with periodic bolus injections of an optical vascular contrast agent to continuously monitor brain perfusion non-invasively.

This paper describes the principles and prototype architecture of a biosignal operating system for monitoring, diagnosing and treating diseases online. The distinguishing feature of the system is its ability to interface with the human body in a medically relevant manner. Three units in the system ensure machine-body interoperability. First is a biosignal acquisition and processing unit. The second unit draws conclusions from the acquired information while the third enables non-invasive therapies. The entire operation aims at locating the biological resources available for treatment and gaining access to them at run-time. This eliminates the need for medical records. In addition, a protocol for uniform disease definition eliminates the need for massive databasing and frequent updating. The drawback is that the system requires investigations into the biological resources of communication -- a gray area even in molecular biology. Preliminary tests, however, indicate that our technology supports online delivery of comprehensive medical services over the Internet.

On the battlefield of the future, it may become feasible for medics to perform, via application of new biomedical technologies, more sophisticated diagnoses and surgery than is currently practiced. Emerging biomedical technology may enable the medic to perform laparoscopic surgical procedures to remove, for example, shrapnel from injured soldiers. Battlefield conditions constrain the types of medical image acquisition and interpretation which can be performed. Ultrasound is the only viable biomedical imaging modality appropriate for deployment on the battlefield -- which leads to image interpretation issues because of the poor quality of ultrasound imagery. To help overcome these issues, we develop and implement a method of image enhancement which could aid non-experts in the rapid interpretation and use of ultrasound imagery. We describe an energy minimization approach to finding boundaries in medical images and show how prior information on edge orientation can be incorporated into this framework to detect tissue boundaries oriented at a known angle.

Ultrasound imaging is the most pervasive, cost effective, portable, high-resolution, and non-ionizing modality of diagnostic imaging available. The use of ultrasounds, however, has been hampered by the noise properties and poor contrast inherent in such imagery. A novel processing system is currently being developed that overcomes some of these disadvantages by producing a high-quality rendering of the anatomical structure of interest. In particular, a normal anatomical atlas is used as the starting point; this atlas is produced from either CT or MR imagery. As the ultrasound probe is moved along the body, image registration techniques, as well as external instrumentation that monitors the position and attitude of the ultrasound probe, are used to provide a continuous mapping between the ultrasound observations and the atlas. As discrepancies between the atlas and the observed anatomy occur, the atlas is deformed to reflect actual observations. Operated in this mode, the system displays the deformed high-resolution atlas to the user, providing a high- contrast, low-noise rendering of the patient's anatomy. In scenarios such as battlefield critical care, where large, immobile C/T or MR scanners are not feasible, deformation of a high quality atlas to match real-time ultrasound imagery can provide for much improved assessment and treatment possibilities.

The Life Support for Trauma and Transport (LSTAT) is an intensive care unit (ICU) in a 'stretcher' only 5 inches thick. LSTAT is a portable intensive care system which integrates state-of-the-art, commercial-off-the-shelf, hospital grade ICU devices into a single patient resuscitation, stabilization, evacuation, and surgical platform. LSTAT's current and evolving attributes include compact volume, low weight, integrated devices and subsystems, ergonomic patient-caregiver interface, patient and system information system, near-universal power interface, patient- caregiver hazardous environment isolation, and extensive evacuation vehicle interface compatibility. Although the LSTAT system architecture was established primarily to support diagnosis, monitoring and telemedicine consulting, the information architecture and communications suite can also support hosting training experiences and scenarios. The training scenario capabilities and features include: (1) moving training out to the field, (2) facilitating distributed training, (3) off-setting training with remote experts (or potentially embedded expert systems), and (4) facilitating training-by-simulation. Equipping the caregiver via such enhanced equipment and training should ultimately translate into better care for the patient.

Computer-based simulation is a goal for training physicians in specialties where traditional training puts patients at risk. Intuitively, interactive simulation of anatomy, pathology, and therapeutic actions should lead to shortening of the learning curve for novice or inexperienced physicians. Effective transfer of knowledge acquired in simulators must be shown for such devices to be widely accepted in the medical community. We have developed an Interventional Cardiology Training Simulator which incorporates real-time graphic interactivity coupled with haptic response, and an embedded curriculum permitting rehearsal, hypertext links, personal archiving and instructor review and testing capabilities. This linking of purely technical simulation with educational content creates a more robust educational purpose for procedural simulators.

This paper deals with the control design of haptic interfaces for virtual reality-based surgery simulations and training. It is well-known that realistic force reflection and realistic visual representations are among the most stringent requirements that are imposed by surgeons in this application domain. Our goal here is to develop adaptive control strategies that would facilitate the implementation of more realistic man-machine interface for the purpose of virtual reality based surgical simulations.