PerspectivesAre you interested in submitting a Perspective Article? Be sure to read The Science Advisory Board's Editorial Guides for Perspective Articles. Click here. Applying Biotechnological Advances to Aerospace Medicine by James E. Whinnery Ph.D.,M.D. Aerospace medicine is a crossroads specialty that touches wide sectors of our modern society, its economic structure, and the safety, security and health of earth’s human inhabitants. Aerospace medicine shares the roots of traditional clinical medicine in the understanding and treatment of disease, injury, and suffering. The physicians and scientists that endeavor to contribute to aerospace medicine receive their basic education in the established programs of clinical medicine and biomedical science. Divergence from the traditional science and practice of medicine begins with the primary clientele served by aerospace medical specialists. The main focus of aerospace medicine is the healthy human. The clinical problem facing the aerospace medicine physician lies in defining what constitutes a healthy human along with the range of variation that can be considered “normal.” The clientele of the aerospace medical specialist differs from that of the clinical medicine specialist by their participation in endeavors related to travel, life, work, and performance of activities in special environments above and away from the security of homeland Earth. There are challenges for a human aerospace voyager associated with activities undertaken outside the environmental envelope in which our evolutionary past has prepared us. The exposure to aerospace environmental stresses can be associated with exceeding human tolerance thereby resulting in compromise of normal function. When commanding control of an aerospace craft failure or compromise of normal function can be catastrophic. Even minimal alteration of normal psychophysiological function can threaten mission success and safety. Today aviation is no longer limited to only those special individuals who dare to escape the bounds of earthly existence. Within the period of a single century air travel has not only become possible it is now commonplace for almost everyone to take advantage of its benefits in a fast-paced society. Space travel is now on the brink of following close on the heels of air travel with a private citizen already having been in space and plans for space tourism well underway. Aerospace medicine has evolved instep with the remarkable technological advances in aerospace engineering. The aerospace medical community is now charged with applying their expertise to ensure the safety, security and health of every human in the aerospace environment; passengers and crew alike. Society now accepts air travel as a routine endeavor, similar to going for a weekend outing at the lake with essentially no additional concerns. In fact, air travel is considered overall to be a safer mode of travel than by automobile. Society can thank the aerospace community, including aircraft manufacturers and the airlines, for making such great strides in commercial aviation travel safety. However, it should not be forgotten that to even enter the aerospace environment requires life support to prevent death or incapacitation. Hypoxia, low temperature and reduced pressures are universally, acute stressors that require continuous protective measures be implemented to prevent death or incapacitation even in completely healthy humans. Acceleration (+Gz-stress) in fighter aircraft or civilian aerobatic flight can result in rapid-onset, unrecognized loss of consciousness (G-LOC). High altitude flight, especially in the high (north or south) latitudes, poses a cosmic and solar radiation exposure that must be recognized. Space travel has an even greater radiation threat. Occupational exposures especially, to all of theses stressors, both acutely and chronically (over a flying career), deserve careful consideration. The flight environment therefore differs significantly from the terrestrial environment and is the province of the aerospace medical specialist. As more individuals choose to enter the aviation and space environments, there is the need to define the “variants of normal” and the limitations of disease and disability in humans that may result in recommended restrictions to these aerospace stressors. Such safety concerns extend to both passengers and crew. Pilots must be selected and protected from incapacitation and passengers must remain asymptomatic and at least have the ability to egress from an aerospace craft. Both must be reasonably protected from acute injury, incapacitation, and longer-term health risks. Flying puts humans in a vehicle that can result in considerable restriction of an individual’s freedom and mobility lasting several hours (and potentially days) on long duration trips. Placed in an environment under the control of other’s, passengers depend on the environment provided to them. Pilot’s and crew assume considerable responsibility for the welfare of other’s both on-board and on the ground. Passenger’s also have a responsibility for each other’s welfare in emergency situations should they arise. Significant fiscal resources are in the balance based on the value of aerospace craft and the liability associated with any misadventure. Aviation is a major industry that has a considerable impact on many aspects of our modern economy. The economic impact of terrorist (11 September) activities and infectious disease (Severe Acute Respiratory Syndrome, SARS) on the aviation industry illustrate the severe and widespread impact on our well-being and sense of safety and security. The cost, inconvenience, loss of freedom, and annoyance resulting from such events take a significant toll on our way of life. A healthy global economy depends on a healthy aerospace industry. A healthy aerospace industry, in no short measure, depends on a healthy aerospace clientele. A healthy aerospace clientele is dependent on a talented, responsive aerospace medical support structure. The above description of the aerospace environment and the importance of the aerospace industry to society should serve to highlight why it has a distinctive value for modern society. Harnessing the scientific and technological power that has been developed by the biomedical community for pharmaceutical and clinical diagnostic development have widespread application in support of aerospace operations and aerospace medicine. Numerous scientists have stated that genomics will change the face of medicine and add important new dimensions to biomedical research. Application of molecular biological technology to aerospace problems likewise has promise to enhance the safety, security and health of a critically important segment of our lives. There are several areas of aerospace medicine where applications could prove exceptionally useful including clinical medicine, environmental stress, toxicology and environmental monitoring/security to mention only a few. In the clinical aerospace medicine arena, the future holds the promise to enhance the understanding of human health and disease based on molecular categorization. Even a complete reclassification could result. Instead of classification and treatment based on symptomatology and “macro-evidence” of structural changes; early detection, specific therapy and more definitive classification at the molecular level may be achievable. Guiding the pathway for recommendations regarding the suitability for flying, these possibilities have unusually attractive benefits for assuring safe pilot and crew qualification for duty. Such technology has the potential for increasing the safe window of opportunity for more human involvement in aerospace activities. Removing unnecessary restrictions from flying based on previously less specific diagnostic criteria would be the desired result. Prediction of adverse pharmacological responses and pre-symptomatic illness/disease in crewmembers would also have great benefit in aerospace medicine. In the operational aerospace arena, there is the need for understanding the response to the stresses of importance in the aerospace environment, including definition of the gene expression to hypoxia and acceleration. Is there a unique molecular response signature to exceeding tolerance to these stressors? What is the gene expression associated with loss of consciousness? Can fatigue be quantitatively defined and utilized to determine suitability for flight? Can molecular biological sensors and integrated sensor systems be useful in ensuring vehicle environmental quality in a reliable, sensitive, cost effective manner? Are there molecular markers that can be utilized for radiation exposure monitoring? Application of toxicogenomics to aerospace operations and accident investigation should pay big safety dividends in defining the adverse implications of alcohol, drugs, medications, smoke and toxic fire products. As in other areas, careful implementation with close attention to ethical and individual rights concerns are of critical importance in aerospace medicine also. The technology should be utilized to assist those who desire to enter the aerospace realm in a manner that will reduce risks and enhance their safety, security and health. It can be employed to safely widen the envelope for those who want to journey to new and potentially stressful frontiers away from earth. In this year that marks the century of flight it is appropriate to consider how we will apply the wonders of advanced biotechnology to boost aerospace safety, security, accessibility, and health for everyone who enters that realm. ### << Previous Next >> [ View All Perspectives ] |
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