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16356590.Pdf 1 MILITARY AND CIVIL DEFENSE ASPECTS OF THE ACUTE RADIATION SYNDROME IN MAN HERBERT B. GERSTNER, M. D. Deportment of Radiobiology 58-6 Air University SCHOOL OF AVIATION MEDICINE, USAF RANDOLPH AFB, TEXAS November 1957 MILITARY AND CIVIL DEFENSE ASPECTS OF THE ACUTE RADIATION SYNDROME IN MAN From a compatative analysis of human data derived from nuclear accidents, Japanese bomb casualties, and radiotherapy patients, emerges the clinical picture of the acute radiation syndrome with its three subdivisions - hematopoietic, gastrointestinal, and cerebrai forms. Dependency of the picture on dose level and individual susceptibility is discussed, and the therapeutic management is outlined. Since penetrating ionizing radiation represents a potential casualty-causing agent, problems facing the practical physician under catastrophic conditions are evaluated. In an address to the 62d Annual Convention o/ the Association of Military Surgeons o/ the United States held in November 19.55, hlaior General lames P. Cooney, Deputy Surgeon General o/ the Army, stated (I): “In the past ten years a great deal o/ effort has been spent in trying to understand and teach various detailed eflects o/ nuclear weapons. Some of the effort has in- volved discussions of detailed physics and mathematics relating to the bomb and the micm- seconds following the detonation. This approach has led to a preoccupation with details that will not help us as medical people to solve the casualty problems. In addition. the preoccupation with these details has resulted in the creation of an aura of mystety around the weapon that has prevented the average individual from understanding the things that are essential to him and to his neighbor if they are to survive.” INTRODUCTION difficult to arrive at an objective and sen- sible judgment. Now that nuclear energy is already producing electricity, propelling ships, and forming the The present report, restricted to the acute basis for devastating weapons, and now that effects of human whole-body exposure to long-range ballistic missiles capable of carrying penetrating ionizing radiation, attempts a nuclear warheads can be assumed to exist, every- realistic evaluation of facts as they are known body concerned with practical medicine is at this time. Clinical features essential from compelled to acquaint himself with effects of the standpoint of the practical physician and ionizing radiation on man. Widespread ignorance the medical officer have been emphasized, of these effects may be attributed to the fact that while those of more academic interest have presently known parts of the data are too widely been omitted or treated cursorily. Such an dispersed over numerous protessional journals, endeavor to present to the practitioner a coherent or hidden in practically inaccessible documents, and unified clinicopathologic concept on which to allow easy composition of a comprehensive to base his actions, necessarily must involve picture; also, the factual evidence is frequently oversimplifications that, with increasing infor- clouded by emotional and political consid- mation, may be subject to revision. erations. Under these circumstances it IS In case of accidental or intentional nuclear Received for publication on 19 July 1957. explosions, an estimate can be made of the 1 50-6 air dose of penetrating ionizing radiation to within 2 or 3 days, hospitalization becomes which a group of persons has been exposed. necessary. Manifestations of severe bone marrow The physician then called into action will depression - characterized hematologically by face two questions of paramount importance: leukopenia, thrombocytopenia, and anemi a - (1) Is it possible, from the air dose, to predict appear in the form of frank hemorrhages, purpura, the fate of the exposed persons-that is, to susceptibility to infection (especially in the arrive at a reasonably correct prognosis? oral cavity), fever, and other signs and symptoms (2) Is it conceivable, from the air dose, to associated with such disorders of the blood anticipate for a population the degree and the picture. This phase of aplastic anemia cul- time course of the ensuing disease, and thereby minates about the 30th day when the patient to estimate the medical requirements - personnel, passes through a critical state. Thereafter hospital beds, and supplies? recovery starts and becomes obvious between the 40th and 50th days; when fever disappears, THE “TYPICAL” ACUTE RADIATION SYNDROME infectious lesions in the oral cavity heal, and Exposure to a sufficient amount of penetrating the blood picture approaches normal values. x-ray, gamma, or neutron radiation causes Convalescence begins after the 60th day and in man characteristic clinical sequelae -the is followed by resumption of work and normal acute radiation syndrome. This complex of life approximately 3 months postexposure. signs and symptoms, unfolding along a rather According to their chronologic sequence, fixed time schedule, forms a peculiar picture four distinct stages of the acute radiation that is as well defined as “lobar pneumonia” syndrome can thus be established -namely, or “typhoid.” prodromal, latent, bone marrow depression or The most conspicuous features of the “typical” aplastic anemia, and recovery phases (fig. 1 radiation-induced disease are as follows: Within and ref. 2). Of course. the “typical” disease, 2 hours after exposure, complaints pointing as described above. will be subject to variation to an “upset stomach” develop rather abruptly; and modification brought about essentially by anorexia, nausea, and malaise are predominant two factors -dose and individual susceptibility. and are accompanied by listlessness, drow- Before these modifications can be discussed, siness, and fatigue. Deterioration of the indi- however, a survey must be made of the material vidual’s general condition progresses rapidly on which the analysis is based. and leads to profuse vomiting, extreme weakness, or even prostration. This early reaction cul- ORIGIN OF DATA USED FOR EVALUATION minates about 8 hours after exposure and then subsides rather quickly. On the 2d postradiation The largest group of persons exposed to day, nausea and occasional vomiting persist nuclear radiation is represented by the popu- but the general condition is markedly improved; lations of Hiroshima and Kagasaki. Careful on the 3d postradiation day all compiaints and comprehensive clinical (2, 3) as well as have disappeared. To avoid confusion, the pathologic (3, 6) observations are available. burst of eariy signs and symptoms should noc Although these data are outstanding for estab- be designated as “radiation sickness” but lishing consequences of human exposure to rather as “initial reaction” or as the “prodromal ionizing radiation, they are of rather limited phase” of the acute radiation syndrome. After value for deriving dose-effect relationships, dissipation of prodromal effects, the patient since frequently even a rough estimate of the is asymptomatic and capable of performing dose is impossible. Subsequently, reference normal work, or even of exerting strenuous to the Japanese bomb casualties appears under physical effort. This favorable state, the the abbreviation JBC. On 1 March 1954, the tt latent period,” may extend to the 19th or 20th test explosion of a hydrogen device at Bikini postradiation day, when a new phase is entered Atoll accidentally exposed 28 Americans and rather abruptly. As in the acute onset of an 239 Marshallese to fallout radiation. Deter- infectious disease, the patient experiences minations oi dose and clinical sequelae are chills, malaise, a feverish feeling, fatigue, well documented (5, 6, 7). According to the and shortness of breath on exertion. Again the four islands on which these persons were general condition deteriorates rapidly and, located, four dose groups can be formed that 58-6 will subsequently be designated as h~/,(Utirik), numbering of the patients. On 2 June 1952, at .M/, (Ailinginae), Ai/, (Rongcrik), and All, (Ronge- the Argonne National Laboratory, 4 persons lap Atoll). During the same test shot, 23 were exposed to neutron and gamma radiations Japanese aboard a fishing boat were also ex- released by the accidental excursion of a water- posed to fallout radiation. This group, for moderated critical assembly. Doses and clinical which dose and clinical sequelae are relatively pictures have been well established for each well known (8, 9, lo), will subsequently be individual patient (13). These cases will be designated as IF. designated as A,, A,. A,, and A,. At the Geneva Two nuclear accidents occurred at the Los Conference on Peaceful Uses of Atomic Energy, Alamos Scientific Laboratory. Uncontrolled fis- Guskova et al. (14) reported 2 Russian cases sion reactions caused the inadvertent exposure of the acute radiation syndrome as the result of 10 persons to complex ionizing radiation. of a short gamma and neutron irradiation, after Detailed analysis of dose (11) and clinical the rules of operating an experimental reactor course (12) are available for 9 of these cases. had been violated. These 2 patients, for whom They will be designated as LA, . LA,,, dose and clinical course are well reported, keeping the indices identical with Hempelmann’s will be designated as R, and R,. LATENT PHASE I I\ I I DAYS I WEEKS POST EXPOSURE I POST EXPOSURE FIGURE 1 Schematic drawing showing the typical clinicai course of the acute radiation syndrome (hematopoietic tom). The platelet count would parallel the WBC, while lymphocytes wuld decline
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