Acute radiation symptoms

B. Exposures to very high concentrations of tritium can cause intakes large enough to induce acute radiation symptoms. An accidental exposure leading to a multicurie dose of tritium induced nausea and exhaustion and eventual death of a victim (Conklin 87). Other estimates put the LD 50 at about 10 Ci this corresponds to about 1 mg of pure tritium. (Sublette 97) This is about the mass of a lethal dose of the nerve agent sarin (Sublette 97). 

Acute Radiation Syndrome—The symptoms which taken together characterize a person suffering from the effects of intense radiation. The effects occur within hours or days. 

Specific health effects resulting from an acute dose appear only after the victim exceeds a dose threshold. That is, the health effect will not occur if doses are below the threshold. (Note that this is significantly different from the LNT model used to predict stochastic effects.) After reaching the acute dose threshold, a receptor can experience symptoms of radiation sickness, also called acute radiation syndrome. As shown in Table 3.2, the severity of the symptoms increases with dose, ranging from mild nausea starting around 25-35 rad (0.25-0.35 Gy) to death at doses that reach 300-400 rad (3-4 Gy). Table 3.2 shows that the range of health effects varies by both total dose and time after exposure. 

Mental retardation and microcephaly Acute stress symptoms, posttraumatic stress symptoms Personality disorders A-bomb neurosis or radiation response syndrome excessive anxiety over symptoms of exposure, fear of cancer, subclinical stress symptoms... 

A. Prodromal Phase. The initial phase of prodromal symptoms is characterized by the relatively rapid onset of nausea, vomiting, and malaise. This is a nonspecific clinical response to acute radiation exposure. It is not diagnostic of the degree of radiation injury however, in the absence of associated trauma and an early onset, it does suggest a large radiation exposure. The duration of this prodromal phase is short, generally a few hours, and the incapacitation should not be severe enough to warrant evacuation of military personnel away from their units. 

The client is diagnosed with acute radiation syndrome (ARS). Which signs and symptoms would the nurse assess in the acute phase ... 

Clearly, an exploded nuclear device could result in a lot of property damage. People would be killed or injured from the blast and might be contaminated by radioactive material. Many people could have symptoms of acute radiation syndrome. After a nuclear explosion, radioactive fallout would extend over a large region far from the point of impact, potentially increasing people s risk of developing cancer over time. 

A. Acute radiation syndrome (ARS) consists of a constellation of symptoms and signs indicative of systemic radiation injury. It is often described in four stages (prodrome, latency, manifest illness, and recovery). The onset and severity of each stage of radiation poisoning are detennined largely by the dose. 

Two staff died immediately in the accident, either in the explosion or in the subsequent fire. Twenty-nine others died in the following few days as a result of intense / -exposure causing extensive radiation burns of the skin. Two hundred and seventy-one other people were admitted to hospital of whom 174 suffered symptoms of acute radiation syndrome, having received whole-body y-irradiation doses between 2 and 16 gray. 

Acute radiation syndrome—A serious illness caused by receiving a dose of more than 50 Rads of penetrating radiation to the body in a short time (usually minutes). The early symptoms include nausea, fatigue, vomiting, and diarrhea with loss of hair, and swelling of the mouth and throat, followed by general loss of energy. 

High dose rates are usually acute exposures rather than continuous, chronic exposures. Their effects include ulceration of skin and intestinal tissue and reductions in white cell production. Symptoms of acute radiation sickness are weakness, sleepiness and eventually stupor, tremors, convulsions, and death. Symptoms may include nausea, vomiting and diarrhea, loss of hair, and bleeding. Death may occur after one or two days or have delays of several weeks. 

A dose of some 200 rem or more to the whole body may give rise to an acute radiation syndrome. The response, depending on the intensity of the dose, begins with vomiting and diarrhoea within a few hours. By the second or third day there is an improvement, but the blood count falls. By the fifth day there is a return of symptoms, with fever and infection. 

Long-term exposure to low-level radiation is more likely to cause the problems just described than are short exposures to intense radiation. Short-term intense radiation tends to destroy tissue rapidly in the area exposed and can cause symptoms of so-called acute radiation syndrome. Some of these symptoms are given in I Table 10.3. It is this rapid destruction of tissue that makes relatively intense radiation a useful tool in the treatment of some cancers. 

Table 12.1 The Nature and timing of signs and symptoms of the acute radiation syndrome...

Acute radiation syndrome can be classified according to the dose of radiation received. These dose ranges are not precise figures but do offer a guide to likely symptoms. The LD50 at 60 days without treatment is approximately 3.5 Sv, which increases to >6 Sv with increasing medical intervention (Table 6.5). 

Box 6.5 Early symptoms of severe acute radiation exposure... 

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