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radioactive materials is accomplished by treating the patient in a single location, controlling access to that location, and by using standard contact precautions Internal contamination Internal contamination can be a serious problem because it is difficult to eliminate some long-lived radioactive materials from within the body Death due to radiation from internal contamination is rare A few deaths have been caused by medical misadministrations A familiar example of intentional, nonlethal internal contamination is the bone scan performed in a nuclear medicine department Treatment of hyperthyroidism with 131I (radioactive iodine) also is, in a sense, planned internal contamination Metal fragment Another source of possible contamination is the radioactive metallic fragment, which can be intensely radioactive These could, in principle, be found if a “dirty bomb” was constructed with a radioactive metal source such as 192Ir (radioactive iridium) Radioactive metal fragments can be embedded in the patient’s skin and should never be touched with the examiner’s fingers Tongs or forceps will increase the distance between the radioactive metal fragment and the fingers, and thus greatly reduce any radiation dose to the healthcare worker Hot particles “Hot” particles are microscopic particles that can be highly radioactive Typically, they contain 60Co (radioactive cobalt) or other fission products and might be found on a nuclear reactor worker after a reactor accident These particles can be difficult to localize and remove and may give a large radiation dose to a small volume of tissues If the particle is trapped under a nail or is in the fold of the skin, routine washings may not dislodge it The particle can sometimes be localized by using a thick piece of lead If the lead is placed between the particle and the radiation detector, the exposure rate should decrease substantially Once the particle is localized, it can usually be removed by using simple mechanical means Rarely, a punch biopsy of the skin may be necessary Terrorist events Nuclear materials may be used intentionally in a terrorist event An intact sealed source could be placed in a populated area, generating whole-body exposures but no contamination A conventional explosive combined with radioactive materials, the so-called “dirty bomb,” could be employed to disseminate radioactive materials over an area Victims of such an attack would likely have radiation exposure as well as injuries from the explosion itself An attack on a research or commercial power reactor could produce a large-scale dispersion of nuclear material; victims could be exposed to whole-body and localized radiation, as well as internal and external contamination Transported nuclear materials such as radiopharmaceuticals or radioactive waste could be the subject of a terrorist attack The effects would vary depending on whether the containers were breached—intact containers would produce only potential exposures, whereas destruction of the containers and dispersal of their contents could also lead to contamination A “dud” nuclear weapon that does not undergo a nuclear fission reaction would still disperse radioactive materials by the associated conventional explosion, leading to contamination in addition to effects from the conventional explosion itself A nuclear weapon effectively detonated by a terrorist group might be relatively small scale but still capable of widespread damage, including thermal and blast effects from the denotation along with contamination and exposure of affected persons Triage Considerations Triage and management should focus on securing ABCs (airway, breathing, circulation) and monitoring vital signs Major trauma, burns, and respiratory injury should be treated first No survivable radiation injury requires direct immediate lifesaving treatment; hence, medical staff should focus their attention on the treatment of non–radiation-related, life-threatening conditions Once stabilized, the radiation-related injuries can be addressed In addition to routine trauma labs, it is recommended that a CBC be obtained to assess lymphocyte count Because there is no immediate treatment of radiation exposure, the problem of radioactive contamination should be addressed first In most circumstances, a Geiger counter can be used to determine the presence of contamination The probability of contamination can be assessed by obtaining an accurate description of the accident and the likely radiation source If the patient is a radiation worker, finding his or her radiation badge and performing a “reenactment” of the accident may be critical for dose estimation Management and Diagnostic Studies Internal Contamination Treatment of internal contamination is most effective if initiated promptly The requirement for prompt treatment is a dilemma for the physician as it is difficult to determine if internal contamination is present until the external contamination has been removed Moistened cotton Q-tips can be used to perform nasal swabs If these show radioactivity, inhalation of radioactive materials is possible The nature of the accident may provide clues to the possibility of internal contamination (e.g., a fire with smoke leading to the inhalation of radioactive particles) The most effective treatment requires knowledge of the radionuclide involved and its chemical form This information is usually not immediately available Fortunately, there are simple general treatment measures that can be effectively instituted before the magnitude of the internal contamination is fully known TABLE 90.16 DOSE OF STABLE IODINE (SSKI a ) BY AGE Age Dose (po) (mg) 18 yrs 130 a SSKI (saturated solution of potassium iodide) If given soon after exposure, stable iodine (saturated solution of potassium iodide [SSKI]) is effective for preventing the uptake of radioactive iodine by the thyroid gland Prompt administration of stable iodine should be considered if there is a possibility of external contamination, or ingestion or inhalation of radioactive iodine ( Table 90.16 ) Because radioactive iodine is volatile, it is likely to be inhaled If a contaminated child were brought to the ED after an accident with a radiopharmaceutical truck carrying radioactive iodine, administration of stable iodine would be appropriate Of note, for a given internal contamination level, the radiation dose to the thyroid for infants is eight or nine times as large as that for adults If further investigation revealed no radioactive iodine, little harm would have been done by having administered the stable iodine A single dose of oral iodine is highly unlikely to cause any adverse reactions, even in persons who have serious reactions to iodinated contrast agents or seafood After a nuclear reactor accident that results in the release of a large amount of radioactive iodine, three steps can be taken to minimize the adverse effects on the public First, the public should be sheltered or evacuated to prevent further exposure via fallout or gaseous materials Second, potassium iodide (KI) may be administered if available However, it is important to note that many of the nuclear reactors in the United States not house radioactive iodine, making KI a non-useful treatment option Third, the food supply should be monitored carefully to prevent further ingestion of radioactive iodine or other radionuclides If a reactor accident occurs that involves contamination of the public, understandable concern by members of the public will ensue If this happens, emergency medical facilities should try to preserve their valuable resources for patients who need lifesaving medical treatment Plans may need to be made to refer uninjured persons and persons with minor injuries to other facilities It may be prudent to prevent hospitals from becoming decontamination centers Several simple steps can be taken to treat internal contamination nonspecifically The goals of treatment are to prevent the absorption of the radionuclide and to enhance its excretion Safe techniques that can prevent the absorption of radionuclides include the administration of activated charcoal and alginate-containing antacids Enhanced excretion can be achieved by hydration and administration of a purgative Specific treatment of internal contamination depends on the radionuclide, its chemical and physical forms, and the route of internal contamination Recommendations for many specific treatments can be found in the NCRP Report 161, titled Management of Persons Contaminated with Radionuclides This report should be available in every hospital ED and can be downloaded for free from the NCRP website (http://www.ncrponline.org ) ( Fig 90.14 ) Initiation of treatments that entail some risk to the patient (e.g., pulmonary lavage, intravenous chelating agents) should be undertaken only after consultation with experts The benefits of the treatment should be significantly greater than the risks  ... contamination of the public, understandable concern by members of the public will ensue If this happens, emergency medical facilities should try to preserve their valuable resources for patients who need