The symptoms and signs of radiation exposure occur in three phases: prodromal, latent, and symptomatic.

Prodromal Phase

Patients will develop nonspecific symptoms of nausea, vomiting, weakness, and fatigue. Symptoms generally last no longer than 24–48 hours. With higher radiation exposures, symptoms will occur earlier and last longer.

Latent Period

The latent period duration depends on the dose of radiation and the body system involved (neurologic, several hours; gastrointestinal, 1–7 days; hematopoietic, 2–6 weeks).

Symptomatic Phase

Symptoms will depend largely on the body system affected, which will depend on the radiation dose. At doses of 0.7–4 Gy, the hematopoietic system will begin to manifest signs and symptoms of bone marrow suppression. Because of their long life span, erythrocytes are less severely affected than are the myeloid and platelet cell lines. Neutropenia and thrombocytopenia may be significant and lead to infectious and hemorrhagic complications. At doses of 6–8 Gy, gastrointestinal symptoms develop. Nausea, vomiting, diarrhea (bloody), and severe fluid and electrolyte imbalances will occur. The neurovascular system becomes affected at doses of 20–40 Gy. Symptoms include headache, mental status changes, hypotension, focal neurologic changes, convulsions, and coma. Exposures in this range are uniformly fatal.

Laboratory and X-Ray Findings

Obtain a complete blood count with differential for all patients sustaining a radiation injury. Although symptomatic bone marrow suppression may not be evident for some weeks, a drop of the absolute lymphocyte count of 50% at 24–48 hours is indicative of significant exposure. Monitor electrolytes in patients with gastrointestinal symptoms.





Detonation of a nuclear bomb or the detonation of a conventional explosive that also dispersed radioactive material (so-called dirty bomb).


There are four types of radioactive particles that may cause damage when they interact with body tissue:

  1. Alpha particles are large particles that are stopped by the epidermis and cause no significant external damage. Internal contamination, from the inhalation or ingestion of contaminated particles, may cause local tissue injury.

  2. Beta particles are small particles that can penetrate the superficial skin and cause mild-burn-type injuries.

  3. Gamma rays are high-energy particles that can enter tissues easily and cause significant damage to multiple body systems.

  4. Neutrons are large particles that are typically produced only during nuclear detonation. Like gamma rays, they cause significant tissue injury.

The effect that radiation will have on the body depends on the type of radiation, the amount of exposure, and the body system involved. Tissues that display higher rates of cellular mitosis, such as the gastrointestinal and hematopoietic systems, are more severely affected. At very high radiation doses, neurovascular effects will also be seen. Radiation injury may cause either abnormal cell function or cell death.


Content 9


In the absence of aggressive medical therapy, the LD50 (the dose of radiation that will kill 50% of those exposed) is approximately 3.5 Gy. Aggressive medical care affords improved survival. Treat all life-threatening injuries associated with blast or thermal effects according to standard advanced trauma life support protocols. Perform surgical procedures early to avoid the electrolyte and hematopoietic effects that will occur. Clean wounds extensively and close them as soon as possible to prevent infection. Treat nausea and vomiting with standard antiemetic medications (prochlorperazine, promethazine, ondansetron). Treat fluid and electrolyte abnormalities with appropriate replacement. Anemia and thrombocytopenia can be treated with transfusion therapy. Leukopenia may be treated with hematopoietic growth factors such as sargramostim and filgrastim. In some instances, bone marrow transplantation may be utilized. Follow neutropenic precautions at absolute neutrophil counts below 500. Some authors recommend prophylactic antibiotics at counts below 100. Use broad-spectrum antibiotics to treat infections. Infection is the most common cause of death in radiation patients.


Remove all contaminated clothing. Change contaminated dressings and splints. Thoroughly clean the patient's skin with soap and water or a 0.5% hypochlorite solution. Hair should be washed and in some instances removed. Eyes may be washed with large amounts of water or sterile saline. All contaminated materials should be bagged if possible and sent for proper disposal.


Patients who have been decontaminated and have only mild transient symptoms can be safely discharged. Because of the variable and lengthy latent period involved with this disorder, early admission is not indicated. Patients should be closely monitored and admitted when warranted.

Bushberg JT, Kroger LA, Hartman MB, Leidholdt EM Jr, Miller KL, Derlet R, Wraa C: Nuclear/radiological terrorism: Emergency department management of radiation casualties. J Emerg Med 2007;32:71–85  [PubMed: 17239736] .
Coleman CN, Hrdina C, Bader JL, Norwood A, Hayhurst R, Forsha J, Yeskey K, Knebel A: Medical response to a radiologic/nuclear event: integrated plan from the Office of the Assistant Secretary for Preparedness and Response, Department of Health and Human Services. Ann Emerg Med 2009;53:213–222  [PubMed: 18387707] .


Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.


Content 3

Content 13

Content 11

Question 1 of 1

A "dirty" bomb is detonated in downtown Boston. The bomb was composed of cesium-137 with trinitrotoluene. In the immediate aftermath, an estimated 30 people were killed because of the power of the blast. The fallout area was about 0.5 mile, with radiation exposure of about 1.8 Gy. An estimated 5000 people have been potentially exposed to beta and gamma radiation. Most of these individuals show no sign of any injury, but about 60 people have evidence of thermal injury.

What is the most appropriate approach to treating the injured victims?



Content 2

Content 3


USMLE Reviewer (Subscription Required)