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leak of radioactive material, or detonation of a radiation dispersal device made from highly radioactive
material. The two most radiosensitive organ systems in the human body are the hematopoietic (blood
forming) and gastrointestinal (GI).
Subjective: Symptoms
Three phases: 1. Prodrome: (within hours of exposure) nausea, vomiting, diarrhea, fatigue, weakness, fever
and headache; time to onset, duration and severity of these symptoms varies with radiation dose received. 2.
Relatively symptom-free latent phase, lasting 2-6 weeks depending on dose received. 3. Clinical symptoms in
the affected major organ system (hematopoietic, gastrointestinal, neurovascular).
Objective: Signs
Using Basic Tools: Dose dependent: Survivable dose- no objective physical signs; higher dose- signs of
bone marrow suppression (infection, bleeding) or gastrointestinal syndrome (GI bleeding, diarrhea) follow
days to weeks after exposure; concomitant trauma.
Using Advanced Tools: Lab: WBC count immediately and q 4 h (50% drop in lymphocytes within the first
24 hours, with total lymphocyte count less than 1x109 indicates significant radiation injury);
If patient not evacuated: Draw 15 cc of peripheral blood in a heparinized tube, refrigerate and forward it with
patient for analysis in cytogenetic lab for biodosimetry (estimate of dose received). Collect baseline urine and
stool samples for evaluation of internal contamination (first 24 hours following injury);
Radiation Monitoring (if available): Whole-body monitoring with RADIACS meter or assessment of inhalation
injury with nasal swabs (forward for analysis) for anyone not wearing respiratory protection (protective mask).
Assessment:
Differential Diagnosis - radiogenic vomiting may be confused with psychogenic vomiting that often
results from stress and fear reactions.
Plan:
Treatment
Primary:
Decontaminate following stabilization. Soap and water are 95% effective.
Control radiogenic emesis with antiemetics: Granisetron (Kytril) 1 mg IV over 30 seconds or ondansetron
(Zofran) 8 mg IM, or IV over 30 seconds are best.
Patient Education
General: A patient who receives a minimal dose should be reassured and returned to duty. A patient with
any lymphocyte depletion within the first 24 hours should be evacuated as quickly as possible for definitive
care of subsequent infectious and gastrointestinal complications.
Diet: No special diet is indicated.
Medications: Antiemetic drugs may cause drowsiness.
Prevention and Hygiene: Definitive surgical management of associated wounds and trauma must be
completed within 36 hours in a patient with significant radiologic injury so as to avoid infection and increased
morbidity associated with poor wound healing.
No Improvement/Deterioration: Evaluate for signs of infection.
Wound Care: As above, definitive wound care within 36 hours of injury is mandated.
Follow-up Actions
Evacuation/Consultation Criteria: Evacuate a patient with suspected significant radiologic injury as soon
as possible. NOTE: A variety of antidotes are available for specialized treatment of internal contamination.
Common ones include potassium or sodium iodide (KI or NaI) to prevent thyroid uptake of radioactive
iodine, which occurs after reactor accidents. Significant internal contamination by plutonium, the primary
radioactive contaminant in nuclear weapons accidents, is treated with chelating agents such as calcium
diethylenetriaminepentaacetic acid (DPTA).