Rosen & Barkin's 5-Minute Emergency Medicine Consult (596 page)

• Recognized exposure:
  
  • Occupational, medical, transportation accident
    
• Unrecognized or clandestine exposure:
  
  • Radiologic dispersal device (RDD), concealed or unrecognized source
    
  • Industrial and medical radiography sources may be pellets, only a few millimeters in diameter and are highly radioactive.
    
  • Suspect if multiple patients present with symptoms of ARS at any stage, burns without history of thermal exposure, or ischemic ulcers in unusual locations (e.g., hand from handling unrecognized source, hip from placing source in pocket).
    

• Whole-body exposure:
  
  • Nausea, vomiting:
    
    • Within 3–6 hr for >100 rad exposure; sooner with higher exposures
      
    • Vomiting within 1 hr of exposure indicates potentially lethal injury (>600 rad).
      
  • Confusion and weakness (>200 rad)
    
  • Fever:
    
    • Acutely, from inflammation
      
    • During manifest illness, from infection
      
  • Hair loss, hemorrhage, diarrhea may develop with doses >300 rad.
    
• Dermal exposure:
  
  • Initial erythema
    
  • Blistering and ischemic necrosis may follow.
    

• Survey for radiation
  using a
  Geiger counter
  , which can be found in any nuclear medicine or radiation therapy department:
  
  • Any probe style is acceptable for survey.
    
  • Cover probe with exam glove:
    
    • Prevents contamination of probe
      
    • Blocks α radiation but detects β/γ
      
  • Measure background radiation away from patient.
    
  • Move probe slowly over patient’s skin:
    
    • 1–2 cm from skin
      
    • Move probe only 2–3 cm/sec.
      
    • Contamination is >2 × background radiation level.
      
    • Note any contaminated areas.
      
    • Follow systematic pattern to avoid missing areas.
      
    • Remember to survey palms, soles, hair.
      
• Absolute lymphocyte count (ALC)
  is the best indicator of severity of ARS:
  
  • <1,000/mm
    ³
    : Moderate exposure, 200–600 rad
    
  • <500/mm
    ³
    : Severe exposure, >600 rad
    

• CBC with differential every 4–6 hr (for 24 hr or until stable)
  
• Swab both nares and survey swab for inhaled contaminants.
  
• Type and cross-match blood.
  
• 24-hr stool for radioassay if GI contamination suspected
  
• 24-hr urine for radioassay if any internal contamination is suspected
  

• Diagnostic imaging as clinically indicated
  
• Whole-body gamma camera (without collimator) is best for ruling out internal contamination with low levels of radioisotopes, if suspicion is high and survey with Geiger counter is negative.
  

Cytogenetics allows more accurate dose assessment:

• 10 mL blood in lithium-heparin tube (ethylenediaminetetraacetic acid also acceptable)
  
• Draw 24 hr postexposure.
  
• Refrigerate (4°C) and ship cold to Radiation Emergency Assistance Center/Training Site (REAC/TS).
  
• Only limited number of samples can be processed due to resources required.
  

• Systemic illness: Lymphopenia, weakness, nausea:
  
  • Psychological effects are common in both exposed and unexposed patients and may mimic ARS:
    
    • Radiation casualty with vomiting from ARS should have falling ALC; if ALC normal and stable, consider psychological stress reaction or other type of illness.
      
  • Hematologic malignancy
    
  • Chemical warfare agents (blister/mustard)
    
  • HIV disease, immunosuppression
    
• Skin injuries:
  
  • Ischemic ulcer
    
  • Brown recluse spider bite
    
  • Pyoderma gangrenosum
    

TREATMENT

Personal protective equipment (PPE):

• Must provide protection from dust (particulate respirator; e.g., N-95, gown, gloves, hair, and shoe covers)
  
• Radiography aprons are of no value—they do not protect against most γ radiation.
  

• Treat life threats (airway, breathing, and circulation management [ABCs]).
  
• Assess any bombing scene for radioactive contamination (RDD).
  
• Removing clothing will eliminate about 80% of external contamination.
  
• Survey for residual contamination:
  
  • No contamination: Patient may be cared for as usual.
    
  • If contamination is present, assess medical condition:
    
    • Stable: Proceed with decontamination.
      
    • Unstable: Provide necessary care and transport; use sheets to control contamination.
      

• ABCs
  
• Assess for contamination.
  
• If patient condition permits, perform decontamination before patient enters (and contaminates) facility.
  
• Minimize staff exposure:
  
  • Time
    : Limit time in contaminated area, remove contaminated material often.
    
  • Distance
    : Use long-handled instruments to handle contaminated material.
    
  • Shielding
    : Place contaminated material in a lead container (available in nuclear medicine department); radiography lead aprons are not effective.
    

• Hospital issues:
  
  • Activate hospital disaster plan, if indicated, to mobilize resources.
    
  • Designate contaminated and “clean” treatment areas.
    
  • Appoint a temporary radiation safety officer (RSO) for incident to survey all patients and staff and all materials leaving treatment area
    
    • Any staff member who is trained to use Geiger counter and dosimeters may fill RSO role initially if necessary.
      
  • Patients and materials that are not contaminated do not need decontamination or containment.
    
  • Call for expert assistance: Hospital RSO, local department of nuclear safety, health department, or REAC/TS.
    
• Staff issues:
  
  • Provide PPE and psychological support as described above.
    
  • Assign pregnant personnel to “clean” areas only.
    
• Decontamination:
  
  • Priorities: Wounds > mucous membranes > intact skin
    
  • Use fenestrated drapes to shield adjacent skin.
    
  • Use soap and water; no harsh chemicals.
    
  • Diaper wipes work well for intact skin; wipe from edges of area to center, then lift away.
    
  • Irrigate wounds—collect and survey runoff, avoid splashing.
    
  • Resurvey frequently to assess effectiveness of decontamination.
    
  • Do not abrade skin.
    
  • If contamination cannot be removed, cover area to prevent spread and move on—residual contamination can be controlled.
    
• RDD:
  
  • Necessary surgery must be done immediately (36–48 hr), or else delayed 1–2 mo, with exposure >200 rad.
    
  • Any bombing victim must be assessed for radioactive contamination until RDD is ruled out by assessment of scene.
    
  • Preserve evidence for criminal investigation.
    
• Treat vomiting and dehydration:
  
  • Antiemetics (ondansetron)
    
  • IV fluids
    
• Decorporation agents for internal decontamination are specific to each radionuclide:
  
  • Contact REAC/TS for guidance (see below).
    
• Cytokines and transfusions may be needed with doses >200 rad.
  
• Potassium iodide:
  
  • Useful only to prevent thyroid uptake of radioactive iodine (found in nuclear reactors), and only if given within 4 hr after contamination. See
    www.remm.nlm.gov/potassiumiodide.htm
    for more information.
    

• Ondansetron 8 mg IV (or equivalent 5-HT3 serotonin antagonist)
  
• Potassium iodide:
  
  • Adults: 130 mg PO per day
    
  • Children:
    
    • 3–18 yr: 65 mg PO per day
      
    • 1 mo to 3 yr: 32 mg PO per day
      
    • <1 mo: 16 mg PO per day
      

FOLLOW-UP

• Lymphocyte count <1,000 at 24–48 hr postexposure
  
• Lymphocyte count decreased 50% at 24–48 hr
  
• Suspect acute exposure >200 rad
  
• Significant trauma or other illness
  
• Uncontrolled vomiting
  
• When in doubt, admit for serial CBC and obtain consultation
  

• No residual contamination
  
• No evidence of acute exposure >100 rad
  
• Tolerating oral fluids
  

• Internal contamination: Contact REAC/TS for guidance.
  
• 24-hr emergency number: 865-576-1005
  
• External contamination that cannot be removed
  
• Any patient with radiation exposure requires dose assessment and risk counseling.
  

• Emergency medical care takes precedence over decontamination:
  
  • No known case where a live, contaminated patient was so radioactive as to be an immediate hazard to emergency personnel
    
• Do not underestimate psychological impact of any incident involving “radiation”
  
• ALC can help differentiate ARS from psychosomatic illness: If vomiting is due to ARS, ALC should be low and falling over 4–8 hr
  

• Centers for Disease Control and Prevention. Emergency Preparedness and Response: Radiation Emergencies. Available at
  http://www.bt.cdc.gov/radiation/
  .
  
• National Library of Medicine’s Radiation Emergency Medical Management (REMM) website Online, downloadable, and mobile apps. Available at
  http://www.remm.nlm.gov/
  .
  
• Oak Ridge Institute for Science and Education. Radiation Emergency Assistance Center/Training Site (REAC/TS). Available at
  http://orise.orau.gov/reacts/
  .
  
• 24-hr emergency radiation injury response line: (865) 576-1005 (ask for REAC/TS).
  

See Also (Topic, Algorithm, Electronic Media Element)