Medical Countermeasures and Casualty Care
CBRN casualty care is standard casualty care plus a small number of high-yield specific measures.
Nerve agents
The toxidrome is cholinergic. Atropine antagonizes muscarinic effects and is titrated to drying of secretions and resolution of bronchospasm and bradycardia; it does not reverse nicotinic effects such as fasciculations or weakness. An oxime such as pralidoxime reactivates the inhibited enzyme and must be given early, before enzyme aging makes it useless; aging rates differ by agent. Benzodiazepines treat seizures. Autoinjectors allow rapid self- or buddy-administration. Succinylcholine should be avoided in nerve-agent casualties because of prolonged paralysis.
Other agents
Cyanide: hydroxocobalamin is preferred, with sodium thiosulfate as an alternative. Vesicants: no antidote for sulfur mustard, so care is supportive; dimercaprol is used for lewisite. Radiological: potassium iodide blocks thyroid uptake of radioiodine only if given before or soon after exposure; Prussian blue enhances excretion of cesium; DTPA chelates plutonium and americium. Biological: post-exposure antibiotics for anthrax, antitoxin for botulism, and vaccination where indicated.
Triage
CBRN incidents often shift triage priorities and create an expectant category. Patients who are ambulatory but contaminated still need decon before entry to a treatment area; the treatment area itself stays in the cold zone.
Rule of thumb
Airway, breathing, circulation, then the antidote. For nerve agents, titrate atropine to secretions, not to heart rate, and give the oxime early.