Medical Aspects of Chemical Warfare (2008) - The Black Vault

Medical Aspects of Chemical WarfareTable 21-7Managing Pulmonary Agent ExposuresAgent Symptoms TreatmentChlorine• Lacrimation• Rhinorrhea• Conjunctival irritation• Cough• Sore throat• Hoarseness• Laryngeal edema• Dyspnea• Stridor• Acute respiratory distress syndrome• Pulmonary edemaPhosgene • Transient irritation (eyes, nose,throat, and sinus)• Bronchospasm• Pulmonary edema• Apnea• HypoxiaDecontamination: copious water irrigation of the skin, eyes, and mucosalmembranes to prevent continued irritation and injurySymptomatic care (no antidote): warm/moist air, supplemental oxygen,positive pressure oxygen for pulmonary edemaBronchospasm: beta-agonists (albuterol)Severe bronchospasm: corticosteroids (prednisone; also used forpatients with history of asthma but use unproven)Analgesia and cough: nebulized lidocaine (4% topical solution) ornebulized sodium bicarbonate (use unproven)Decontamination: wash away all residual liquid with copious water,remove clothingSymptomatic care: maintain patient’s airway, breathing, and circulation,hydrate, positive pressure oxygen for pulmonary edemaBronchospasm: beta-agonists (albuterol), corticosteroids INH/IV,Furosemide is contraindicatedHypoxia: oxygenINH/IV: inhaler/intravenous solutionData source: Burklow TR, Yu CE, Madsen JM. Industrial chemicals: terrorist weapons of opportunity. Pediatr Ann. 2003;32(4):230–234.Clinical PresentationCyanide intoxication is an uncommon cause ofchildhood poisoning; 96 the pediatric population (< 19years old) represented only 7.8% of cyanide poisoningsreported in 2000. 67 Because signs of toxicity are similarto carbon monoxide poisoning (which accounts for thelargest group of poisoning deaths among children),clinicians must have a high index of suspicion to makea diagnosis of cyanide poisoning. 98,99 Rotenberg describesa typical toxidrome induced by cyanide, whichincludes a rapid progression from hyperpnea, anxiety,restlessness, unconsciousness, seizures, apnea, and finallydeath. 96 Skin, blood, and fundi may be cherry redupon physical examination 96–99 because of the inabilityof mitochondria to extract oxygen (Exhibit 21-5).Laboratory FindingsArterial blood gases can provide clues to verifycyanide exposure. Classic cases present with severemetabolic acidosis, elevated anion gap, and high lactateconcentrations. 96 Impaired cellular respiration leadsto a high oxygen content in venous blood 96,98 ; thus, areduced arterial-venous oxygen saturation differencesuggests cyanide poisoning. Blood cyanide levels areconfirmatory but delay the diagnosis, which mustbe based on the initial clinical presentation. 96–98 Analmond-like odor on the breath may indicate that aperson has been exposed to cyanide, but up to 40% ofthe general population is unable to detect this odor. 96Pediatric VulnerabilityChildren are especially vulnerable to cyanide attacksbecause of their higher respiratory rates and surface-tovolumeratios. 96 Additionally, cyanide liquid is rapidlyabsorbed in greater amounts when it comes in contactwith children’s immature skin barriers. 96 The initialsymptoms described in a case report of 10 children whoingested cyanide included abdominal pain, nausea,restlessness, and giddiness. 99 Cyanosis and drowsinesswere also noted, but the signature cherry-red skin colorwas not reported. Postmortem examination of two childrenthat died following exposure showed bright redblood and congested tissues. These children consumedpowder packets of potassium cyanide mixed in water,while the other 8 children only licked the powder. Thesurvivors were managed with aggressive supportivecare, including gastric lavage, oxygen, and IV fluids.TreatmentIn the United States, the mainstay of treatment forcyanide poisoning consists of supportive treatmentand use of a multistage antidote kit that contains674