A 3-year-old boy is brought to the hospital after being found in a storage shed struggling to breathe. His parents are unsure of what has happened and note that multiple chemicals are stored in the shed. Temperature is 36.6 C (98 F), blood pressure is 98/65 mm Hg, pulse is 58/min, and respirations are 40/min. Oxygen saturation is 86% on room air. On examination, the patient is lethargic; his body and clothes are soiled with vomit. The pupils are pinpoint bilaterally, and there is significant watering of the eyes. Auscultation of the lungs demonstrates widespread rhonchi with prolonged expiration. Muscle fasciculations are noted in the extremities. Following endotracheal intubation, which of the following is the most appropriate next step in management of this patient?

Question

A 3-year-old boy is brought to the hospital after being found in a storage shed struggling to breathe.  His parents are unsure of what has happened and note that multiple chemicals are stored in the shed.  Temperature is 36.6 C (98 F), blood pressure is 98/65 mm Hg, pulse is 58/min, and respirations are 40/min.  Oxygen saturation is 86% on room air.  On examination, the patient is lethargic; his body and clothes are soiled with vomit.  The pupils are pinpoint bilaterally, and there is significant watering of the eyes.  Auscultation of the lungs demonstrates widespread rhonchi with prolonged expiration.  Muscle fasciculations are noted in the extremities.  Following endotracheal intubation, which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d1d9_2b62_bc81_2fa3fafb2ac2_MD0003_00 This pediatric patient with respiratory distress after a presumed chemical exposure has signs of cholinergic toxicity, likely from exposure to an organophosphate pesticide. In organophosphate poisoning, acetylcholinesterase is rendered nonfunctional, leading to hyperstimulation of the muscarinic and nicotinic cholinergic receptors. Muscarinic stimulation leads to widespread, increased visceral smooth muscle tone and glandular secretions (mnemonic: DUMBELS-see table), whereas nicotinic activation leads to muscle fasciculations, weakness, and paralysis, which can lead to rapid respiratory failure. Initial management includes patient stabilization (ie, airway, breathing, circulation) and decontamination. This includes removal of exposed clothes, which can be contaminated both from topical chemical exposure and by vomiting/diarrhea after chemical ingestion. This should be followed by copious irrigation of the skin and/or eyes to prevent cutaneous absorption. Health care personnel should use personal protective equipment (ie, gloves, gown) and work in a well-ventilated examination room to prevent accidental exposure. To counteract the effects of organophosphate poisoning, atropine, a competitive inhibitor of acetylcholine at the muscarinic receptor, should be administered immediately. This is typically followed by pralidoxime, a cholinesterase-reactivating agent that reverses the nicotinic (neuromuscular) symptoms of poisoning. (Choice A) Physostigmine, an acetylcholinesterase inhibitor, is sometimes used to treat anticholinergic toxicity, which is characterized by flushing, anhidrosis, hyperthermia, mydriasis, and urinary retention. It would worsen this patient's condition. (Choices B and D) Obtaining an ECG and analyzing the QRS interval are critical in a tricyclic antidepressant overdose, which typically presents with altered mental status and anticholinergic signs (ie, flushed skin, mydriasis). Patients with a prolonged QRS (>100 msec) require treatment with sodium bicarbonate to prevent ventricular arrhythmias. (Choice C) Hemodialysis is sometimes used to treat toxic alcohol poisoning, which usually presents with altered mental status as well as vision changes (methanol) or flank pain and hematuria (ethylene glycol). It is not indicated in cholinergic toxicity. Educational objective: Organophosphates are acetylcholinesterase inhibitors that are primarily used as agricultural pesticides. Toxicity is characterized by signs of cholinergic excess (eg, miosis, bronchospasm, muscle fasciculations/weakness, diarrhea, vomiting, lacrimation) and can rapidly lead to respiratory failure. Management includes decontamination (removal of clothes, irrigation of skin) to prevent cutaneous absorption and treatment with atropine followed by pralidoxime.

A 3-Year-Old Boy Is Brought to the Hospital After Being