A 3-year-old boy is brought to the emergency department by his pregnant mother after developing severe abdominal pain within the past hour and having several episodes of vomiting. The patient's vomit is black and red in color. Blood pressure is 80/50 mm Hg, pulse is 140/min, and respirations are 30/min. On physical examination, he is irritable and lethargic. Examination shows a normal oropharynx. Cardiopulmonary examination is normal. The abdomen is soft and mildly tender at the epigastrium; there is no hepatosplenomegaly. The extremities are cool to the touch. Laboratory results are as follows: Chest x-ray is normal. Abdominal imaging shows several radiopaque tablets in the stomach. Intravenous normal saline is started. Which of the following is the best next step in management of this patient?

Question

A 3-year-old boy is brought to the emergency department by his pregnant mother after developing severe abdominal pain within the past hour and having several episodes of vomiting.  The patient's vomit is black and red in color.  Blood pressure is 80/50 mm Hg, pulse is 140/min, and respirations are 30/min.  On physical examination, he is irritable and lethargic.  Examination shows a normal oropharynx.  Cardiopulmonary examination is normal.  The abdomen is soft and mildly tender at the epigastrium; there is no hepatosplenomegaly.  The extremities are cool to the touch.  Laboratory results are as follows:  Chest x-ray is normal.  Abdominal imaging shows several radiopaque tablets in the stomach.  Intravenous normal saline is started.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d1d7_cbd0_bc81_21bb3154daae_MD0003_00 This child has abdominal pain, hematemesis, and anion gap metabolic acidosis, findings consistent with acute iron poisoning. Radiopaque tablets in the stomach suggest an accidental ingestion of his mother's prenatal vitamins, which contain significantly more iron than most vitamin preparations. Excessive iron is toxic to the gastrointestinal mucosa, causing abdominal pain, vomiting, diarrhea, and bleeding (hematemesis/melena). Vomitus and stool may appear black or green from disintegrating iron tablets. Hypovolemia from gastrointestinal losses may lead to shock, a potential complication in this patient with hypotension and tachycardia. Anion gap metabolic acidosis (= sodium − [chloride + bicarbonate] = 140 − [104 + 18] = 18 in this patient) results from hydrogen ion production during iron absorption and increased lactic acid production in shock. First-line treatment of acute iron poisoning is aggressive volume resuscitation. Excessive iron is treated with deferoxamine, a chelating agent that binds free iron, forming a complex that can be renally excreted. Because iron is rapidly taken up by various organs (eg, myocardial cells, hepatocytes), deferoxamine must be administered early to be effective. Severe, untreated acute iron poisoning may lead to distributive shock (due to systemic vasodilation), cardiogenic shock (due to iron-induced myocardial injury), hepatic necrosis, and death. (Choice A) Calcium gluconate treats hyperkalemia, which may present with muscle weakness, palpitations, and arrhythmias. This patient has none of these symptoms and has a normal potassium level. (Choice C) Hemodialysis removes free circulating iron and may be considered on occasion if deferoxamine fails to improve symptoms of iron poisoning. (Choice D) N-acetylcysteine is used in acetaminophen toxicity, which presents acutely with nausea, vomiting, and abdominal pain. Hematemesis and radiopaque tablets on x-ray would not be seen. (Choice E) Naloxone reverses narcotic overdose, which presents with somnolence and respiratory depression. This patient is lethargic but has a normal respiratory rate. In addition, radiopaque tablets would not be seen. (Choice F) Oral succimer can be used as a chelating agent in lead poisoning, which can present with abdominal pain, vomiting, and lethargy. However, anion gap metabolic acidosis is not seen. (Choice G) Warfarin (a vitamin K antagonist) toxicity can present with severe hemorrhage (eg, hematemesis, intracranial bleed) and is treated with exogenous vitamin K (phytonadione). However, warfarin is not radiopaque. Educational objective: Acute iron poisoning can occur after accidental ingestion of prenatal vitamins and presents with abdominal pain, hematemesis, shock, and anion gap metabolic acidosis. Deferoxamine is the primary therapy. References: Successful treatment of severe iron intoxication with gastrointestinal decontamination, deferoxamine, and hemodialysis. (http://www.ncbi.nlm.nih.gov/pubmed/23635030)

A 3-Year-Old Boy Is Brought to the Emergency Department by His