Approximately 1.1 million cases of ingestion of a toxic substance by a child less than six years of age were reported to poison control centers in 1998. This number is thought to represent approximately 25 percent of all such incidents. Shannon reviews the management strategies of poisoning in children.
Substances commonly ingested by children less than six years of age include cosmetics, cleaning products, analgesics and cold preparations (see Table 1). Data from 1995 through 1998 reveal that prescription and over-the-counter medications accounted for 52 percent of the deaths from poisoning during this period. Substances associated with the greatest risk of death include cocaine, anticonvulsants, antidepressants and iron supplements.
|Agent ingested||Number of children|
|Cosmetics and personal care products||568,856|
|Cough and cold preparations||278,460|
*—Number of cases from 1995 through 1998. Information from Litovitz TL, et al., in 1995, 1996, 1997 and 1998 annual reports of the American Association of Poison Control Centers Toxic Exposure Surveillance System. The annual reports were published in the American Journal of Emergency Medicine.
Reprinted with permission from Shannon M. Ingestion of toxic substances by children. N Engl J Med 2000;342:187.
The initial step in obtaining treatment is usually a telephone call by the parents to a physician or a poison control center. For children brought to an emergency department, physical assessment and stabilization of vital signs is the initial treatment step. Toxicology screening is rarely required because the ingested substance is usually known.
The next step is to decide on the need for gastric emptying to decrease absorption in the small intestine. Table 2 summarizes the three interventions used for gastrointestinal decontamination following ingestion of a toxic substance.
|Ipecac syrup||Age 6 to 9 months: 5 mL||Prolonged vomiting,|
|Age 10 to 11 months: 10 mL||aspiration|
|Age 1 to 12 years: 15 mL|
|Activated charcoal||1 g per kg (maximum: 50 to 60 g)||Aspiration, tracheal instillation, constipation, vomiting|
|Magnesium citrate in 6 percent suspension||4 mL per kg||Dehydration, hypermagnesemia|
|Sorbitol||1 to 2 g per kg||Hypernatremic dehydration|
|Polyethylene glycol (whole-bowel irrigation)||Age 9 months to 5 years: 500 mL per hour||Vomiting, bloating, abdominal cramping|
|Age 6 to 12 years: 1,000 mL per hour|
Reprinted with permission from Shannon M. Ingestion of toxic substances by children. N Engl J Med 2000;342:188.
Ipecac syrup is the preferred agent for inducing emesis. This product contains cephaline and emetine, which stimulate gastric sensory centers linked to the vomiting center in the brain. Use of ipecac should be considered in children who have ingested a potentially toxic substance in the preceding hour. Emesis usually begins within 20 minutes of administration of ipecac syrup.
The author notes that the efficacy of ipecac syrup has not been proved. He cites a study suggesting that no benefit is derived from administration of ipecac syrup between five and 30 minutes after ingestion of the toxic substance. Clinical studies have shown that a mean of 30 percent of a toxin is recovered when ipecac syrup is administered within one hour of ingestion.
Use of ipecac syrup should be avoided in certain situations, such as when calcium channel blockers, beta blockers, digitalis and clonidine are the ingested substances. It also should not be used when a corrosive agent or a substance that produces a rapid change in consciousness has been ingested. It is not indicated for use in children less than six months of age.
A second method of gastric decontamination is gastric lavage. With a large-bore (24 to 32 French) tube in place, room-temperature aliquots of normal saline (10 to 15 mL per kg) are instilled through the tube and then aspirated. Lavage is continued until the stomach contents are clear. As with the use of ipecac syrup, the safety and efficacy of gastric lavage has been challenged. Gastric lavage has been found to retrieve less than 30 percent of the toxin when performed one hour after ingestion. According to the author, data suggest that the two methods have similar efficacy.
The use of adsorptive agents decreases the amount of the toxic agent available for absorption by the gastric mucosa. While several agents are available, activated charcoal is the most broadly effective adsorbent. The binding surface of available forms of activated charcoal ranges from 1,000 to 3,000 m2 per g. It is capable of enhancing elimination of some toxins that have already been absorbed, such as theophylline, phenobarbital and carbamazepine. It is not effective for alcohol, hydrocarbons, metals and minerals. When activated charcoal is given at a fixed dosage of 1 g per kg, it can reduce absorption of toxins by up to 75 percent. The main concern with the use of activated charcoal is vomiting, which occurs in approximately 15 percent of children and increases the risk of aspiration, empyema and pneumothorax.
The third type of intervention is administration of cathartic agents to increase gastrointestinal motility and hasten the expulsion of the toxin. The two most commonly used agents are magnesium citrate and sorbitol. Both of these products are osmotic agents and are considered to be safe for use in children. They can be used with activated charcoal.
The author notes that the incidence of childhood poisoning has dropped significantly in the past 50 years. He attributes this decline to federal regulation of products and product safety, child-resistant containers and safe storage of toxic substances in the home and elsewhere. The safety and efficacy of smaller dosages of activated charcoal are currently under investigation for at-home administration and likely will replace ipecac syrup as a safer and more effective alternative.