Nonmedicinal

a. Personal care products. Some substances may be irritating or corrosive, depending on concentration, molarity, and other factors. In general, serious esophageal injury is associated with ingestion of products with pH > 11.5. Alkaline corrosive ingestion may produce burns to oropharynx, upper airway, esophagus, and occasionally stomach. Spontaneous vomiting may occur. It is important to recognize that absence of visible oral burns does not reliably exclude presence of esophageal burns. Stridor, vomiting, drooling, and abdominal pain are associated with serious esophageal injury in most cases.

b. Cleaning agents. Serious injuries are associated with caustic substances with high pH. See preceding discussion.

c. Plants. Most plants have mild skin irritant effects or mild GI symptoms (eg, nausea, vomiting, diarrhea, or abdominal pain).

d. Pesticides. Two main groups of chemical are usually encountered: organophosphates (see earlier discussion of anticholinesterase syndrome, at III, A, 4) and carbamates. Carbamate syndrome may be indistinguishable from that seen after organophosphate poisoning. Generally, clinical effects are not as severe as those seen with organophos-phate poisoning; carbamates do not penetrate CNS as effectively as do organophosphates; thus, they produce more limited CNS toxicity. e. Hydrocarbons. Low-viscosity, highly volatile hydrocarbons (eg, kerosene, gasoline, liquid furniture polish) are associated with aspiration hazards. Parenchymal pulmonary injury, transient CNS depression or stimulation, and secondary effects of hypoxia, infection, pneumatocele formation, and chronic lung dysfunction can occur. Cardiac complications are rare.

C. Small, But Serious Pediatric Ingestions. Quantity of ingested substance in most cases is proportional to severity of induced toxicity. When possible, calculation of milligram-per-kilogram dose of ingestion is helpful to prognosticate outcome. In toddlers, however, a small dose can be lethal. For examples, see Table I—21.

D. Nontoxic Ingestions. Approximately 70% of all pediatric poisoning are nontoxic. Examples include oral antibiotics, antacids, chalk, crayons, hydrogen peroxide, and zinc oxide.

IV. Database. Onset of symptoms can be immediate or delayed for several hours or a few days due to latency of effect of toxin or slow release of active form. Signs and symptoms are variable and related to pharmacologic properties of toxin. Significant ingestions commonly affect vital signs, neuropsychiatric status, GI tract, and pupillary size and reactivity to light. Other less common manifestations are specific odors, skin discoloration, and disturbances of exocrine glands.

A. History Key Points. History is often inaccurate and should be interpreted cautiously. In case of suicidal attempt in a teenager or unresponsiveness where poisoning is considered, an investigative-type approach to history may be warranted. 1. Ingestion history. Initial, brief history should include product name, active ingredients, amount ingested, and time of ingestion.

TABLE I—21. PEDIATRIC POISONS AND LETHAL DOSES

Drug

Lethal Dose per Kg

Unit-Dose

Lethal Amount

Antimalarials

20 mg

500 mg

1 tab

ß-Blockers

-10 mg

25-100 mg/tab

1-2 tabs

Calcium channel blockers

15-20 mg

240 mg/tab

1 tab

Camphor

100 mg

1 g/tsp

1 tsp

Chlorpromazine

25 mg

200 mg/tab

1-2 tabs

Clonidine

< -1 mg

0.3-7.5 mg/tab

1 tab or patch

Imipramine

15 mg

150 mg/tab

1 tab

Methyl salicylate

200 mg

7 g/tsp

< 1 tsp

a. Obtain all prescription bottles and other containers when possible. Perform a pill count. Be sure bottles contain medications listed. Identify any unknown tablets.

b. Contact prescribing physician(s) or pharmacy as listed on bottles to determine previous overdoses or other medications patient may have available. Identify underlying medical and psychiatric disorders and medication allergies. Review past medical records.

c. Talk to patient's family and friends in the emergency department. if necessary, call patient's home to ask questions of others. Persons providing important elements of history should be identified in chart.

d. Search patient's belongings for drugs or drug paraphernalia. A single pill hidden in a pocket, for example, may provide the most important clue to diagnosis.

e. Have family members (or police) search patient's home, including medicine cabinet, clothes drawers, closets, and garage; this may also provide clues that enable diagnosis to be made. This step has added benefit of involving family in patient's care.

f. Estimate maximum possible intake. In case of prescription and over-the-counter medications, calculate milligram-per-kilogram dose of ingestion.

2. Review of systems. Focus on symptoms of vomiting, visual disturbances, palpitations, sweating, abdominal pain, breathing difficulty, and skin discoloration or rash.

3. Past medical history. Asthma, cardiac disease, or seizure disorder is particularly important.

Physical Exam Key Points. The following clinical observations provide clues for toxidromes and are crucial during management decision-making process.

1. Vital signs. Increase or decrease in temperature, heart rate, BP, or respiratory rate. Attention to pattern of breathing: slow shallow or rapid and deep. Provide 100% oxygen in case of respiratory distress.

2. Neuropsychiatry status. Lethargy and coma require administration of IV dextrose (0.5-1.0 g/kg or 2-4 L/kg of D25W) and naloxone (2 mg IV q2-5min until clinical response; to maximum of 10.0 mg). This is a therapeutic as well as a diagnostic measure. Treat agitation and seizure with benzodiazepines (IV diazepam, 0.1 mg/kg).

3. Airway. Assess presence of gag and cough reflex; if absent, endotracheal intubation is indicated.

4. Eyes. Assess pupillary size and reactivity to light.

5. Abdomen. Absence of bowel sounds may signal presence of ileus.

6. Musculoskeletal exam. Assess muscle tone; observe for tremors, weakness, nystagmus, or seizure.

C. Laboratory Data. Consider the following studies, depending on ingested substance and clinical circumstances. (Do not obtain workup for nontoxic ingestions.)

1. Blood chemistry. Obtain serum glucose level (including bedside test), ABGs, carboxyhemoglobin, methemoglobin, electrolytes, BUN, creatinine, liver function tests, serum osmolality, CBC, metabolic screening, and anion gap.

2. Toxicology screening. Obtain specific blood level of ingested or potentially ingested substance when pertinent. If time of ingestion is known, then proper timing of sampling is important.

3. Drug screening. Of limited use in immediate management. Useful to support clinical impression of ingestion of certain drug or class of drugs.

4. Other workup. Includes urine FeCl3 (for salicylates).

D. Radiographic and Other Studies. Abdominal x-ray can identify iron, lead-based paint chips, or ileus from opioids.

V. Plan. Figure I-6 outlines an algorithmic approach to the poisoned child.

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