Resident Manual of Trauma to the Face, Head and Neck

Packaging Act of 1970 mandated childproof container caps and packag- ing. Injury can range from mild mucosal irritation to death, depending

on the quantity and type of substance ingested. A. Categories of Caustic Materials

Caustic materials may be classified into three different categories, as shown below. Table 10.2 presents some examples of these categories of caustic materials.

Table 10.2. Categories and Examples of Caustic Materials Acids (pH < 7) Alkali (pH > 7)

Bleach (pH ~7)

Sodium hypochlorite Calcium hypochlorite

Toilet bowl cleaner Battery fluid Sulfuric acid

Lime Laundry detergent Clinitest ® tablets Hair-relaxing agents*

*Hair-relaxing agent packaging is not mandated by the U.S. Food and Drug Administration to be sold in child-safe packaging. Their pleasant odor and colorful tubs unintentionally attract children, leading to an increased incidence of ingestion over the last decade. 1. Acids (pH <7) Acids (pH <7) cause coagulation necrosis with eschar formation, which limits its penetration to deeper tissues. Esophageal damage is less likely due to the protection afforded by the slightly alkaline pH of the esopha- gus and resistance of the squamous epithelium to acids. Gastric injury may occur at a slightly higher incidence due to pooling and prolonged contact from reflex pylorospasm. The acidic pH in the stomach can also heighten the injury. 2. Alkali (pH >7) Alkali (pH >7) agents cause liquefaction necrosis, which breaks down the cellular membranes, allowing deeper penetration into tissues. Tissue damage continues until the alkali is neutralized by its reaction with the tissues, resulting in significant injury. Areas of narrowing are at greater risk for injury (e.g., cricopharyngeus, aortic arch, left mainstem bronchus, diaphragmatic hiatus). 3. Bleach (pH ~7) Bleach (pH ~7) is an esophageal irritant that causes minimal morbidity or mortality.

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