Caustics – Spoon Feed Version

June 15, 2020

Written by Clay Smith

Spoon Feed
Caustic injury is common and dangerous. This treatment algorithm can help us manage these patients safely.

Why does this matter?
Whether oropharyngeal, GI, eye, or dermal, caustic injuries by alkali, acids, or other agents are commonly seen in the ED. Injury from alkaline detergent pods has been increasingly seen in children. We need to be expert in the approach and management of these patients. I learned a lot from reading this review article.

Back to basics

Common Alkali

• Ammonium hydroxide – General cleaner and grease remover

• Sodium hydroxide or potassium hydroxide – Drain opener, oven cleaner, hair relaxer, grease remover

• Sodium hypochlorite (a.k.a. bleach) – swimming pool chlorinator

Common acids

• Acetic acid – Food pickling, photographic stop bath

• Hydrochloric acid – Toilet bowl cleaner, mold and mildew remover

• Oxalic acid – Metal polish

• Phosphoric acid – Rust remover

• Selenous acid – Gun bluing agent

• Sulfuric acid – Drain opener, large lead-acid batteries

Miscellaneous or unique caustics

• Cationic detergents (e.g., benzalkonium chloride…side note…why is this in albuterol?) – Surface cleaner, preservative

• Hydrofluoric acid – Rust and graffiti remover

• Hydrogen peroxide – Surface and food cleaner

• Phenol – Surface disinfectant

• Zinc chloride – Soldering flux

Credit: The above list of common alkali, acids, and other caustics was adapted from Table 1 of the article.

Pathophysiology

• Acids with pH <2 and alkali with pH >12 usually cause injury.

• Alkali cause saponification, liquefaction, and deeper injury.

• Acids cause coagulation necrosis and generally less deep injury, though not always.

• Hydrofluoric acid is unique and may cause direct cellular injury, bind calcium and magnesium, cause hypocalcemia/hypomagnesemia, and may cause hyperkalemia from extensive tissue necrosis.

Clinical Impact

• Pain, drooling, stridor, and respiratory difficulty are common with ingestion. Changes in voice and difficulty handling secretions is ominous.

• Perforation, peritonitis, and mediastinitis may all occur with severe ingestion and injury.

• Eye injury or dermal injury may also result.

Management

• Assess the airway, stabilize, and decontaminate (remove clothing, use copious irrigation with water – after brushing off dry chemical). Up to 50% of adult intentional ingestions may need to be intubated.

• Examine for external chemical burn marks, but don’t be falsely reassured if children lack face or oropharyngeal marks; one third may still have injury on endoscopy.

• See the management algorithm proposed below.

• Endoscopic grade of injury has to do with the depth and severity and determines management, so it is actually important for us to know in the ED.

  • Grade 0-1 means no or mild injury (redness) – these patients do well.

  • Grade 2A may have friability, hemorrhage, or superficial ulcers. These patients also do well, with low risk for stricture.

  • Grade 2B, on the other hand has deeper ulceration and is more likely to form stricture.

  • Grade 3A adds necrosis; 3B extensive necrosis; 4 perforation. These are all bad if not fatal.

• For grade 2B alkali ingestions, these authors advocate for the Usta protocol (see text with figure below), which includes a glucocorticoid. There is debate about this amongst toxicologists.

Disposition/Prognosis

This is determined by severity of injury. Follow the algorithm. Patients with deeper injury are at greater risk for stricture and subsequent malignancy.

Source
Ingestion of Caustic Substances. N Engl J Med. 2020 Apr 30;382(18):1739-1748. doi: 10.1056/NEJMra1810769.

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