Background
• Cause tissue injury by acidic or alkaline chemical rxn
• pH <2 is considered strong acid, pH >12 considered strong base
• Severity of tissue injury determined by duration of contact, pH, concentration, type of substance (liquid vs. solid)
Approach
• Careful hx: Spec agent, amount, duration, pH, & timing of ingestion, coingestants
• Often a suicidal gesture; assess mental state as well as physical
• Rapid physical exam: Look for respiratory compromise, stridor, hoarseness, oropharyngeal burns, drooling, subcutaneous air, acute peritonitis (signs of perforation), hematemesis
• Do NOT induce emesis; reexposure could worsen injury
• Do NOT attempt to neutralize ingestions due to likelihood of causing exothermic rxn
ACID/ALKALINE INGESTIONS
History
• Alkaline: Ingestion of ammonia, cleaning agents: Drain, oven, swimming pool, dishwasher detergents, bleach, cement, hair relaxers
• Acid: Ingestion of battery liquid, toilet bowl cleaners, rust or metal cleaning products, drain cleaners, cement cleaning products
Findings
• Alkaline: Liquefactive necrosis – severe injury starts rapidly after ingestion, w/i min of contact, tissues that 1st contact alkali are most severely injured (oropharynx, hypopharynx, esophagus). Tissue edema occurs immediately, may persist for 48 h, progress → airway obstruction. Over 2–4 wk get scar tissue thickening → strictures (depends on depth of burn).
• Acid: Coagulation necrosis → desiccation → eschar formation; stomach most commonly affected, small bowel exposure possible. Eschar sloughs in 3–4 d, then granulation tissue development. Perforation after 3–4 d as eschar sloughs; gastric outlet obstruction if scar tissue contracts over 2–4 wk. Pyloric sphincter spasm may delay gastric emptying & ↑ contact time to 90 min.
• In hydrofluoric acid (HF) ingestion, ↓ Ca may lead to arrhythmias, sudden cardiac arrest
• Both may cause esophageal perforation
Evaluation
• pH of product & of saliva, CBC, Chem 7, ABG, baseline LFTs, UA, pre-op labs, tox screen; cardiac monitoring, ECG; x-rays, consider CT for extraluminal air
• Endoscopy if symptomatic, small child, AMS but not if e/o perforation, airway edema
Treatment
• Airway protection, large-bore IV access; surgical consultation, antiemetics
• Gastric lavage controversial
• Activated charcoal not helpful due to poor adsorption
• Dilution w/ small amts of water/milk may be beneficial if done w/i 30 min after ingestion
• Abx if e/o perforation, pain control
Disposition
• Admit to ICU if symptomatic