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16 Cards in this Set
- Front
- Back
What are caustics?
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Corrosive agents that have the potential to cause tissue injury on contact
Most are acids and alkalis. Other caustic agents include phenol, formaldehyde, iodine and H2O2 |
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What are alkalis?
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Agents that accept protons
NaOH, KOH, NH3 are examples |
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What are acids?
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Acids are proton donors
Examples are HCl, HF and H2SO4 |
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List some common household caustic agents
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Drain cleaner
Oven cleaner Rust remover Toilet bowl cleaner Swimming pool cleaner |
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How do acids damage tissues?
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Through coagulation necrosis that forms an eschar and limits further penetration. This causes pain on immediate contact which limits ingestion.
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How do alkalis cause damage?
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Through liquefaction necrosis, fat saponification and protein disruption. This mechanism allows further penetration of the product through the tissue. It does not cause pain immediately so more is often ingested.
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What are the 4 steps of caustic damage?
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1 - necrosis
2 - vascular thrombosis 3 - superficial layers slough off (2-5 days) 4 - granulation tissue forms (1 week-months) |
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How are caustic injuries classified?
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The same as burns based on appearance on endoscopy.
1st - edema and hyperemia 2nd - a - noncircumfrential and b - near circumfrential 3rd - necrotic mucosa or perforation Increase grade correlates with the development of strictures |
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What needs to be assessed on a patient with a caustic ingestion?
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A - assess for edema and airway burns watching specifically for stridor, drooling and dysphonia (secure airway!)
BC - assess for hemodynamic instability (hypotension, tachycardia, fever and acidosis have a poor prognosis). Peritoneal signs suggest perforation. Tracheal necrosis often kills |
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When does stricture develop secondary to a caustic ingestion?
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2-8 week
Presents with dysphagia and food impaction The earlier the symptoms, the worse the prognosis |
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Does acid or alkali ingestion have a worse prognosis?
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Acids have higher mortality possibly due to systemic absorption of the acid that causes hemolysis and renal failure.
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What is the workup for caustic ingestion?
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Chest x-rays (peritoneal and mediastinal air)
Abdominal CT (perforation) ABG (acidosis Endoscopy* (with caution) |
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What special consideration must be taken with HF acid?
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Cardiac monitoring to assess for QTc, torsades and other ventricular dysrhythmias
Causes profound hypocalcemia. If unstable give CaCl empirically. If skin exposure put CaGluconate gel on it and consult poison control for advice on intradermal or intraarticular injection |
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When is endoscopy indicated for caustic ingestions? When isn't it?
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Indicated - caustic ingestion with NO suspicion of perforation and a patent lumen with no necrosis. Should be done between 12-24 hours post ingestion (too early miss extent of injury, too late more hazardous due to wound softening)
Contraindicated in possible or known perforation |
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What is the treatment for caustic ingestion?
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A - early if any signs of compromise. Blind intubation is contraindicated. Consider fiberoptic or surgical airway
B - watch for missed pneumoperitoneum / mediastinum C - IV fluids. Consider water/milk within a few minutes, nasogastric aspiration within a few minutes. Surgical exploration if peritonitic E - assess for dermal/ocular exposure. Trash contaminated clothing Other - Steroids and antibiotics are controversial. May delay presentation of complications |
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What is the antidote for Betadine ingestion?
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This can cause severe GI injury. Give starch or milk to convert iodine to iodide.
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