Overview
This lecture covers the types, symptoms, and management of common poisonings, including corrosives, medications, and carbon monoxide.
Types of Poisoning
- Corrosives are classified as alkaline (e.g., drain cleaners, bleach, button batteries) or acidic (e.g., pool cleaners, battery acid).
- Medication overdoses commonly involve acetaminophen, NSAIDs, psychiatric drugs, and blood pressure medications.
Clinical Manifestations
- Medication overdoses show amplified medication side effects (e.g., extreme hypotension with BP meds).
- Corrosives and acids cause burning, oral redness or burns, painful swallowing, vomiting, and drooling.
Management and Supportive Care
- Remove or inactivate the poison, provide organ support, administer antidotes, and facilitate elimination.
- Identify the ingested substance to select appropriate interventions.
- For eye exposure, flush with water/saline for up to 15 minutes while patient blinks.
- Call poison control for guidance and information sharing—no HIPAA violation.
Antidotes and Toxidromes
- Toxidrome: pattern of symptoms from specific poison classes.
- Antidotes include physostigmine (anticholinergics), atropine/pralidoxime (cholinergics), naloxone (opioids).
- No true antidote for sympathomimetic toxicity; treat agitation/seizures with benzodiazepines.
Decontamination Methods
- Dilution: give 8 oz. milk/water (adults), 2–8 oz. for children.
- Gastric lavage ("stomach pumping") if within 1 hour of ingestion; left lateral position, use warm saline, send aspirate for toxicology.
- Dialysis may be needed for circulating toxins or to correct imbalances.
- Activated charcoal is effective for some toxins, not corrosives; give orally/NG tube in small doses to prevent vomiting.
Monitoring & Support
- Strict intake/output (I&O) and urinary catheterization for kidney monitoring.
- Continuous cardiac monitoring and electrolyte/acid-base balance assessment.
- Avoid inducing vomiting to prevent further esophageal damage.
Carbon Monoxide Poisoning
- Elevated carboxyhemoglobin (>15%) marks poisoning; normal is <1.5%.
- Symptoms: CNS effects (dizziness, confusion, seizures, coma), palpitations.
- Skin color and pulse oximetry are unreliable indicators.
- Move patient to fresh air, give 100% oxygen via non-rebreather, monitor carboxyhemoglobin levels.
- Prevent chilling, avoid smoking, and follow up for possible permanent neurological damage.
Key Terms & Definitions
- Corrosive — Substance that causes tissue damage via chemical action.
- Toxidrome — Group of symptoms/signs characteristic of a specific class of toxins.
- Antidote — Substance that counteracts a poison.
- Gastric lavage — Stomach pumping to remove ingested toxins.
- Carboxyhemoglobin — Hemoglobin bound to carbon monoxide, indicating CO exposure.
Action Items / Next Steps
- Review class table on acid-base imbalances from poisonings.
- Memorize key antidotes and their indications.
- Practice identifying toxidromes and their management steps.