Chapter 22:Overview and Management of Toxicology

May 21, 2025

Chapter 22: Toxicology Lecture Notes

Overview of Toxicology

  • Toxicology is the recognition and management of different poisonings.
  • Focus on carbon monoxide poisoning and nerve agent poisonings.
  • Importance of contacting poison control.
  • Review of anatomy, physiology, pathophysiology, assessment, and management of different types of poisonings:
    • Inhaled
    • Ingested
    • Injected
    • Absorbed
    • Alcohol intoxication and withdrawal

Statistics

  • Acute poisoning affects over 2 million people yearly.
  • Poisoning deaths are rare, but increasing due to drug abuse in adults.
  • Child-resistant caps have reduced poisoning in children since the 1960s.

Key Definitions

  • Poison: Substance causing chemical damage to body structures or functions.
  • Toxin: Poisonous substance by bacteria, animals, or plants.
  • Substance Abuse: Misuse of a substance for a desired effect.
  • Overdose: Excessive amount of a toxic substance.

Responsibilities and Observations

  • Recognize poisoning, ensure scene safety, and observe surroundings.
  • Signs and symptoms vary with specific agents.

Types of Poisons and Symptoms

  • Opioids/Opiates: Respiratory arrest, sedation, hypotension.
  • Methamphetamine/Cocaine: Hypertension, tachycardia, agitation, hyperthermia.
  • Sedatives: Slurred speech.
  • Anticholinergics: Speeding up effects, e.g., atropine, diphenhydramine.

Mnemonics for Symptoms

  • SLUDGE for organophosphates (nerve gas):
    • Salivation, Lacrimation, Urination, Defecation, Gastric upset, Emesis, Muscle twitching

Patient Assessment Questions

  • What was ingested, exposure time, amount, antidotes, patient weight.
  • Handle suspicious materials safely.

Routes of Poison Entry

  • Inhalation: Fresh air, oxygen, possible hazmat intervention.
  • Absorption: Remove contaminated clothing, flush skin.
  • Ingestion: Activated charcoal use (if protocol allows).
  • Injection: Calming patient, transport.

Poison Control and Treatment

  • Contact poison control for guidance.
  • Activated charcoal (rare in EMS) for some ingestions, depending on local protocols.
  • Treat symptoms like nausea, vomiting, shock, and maintain ABCs.

Substance Abuse and Effects

  • Alcohol: Depressant, decreases responses, risk of addiction, withdrawal symptoms.
  • Opioids: Pain relief but risk of dependence and overdose, treated with Narcan.
  • Sedative-hypnotic drugs: Alter consciousness, risk of drowsiness, peacefulness.
  • Inhalants: Dangerous solvents causing heart sensitivity.
  • Hydrogen Sulfide: Toxic gas, decontamination needed.

Stimulants and Hallucinogens

  • Sympathomimetics: Cocaine, methamphetamine, euphoria, hypertension.
  • Marijuana: Euphoria, difficulties in thinking, possible anxiety in high doses.
  • Hallucinogens: LSD, PCP, altered reality, intense sensory experiences.
  • Anticholinergic and Cholinergic Agents: Overdose management with specific antidotes (atropine and pralidoxime).

Food and Plant Poisonings

  • Common bacterial causes: Salmonella, botulism.
  • Plant poisonings: Recognize and transport plants to medical facilities for identification.

Ensure all incidents involving poisons are documented thoroughly, including symptoms, treatments, and poison types where possible.

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