Volume 3 Chapter 8

  1. Toxicology
    Study of the detection, chemistry, pharmacology and antidotes of toxic substances.
  2. Toxin
    Any chemical (drug, poison or other) that causes adverse effects on an organism that is exposed to it.
  3. Stats
    • 4 million poisonings occur annually
    • Ten percent of all ER visits
    • 70% of accidental poisonings under 6 y/o
  4. Routes of Exposure
    • Ingestion
    • Inhalation
    • Absorption
    • Injection
  5. Ingestion
    Entry of a substance through GI tract
  6. Inhalation
    Entry of substance through respiratory tract
  7. Absorption
    Entry of substance through skin or mucous membranes
  8. Organophosphates
    Phosphorous-containing organic chemicals
  9. Injection
    Entry of substance through break in skin
  10. Decontamination
    Process of minimizing toxicity by reducing amount of toxin absorbed
  11. Principles of Decontamination
    • Reduce intake
    • Reduce absorption
    • Enhance elimination
  12. Gastric Levage
    Removing and ingested poison by repeatedely filling and emptying the stomach with water or saline via a gastric tube
  13. Activated Charcoal
    A powder, usually premixed with water, that will absorb (bind) some poisons and help prevent them from being absorbed into the body
  14. Whole Bowel Irrigation
    Administration of polyetylene glycol continuously at 1-2 L/hr through a nasogastric tube until the effluent is clear or objects are recovered
  15. Antidote
    A substance that will neutralize a specific toxin or counteract its effect
  16. Toxidrome
    A toxic syndrome, a group of typical signs and symptoms associated with exposure to a particular toxin
  17. CO Sources
    Endogenous Sources: Within the body, normal levels

    Exogenous Sources: Outside sources, cars, heaters, etc.

    Methylene chloride: Industrial solvent, breaks into CO
  18. CO Pathophysiology
    • Limits O2 transport
    • Inbits O2 tranfer
    • Causes tissue inflammation
    • Causes reduces cardiac function
    • Increases activation of nitric oxide
    • Causes vasodilation
    • Induces free-radical formation
  19. S/S of CO Poisoning at Different Levels
    <15-20% Mild- H/A, n/v, dizzness, blurred vision

    21-40% Moderate- Confusion, syncope, CP, dyspnea, tacycardia, tachypnea, weakness

    41-59% Severe- dysrhythmias, hypotension, cardiac ischemia, palpitations, respiratory arrest, pulmonary edema, seizures, coma, cardiac arrest

    >60% Fatal
  20. CO-Oximetry
    A system capable of providing measurements of oxygen saturation (SpO2), carboxyhemoglobin (SpCO), methemoglobin (SpMET), and pulse.
  21. Acid
    A substance that liberates hydrogen ions (H+) when in solution
  22. Alkali
    Substance that liberates hydroxyl ions (OH-) when in a solution, strong base.
  23. Therapeutic Index
    Maximum tolerated dose divided by minimum curative dose of a drug, range between curative and toxic dosages, also called therapeutic window.
  24. Exotoxin
    Soluble poisonous substance secreted during growth of bacterium
  25. Enterotoxin
    Exotoxin that produces GI symptoms and diseases such as poisoning
  26. Substance Abuse
    Use of pharmacological substance for purposes other that medically defined reasons
  27. Addiction
    Compulsive, overwhelming dependence on a drug. May be physiological or psyhcological or both.
  28. Tolerance
    Need to progressively increase dose of a drug to reproduce initial effect
  29. Withdrawal
    When the patient's body reacts severely when deprived of the substance
  30. Drug Overdose
    Poisoning from pharmacological substance in excess of usual prescribed dose or that the body can tolerate
  31. Delirium tremens (DTs)
    Disorder found in habitual and excessive users of alcoholic beverages after cessation for 48-72 hours. Visual, tactile, auditory disturbances. Death in severe cases.
Card Set
Volume 3 Chapter 8
Volume 3 Chapter 8