-
Toxicology
Study of the detection, chemistry, pharmacology and antidotes of toxic substances.
-
Toxin
Any chemical (drug, poison or other) that causes adverse effects on an organism that is exposed to it.
-
Stats
- 4 million poisonings occur annually
- Ten percent of all ER visits
- 70% of accidental poisonings under 6 y/o
-
Routes of Exposure
- Ingestion
- Inhalation
- Absorption
- Injection
-
Ingestion
Entry of a substance through GI tract
-
Inhalation
Entry of substance through respiratory tract
-
Absorption
Entry of substance through skin or mucous membranes
-
Organophosphates
Phosphorous-containing organic chemicals
-
Injection
Entry of substance through break in skin
-
Decontamination
Process of minimizing toxicity by reducing amount of toxin absorbed
-
Principles of Decontamination
- Reduce intake
- Reduce absorption
- Enhance elimination
-
Gastric Levage
Removing and ingested poison by repeatedely filling and emptying the stomach with water or saline via a gastric tube
-
Activated Charcoal
A powder, usually premixed with water, that will absorb (bind) some poisons and help prevent them from being absorbed into the body
-
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
-
Antidote
A substance that will neutralize a specific toxin or counteract its effect
-
Toxidrome
A toxic syndrome, a group of typical signs and symptoms associated with exposure to a particular toxin
-
CO Sources
Endogenous Sources: Within the body, normal levels
Exogenous Sources: Outside sources, cars, heaters, etc.
Methylene chloride: Industrial solvent, breaks into CO
-
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
-
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
-
CO-Oximetry
A system capable of providing measurements of oxygen saturation (SpO2), carboxyhemoglobin (SpCO), methemoglobin (SpMET), and pulse.
-
Acid
A substance that liberates hydrogen ions (H+) when in solution
-
Alkali
Substance that liberates hydroxyl ions (OH-) when in a solution, strong base.
-
Therapeutic Index
Maximum tolerated dose divided by minimum curative dose of a drug, range between curative and toxic dosages, also called therapeutic window.
-
Exotoxin
Soluble poisonous substance secreted during growth of bacterium
-
Enterotoxin
Exotoxin that produces GI symptoms and diseases such as poisoning
-
Substance Abuse
Use of pharmacological substance for purposes other that medically defined reasons
-
Addiction
Compulsive, overwhelming dependence on a drug. May be physiological or psyhcological or both.
-
Tolerance
Need to progressively increase dose of a drug to reproduce initial effect
-
Withdrawal
When the patient's body reacts severely when deprived of the substance
-
Drug Overdose
Poisoning from pharmacological substance in excess of usual prescribed dose or that the body can tolerate
-
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.
|
|