Chapter 28
Toxicology
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28-1
Objectives
28-2
What Is a Poison?
• Poison
• Poisoning
• Toxin
• Antidote
• Poison Control Center
28-3
Routes of Entry
28-4
Toxidromes
• Signs, symptoms, and characteristics
that often occur together in toxic
exposures
• Categories
– Sympathomimetic
– Cholinergic
– Anticholinergic
– Opioid
– Sedative/hypnotic
28-5
Sympathomimetic Toxidrome
Signs/Symptoms
Examples
•
•
•
•
• Amphetamines,
methamphetamines
• Cocaine
• Phencyclidine (PCP)
• Ecstasy
• Caffeine
• Pseudoephedrine
Agitation
Rapid breathing
Increased heart rate
Increased blood
pressure
• Fever
• Seizures
• Sweating
28-6
Cholinergic Toxidrome
Signs/Symptoms
Examples
• Altered mental status • Organophosphate
• Decreased or
and carbamate
increased heart rate
insecticides
• SLUDGEM
• Some mushrooms
Salivation
• Nerve agents
Lacrimation (tearing)
Urination
– Sarin gas
Defecation
Gastrointestinal distress
Emesis (vomiting)
Miosis (pupil
constriction)
28-7
Anticholinergic Toxidrome
Signs/Symptoms
Examples
•
•
•
•
•
•
• Antihistamines
– Benadryl
• Jimson weed
• Tricyclic
antidepressants
Confusion
Hallucinations
Agitation
Coma
Blurred vision
Warm, flushed, dry
skin
• Dilated pupils
– Amitriptyline (Elavil)
– Desipramine
(Norpramin)
– Nortriptyline
(Aventyl, Pamelor)
28-8
Opioid (Narcotic) Toxidrome
Signs/Symptoms
Examples
• Altered mental
status
• Coma
• Slow or absent
breathing
• Slow heart rate
• Low blood pressure
• Constricted pupils
•
•
•
•
Morphine
Codeine
Heroin
Diphenoxylate
(Lomotil)
• Meperidine (Demerol)
• Methadone (Dolophine)
• Propoxyphene
(Darvon)
28-9
Sedative/Hypnotic Toxidrome
Signs/Symptoms
• Slurred speech
• Hallucinations
• Confusion
• Coma
• Respiratory depression
• Low blood pressure
• Pupil dilation or
constriction
• Blurred vision
• Dry mouth
• Decreased temperature
• Staggering walk
Examples
• Barbiturates
– Phenobarbital
• Benzodiazepines
– Diazepam (Valium)
• Alcohol
• GHB (a date-rape
drug or “liquid x”)
28-10
Commonly Misused
and Abused Substances
28-11
Key Terms
•
•
•
•
•
•
Substance abuse
Substance misuse
Tolerance
Addiction
Withdrawal
Overdose
28-12
Stimulants
• Examples
– Cocaine
– Amphetamines, methamphetamines
– PCP
– Caffeine
– Nicotine
• Increase mental and physical activity
• May produce violent behavior
28-13
Depressants
• Examples
– Alcohol
– Barbiturates
– Narcotics (opiates)
– Benzodiazepines
28-14
Depressants
Alcohol
• Slows mental and physical activity
• Affects judgment, vision, reaction time,
and coordination
• In large quantities, can cause death
28-15
Depressants
Alcohol
• Signs and symptoms of misuse or
abuse can mimic those of other
medical conditions
• Do not assume the patient is
intoxicated.
28-16
Depressants
Alcohol
• Alcohol withdrawal syndrome
• Delirium tremens (DTs)
28-17
Depressants
Barbiturates
• Prescribed to relieve anxiety, promote
sleep, control seizures, and relax
muscles
• Examples
– Secobarbital (Seconal)
– Phenobarbital (Luminal)
• Particularly dangerous when
combined with alcohol
28-18
Depressants
Narcotics
• Prescribed drugs used to relieve
moderate to severe pain, control
diarrhea, and suppress cough
• Narcotics include:
– Opium
– Opium derivatives
– Man-made compounds that produce
opium-like effects
28-19
Depressants
Benzodiazepines
• Prescribed medications used:
– To control anxiety and stress
– To aid sleep
– To relax muscles
– For sedation
– To control seizures
• Overdose can result in respiratory
depression and death
28-20
Hallucinogens
• Examples
– Lysergic acid diethyl amine (LSD)
– PCP (angel dust)
– Mescaline
• Produce changes in mood, thought,
emotions, and self-awareness
• Can also cause disruptive behavior
that can make the user dangerous to
himself and others
28-21
Designer Drugs
• Variations of federally controlled
substances that have high abuse
potential
• Can be injected, smoked, snorted, or
ingested
• Signs and symptoms unpredictable
• Overdose occurs frequently
28-22
Patient Assessment
28-23
Scene Size-Up
• When responding, you may or may not
know the substance(s) involved
• Remember scene safety in all
circumstances
• Observe the patient’s environment for
clues:
– Unusual odors
– Smoke or flames
– Open medicine cabinet
– Open or overturned containers
– Syringes or other drug paraphernalia
28-24
Primary Survey
Mental Status
• Many toxic exposures result in
mental status changes
• Anticipate seizures
28-25
Primary Survey
Airway
• Look
– Burns around the mouth
– Blisters of the lips or mucous membranes
– Difficulty swallowing or drooling
• Listen
– Stridor
– Hoarseness
• Use airway adjuncts, suction as needed
28-26
Primary Survey
Breathing
• Be prepared to provide positivepressure ventilation
• Narrowing of lower airway may cause
wheezing
28-27
Primary Survey
Circulation
• Toxic exposures can affect heart rate
and blood pressure
– Increased or decreased heart rate
– Irregular heart rhythm
– Increased or decreased blood pressure
– Shock
28-28
•
•
•
•
•
Primary Survey
Priority Patients
Patients who give a poor general
impression
Patients experiencing difficulty
breathing
Patients with signs and symptoms of
shock
Unresponsive patients with no gag
reflex or cough
Responsive patients who are unable to
follow commands
28-29
Secondary Survey
• SAMPLE history
– Who, what, where, when,
why, how
• Vital signs and physical
exam findings (toxidrome)
can provide clues
28-30
Common Signs and Symptoms
of Poisoning
• Altered mental
status
• Difficulty
breathing
• Headache
• Nausea
• Vomiting
• Diarrhea
• Chest or
abdominal pain
• Sweating
• Seizures
• Burns around the
mouth
• Burns on the skin
28-31
Emergency Care
• Have trained rescuers remove patient from
source of poison
• Follow decontamination procedures
• Maintain an open airway
• Give oxygen
• Call a Poison Control Center as needed
• Bring containers, labels, or other evidence to
receiving facility
• Save vomitus
• Anticipate complications
• Ongoing assessments
28-32
Ingested Poisons
28-33
Ingested Poisons
• Signs and symptoms are
related to:
– The drug ingested
– The amount ingested
– The length of time since
the ingestion
28-34
Ingested Poisons
• Emergency care:
– Remove pills, tablets from patient’s mouth
– Maintain an open airway
– Give oxygen
– Consult medical direction about giving
activated charcoal
– Bring containers, labels, and other
evidence of suspected poisons to
receiving facility
– Transport
28-35
Activated Charcoal
• Activated charcoal can only bind a
drug that is not yet absorbed from the
gastrointestinal tract
28-36
Activated Charcoal
Actions
• Acts as an adsorbent
• Binds with many (but not all chemicals)
• Slows down or blocks absorption of the
chemical
28-37
Activated Charcoal
Indications/Dosage
• Indications
– Some ingested poisons
• Dosage
– 1 gram of activated charcoal per kilogram
of body weight
– Usual adult dose: 25 to 50 grams
– Usual infant/child dose: 12.5 to 25 grams
28-38
Activated Charcoal
Contraindications
• Patient has an altered mental status
• Patient is unable to swallow
• Medical direction does not give
authorization
• Patient has ingested acids or alkalis
28-39
Inhaled Poisons
28-40
•
•
•
•
•
•
•
•
Inhaled Poisons
Examples
Carbon monoxide • Hair spray
• Cleaning fluids
Carbon dioxide
• Correction fluid
Chlorine
• Nail polish remover
Ammonia
•
Glue,
rubber
cement
Propane
• Paint, paint thinner
Cyanide
• Lighter fluid
Freon
• Room deodorizers
Tear gas
• Felt marker pens
28-41
Inhalants
• “Huffing”
• “Sniffing”
• Sudden sniffing death syndrome
28-42
Inhaled Poisons
Signs/Symptoms
• Signs and symptoms depend on:
– The substance inhaled
– The amount inhaled
– The extent and duration of exposure
28-43
Inhaled Poisons
• Signs and
symptoms:
– History of
inhalation of toxic
substance
– Altered mental
status
– Difficulty
breathing
– Chest
pain/discomfort
– Cough
– Hoarseness
– Dizziness
– Headache
– Confusion
– Seizures
28-44
Inhaled Poisons
• Emergency care:
– Have trained rescuers remove patient from
poisonous environment
– Ensure scene safety
– Removed and discard contaminated
clothing
– Maintain open airway
– Give oxygen
– Bring containers/labels to receiving facility
– Transport
28-45
Injected Poisons
28-46
Injected Poisons
• Poisons that can be injected
include:
– Bee, wasp, and ant venom
– Spider, tick, and scorpion
venom
– Snake venom
– Drugs
28-47
Injected Poisons
• Signs and symptoms:
– Weakness
– Dizziness
– Chills
– Fever
– Abnormal heart rate or rhythm
– Nausea
– Vomiting
28-48
Injected Poisons
• Emergency care:
– Remove patient (and rescuers) from
environment
– Maintain an open airway
– Give oxygen
– Contact medical direction/Poison Control
Center to help determine potential toxicity
– Bring containers/labels to receiving facility
– Monitor for anaphylaxis
– Transport
28-49
Absorbed Poisons
28-50
Absorbed Poisons
• Examples of poisons that can be
absorbed include:
– Toxins from plants
• Poison ivy, poison oak, and poison sumac
– Pesticides
– Fertilizers
– Cocaine
– Chemical warfare agents
28-51
Absorbed Poisons
• Signs and symptoms:
– History of exposure
– Liquid or powder on patient’s skin
– Burns
– Itching
– Irritation
– Redness
28-52
Absorbed Poisons
• Emergency care:
– Remove patient from source of the poison
– Remove powder or residue from patient’s
skin
– Remove/discard contaminated clothing
– Maintain open airway, give oxygen
– If present, brush powder off the patient
– If exposure involves patient’s eye, flush
affected eye with clean water
– Transport
28-53
Questions?
28-54