Toxicology - faculty at Chemeketa

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Transcript Toxicology - faculty at Chemeketa

1
Toxicology,
Alcohol & Drug Abuse
2008
Types of Toxicological
Emergencies

Unintentional
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Dosage errors
Idiosyncratic reactions
Childhood poisoning
Environmental exposure
Occupational exposure
Neglect and exposure
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Intentional poisoning/overdose
• Chemical warfare
• Assault/homicide
• Suicide attempts
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Use of poison control centers
Oregon Poison Control
1-800-452-7165
Evaluation of the poisoned patient
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Scene Size-up
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
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Where are you?
Who’s around you?
Is there any potential danger?
Any evidence of pill bottles, used needles,
etc.
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History
• Provides a working diagnosis;
notoriously unreliable
• What - samples
• How much
• How
• When
• Why
• What else
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Physical exam

Vitals
• Airway
• Stridor
• Snoring
• Vomitus
• Gag reflex
• Risk of aspiration
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• Breathing evaluation
• Baseline RR
• Quality of respirations
–Shallow; need early ventilatory
support
–Deep; underlying hypoxemia or
metabolic acidosis
• Early - noncardiogenic pulmonary
edema
• Later - ARDS
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• Circulation
• Baseline pulse rate and BP
– Hypotension common
– Hypertension occasionally; serious ie
CVA
• ECG monitoring
– Tachyarrhythmias common; not usually
serious perfusion problem
– Bradyarrhythmias uncommon; more
serious underlying metabolic problem
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
Temperature
• Baseline temp.
• Hypothermia and hyperthermia
frequently accompany poisons
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Neuro complications
• Altered level of consciousness (AMS)
frequent
• Seizures one of most common
• Mild drowsiness
• Agitation
• Hallucinations
• Coma
• Medullary depression
• Cardiopulmonary depression
• Death
• Confused, combative
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Underlying disease states
• Asthma, COPD etc. increased risk for resp.
compromise
• Underlying cardiac disease increased risk for
severe arrhythmias.
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Supportive care
• Prevent or limit respiratory, cardiac,
neurologic complications
• Oxygen,
• IV
• ECG
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Respiratory complications
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Airway protection
ET or NT intubation
Bronchodilator therapy prn
Positive pressure ventilation prn
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Cardiovascular complications
• Appropriate antiarrhythmics
• Atropine
• Pacing
• Fluid challenge for hypotension
• Vasodilators for hypertension
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Neurologic complications
• Anticonvulsants; diazepam prn
• Chemical restraints only compounds
intoxication and may precipitate
catastrophic cardiopulmonary
complications
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Routes of absorption
• Ingestion
• Inhalation
• Injection
• Absorption
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Ingestion

Most common route
• Assessment findings
• What?
• When?
• Quantity?
• Alcohol?
• Self-treatment?
• Psychiatric care?
• Weight?
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Physical examination
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Skin
Eyes
Mouth
Chest
Circulation
Abdomen
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General management considerations
• Prevent Aspiration
• RSI?
• Fluids & Drugs
• GI decontamination
• Syrup of Ipecac
– Reduces absorption by @ 30%
– Interferes with activated charcoal
• Gastric lavage
– 36-40 Fr. orogastric tube
– After 1-2 hrs post ingestion questionable
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• Activated charcoal
• Agent of choice
• Adsorbs molecules of chemicals on its
surface
• Reduces absorption by @ 50%
• Dose 1 g/kg
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Cathartics
• Sorbitol, mag sulfate, mag citrate
• Speed up motility
• Studies show they don’t positively
affect patient outcome
• Liquid stools
• Dehydration, electrolyte imbalances
occur
• Administration of activated charcoal 2030 min. prior to gastric lavage doubles
effectiveness
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How do people poison
themselves?
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They Inhale it
• Paint, other hydrocarbons
• Carbon monoxide
• Ammonia
• Chlorine
• Freon
• Toxic vapors, fumes, aerosols
• Mace, mustard gas
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What do they look like?

Primarily respiratory
• Tachypnea, cough, hoarseness, stridor, dyspnea,
retractions, wheezing, chest pain or tightness, rales,
rhonchi
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Cardiac:
• Dysrhythmias
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CNS
• Dizziness, H/A, confusion, seizures, hallucinations,
coma
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Now what?
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Be safe!
Remove pt. From environment
Exam
Provide supportive care
Contact Poison Control and follow
directions
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They inject it
• IV drug abuse – more later
• Venomous bites and stings
• Bees, hornets, yellow jackets, wasps, ants
(only females)
• Spiders, ticks, other arachnids; scorpions
• Snakes
• Marine animals; jelly fish, stingrays,
anemones, coral, fish
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Ticks/Lyme Disease
Frequently requires Antibiotics
(Amoxicillin, Zithromax)
Tick generally must be attached for
24-48 hours
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• Results in immediate & delayed reactions
• Immediate reaction
– Rash
– Fever
– Malaise
– Fatigue
– H/A
– Muscle & joint aches
– Sore throat
– Sinus infection
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• Delayed reaction
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Chronic malaise/fatigue
Muscle pain/joint pain with/without arthritis
Neuropathy
Tremor
Bell’s palsy
Meningitis
Vision problems (double vision, photophobia)
Vestibular problems
Seizures
Cardiac symptoms
N/V
Immune suppression
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Hymenoptera (Bee stings, Wasp
stings, Ants)
• Bumblebees, Sweat bees, Honeybees; Hornets,
Yellow jackets; Fire ants, Harvester ants
• Type of reaction
• Local;
• Toxic; 10 or more stings
– N/V/D, light-headedness, syncope, H/A, fever,
drowsiness, muscle spasms, edema, seizures
– Sx subside w/in 48 hrs
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Bees and Bugs
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Systemic/anaphylactic:
• The shorter the onset, more severe the
reaction
• Initial sx: itching eyes, facial flushing,
generalized urticaria, dry cough
• Sx intensify; chest or throat constriction,
wheezing, dyspnea, cyanosis, abdominal
cramps, N/V/D, vertigo, chills, fever, shock,
loss of consc.
• Reaction can be fatal in 30 min.
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Bees and Bugs
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Delayed reaction
• Serum-sickness-like sx; fever, malaise, H/A,
urticaria, lymphadenopathy appears 10-14 days
later.
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Dx: difficult
• Honeybees; leaves it’s stinger with venom sac
attached
• Yellow Jackets: nest in ground
• Wasps: under eaves or windowsills
• Southern US Fire Ants; groupings of 3-4 stings
and pustules
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Bees and Bugs
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Tx:
• Scrape honeybees stinger out; don’t squeeze;
remove quickly
• Wash sting sites with soap and water
• Ice packs
• Benadryl, Prednisone
• Epinephrine 1:1000 0.3 - 0.5 mg sq if systemic
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Brown Recluse Spiders
(Fiddleback spider)

Southern, midwestern states
• Tennessee, Arkansas, Oklahoma, Texas,
Hawaii, California
• 15mm long. 6 eyes in a circle
• Lives in dark, dry locations
• Violin-shaped markings on back
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Does it
hurt?
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Usually painless
Bites occur at night
Local reaction
• Initially, small erythematous macule surrounded by a
white ring
• Over next 8 hours, localized pain, redness, swelling
• Tissue necrosis over days > weeks
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Chills, fever, N/V, joint pain, DIC
 Tx: Diphenhydramine; supportive
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Black Widow spiders
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Live in all parts of continental US
Found in woodpiles or brush
Female spider bites
• Orange hourglass on black abdomen
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Does it hurt?
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Immediate localized pain, redness, swelling.
Progressive muscle spasms of all large muscle groups
can occur
N/V, sweating, seizures, paralysis, decreased level of
consciousness.
Management: Supportive care;
• Consider Diazepam
• 2 – 10 mg IVP
• or Calcium gluconate
• 0.1 – 0.2 mg/kg of 10% solution.
• Monitor B/P
• Antivenin is available
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Scorpion stings
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All species can sting, =
localized pain
Only bark scorpion has
caused fatalities
• Mostly in Arizona,
California, Nevada, New
Mexico, Texas.
• Move mostly at night
• Venom stored in bulb at end
of tail
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Does it hurt?
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Venom acts on nervous system
• Burning, tingling effect
• Gradually progresses to numbness.
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Systemic effects
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Slurred speech, restlessness
Hyperactivity in 80% of children
Muscle twitching, seizures
Salivation, abdominal cramping, N/V
Management: Supportive
• Apply constricting band above wound site –
watch band – occludes lymphatic flow only
• Avoid analgesics; may increase toxicity
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Snakebite
• 8000 bites/yr - mortality is @
50/yr
• N. Carolina has highest %
• Peak months July, August
6am - 9 pm
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Pit Vipers
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Cottonmouth, rattlesnake, copperhead
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Indentation 1/2-way between eye and nostril
Hollow, retractable fangs
Vertical pupils
Triangular head
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Pit Vipers (cont.)
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Venom contains enzymes that may destroy
proteins, other tissue components; destroys
RBCs, affects blood clotting
Death from shock possible in 30 minutes
• Most occur 6-30 hours
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Pit Vipers (cont.)
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S/S: Fang marks, swelling and pain
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Weakness, dizziness, faintness
Sweating/chills
Thirst, N/V, Diarrhea,
Tachycardia, hypotension
Bloody urine
Tx: Keep pt. Supine
• Immobilize limb
• Maintain extremity in neutral position
• DO NOT apply constricting bands, Ice, etc.
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Coral snakes
• Distinct pattern of red
and black bands wider
than interspaced yellow
rings
• “Red on yellow, kill a
fellow”/coral snake
• “Red on black, venom
lack”/harmless snake
•Venom
•Affects coagulation
•Affects endothelium of
vessels
•Paralyzes activity of white
blood cells
•Neurotoxins A & B affect
nervous system; esp.
cardiorespiratory centers
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Coral Snakes (cont.)
• May be NO effects for 12-24 hours
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Localized numbness, weakness, drowsiness
Ataxia, slurred speech, excessive salivation
Paralysis of tongue, larynx
Drooping eyelids, double vision, dilated pupils
Abdominal pain, N/V
Hypotension, Respiratory failure
Seizures
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Coral Snakes (cont.)
• Size of victim important; condition of victim
will seriously affect outcome
• Location very important; bites on head and
trunk 2-3x more dangerous; bites on upper
extremities more serious than lower.
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Coral Snakes (cont.)
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Tx:
• Wash wound with copious amounts of water
• Apply compression bandage, keep extremity at
level of heart
• Immmobilize limb
• Transport for antivenin
• Do NOT apply ice, cold pack, freon sprays, or
incise wound
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Marine Animal
Injection
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Jellyfish, Coral, Sea urchins, Sting rays
 Secondary infections
 S/S: intense local pain, swelling
• Weakness, N/V
• Dyspnea, tachycardia
• Hypotension, shock
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Tx: Supportive care
• Consider a constricting band between heart, & wound;
occlude lymphatic flow only
• Heat or hot water
• Meat tenderizer
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Poisoning By Absorption
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Surface absorption
• Poisonous plants; ivy, sumac, oak
• Organophosphates
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Now What?
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Management considerations
• Remove pt. from environment
• Wear protective clothing
• Remove pt. clothing
• Initiate supportive measures
• Contact poison control
• Soap and water
• Decontaminate eyes with 15-30 min. Water
flush
• Supportive care
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Cholinergics
• Pesticides (organophosphates, carbamates)
• Nerve agents (sarin, Soman)
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Cholinergics (cont.)
• Findings
• SLUDGE
• Headache, Dizziness, Weakness, Nausea
• Bradycardia, wheezing, bronchoconstriction,
myosis, coma, convulsions, diaphoresis
• Management
• Decontamination
• Airway and ventilation
– Aggressive airway management
• Circulation
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Cholinergics (cont.)
• Pharmacological
• Atropine 2 – 5 mg IV q 15-30 min. until vitals
improve
• Pralidoxime chloride (2-PAM)
• Diazepam 2 – 10 mg IV for seizure control
• Activated charcoal – if ingested & gag reflex intact
• Transport considerations
• Protect self
• Notify receiving hospital
• May require decontamination outside ED
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Caustic substances

Acids, alkalis
• 12,000 exposures/yr
• 150 major complications/deaths
• Plumbing liquids
• Cause tissue coagulation, necrosis
• S/S - Acids: pH <2
• Eschar at burn site
• Local burns to mouth, throat
• Esophagus usually not damaged
• Stomach lining injured
• Immediate, severe pain
• Acidemia
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Alkali's: pH > 12.5
• Induce liquefaction necrosis
• Pain often delayed
• Cause perforation, bleeding, inflammation of
central chest structures
• W/in 2-3 days, complete loss of protective
mucosal tissue
• S/S:
• Facial burns, pain in lips, tongue, throat,
gums
• Drooling, trouble swallowing
• Hoarseness, stridor, SOB
• shock
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Tx:
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Aggressive, rapid
Prevent injury to rescuers
Airway management critical
Cricothyrotomy
Don’t use activated charcoal
Rapid transport
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Hydrofluoric Acid
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Used to etch glass
 Extremely toxic
 Penetrates deeply into tissues; inactivated only by
contact with calcium; settles in tissues as salt
• Causes total disruption of cell functioning, bone
destruction

S/S: burning at site of contact, SOB, confusion,
palpitations, muscle cramps
 Tx: Supportive: Immerse affected limb in ice
water with Mag. Sulfate or calcium salts
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Hydrocarbons
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Organic compounds;
• Kerosene, turpentine, mineral oil, chloroform, etc.
• Lighter fluid, paint, glue, lubricants, solvents, aerosol
propellants.

S/S:
• Burns, wheezing, dyspnea, slurred speech, ataxia,
obtundation
• Foot and wrist drop with numbness, tingling
• Cardiac dysrhythmias

Tx: Rarely serious – call poison control
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Tricyclic antidepressants

Narrow therapeutic index
• Amitrriptyline, Elavil, amoxapine,
clomipramine, doxepin, imipramine,
nortriptyline

S/S: dry mouth, blurred vision, urinary
retention, constipation, confusion,
hallucinations, hyperthermia, respiratory
depression, seizures, tachycardia,
hypotension, heart block, wide QRS,
Torsades de pointes

Tx: Sodium Bicarbonate, 1 mEq/kg
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MAO Inhibitors
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Atapryl, Eldepryl
 Relatively unpopular
• Narrow therapeutic index
• Serious interactions with red wine, cheese

Symptoms may not appear for up to 6 hours
• Headache, agitation, restlessness, tremor
• Nausea, palpitations, tachycardia, hypertension,
hyperthermia, bradycardia, hypotension, coma, death

No antidote available; tx life-threatening sx.
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Hallucinogens
• LSD, PCP, peyote, mushrooms, jimson weed,
mescaline
• “Psychedelic” - visual or tactile
• PCP
• Ketamine still used
• Powdered or solution; added to tobacco or
marijuana
• Onset in 2-5 min.; Peak effect in 15 min.
• Elimination half-life about 7 h - 3 days.
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LSD
• Blotter acid, sugar cubes, gelatin
• Sx in 1/2 - 1 hr; peak in 2 hrs (paranoia may
occur), acute psychosis may persist for days
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• Morning Glory
• Mescaline/Peyote
cactus
• 6-12 buttons required
to produce
hallucinogenic effects
• N/V, blurred vision,
hypertension,
tachycardia
• Effects peak at 2 hrs,
last for 6-12 hrs
• Religious ceremonies
• Tx with rest and
reassurance
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Mushrooms; psilocybin or ibotenic acidmagic mushrooms
• Common in US; pacific NW, texas, florida, hawaii
• Religious ceremonies since aztec
• Eaten raw, brewed in soup or tea, or dried
• GI discomfort in 15-30 min. N/V
• Effects last from 4-12 hrs
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• Nutmeg; common in
foods and herbal
remedies
• Myristicin is major
component
• 10-50 g of fresh nutmeg
(2-9 whole nutmegs)
• Sx in 3-6 hrs; N/V,
abdominal pain
• Cold extremities with
weak pulses shallow
respirations; sx resolve
in 24 hr with supportive
care
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• Designer amphetamines
• Adam, Eve, Ecstasy
• effects are drug and dose
Dependent
– Severe psychomotor agitation
– Disorders of thought process
– Hypertension, seizures, DIC,
ARDS, death
• Management supportive
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
Marijuana
• Cannabis sativa; marijuana and hashish
• Medicinal qualities in china > 4000 years
ago
• Today; glaucoma and chronic pain
• Most commonly used illicit substance after
alcohol and tobacco
• THC levels peak about 8 min after
inhalation, and 45 min. after ingestion.
Effects last 2-6 hrs.
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Narcotics

Heroin, methadone,
morphine, codeine,
meperidine, hydromorphone
(Dilaudid), hydrocodone
(Percodan)
• Street heroin cut with quinine,
lactose, sucrose, mannitol, talc,
procaine, baking soda.
• Effects include drowsiness,
euphoria, miosis, decreased
respiration, N/V
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Withdrawal
• Piloerection, lacrimation, yawning, rhinorrhea,
sweating, nasal stuffiness, myalgia, vomiting,
abdominal cramping, diarrhea, irritable,
hyperactive, confused
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• Narcotic overdose
• Cardinal findings; pinpoint pupils, hypoventilation
• Tx: Airway, ventilation, circulation
• Naloxone, 0.4-2.0 mg/0.01 mg/kg in child, SQ,
IM, IV, ET; effective in 1-2 min.
• Naloxone acts as antagonist at opiate receptor sites
• Overdose often mixed
• Serum half-life of Narcan is 1 hr with action
duration of 2-3 hr. (methadone half-life 72 hr).
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Complications of narcotic abuse
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Skin ulcers or lesions
nonpitting edema of extremities
Infection
Abscesses, Cellulitis, Thrombophlebitis
Endocarditis
Malaria (1929)
Tetanus (1876) esp. female, subcu injectors
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• Hepatic complications; most common
• GI complications
• Ilius
• Fecal impaction
• CNS complications
• Meningitis
• Spinal abscess
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Cocaine

Most common cause of drug related deaths
• Plant alkaloid found in coca plant. Leaves are
crushed with a hydrocarbon solvent followed
by extraction of alkaloid with sulfuric acid
• Smoked, snorted, or injected
• Crack is almost pure cocaine vaporizes at high
temp.
• Absorbed from all sites; mucous membranes,
GI tract, respiratory tree.
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Cocaine
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Smoked, injected, snorted, swallowed
Intensity & duration depends on route
1997 – 1.5 million Americans use
Drug most frequently involved in ED visits
Often used with Valium, Ativan, Heroin as
upper/downer combo
Adolescents combine Cocaine, Marijuana,
Alcohol
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Short-term effects
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Pleasure
Increased alertness
Paranoia
Vasoconstriction
Myocardial damage
Dysrhythmias
Death
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Long term effects
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Severe depression
 Loss of energy
 Damage to
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Heart
Lung
Brain
kidneys
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Cocaine (cont.)
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•
•
Intranasal admin peak effect in 1/2 hr
GI peak effect in 90 min.
IV and inhalation peak at 30 seconds to 2 min.
Tachycardia, hypertension, hyperthermia,
agitation, seizures are common.
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Cocaine (cont.)

AMI common; onset immediate > 24 hr.
• Coronary artery spasm, thrombosis, atrial and
ventricular arrhythmias, aortic rupture, CHF, QRS
widening

Spontaneous pneumothorax and
pneumomediastinum possible 2ndary to deep
breath holding
 CVA
 OB risks
 Renal failure
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Cocaine (cont.)
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Topical cocaine

Management
• Sedation, control of hyperthermia and seizures,
fluids.
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Amphetamines &
amphetaminie-like drugs
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•
•
•
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Benzedrine
Dexedrine
Ritalin
Midol
Vicks inhaler
Bronkaid tabs
Alka-Seltzer plus, Allerest, Contac, Dexatrim,
Dimetapp, Novahistine tabs, Extra-strength Sinutab,
Triaminic
• Actifed, Drixoral, Novahistine, Sudafed
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Amphetamines (cont.)
• First synthesized in 1887, but not
commercially available until 1932
• Similar to epinephrine, norepinephrine

Effects:
• Restlessness, hyperactivity, repetitive
behavior, anorexia, sleep reduction
• Rapidly absorbed from GI tract; peak levels
within 1 hr.
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Amphetamines (cont.)

Toxicity:
• Diaphoresis, extreme restlessness, repetitive
and bizarre behavior, coma, intracranial
hemorrhage, flushing, tachycardia,
hypertension, arrhythmias, MI, N/V/D
• Abrupt withdrawal rarely life-threatening.
Depression, increased appetite, cramps, N/D,
HA.
• Care supportive
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Methamphetamines
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Barbiturates
• First introduced as sedative in 1903. Currently
used to treat seizures, induction of anesthesia,
treatment of ICP
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•
•
•
Methohexital
Phenobarbital
Secobarbital
Primadone
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Barbiturates (cont.)


Barb. intoxication mimics alcohol
intoxication. Rule of thumb; 10x hypnotic
dose can produce severe toxicity.
Treatment: ET, gastric lavage, IV, diuresis,
Hemodialysis
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Benzodiazepines

Commonly used for anxiety, insomnia,
seizures, Alcohol withdrawal, conscious
sedation, general anesthesia.
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Xanax
Librium
Klonopin
Tranxene
Valium
Dalmane
Ativan
Versed
Halcion
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Benzodiazepines (cont.)

Predominantly CNS effects, well absorbed
from GI tract. IM injection is unpredictable
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Benzodiazepines (cont.)

Most serious toxicity occurs in ingestion of other
agents or parenteral administration.
 CNS effects;
• Drowsiness, dizziness, slurred speech, confusion,
ataxia, intellectual impairment.

Mgmt:
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•
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•
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Dextrose, thiamine, naloxone
Do not induce vomiting
Give activated charcoal
Gastric lavage
Monitor closely
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Cyanide

Potent cellular toxin; as little as 50 mg may
cause death.
• Extract of bitter almonds/cherry laurel leaves,
extracts of apricot, cherry, peach pits
• Silver polish
• Prolonged exposure to IV nitroprusside
• Burning of synthetics and wool, silk, vinyl,
polyurethane

Several hours exposure (<50 ppm) can cause sx
 Recovery is rapid after removal.
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
Exposure to 100 ppm may be fatal in 30 min.
 Sx:
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•
•
•
•
•
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Severe dyspnea,
Loss of consc., Seizures,
Arrhythmias,
HA,
Drowsiness,
Paralysis,
Pulmonary edema,

Bright red retinal vessels, smell of bitter
almonds important clues.
 Tx: amyl nitrite for inhalation, 10 ml of 3%
solution of sodium nitrite for IV infusion.;
Give 300 mg, followed by 12.5 g of sodium
thiosulfate.
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Drug abuse
• Epidemiology
• Incidence
• Morbidity/mortality
• Risk factors
• Prevention
• Psychological issues
• Psycho-social issues
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Drug abuse (cont.)

Pathophysiology of long term drug abuse
• End-organ damage
• Brain, liver, heart
• Malnutrition
• Habituation/dependence/addiction
• Tolerance
• Withdrawal syndromes
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Alcoholism - Ethanol
• Incidence
• Morbidity/mortality
– 42% traffic fatalities, 69% drownings, 23%
suicides
– 100,000+ deaths/yr
• Risk factors
• Prevention
• Psychological issues
• Psycho-social issues
98
Alcoholism (cont.)

End-organ damage
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•
•
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•
Brain
Liver
Heart
Bone
Pancreas
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Alcoholism –
Clinical Manifestations
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Altered Immunity
Anorexia
Dysrhythmias
Coma
Irritability and disorientation
Muscle cramps
Poor wound healing
Seizures
Tremor and ataxia
100
Alcoholism (cont.)



Malnutrition
Withdrawal syndrome
Wernicke’s encephalopathy (disorder of
the brain)
101
Alcoholism –
Body System Disturbances

Fluid and electrolyte from diuresis

GI disorders (bleeds, esophageal varices)

Liver (cirrhosis)

Pancreatitis

Cardiac and skeletal muscle myopathy

Immune suppression

Trauma (suppressed clotting factors)
102
Prehospital concerns

Delirium Tremens (DT’s)
• Treat symptomatically
• Valium/Versed
• Rehydration
103
Wernicke-Korsakoff’s syndrome
• Personality; psychosis, polyneuritis,
disorientation, muttering delirium, insomnia,
illusions, hallucinations
• Classic triad; ataxia, ophthalmoplegia
(nystagmus and 6th nerve palsy), and altered
mental status; also, hypothermia, coma,
hypotension
104
Methanol
• Antifreeze, paint solvent, Sterno, gasoline
additives
• Life-threat even with small amount; 30 ml of
100% methanol lethal;
• Converted in liver to formaldehyde to formate
= cellular hypoxia.
• S/S: visual sx-photophobia, blurred vision,
dilated pupils; CNS depression; abd. Pn; N/V;
metabolic acidosis. Onset 1 hr - 72 hrs
105
Ethylene Glycol
• Colorless, oderless, sweet-tasting, nonvolatile
liquid
• Detergents, paints, pharmaceuticals, polishes,
antifreeze, lysol spray, coolants
• Toxicity due primarily to accumulation of toxic
metabolites.
• CNS sx 1-12 hr later: Ataxia, nystagmus,
seizures, hallucination, coma
106
Ethylene Glycol (cont.)



Cardiopulmonary sx 12-72 hrs later:
Tachycardia, tachypnea, mild HTN,
pneumonia, pulmonary edema, cardiac
failure
Renal failure w/in 24-72 hrs
Tx: Gastric lavage, Alcohol, calcium
chloride
107
Salicylates - aspirin
(acetylsalicylic acid)
• Oil of Wintergreen (methyl salicylate)
• Darvon, Percodan, Fiorinal

Directly stimulates respiratory centers in
brainstem, = respiratory alkalosis.

Causes mobilization of glycogen stores
and inhibits gluconeogenesis, =
hyperglycemia, normoglycemia,
hypoglycemia
108
Salicylates - ASA

S/S:
• GI irritation, Upper GI bleeding, persistant
vomiting
• Mixed respiratory and metabolic acidosis
• Confusion, lethargy, convulsions, respiratory
arrest, coma, brain death, cardiac toxicity,
significant hyperthermia, pulmonary edema
109
Salicylates - ASA

Toxic doses
• Peak serum levels in 18-24 hrs, although
toxic levels within 6 hours.
• Therapeutic levels, salicylate mainly cleared
by hepatic metabolism
• Toxic levels, renal excretion is major route
of elimination
• 150-300 mg/kg = mild-moderate toxicity;
hyperpnea, vomiting, diaphoresis, tinnitus,
acid/base disturbances
110
Salicylates - ASA

Tx:
• Activated charcoal
• IV fluids
• D50
• Hemodialysis
111
Acetaminophen poisoning
(APAP)
• Tylenol, Datril
• Poisoning may result in fatal hepatic necrosis
• Therapeutic dose 15 mg/kg q 4-6h (children)
max daily dose 80 mg/kg
• 325-1000 mg q 4 h (adults) max daily dose 4 g
• Eliminated primarily by hepatic metabolism
• Mechanism of toxicity unclear; a highly
reactive metabolite is thought to cause hepatic
necrosis by binding to protein macromolecules
112
Acetaminophen poisoning
(APAP)

Toxic doses
• 140 mg/kg in children
• 7/5 g in adults

Toxicity:
• Stage I: 1/2 - 24 h
• N/V, Anorexia, malaise, pallor, diaphoresis
• Stage II: 24-48 h
•
•
•
•
Transient clinical improvement
RUQ pain with liver enlargement, tenderness
Pancreatitis
Oliguria
113
Acetaminophen poisoning
(APAP)

Toxicity:
• Stage III: 72-96 h
• GI sx reappear, persist, or worsen
• Jaundice
• SGOT, SG
• Stage IV: 4 d - 2 weeks
• Resolution or progressive hepatic failure
114
Overdose guidelines
Alcohol – thiamine, D50W
 Cocaine – Benzodiazepines

• Beta blockers absolutely contraindicated





Narcotics/opiates – naloxone
Amphetamines – benzodiazepines, haldol
Hallucinogens – benzodiazepines, haldol
Benzodiazepines – flumazenil
Barbiturates – forced diuresis, alkalinization of
urine
115
Bye-Bye now~
116