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General Approach tothe Poisoned Patient
LTC Mike Miller, MD, FACEP
CPT Lisa M. Yungmann M.D.
Darnall Army Community Hospital
Government Services Chapter
American College of Emergency Physicians
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Why do we discuss toxicology?
In practice, toxicology makes up 5-
30% of your cases
Inservice and written boards, about 8%
Oral boards, about 15%
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But reallytoxicology is fun
Know common tox
presentations and
antidotes, and you
can save a life
The physiology and
science of toxicsubstances is cool
Theres always
some new drug to
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Poison facts
>2 million toxic exposures per year
More than half of exposures,
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Objectives
Supportive care is main means to
decrease morbidity and mortality
Learn about gastric decontamination
Learn and know all antidotes
Know toxidromes and treatment
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General Approach
ABCs of Toxicology
A-Antidotes and alter absorption (insome instances prior to airway-decontamination with
organophosphates to protect others, cyanide toxicity whereantidotes are lifesaving)
B-Basics; ABCs
C-Change metabolism (NAC, ethanol)
D-Distribute differently (calcium gluconate,O2)
E-Elimination (diuresis, dialysis, hemoperfusion)
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GI contamination
Charcoal-now procedure of choice if
appropriate substance. Major risk is
aspiration.
May use NG/OG tube or give orally.
If giving orally, assure patient is awakeand airway protected.
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Multidose Charcoal
Used with some select drugs
Used to interrupt enterohepaticrecirculation.
Do not use sorbitol with MDAC
Useful for: carbamazapine, theophylline,barbituates, salicylates, dapsone, depakote,
digoxin, quinine
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GI contamination-when charcoal
doesnt work
C-Caustics
H-Hydrocarbons
A-Alcohols
I-Iron
L-Lithium L-Lead(and other heavy
metals)
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Consider whole bowel irrigation
for:
Drugs where
charcoal can not be
used
Sustained release
preparations
Body packers
Large quantities of
toxic substances
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To lavage or not?
Controversial
Indicated for recent ingestions
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Are any lab values helpful?
ECG
Chem 7 Acetaminophen level
Serum osmolality
VBG (determine pH)
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Useful lab values
Calculate the anion gap
AG=Na-(HCO3+Cl) Causes anion gap:
AT MUDPILES (alcohols, toluene, methanol,
paraldehyde/phen phen, iron/INH, lactic acidosis,ethylene glycol, salicylates/strychnine)
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Useful lab values
Osmolar gap=measure serum
osmolality-calculated serum osmolality
Calculated=2Na+glucose/18+BUN/2+
ethanol/6
Causes Osmolar Gap:
ME DIE (methanol, ethanol, diuretic, isopropyl,ethylene glycol)
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Drugs to Dialyze-STUMBLE
S-Salicylates
T-Theophylline U-Urea
M-Methanol
B-Barbituates
L-Lithium
E-Ethylene glycol
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Case #1
A 19 y/o raver dropped off in your EDby his raving buddies after punching
the bouncer and trying to jump out ofhis friends car into the middle of theGW Parkway.
He is cursing and screaming BP 200/110, P 120, T 100.7, R 22,
O2 97% RA
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Case #1
The raver continues to curse and yell
He is diaphoretic, pupils dilated,piloerection is noted
What toxidrome is presented here?
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Sympathomimetic
Hypertension,
tachycardia,
diaphoresis,psychotic behavior
Tmt:
1.Benzos2.Benzos
3.Nitroprusside, phentolamine or
dexmedetomidine
4.Do NOT acidify urine
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Case#2
And yet another 19 y/o raver broughtin by his friends for similar behavior as
the guy on your last shift. BP180/90, P95, T98.7, R20,
O298%RA
He is as pissed off as the other guy,pupils dilated, his face is red, but he isnot sweating like your previous guy
Toxidrome?
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Anticholinergic
Presents similar tosympathomimetic
without thediaphoresis
Turns out thisparticular patient got
Benadryl instead ofMDMA. When thefirst one did not work,he ate 20 more
TMT:supportive, cool,benzodiazepines, consider
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Case #3
25 y/o landscaper brought by his
coworker into the ER obtunded
BP 90/40 P40 R8 T98.7 O275%NRB
He is obtunded, has copious wet
secretions and diarrhea, pupils pinpoint What toxidrome is presented here?
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Cholinergic
DUMBELS-diarrhea, urination,
miosis,bradycardia,emesis, lacrimation,salivation
TMT:*decontaminate pt. iforganophophate
*Atropine
*2-PAM until secretions
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CASE #4
You are working the Saturday night
shift when a 18 y/o female is dropped
out of a speeding BMW
She is taking shallow breaths and is
unconscious BP90/40, P50, R5, T97.8, O2
68%NRB
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CASE #4
Her pupils arepinpoint and herrespiratory effort ifminimal
You notice marks onher arms
Toxidrome? Opioids
TMT:
*Naloxone
*supportive
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An important note
Opioids and sedative
hypnotics can appear
the same Pupils will usually be
spared with sedative-
hypnotics (s-h)
Respirations mostly
preserved with s-h
Examples:GHB,
benzos, ethanol,
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Case #5
This patient is a 35 y/o female with a
history of depression and multiple
psychiatric admissions for OD
Her husband brings her to the ED
saying he thinks she overdosed again BP175/100, P125, T100.7, R22,
O298%
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Case #5
She is agitated and can not stop
moving around
In site of IV fluids, she remains
tachycardic and somewhat psychotic
What drug has she overdosedon/toxidrome?
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SSRI/Serotonin syndrome
Altered MS, agitation, fever, tremors, ataxia
Be careful as serotonin syndrome can mimicthyrotoxicosis (a deadly disease if missed), NMS,MAOIs/tryptophan, and withdrawal symptoms
Usually diagnosed per med history
Can present weeks after stopping SSRI
TMT:
*benzos
*supportive
*cyproheptadine
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Antidotes
Acetaminophen-NAC
Arsenic-BAL
Mercury-BAL
Lead-Dimercaprol, EDTA
Carbon monoxide-O2,
hyperbaric in severe/pregnant
Cyanide-amyl nitrite OR
sodium nitrite, sodium
thiosulfate
Ethylene glycol/methanol-
ethanol, fomepizole
Iron-deferoximine
Nitrites-methylene blue
Organophosphates-atropine,
pralidoxime (2-PAM)
Opioids-naloxone
Phenothiazines-diphenhydramine,
Benzotropine
Isoniazid (INH)-pyridoxine
Digoxin/Oleander-Digitalis Fabfragments
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In Summary
ABCs including early antidotes
GI decontamination early
Get a good overdose history if possible
Look at the patient and try to match
clinical symptoms with a toxidrome Look for skin markings/do you smell
anything unusual?
Get poison center involved
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Questions?