Think Like a Toxicologist
Steven A. Seifert, MD, FACMT, FAACT
Professor, Department of Emergency Medicine
Medical Director, New Mexico Poison Center
sseifert@salud.unm.edu
The Poisoning Problem
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Poisoning is the #1 cause of trauma-related
deaths (estimated 50,000/yr)
> 2.3 m exposures reported to US Poison
Centers in 2013
52% in children < 6
 Reason:
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Intentional 16%; Unintentional 84%
Deaths
1190 (0.05%)
 19% of unintentional deaths therapeutic error
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Poison Center System
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American Association of Poison Control Centers
(AAPCC) (www.aapcc.org)
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Center accreditation
Specialist in poison information (SPI) certification
National Poison Data System
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Data Use
Annual Report (281 pages) publically available: www.aapcc.org
Federal advocacy
55 Regional Poison Centers
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Save lives / Save money / Deliver regional benefits
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Cost avoidance
Indirect (and direct) patient care / consultation
Demographics / Toxicosurveillance
Continuity of Care
Research
Prevention/Education
Karen, PharmD
Rose, PharmD, CSPI
Sara, PharmD, CSPI
Holly, PharmD, CSPI
Stevie, PharmD, CSPI
Susan Smolinske,
PharmD, DABAT,
Managing Director
Jennifer, PharmD, CSPI
Damon, PharmD, CSPI
Steven Seifert, MD
Medical Director
Lee, PharmD, CSPI
Suzi
LaDonna PharmD, CSPI
Gordon, PharmD, CSPI
Drug Info.
Heather
Admin Asst.
Poisoning Morbidity and Mortality
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Morbidity
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Moderate and major effects: 138,000 = 5.7 % of
exposures (NPDS)
Mortality
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~1,500 deaths reported to PCs = 0.05% of exposures
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0.0022% of pediatric exposures
20 deaths in NM (2013)
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NM deaths = 0.1% of exposures (double national average)
Management Site
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74% Managed outside of healthcare facility
22.4% Managed in healthcare facility
3.3% Admitted to ICU
Top 5 Substances in Human Exposures
1.
2.
3.
4.
5.
Analgesics (primarily APAP)
Cosmetics / Personal Care Products
Cleaning Substances
Sedative/Hypnotics/Antipsychotics
Foreign Bodies/Misc
Top 5 Substances in Pediatric Exposures
1.
2.
3.
4.
5.
Cosmetics and Personal Care Products
Analgesics
Cleaning substances
Foreign Bodies / Misc
Topical Preparations
Top 10 Categories in Fatalities
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Sedative/Hypnotics/Antipsychotics
Cardiovascular Drugs
Opioids
Acetaminophen Combinations
Stimulants and Street Drugs
Acetaminophen Alone
Alcohols
Antidepressants
Serotonin Reuptake inhibitors
Antihistamines
Evidence-based Practice

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Grade “A” studies on GI decontamination;
antidote development & use; enhanced
elimination, etc.
Consensus documents
Triage criteria
 Managements

Example: Trends in GID: 1986-04
% 15
5.2
10
5
5.6
Char coal
1.6
0.66
13.3
0.2
0
1986
2004
Lavage
I pecac
Ipecac
Lavage
Charcoal
Anchor Bias/Hidden Tox

Context of discovery may predispose to too
rapid attribution of toxicologic etiology
“Facts” are fluid
 Beware anchor bias
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Keep tox in differential / Occult presentations
CO; APAP
 Drug accumulation (ASA, Dig, Li, Phenytoin)
 Drugs of abuse (myriad presentations/hidden hx)
 Drug-drug/Drug-food interactions
 Adverse drug effects
 Withdrawal
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One More Thing
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Use a drug-drug interaction tool with EVERY
prescription you write
Case
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17 yo f, unresponsive at home in the morning
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Empty pill bottles belonging to her parents
Oxycodone
 Atenolol
 Gabapentin
 Sertraline
 Metformin
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Case
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SocHx:
Stressful home situation / recent departure of father
 No prior history of overdose or self-harm
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Patient’s medications: None
Allergies: None
Think Like A Toxicologist
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What’s the DDx?
What is the “standard” workup of the
unresponsive patient w/ tox in the ddx
What are the expected toxic effects of the
known or suspected substances?
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Pharmacodynamics:
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Does the clinical presentation match?
What additive, antagonistic, and/or synergistic
effects might be anticipated?
Pharmacokinetics:
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What duration of effects anticipated?
Think Like A Toxicologist
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What evaluations would be helpful
Clinical exam
 Labs
 Other diagnostic tests
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What are the tox-specific managements
Decontamination?
 Specific antidotes?
 Enhanced elimination?
 Symptomatic/supportive care?
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Case: What’s the DDx?
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Causes of unresponsiveness?
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Acute medication/substance overdose
Infections
Metabolic disorders
Trauma / ICB / Endocrine / etc.
Standard” workup of the unconscious /
unresponsive patient w/ tox in the ddx
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BMP
ECG
Acetaminophen (APAP); Salicylate
Other tests based on history / exam / context
Case: Physical Exam
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Vitals:
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HR 52, BP 70/48, RR 8,
Sat 84% Temp 37
General: Unresponsive
HEENT:
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Membranes moist
Supple neck
Pupils 1-2mm; react poorly
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Oxycodone
Atenolol
Gabapentin
Sertraline
Metformin
CV: Bradycardia
Lungs: Clear
Abdomen: Benign; no BS
Skin: Warm, dusky, dry
Neuro: Non-focal
Labs / Other Tests
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CBC – Normal
Chem 7
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Na 140
K 4.1
Cl 100
Bicarb 15
Bun 18
Cr 0.9
Glucose 55
Anion Gap ?
Lactate 8
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Urine pregnancy
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Negative
ASA = undetectable
APAP = 230 mg/dL
U Tox
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Oxycodone
Atenolol
Gabapentin
Sertraline
Metformin
positive for opioids
ECG
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Sinus @ 50; QRS 80;
QTc 560
What’s Going On?
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Oxycodone
Atenolol
Gabapentin
Sertraline
Metformin
Medication effects
Oxycodone: CNS; RR; pupils; Opioid Toxidrome
 Atenolol: BP; Heart Rate
 Gabapentin/Sertraline: Additive CNS
 Sertraline: CNS depression; QTc prolongation
 Metformin: Hypoglycemia; Lactic acidosis (MALA)
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What is a Toxidrome?
= Toxic Syndrome
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Collection / Constellation of findings that
suggest a substance or substance class
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Allows you to refine ddx, anticipate effects, choose
specific managements, avoid problems
Where to focus your attention
Vitals
 Pupils
 Overall physical examination
 Think autonomic nervous system!
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Opioid Toxidrome
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Miosis (+/-)
Hypoventilation
(decreased resp. rate!)
Coma
Bradycardia
Hypotension
Anticholinergic Toxidrome
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Tachycardia
HTN
Urinary retention
Decreased bowel sounds
Dry skin
Seizures
Hyperthermia
Cholinergic Toxidrome
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“SLUDGEB…B…B…BAM”
Sialorrhea
Lacrimation
Urination
Diarrhea
Gastric upset
Emesis
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Bradycardia,
Bronchorrhea,
Bronchospasm
Abdominal pain
Miosis
Sympathomimetic Toxidrome
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Diaphoresis
Mydriasis
Tachycardia
Hypertension
Hyperthermia
Seizures
Other Toxidromes
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Non-specific sedative-hypnotics
Metabolic acidosis
Serotonin syndrome
Neuroleptic malignant syndrome
Withdrawal syndromes
Others
Management: Initial Steps
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Pre-hospital
Dextrose
 Oxygen
 Naloxone
 Thiamine
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In-hospital / Supportive Care
ABCs
 Monitor
 IV
 Oxygen
 Perfusion
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Tox-specific Managements
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GI-decontamination?
Applicable < 5% of cases
 Mostly activated charcoal (AC); rarely lavage or
Whole Bowel Irrigation
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Specific Antidotes?
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Indications; proper use; contraindications
Enhanced elimination techniques?
Volume of distribution? Protein binding? Other
properties?
 Urine alkalinization; Multi-dose AC; Hemodialysis;
Cardio-pulmonary bypass (ECMO)
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Common Tox Presentations
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Agitation
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Benzos; Ketamine; Propofol; RSI; Avoid neuroleptics
Rhythm disturbances
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Tachycardia: Usually does not require tx
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Bradycardia: Tx symptomatic
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Positioning; fluid expansion; pressors
Empiric: Dopamine; NE; Neosynephrine; Vasopressin
Specific: Glucagon (b-blockers); Insulin (Ca-channel blockers
Seizures
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Atropine; pacer
Hypotension
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Calcium channel blockers; Avoid b-blockers
Benzos; Pyridoxine; Levetiracetam; Propofol; Avoid
phenytoin
Lipophilic cardiotoxics: Lipid emulsion; ECMO
Case: Management
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Naloxone to reverse opioid effects
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Must be titrated to effect and avoid withdrawal
Atropine / Glucagon for b-blocker
bradycardia/hypotension
Optimization of K, Ca, Mg for QTc, monitoring
and preparedness to manage Torsades de Pointes
Monitoring of acidosis; bicarbonate if needed;
hemodialysis if needed
N-acetylcysteine for elevated acetaminophen level
Nomogram
for Acute Acetaminophen Exposures

Use nomograms and
resources properly
Do not send pre-4h APAP
 Know application of
nomogram
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Information Resources
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MicroMedex (PoisIndex)
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Up-to-Date
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Library Database (“M”)
Library Database (“U”)
Other texts/pubmed/ etc.
Use with expert guidance
2014.8
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National Poison Data System
New Mexico Poison Center Website
National PC Number: 1-800-222-1222
Recent completion of clinical and database studies
Ongoing research
BWS AV
 Database studies
 Participation in ACMT ToxIC database
 Methamphetamine course (Aug 21)
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Your Primary Resource in Poisoning

New Mexico Poison
Center
1-800-222-1222 nationwide
 2-2222 from within
UNMH
 Poison Specialists
24/7/365
 Medical Toxicologist
always available
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