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==Background==
==Background==
===Autonomic Nervous System===
===Epidemiology===
# Parasympathetic - ACh is transm
*In 2014, ~2.2million human exposures reported to US poison control centers
## Muscarinic
*Top 5 substance classes:
###receptors in heart, eye, lung, GI, skin and sweat glands
**analgesics (11%)
### Bradycardia
**cosmetics/personal care products (8%)
### Miosis
**household cleaning substances (8%)
### Bronchorrhea / Bronchospasm
**sedatives/hypnotics/antipsychotics (6%)
### Hyperperistalsis (SLUDGE)
**antidepressants (4%)
### Sweating
*1,835 human exposures resulted in death
### Vasodilation
## Nicotinic
### receptors in both sympathetic and parasympathetic nervous systems
### fasciculations, flaccid paralysis
###?Mild bradycardia, hypotension
# Sympathetic
##ALPHA EFFECTS - vessels, eye, skin
### Mydriasis, HTN, Sweating
##BETA EFFECTS - heart, lungs
### Tachycardia, Bronchodilation


==Diagnosis==
{{Autonomic nervous system receptors}}
===Toxicological Exam===
# All VS (Temp, RR,HR, BP)
# Neuro Exam
##Level of consciousness
##Pupillary exam
##Motor response
#Skin Exam - moisture, temp
# Lung Exam
# Bowel Sounds


===Toxidrome Chart===
==Clinical Features==
{{Template:Toxidrome Chart}}
{{Template:Toxidrome Chart}}
^Consider Sympatholytic when looking at Sedative OD or someone who doesn't respond to Narcan


==DDx for Specific Signs==
==Differential Diagnosis for Specific Signs==
===Hyperthermia===
===Hyperthermia===
#Altered Metabolism
*Altered Metabolism
## [[Aspirin (Salicylate) Toxicity]]
**[[Aspirin (Salicylate) Toxicity]]
## withdrawal states
**withdrawal states
## thyroid hormones
**thyroid hormones
## dinitrophenols
**dinitrophenols
# Increased Muscle Activity
*Increased Muscle Activity
## withdrawal, sympathomimetics
**withdrawal, sympathomimetics
## [[MAOI Toxicity]]
**[[MAOI Toxicity]]
##[[PCP]], LSD
**[[PCP]], LSD
## [[Lithium]]
**[[Lithium]]
## Amoxapine
**Amoxapine
##[[Serotonin Syndrome]]
**[[Serotonin Syndrome]]
# Impaired Heat Dissipation
*Impaired Heat Dissipation
## anticholinergics
**anticholinergics
## antihistamines
**antihistamines
## antipsychotics ([[TCAs]])
**antipsychotics ([[TCAs]])
# [[Malignant Hyperthermia]]
*[[Malignant Hyperthermia]]
## anesthestics
**anesthestics
# [[Neuroleptic Malignant Syndrome]]
*[[Neuroleptic Malignant Syndrome]]
## phenothiazines, [[Lithium]], LevoDopa
**phenothiazines, [[Lithium]], LevoDopa


===Hypothermia===
===Hypothermia===
# Exposure
*Exposure
## [[Ethanol Toxicity]]
**[[Ethanol Toxicity]]
## Sedative hypnotics
**Sedative hypnotics
## Narcotics
**[[Opioids]]
## [[TCAs]]
**[[TCAs]]
## Phenothiazines
**Phenothiazines
## [[Insulin]] ([[Hypoglycemia]])
**[[Insulin]] ([[Hypoglycemia]])


===Increased Respiratory Rate===
===Increased Respiratory Rate===
# Direct Stimulation
*Direct Stimulation
## [[Aspirin (Salicylate) Toxicity]]
**[[Aspirin (Salicylate) Toxicity]]
## [[Metabolic Acidosis]]
**[[Metabolic Acidosis]]
## dintirophenol, pentachlorophenol
**dintirophenol, pentachlorophenol
## hepatorenal failure
**hepatorenal failure
## CNS stimulants (cocaine, amphet, theophylline)
**CNS stimulants (cocaine, amphet, theophylline)
#Tissue [[Hypoxia]]
*Tissue [[Hypoxia]]
##[[CO]]
**[[CO]]
##[[Cyanide]]
**[[Cyanide]]
##[[Hydrogen Sulfide]]
**[[Hydrogen Sulfide]]
##[[Methemoglobinemia]]
**[[Methemoglobinemia]]


===Respiratory Depression===
===Respiratory Depression===
# Central Depression
*Central Depression
## antipsychotics
**antipsychotics
## Chlorinated hydrocarbons
**Chlorinated hydrocarbons
## [[Sedative/Hypnotics]] ([[Ethanol Toxicity]], glycols)
**[[Sedative/Hypnotics]] ([[Ethanol Toxicity]], glycols)
## [[Tricyclic (TCA) Toxicity]]
**[[Tricyclic (TCA) Toxicity]]
## Lomitil
**Lomitil
# Muscle Failure
*Muscle Failure
## [[Organophosphates]]
**[[Organophosphates]]
##[[Marine Toxins]]
**[[Marine Toxins]]
## nicotine
**[[Nicotine Poisoning|Nicotine]]
## strychnine
**strychnine
## botulinis
**botulinis
## Mojave rattlesnake, Cobra
**Mojave rattlesnake, Cobra
 
===Bradycardia===
PACED
*Propranolol/ beta-blockers, poppies (opiates), propoxyphene,
physostigmine
*Anticholinesterases, antiarrhythmics
*Clonidine, calcium channel blockers
*Ethanol or other alcohols
*Digoxin, digitalis
 
===Seizures===
OTIS CAMPBELL
*[[Organophosphates]], oral hypoglycemics
*[[TCA]], [[theophylline]], tramadol
*Isoniazid, Insulin
*[[Sympathomimetics]], [[salicylates]], strychnine
*Camphor, [[carbon monoxide]], [[cyanide]], chlorinated hydrocarbons, [[cocaine]]
*[[Anticholinergics]] (antihistamines), amphetamines, antidepressants (citalopram, TCAs, buproprion)
*[[Methanol]], Methylxanthines (theophylline, caffeine), [[MAOI]]
*[[PCP]], propranolol
*Benzo withdrawal, buproprion, botanicals (hemlock, nicotine), GHB
*EtOH withdrawal, ethylene glycol
*[[Lead]], [[lithium]]
*Lidocaine, lindane (pesticide, scabies)
 
==Evaluation==
===Toxicological Exam===
*All vital signs (Temp, RR, HR, BP)
*[[Neurologic exam]]
**Level of consciousness
**Pupillary exam
**Motor response
**DTRs
*Skin Exam - moisture, temp
*Lung Exam
*Bowel Sounds
*[[ECG]] (ie. look for [[QT prolongation]], QRS prolongation, etc)
 
==Management==
*Depends on agent
*See [[antidotes]]
*"Coma cocktail" when suspecting toxic ingestion (mnemonic = "DONT")
*#[[Dextrose]] (50mg IV)
*#[[Oxygen]]
*#[[Naloxone]] (0.2-0.4mg IV/IM, repeat dose 1-2mg)
*#*Empiric opioid ingestion treatment
*#[[Thiamine]] (50-100mg)
*#*Treat or avoid [[Wernicke encephalopathy]]
*#*Though some suggest giving thiamine prior to dextrose, do NOT let this delay treatment of hypoglycemia!
*#*Case reports of dextrose precipitating Wernicke's involved thiamine-deficient patients receiving prolonged course of IV glucose, NOT with single bolus<ref>Donnino MW, Vega J, Miller J, Walsh M. Myths and misconceptions of Wernicke's encephalopathy: what every emergency physician should know. Ann Emerg Med. 2007;50(6):715-21.</ref><ref>Gussow, L. Myths of Toxicology: Thiamine Before Dextrose. Emergency medicine news. 2007;29(4):3-11.</ref>
 
==Disposition==
*Depends on agent


==See Also==
==See Also==
[[Altered Mental Status (AMS)]]
*[[Altered mental status]]
[[Nicotine Poisoning]]
*[[Traditional chinese medicine toxicology]]
*[[Drug_levels|Drug Levels]]
*[[Antidote]]
*[[Camphor toxicity]]


==Source==
==References==
Originally adapted from BIRNBAUMER
<references/>


[[Category:Tox]]
[[Category:Toxicology]]
[[Category:EMS]]
[[Category:EMS]]

Revision as of 03:27, 26 March 2019

Background

Epidemiology

  • In 2014, ~2.2million human exposures reported to US poison control centers
  • Top 5 substance classes:
    • analgesics (11%)
    • cosmetics/personal care products (8%)
    • household cleaning substances (8%)
    • sedatives/hypnotics/antipsychotics (6%)
    • antidepressants (4%)
  • 1,835 human exposures resulted in death

Autonomic Nervous System Receptors and Their Effects

  • Parasympathetic - ACh is transm
    • Muscarinic
      • receptors in heart, eye, lung, GI, skin and sweat glands
      • Bradycardia
      • Miosis
      • Bronchorrhea / Bronchospasm
      • Hyperperistalsis (SLUDGE)
      • Sweating
      • Vasodilation
    • Nicotinic
  • Sympathetic
    • Alpha effects (vessels, eye, skin)
    • Beta effects (heart, lungs)

Clinical Features

Toxidrome Chart

Finding Cholinergic Anticholinergic Sympathomimetic Sympatholytic^ Sedative/Hypnotic
Example Organophosphates TCAs Cocaine Clonidine ETOH
Temp Nl Nl / ↑ Nl / ↑ Nl / ↓ Nl / ↓
RR Variable Nl / ↓ Variable Nl / ↓ Nl / ↓
HR Variable ↑ (sig) Nl / ↓ Nl / ↓
BP Nl / ↓ Nl / ↓
LOC Nl / Lethargic Nl, agitated, psychotic, comatose Nl, agitated, psychotic Nl, Lethargic, or Comatose Nl, Lethargic, or Comatose
Pupils Variable Mydriatic Mydriatic Nl / Miotic
Motor Fasciculations, Flacid Paralysis  Nl Nl / Agitated Nl
Skin Sweating (sig) Hot, dry Sweating Dry
Lungs Bronchospasm / rhinorrhea Nl Nl Nl
Bowel Sounds Hyperactive (SLUDGE) ↓ / Absent Nl / ↓ Nl / ↓
^Consider Sympatholytic when looking at Sedative OD or someone who doesn't respond to Narcan
Withdrawal from substances have the opposite effect

Differential Diagnosis for Specific Signs

Hyperthermia

Hypothermia

Increased Respiratory Rate

Respiratory Depression

Bradycardia

PACED

  • Propranolol/ beta-blockers, poppies (opiates), propoxyphene,

physostigmine

  • Anticholinesterases, antiarrhythmics
  • Clonidine, calcium channel blockers
  • Ethanol or other alcohols
  • Digoxin, digitalis

Seizures

OTIS CAMPBELL

Evaluation

Toxicological Exam

  • All vital signs (Temp, RR, HR, BP)
  • Neurologic exam
    • Level of consciousness
    • Pupillary exam
    • Motor response
    • DTRs
  • Skin Exam - moisture, temp
  • Lung Exam
  • Bowel Sounds
  • ECG (ie. look for QT prolongation, QRS prolongation, etc)

Management

  • Depends on agent
  • See antidotes
  • "Coma cocktail" when suspecting toxic ingestion (mnemonic = "DONT")
    1. Dextrose (50mg IV)
    2. Oxygen
    3. Naloxone (0.2-0.4mg IV/IM, repeat dose 1-2mg)
      • Empiric opioid ingestion treatment
    4. Thiamine (50-100mg)
      • Treat or avoid Wernicke encephalopathy
      • Though some suggest giving thiamine prior to dextrose, do NOT let this delay treatment of hypoglycemia!
      • Case reports of dextrose precipitating Wernicke's involved thiamine-deficient patients receiving prolonged course of IV glucose, NOT with single bolus[1][2]

Disposition

  • Depends on agent

See Also

References

  1. Donnino MW, Vega J, Miller J, Walsh M. Myths and misconceptions of Wernicke's encephalopathy: what every emergency physician should know. Ann Emerg Med. 2007;50(6):715-21.
  2. Gussow, L. Myths of Toxicology: Thiamine Before Dextrose. Emergency medicine news. 2007;29(4):3-11.