Toxicology Flashcards
What is the impact of epidemiology of poisoning on clinical decisions?
It informs the approach to treatment and management of poisoned patients.
What should be obtained from a poisoned patient to aid in treatment?
A thorough history, understanding its limitations.
Define ‘toxidrome’.
A group of signs and symptoms and/or characteristic effects associated with exposure to a particular substance or class of substances.
What are the signs of Opioid Toxidrome?
- Tiny pupils
- Respiratory and CNS depression
- Hypoactive bowel sounds
What is the recommended treatment for Opioid Toxidrome?
Naloxone (NARCAN™️)
List the symptoms of Anticholinergic Toxidrome.
- Psychosis
- Dry mucous membranes, urinary retention
- Elevated temperature
- Flushed skin
- Mydriasis
What is the treatment for Anticholinergic Toxidrome?
Physostigmine (use with caution)
What is the Cholinergic (Muscarinic) Toxidrome?
A toxidrome characterized by symptoms such as diarrhea, urination, miosis, bronchorrhea, emesis, lacrimation, and salivation.
What is the treatment for Cholinergic Toxidrome?
Atropine and Pralidoxime
What age group accounts for half of all poisonings?
Children age 1-5
Differentiate between poisoning, intoxication, and overdose.
- Poisoning: Exposure to harmful agents
- Intoxication: Ill-defined term often confused with inebriation
- Overdose: Exposure to pharmacologic substances in suprapharmacologic doses
What routes of exposure may allow for gastrointestinal decontamination?
- Oral
- Transcutaneous
- Inhaled
- Intravenous
- Transmucosal
What are five methods of gastrointestinal decontamination?
- Induced emesis (Syrup of Ipecac)
- Gastric lavage
- Activated charcoal
- Whole bowel irrigation
- Cathartics
What should be considered when deciding on gastrointestinal decontamination?
- Polypharmacy overdoses
- Overdose of substances without specific antidote
- Known or suspected lethal ingestions
What is the survival rate for poisoning cases?
99.8%
True or False: Gastric lavage should be used for all poisonings.
False
What are the risks associated with gastric lavage?
- Aspiration
- Esophageal or gastric perforation
- Decreased oxygenation
- Pneumomediastinum/mediastinitis
What is activated charcoal considered?
The best approximation of a ‘universal antidote’
What are the contraindications for activated charcoal?
- Absent gut motility or perforation
- Caustic ingestions
- Xenobiotics that do not adsorb to charcoal
What are the complications associated with activated charcoal?
- Fatal aspiration
- Small bowel obstruction
- Interference with oral antidotes
What factors indicate ongoing absorption of toxins?
- Recognized high-risk ingestions such as cyanide, colchicine, chloroquine, aspirin, cyclic antidepressants, verapamil, paraquat
Fill in the blank: The removal or binding of a toxin in the GI tract is called _______.
Gastrointestinal decontamination
What are some rare complications of activated charcoal?
- Fatal aspiration
- Small bowel obstruction
- Pneumonitis
- Interference with oral antidotes
- Interference with oral maintenance medications
Complications may arise from activated charcoal administration, particularly in cases of overdose or improper use.
What is a small bowel charcoal bezoar?
A bezoar causing small bowel obstruction after repeated activated charcoal administration
This condition can occur when activated charcoal accumulates in the gastrointestinal tract.
What does MDAC stand for?
Multiple Dose Activated Charcoal
MDAC is a method used to enhance the elimination of certain toxins from the body.
What is the mechanism behind MDAC?
Substances that have already entered the systemic circulation may be pulled back into the gut by activated charcoal if they undergo enterohepatic or enteroenteric circulation, are present in significant amounts in circulating blood, and can be absorbed by charcoal
This process allows for the re-absorption of toxins that might otherwise remain in the bloodstream.
What drug’s toxicity has proven efficacy with MDAC?
Theophylline
Theophylline is known for its narrow therapeutic window and can cause significant toxicity.
What are common symptoms of Theophylline toxicity?
- Agitation
- Delirium
- Tachycardia
- Hypertension
- Tremulousness
These symptoms represent the toxidrome associated with Theophylline overdose.
What is Whole Bowel Irrigation (WBI)?
Mechanical cleansing of the entire GI tract by the instillation of large volumes of fluid
WBI is used to eliminate toxins that charcoal cannot effectively absorb.
What is the preferred solution for WBI and why?
Polyethylene Glycol (PEG or Golytely™) because it does not cause electrolyte disturbances
This makes PEG safer for patients undergoing bowel irrigation.
What are indications for Whole Bowel Irrigation?
- Potentially toxic ingestion of a substance not well absorbed by charcoal
- Substances with prolonged absorption phase
- Rising drug levels despite gastric emptying
WBI is particularly useful in cases where traditional methods of decontamination have failed.