Tox Flashcards
3 types of GI decontamination
Gastric lavage
Activated charcoal
Whole bowel irrigation
How to do gastric lavage
Put NG/OG, +/- intubate
Irrigate with 250 mL saline at a time (10mL/kg in kids) in aliqouts until fluid runs clear and nothing comes out
Indications for gastric lavage
Not many now. Maybe if can’t give charcoal and pt intubated
Dose of Activated charcoal
50-100 g in adults
1g/kg in kids
Indications of AC
Within 2 hrs of ingestion of toxin (reasonable to stretch to 4 if ongoing symptoms/toxicity)
Substance that will bind AC
LOC appropriate
Substances where AC shouldn’t be given
PHAILS
Pesticides
Heavy metals
Alcohols/acids/alkali
Iron
Lithium
Solvents
When to do multitude activated charcoal
When there is eneterohepatic circulation
Eg carbemazepine, phenobarbital
Contraindications to activated charcoal
-Dec LOC/unprotected airway (can tube first)
-more than 2 hours from ingestion (can stretch it, esp if massive or sustained release product)
-PHAILS
Common indications for whole bowel irrigation
Body packers,
Sustained release meds
Metals
How to do WBI , what are the endpoints
Instill PEG solution at a rate of 1L/h until clear rectal effluent or 10L has been used
3 methods for enhanced elimination of a toxin
Mdac
Urinary alkalinization
HD
Toxins where mdac is indicated
Carbamazepine
Phenobarbital
Dapsone
Theophylline
How to do urinary alkalinization
150 meq (3 amps) sodium bicarbonate in 1L D5W infuse at 2X maintenance rate
Toxins that urinary alkalinization works
Aspirin
Methotrexate
Phenobarbital
Aka weak acids
4 drug characteristics for HD to work
4 main drugs that can be removed with HD
Alcohols
Aspirin
Lithium
Metformin (not dialyzable, but helps with severe acidosis)
Pathognomonic ECG finding for sodium channel blockade
Terminal R wave in avr
4 types of toxins that cause bradycardia
beta blockers are the top one
3 toxins classes that cause tachycardia
3 toxins/types of toxins that cause QRS widening
4 main alcohols to know
ethanol, methanol, ethylene glycol, isopropyl alcohol
how and why does fomepizole work?
blocks ADH (alcohol dehydrogenase) preventing toxic metabolites from methanol and ethylene glycol from forming
where is methanol found?
what is the toxic metabolite?
wiper fluid, antifreeze
formix acid is metabolite
anion gap vs osmolar gap in methanol and ethylene glycol ingestion?
osmolar gap is initially elevated, then decrease as anion gap rises in “X” like pattern, this happens as parent compounds (osmoles) get converted to metabolites (anions)