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Flashcards in Toxicology Deck (20):
1

Charcoal, optimal ratio of  charcoal: toxin
poorly bound (4)

 

10:1
small molecules (lithium, iron, cyanide), hydrocarbons, alcohol, acid/alkalai

2

Antidotes

BAL, DMS (3)

FFP / Vit K / PCCs

Calcium, glucagon, gluc/insulin, intralipids

Sodium nitrite, sodium thiosulfate, hydroxycobalamine

Arsenic, mercury, lead (add EDTA)
warfarin
calcium channel blocker

cyanide

3

Antidote 2

Alkaline diuresis, hemodialysis (2)

Bicarbonate, ethanol, dialysis, 4-MP (2)

Glucagon, intralipids

Protamine

Aspirin, barbiturates
ethylene glycol, methanol
beta blocker
heparin

4

Antidote 3

pyridoxine (a.k.a.)
sodium bicarbonate, intra-lipids
methylene blue (2)
calcium, magnesium

INH; vitamin B6
TCA
nitrates, met hemoglobin EMEA
hydrofluoric acid

5

Dereroxamine

atropine, 2-PAM

octreotide and two other things

Iron
organophosphate (cholinergic and central nicotinic)
Oral hypoglycemic along with glucagon and glucose

6

Anion gap formula

MUDPILES pneumonic

(Na) - (Cl + CO2), normal < 12

MUDPILES pneumonic - causes of anion gap metabolic acidosis

M    Methanol, metformin, massive ingestions

U    Uremia

D    DKA

P    Paraldehyde

I    Iron, INH

L    Lactic acidosis (CO, CN)

E    Ethylene glycol

S    Salicylates

7

Increased osmolar gap (3)

false positives
amphetamines
TCAs
PCP

Alcohol toxic (acetone, isopropanol, methanol, ethylene glycol) or not, mannitol, ketoacidosis

 Osmolar gap = Actual - Calculated (nl 285-295) = 2 Na + BUN/18 + Glu/18 + EtOH/4.6

amphetamines: Sudafed
TCAs: cyclobenzaprine, carbamazepine, diphenhydramine, phenothiazines
PCP: ketamine, dextromethorphan

             

8

Drug levels helpful when predictive of subsequent toxicity or guides specific therapy (5)

Iron, lithium, acetaminophen, aspirin, digoxin

9

Anticholinergic toxidrome

classic examples (5)

key difference with similar toxidrome:

“Hot as hell, blind as a bat, dry as a bone, red as a beet, mad as a hatter”; Dry, flushed skin, dry mucus membranes, mydriasis, decreased bowel sounds, urinary retention

examples: atropine, antihistamine, Jimsonweed, Parkinson's medications (L dopa), , phenothiazines, TCAs

key difference: sympathomimetic has diaphoresis rather than dry skin

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10

Anticholinergic treatments of

Classic toxidrome (Mad as hatter.....) normal and if severe

wide complex tachycardia
torsade de pointes

Benzodiazepines, Physostigmine if very severe and no TCA
bicarbonate
magnesium, overdrive pacing
 

11

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12

Sympathomimetic treatment

Mimic of opiod OD

Benzodiazepine

Clonidine

13

Cholinergic toxidrome

Key examples (2) and mechanism

muscarinic effects mnemonic

 

Organophosphate insecticides, chemical warfare agents, some mushrooms
inhibit cholinesterases -> increases acetylcholine

SLUDGEM- Bs

salivation, lacrimation, urination, diarrhea, GI distress, emesis, miosis

Bs: –Bradycardia, Bronchospasm, Bronchorrhea 

14

Cholinergic toxidrome

Nicotinic effects (3)

tx

Muscle weakness, fasciculations, respiratory failure

atropine, 2-PAM (Pralidoxime)

15

Withdrawal syndromes
common treatment for alcohol, barbiturates, benzodiazepines, cocaine, clonidine

Benzodiazepines, clonidine

16

Tylenol tox

mechanism

stages

Saturated normal metabolism shifts to minor pathway cytochrome P450 ->  when glutathione depletes, toxic free radical metabolits NAPQI accumulates and damages hepatocytes

 

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17

Tylenol tox

toxic ingestion mg/kg; grams average adult

4 hour toxic level

Mech

Use > 24 hours presentation?

140 mg per kilo, 7 to 10 g
140 at four hours
provides necessary cofactor to metabolize NAPQI

>24 hours: yes

18

Wernicke’s encephalopathy sx (4)

Korsakoff’s psychosis sx (2) 

Wernicke’s encephalopathy: Oculomotor crisis

CN VI palsy (lateral rectus), nystagmus, ataxia, global confusion

Korsakoff’s psychosis: Retrograde amnesia, confabulation

19

Methanol
metabolic presentation

Pathogenesis
Key symptom

Other sx (3)

Anion gap metabolic acidosis with increased osmolar gap

alcohol dehydrogenase creates formaldehyde and formic acid

Visual changes/blindness

Seizures, resp failure, pancreatitis

 

20

Methanol

Antidote (2)

Adjuncts if refractory to above (2)

Fomepizole (4MP) -> prevents conversion leading to renal excretion

Ethanol (preferentially metabolized)

Dialysis, bicarbonate