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Flashcards in Toxic Alcohols Deck (13):

What is the Ddx of an elevated Osmol Gap:

· The alcohols:
o EtOH
o Methanol
o Ethenol
o Isopropanolol
o Propylene glycol (Ativan/diazepam/dilantin/dig/phenobarb/septra IV)
· Sugars + ketones:
o Mannitol
o Acetone (as seen in DKA/AKA/SKA)
· Ethyl ether
· Lipids:
o Hyperlipidemia
· Protein:
o Hyperprotemia à from sepsis, renal failure
· Contrast dyes
· Acidosis


DDx double Gap (ie AG/Osm gap)

· Methanol / ethylene glycol
· End stage renal Dz
· Paraldehyde / formaldehyde
· Acetonitrate
· Lactic acidosis
· Propylene glycol
Critical illness, multiorgan failure


List products found in the home that contain methanol.

- Gasoline industrial Antifreeze
- Windshield washer fluid
- Carburator fluid
- Duplicator fluid
- Hobby (model airplane) engine fuel
- Embalming fluid & formalin
Caterer gas for food heaters
- Gasohol
- Dry gas
- Sterno (silver polish)
- Glass cleaners
- Thinners
- Adhesives, inks


What occupations are at high risk for inhalation of methanol?

- Painting
- Glazing
- Lithography


Describe the metabolism of methanol.

methanol oxidised by ADH to formaldehyde
converted th Aldehyde by aldehyde dehydrogenase (AD) to formic acid
then with folic acid converted to CO2 and water


What are the two main complications of severe methanol toxcity?

- Optic neuropathy – Visual impairment and blindness
Putaminal necrosis – Parkinsonian motor dysfunction


What urinary finding is associated with ethylene glycol toxicity?

- Calcium oxalate crystals


What products contain ethylene glycol?

- Commercial antifreeze
- Commercial coolant
- Airplane deicing solutions
- Hydraulic brake fluid
- Industrial solvents/precursors
- Paints
- Cosmetics


Describe the metabolism of ethylene glycol.

Hepatic metabolism (70%)
- Hepatic oxidation by ADH and other oxidative enzymes to various organic toxic aldehydes and acids.
- Glycoxylic acid can be metabolized to non-toxic metabolites with thiamine and pyridoxine as co-factors
Renal clearance (30%)


Describe the timing and clinical characteristics of each stage of ethylene glycol toxicity.

Stage I (30 min to 12hr): inebriation

Stage II (12-24hr): cardiopulmonary stage

Stage III (24-72hr) renal stage

stage IV (6-12d): delayed neuro sequelae


What are the indications for ADH blockade in toxic alcohol ingestion

1. Hx with OG GT 10
2. Plasma concentration GT 3.2mmol/l EG or 6.2mmol/L methanol
3. suspected ingestion with:
-pH LT 3
-HCO3 LT 20
-OG GT 10
oxalate crystalutia


List indications for hemodialysis in methanol or ethylene glycol toxicity?

pH LT 7.1
pH drom 0.5+ despite HCO3 infusion
pH LT 7.3 despite HCO3 infusion
renal failure
deteriorating vitals despite care
visual or neuro impairement
methanol level GT 15.6


List additional therapies that are indicated in methanol/EG toxicity?

- Methanol:
o Folic acid or Leucoviron (Folinic acid) 50mg iv q4h
- Ethylene glycol:
o Thiamine 100mg x 1
o Pridoxine 60mg x 1
Consider MgSO4 as well