Tox: Methanol

-solvent in paint, windshield wiper fluids, antifreeze
-methanol > liver > alc dehyrogenase > formaldehyde and formic acid (+folate) > CO2
-C-OH > C=OH and COOH
-lg osmolal gap
-formaldehyde > retina > edema and optic papillitis
-formic acid > high anion gap met acidosis (Mudpiles)
-methanol is a gi irritant, can cause pancreatitis
si/sx
-no sx x 12-18hr after ingestion
-cns dep, visual disturb (*looking at a snowstorm), n/v/abd pain
-retinal edema, hyperemia of optic disk, abd tenderness
lab
-high anion gap met acid, high osm gap, methanol level
Rx
-IV fluids
-FSBS
-Thiamine
-nalaxone if ams
-charcoal - won't bind alcohols, but give if coingest
-folate 50 mg iv q 4 hr
-fomepazole 15 mg/kg IV load followed by 20 mg/kg q 12 hr x 4 doses; binds 8000x > ethanol for alc dehydrog, fewer SEs; begin if suspect meth poisoning; anion gap met acid and an osm gap; meth level >20; or pt requires dialysis
-ethanol 0.6 g/kg IV load folloed by 0.11 g/kg/h cont infusion, or 0.15 g/kg/h in heavy drinker, adjust infusion to keep etoh level 100 to 150; cont etoh treatment until methanol level is 0 and acidosis is resolved
-oral etoh bev - gram of etoh = cc beverage x .9 x (proof/200)
-dialysis indications - sig toxicity; meth level >20; presence anion-gap met acidosis
-Labs: BUN, Cr, glc, lytes
Dispo:
-any hx of ingestion admitted regardless of symptoms b/c may take 12-18 hrs to develop sx