Intoxication by the following agents (or accumulation, in the case of acetone in diabetic or alcoholic ketoacidosis) produces an elevated osmolar gap: methanol, ethanol, ethylene glycol, acetone, and isopropanol.

Although several drugs can potentially contribute to the osmolar gap (e.g., salicylates, paraldehyde, and chloral hydrate), they are rarely present at concentrations sufficient to raise osmolarity.

A neuro-ophthalmologic examination of the patient might reveal several findings. Results of examination of visual fields, as determined by perimetry, typically indicate central scotomata early in the course of methanol poisoning (soon after onset of acidosis), with peripheral constriction of visual fields a late finding. Dilated, unreactive pupils and dim vision are characteristic. The result can be bilateral blindness, which is usually permanent.

See the answer to Pretest question (d) above.

One-hundred proof vodka is actually 50% ethanol by volume. A loading dose equivalent to the required 7.5 mL/kg of 10% ethanol can be achieved with vodka as follows: In a 70 kg person, a total of 525 mL of 10% ethanol would be needed (7.5 mL/kg×70 kg=525 mL).

525 mL×10%=X mL×50%

52.5 mL=0.5X mL

X=105 mL of the 50% ethanol

In summary, 105 mL of 50% ethanol with 5% dextrose in water added to total 525 mL will produce a 10% ethanol solution. (See Treatment and Management, page 11.) This quantity of vodka or an equivalent amount of ethanol from another distilled spirit can be initially administered orally or by gavage.