Parameters:
(1) estimate of the initial blood ethanol concentration in mg/mL assuming immediate absorption of all the ethanol ingested
(2) body weight in kilograms
(3) distribution factor for ethanol (Widmark factor)
(4) ethanol concentration in the urine in mg/mL
volume of pure ethanol ingested in mL = Widmark equation =
= (distribution factor) * (estimated initial blood concentration in mg/mL) * (body weight in kilograms)
where:
• 1 mg/mL ethanol = 0.1 g/dL
• For the Japanese the average distribution factor is 0.71
• If a person drinks a large volume of absolute ethanol in a short period, the intracardiac ethanol concentration should approximate the peak ethanol concentration. If the person survives any length of time after the ingestion then it is necessary to extrapolate back to t = 0.
• A person may have ingested more than the amount calculated if it is still in the stomach or GI tract or if it were vomited out.
• As noted previously, values > 0.45 g/dL (4.5 mg/mL) are often lethal.
volume of alcoholic drink ingested in mL =
= (volume of pure ethanol ingested in mL) * (200 / (proof))
ratio of ethanol concentration in blood to urine =
= (ethanol concentration in blood) / (ethanol concentration in urine)
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Ratio
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Time at Death
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> 1
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absorption phase
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1
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60 - 100 minutes after ingestion
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< 1
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after peak phase
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