Bielefeld Lena, Auwärter Volker, Pollak Stefan, Thierauf-Emberger Annette
Institute of Forensic Medicine, University Medical Center Freiburg, Albertstraße 9, 79104 Freiburg, Germany.
Institute of Forensic Medicine, University Medical Center Freiburg, Albertstraße 9, 79104 Freiburg, Germany.
Forensic Sci Int. 2015 Feb;247:23-7. doi: 10.1016/j.forsciint.2014.11.008. Epub 2014 Nov 22.
The Widmark's equation (C [BAC]=A/p×r) is the most commonly used formula in legal medicine to estimate the blood alcohol concentration (BAC) from the amount of ingested ethanol and vice versa. Within a drinking experiment with a target BAC of 1.2 g/kg, a 75-year-old participant reached a maximum BAC of 1.83 g/kg and showed signs of severe ethanol intoxication, while the other nine subjects (age: 19-31 years) had BACs close to the target BAC. This incident brought up the question, if the Widmark's equation is an appropriate tool for aged persons.
A drinking experiment with 50 elderly voluntary test persons (22 males, 28 females, mean age and range [males]: 69.7 years, 60-84 years, mean age and range [females]: 68.5 years, 61-78 years) was performed. The amount of ethanol leading to a BAC of 0.6 g/kg was estimated individually using the Widmark's equation (used Widmark factors: 0.7 for males, 0.6 for females). After drinking, the blood ethanol concentrations were measured using headspace gas chromatography/flame ionization detection.
The measured maximum BACs of the elderly participants were significantly higher (α=0.01) than the target BAC (mean maximum BAC and range: 0.627 g/kg, 0.3-0.81 g/kg, for males: 0.616 g/kg, 0.32-0.78 g/kg, for females: 0.635 g/kg, 0.3-0.81). The calculated Widmark factors showed a high coefficient of variation (for males: 0.7±0.138 [0.55-1.2, CV: 19.7%], for females 0.59±0.119 [0.46-1.08, CV: 20.2%]).
The results demonstrate that BAC calculations by Widmark's equation in elderly individuals may be complicated by a high variation of Widmark factors. There is a tendency to an elevation of the actual BAC with increasing age.
维德马克方程（C[BAC]=A/p×r）是法医学中最常用的公式，用于根据摄入乙醇量估算血液酒精浓度（BAC），反之亦然。在一项目标BAC为1.2 g/kg的饮酒实验中，一名75岁的参与者达到了1.83 g/kg的最高BAC，并出现了严重乙醇中毒的症状，而其他九名受试者（年龄：19 - 31岁）的BAC接近目标BAC。这一事件引发了一个问题，即维德马克方程是否是适用于老年人的工具。
对50名老年自愿受试者（22名男性，28名女性，平均年龄及范围[男性]：69.7岁，60 - 84岁；平均年龄及范围[女性]：68.5岁，61 - 78岁）进行了饮酒实验。使用维德马克方程（使用维德马克因子：男性为0.7，女性为0.6）分别估算导致BAC为0.6 g/kg的乙醇量。饮酒后，使用顶空气相色谱/火焰离子化检测法测量血液乙醇浓度。
老年参与者测得的最高BAC显著高于目标BAC（α=0.01）（平均最高BAC及范围：0.627 g/kg，0.3 - 0.81 g/kg，男性为0.616 g/kg，0.32 - 0.78 g/kg，女性为：0.635 g/kg，0.3 - 0.81）。计算得出的维德马克因子显示出较高的变异系数（男性：0.7±0.138[0.55 - 1.2，CV：19.7%]，女性：0.59±0.119[0.46 - 1.08，CV：20.2%]）。
结果表明，在老年人中使用维德马克方程计算BAC可能因维德马克因子的高度变异而变得复杂。随着年龄增长，实际BAC有升高的趋势。
