Temperature-based death time estimation with only partially known environmental conditions
Temperature-based death time estimation with only partially known environmental conditions
复制标题
仅部分已知环境条件下基于温度的死亡时间估计
DOI：
--
复制
发表时间：
2005
期刊：
影响因子：
--
通讯作者：
M. Hubig
中科院分区：
文献类型：
--
作者：
G. Mall;M. Eckl;I. Sinicina;O. Peschel;M. Hubig
温度导向的死亡时间的确定是基于死后直肠冷却的数学模型曲线。所有的数学模型都需要了解环境条件。在法医学实践中，有时不是在死亡现场立即怀疑是他杀，而是在事后对尸体进行外部检查时才怀疑。死亡现场的环境温度仍然未知，或者只能粗略地重建。在这种情况下，出现的问题是，是否有可能仅从较长时间内记录的直肠温度数据来估计死亡时间。本研究从理论上推导出与初始温度和环境温度无关的公式，从而证明直肠温度数据中包含了估计死亡时间所需的信息。由于死亡现场的环境温度可能与温度记录期间的环境温度不同，因此必须使用额外的因素。这就是身体核心在热上与环境很好地隔离，并且在环境温度突然变化后直肠温度的下降将以与突然变化之前相似的速度持续一段时间。本研究进一步提供了这种情况下的曲线拟合程序。采用最常用的Henssge模型对35具尸体的直肠冷却数据进行了测试。在所有案例中死亡时间都是准确的。进入法医学研究所后，将尸体在恒定环境温度下保存12-36小时，并连续记录直肠温度。尽管在进入研究所之前的环境条件未知，但在所有实验中，曲线拟合程序都可以有效地估计死亡时间。对估计偏差进行统计分析。95%置信区间为±4 h，与已知环境温度下Henssge模型的95%置信区间相比，这似乎是合理的。所提出的方法可用于确定死亡时间，即使在死亡现场的环境温度和直肠温度无意中未被记录的情况下。
The temperature-oriented death time determination is based on mathematical model curves of postmortem rectal cooling. All mathematical models require knowledge of the environmental conditions. In medico-legal practice homicide is sometimes not immediately suspected at the death scene but afterwards during external examination of the body. The environmental temperature at the death scene remains unknown or can only be roughly reconstructed. In such cases the question arises whether it is possible to estimate the time since death from rectal temperature data alone recorded over a longer time span. The present study theoretically deduces formulae which are independent of the initial and environmental temperatures and thus proves that the information needed for death time estimation is contained in the rectal temperature data. Since the environmental temperature at the death scene may differ from that during the temperature recording, an additional factor has to be used. This is that the body core is thermally well isolated from the environment and that the rectal temperature decrease after a sudden change of environmental temperature will continue for some time at a rate similar to that before the sudden change. The present study further provides a curve-fitting procedure for such scenarios. The procedure was tested in rectal cooling data of from 35 corpses using the most commonly applied model of Henssge. In all cases the time of death was exactly known. After admission to the medico-legal institute the bodies were kept at a constant environmental temperature for 12–36 h and the rectal temperatures were recorded continuously. The curve-fitting procedure led to valid estimates of the time since death in all experiments despite the unknown environmental conditions before admission to the institute. The estimation bias was investigated statistically. The 95% confidence intervals amounted to ±4 h, which seems reasonable compared to the 95% confidence intervals of the Henssge model with known environmental temperature. The presented method may be of use for determining the time since death even in cases in which the environmental temperature and rectal temperature at the death scene have unintentionally not been recorded.