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Establishing the limitation of death

Determination of the age of death . The determination of the age of death is an expert determination of the time of its occurrence in hours for the early postmortem period (up to 2-3 days) or in days (and even in months) - in the presence of late changes of the corpse.

When investigating crimes against a person’s life, there is often a need for a forensic medical determination of the statute of limitations for the occurrence of death, which provides great assistance to the bodies of inquiry, investigation and court and is often crucial for identifying a specific person who committed a crime.

The study of the problem of the limitation of death, undertaken to address specific forensic issues, is also of considerable importance for health authorities. Prescription of death, determined in the early stages of the post-mortem period, is determined primarily on the basis of changes related to the survival of tissues and organs. The results of studies of early post-mortem changes obtained by forensic physicians with the help of modern laboratory methods can be useful for transplantologists, resuscitators, pathophysiologists, biochemists and representatives of other medical specialties. It is noted that in most tissues, the effects of autolysis are noticeable by 12–18 hours of the post-mortem period and are pronounced by 36–48 hours. The glycogen in the liver is almost undetectable by 24 hours, by the same time the content of DNA and RNA is sharply reduced. A certain dynamics of changes in the activity of enzymes was observed depending on the time from the onset of death, with a pronounced tendency to decrease by 48 h. ATP activity in muscle tissue disappears by 12 h of the post-mortem period.

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Sustainable indicators for early periods of death were obtained using a number of physicochemical and biophysical methods. These primarily include the method of recording changes in the super-weak luminescence (chemiluminescence) of homogenates of various tissues and the determination of the concentration of potassium ions in the blood.

Data were obtained indicating certain patterns in the increase in the body fluids of the content of individual elements ( potassium , phosphorus ) and, conversely, some reduction (sodium) depending on the age of death.

When examining corpses at the place of detection and in studying them in morgue conditions, methods for determining the duration of death based on the dynamics of the formation and development of early and late changes of the corpse are widely used.

Cadaveric spots in the hypostasis stage appear 2–4 hours after death, in the period from 2–4 to 12–14 hours, cadaveric spots disappear when pressed on them and after some time restore their original color. In the diffusion stage, which roughly lasts from 14 to 24 hours, the cadaveric spots turn pale with pressure and restore their color much more slowly, and finally, after 24 hours, the cadaveric spots do not change their color. This pattern of changes in the character of cadaver spots and allows you to tentatively determine the duration of death. However, this technique is pronounced subjective.

Orientation data to determine the limitation of the occurrence of death depending on the recovery time of the color of the delicate spots are presented in Table 1.

Table 1. Recovery time staining of delicate spots, depending on their stages and the duration of death
Stage Time to restore the color of dead spots Time after death h
Hypostasis


Diffusion



Imbibition
5-10 s
30 s
1-2 minutes
5-8 min
8-10 min
15 minutes
15 minutes
Do not fade or turn pale
2
4
6-8
10—12
14—16
18-20
22-24
24—48

The table shows the averages. The color of the cadaveric spots and the time required to restore their color, depend on the cause of death. For example, when dying from mechanical asphyxia, which is characterized by abundant bluish-purple cadaveric spots, the time required to restore their original color is less than death, due to large blood loss, when the color of cadaverous spots recovers more slowly. Thus, in some cases, a certain correction is necessary in the assessment of changes in the delicate spots, taking into account their severity and cause of death.