Early cadaveric changes include: Timing of death, determined by the nature of changes in cadaveric spots
Cadaveric spots
Cadaveric spots.
Corpse spots(hypostatici, livores cadaverici, vibices) are perhaps the most famous sign of the onset of biological death. They belong to early cadaveric phenomena, and are, as a rule, areas of skin of a bluish-violet color. Cadaveric spots arise due to the fact that after the cessation of cardiac activity and loss of tone of the vascular wall, passive movement of blood occurs through the vessels under the influence of gravity and its concentration in the underlying areas of the body.
Time of occurrence
The first cadaveric spots appear after 1-2 hours in case of acute death, in agonal death - 3-4 hours after the onset of biological death, in the form of pale areas of skin coloring. Corpse spots reach their maximum color intensity by the end of the first half of the day. During the first 10-12 hours, there is a slow redistribution of blood in the corpse under the influence of gravity. Cadaveric spots can be mistaken for bruises, and vice versa. An incision protects against such an error: in case of bruising, coagulated blood appears, but if staining occurs only from hypostasis, then, depending on the time elapsed after death, they find either only simple hyperemia, or saturation of the corresponding tissues with blood serum.
Characteristic color
Since cadaveric spots are blood visible through soft tissues and skin, the color of cadaveric spots depends on the cause of death.
- In asphyxial death, cadaveric spots have an intense bluish-violet color, like all the blood of a corpse, supersaturated with carbon dioxide.
- In carbon monoxide poisoning, carboxyhemoglobin is formed, which gives the blood a bright red color, and cadaveric spots acquire a distinct reddish-pink tint. They acquire the same color for a while if a corpse is transferred from a warm room to a cold one or vice versa.
- In case of cyanide poisoning, cadaveric spots have a cherry color.
- In cases of death from hypothermia and drowning in water, cadaveric spots with a pinkish-red tint.
- In cases of poisoning with methemoglobin-forming poisons (nitrates, nitrites, Berthollet salt, methylene blue and others) and at certain stages of decay, cadaveric spots have a gray-brownish tint.
- In case of death from massive blood loss, 60-70% of blood is lost during life, cadaveric spots are weakly expressed, never cover the entire lower surface of the corpse, have the appearance of islands delimited from each other, are pale, and appear at a later date.
Stages of development
In agonal death, the timing of the appearance and intensity of coloring of cadaveric spots are determined by the duration of the terminal period. The longer the terminal period, the later the cadaveric spots appear and have a paler color. This phenomenon is due to the fact that during agonal death the blood in the corpse is in a state of varying degrees of coagulation, while during acute death the blood is liquid. In the development of cadaveric spots, depending on the timing of occurrence, three phases are distinguished.
- Hypostasis stage- is the initial stage of development of a cadaveric spot, begins immediately after the cessation of active blood circulation and ends after 12 - 14 hours. At this stage, cadaveric spots disappear when pressed. When the position of the corpse changes (turns over), the spots can completely move to the underlying sections.
- Stage of stasis or diffusion- cadaveric spots begin to transform into it approximately 12 hours after the onset of biological death. At this stage, gradual thickening of the blood in the vessels occurs due to the diffusion of plasma through the vascular wall into the surrounding tissue. In this regard, when pressed, the cadaveric spot turns pale, but does not completely disappear, and after some time it restores its color. When the corpse's position changes (turns over), the spots may partially move to the underlying sections.
- Stage of hemolysis or imbibition- develops approximately 48 hours after the moment of biological death. When pressing on the cadaveric spot, there is no change in color, and when turning the corpse over, there is no change in localization. In the future, cadaveric spots do not undergo any transformations other than putrefactive changes.
Meaning and assessment methods
- cadaveric spots are a reliable, earliest sign of death;
- they reflect the position of the body and its possible changes after death;
- allow you to approximately determine the time of death;
- the degree of severity reflects the speed of death;
- the color of cadaveric spots serves as a diagnostic sign for some poisonings or may indicate the conditions in which the corpse was located;
- they allow us to talk about the nature of the objects on which the corpse was located (brushwood, folds of linen, etc.).
Significance in ascertaining the fact of the occurrence of biological death
The forensic medical significance of cadaveric spots lies not only in the fact that they can be used to determine the duration of death. Their main significance is that they are a reliable sign of death: none of the intravital processes can imitate cadaveric spots. The appearance of cadaveric spots indicates that the heart stopped working at least 1 - 1.5 hours ago, and, as a result, irreversible changes have already occurred in the brain as a result of hypoxia.
Significance in determining the duration of death
The nature of the change in the cadaveric spot when pressed allows forensic experts to roughly establish the duration of death. When analyzing the behavior of a cadaveric spot, it is necessary to take into account the cause of death, the rate of its onset (acute or agonal), and the research methodology. Fairly approximate results can be obtained by applying finger pressure on the spot, so standard methods with a dosed area and pressure force have been developed. Pressure is carried out using a standard calibrated dynamometer. The author of the method, V.I. Kononenko, based on the research conducted, proposed tables for determining the duration of death based on the results of dynamometry of cadaveric spots. The error of the method, according to the author, is within ±2 - ±4 hours. The lack of indication of the confidence interval of the error is a significant drawback of the technique, which reduces its significance for practical application.
In folklore
- From the protocol from the scene of the incident: “Corpse spots the size of 10 and 20 kopeck coins were found on the murdered person, with a total area of three rubles and twenty kopecks.”
- From a letter to Kashpirovsky: “Dear doctor, after your sessions, my cadaveric spots disappeared and the suture from the autopsy dissolved.”
Notes
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Podolyako V.P. Diagnostic capabilities of dynamometry indicators when deciding the issue of how long ago death occurred “Forensic medical examination.” –M., –1998, 1. –p. 3–6.
Stages of formation of cadaveric spots
- Stage hypostasis continues for 12 hours after death. The liquid part of the blood is in the vessels and when pressure is applied to the spots, the blood is squeezed out of the vessels, and after the pressure stops, it quickly fills them again. This leads to the disappearance of cadaveric spots when pressure is applied, as well as to their movement to the underlying sections when the body position changes.
- Stage stasis(diffusion) is observed after 12 hours from the moment of death and lasts up to 24 hours. Cadaveric spots turn pale, but do not disappear when pressed. This is due to the fact that the liquid part of the blood, stretching the wall of the vessel, begins to seep into the tissue. In parallel with this, hemolysis of red blood cells occurs. At this stage, the spots do not move when the position of the corpse changes, but somewhat reduce their intensity.
- Stage imbibition develops on the second day after death. Cadaveric spots are well fixed, do not move, and do not turn pale when pressed, since the soft tissues are saturated with blood.
The time for restoration of the original color of cadaveric spots after pressure with a dynamometer, depending on the duration of death (according to N.P. Turovets, 1962)
| Features of death | Age of death, h | Time required to restore the color of a cadaveric spot, min |
|---|---|---|
| I Asphyxial death | ||
| 1) spot in the hypostasis stage | ||
| in the first phase | Up to 8 | 1 |
| in the second phase | 8-16 | 5-6 |
| 2) spot in the stasis stage | ||
| in the first phase | 16-24 | 10-20 |
| in the second phase | 24-48 | 30-60 |
| II Death after prolonged agony | ||
| 1) spot in the hypostasis stage | ||
| in the first phase | Until 6 | 1-2 |
| in the second phase | 6-12 | 4-5 |
| 2) spot in the stasis stage | ||
| in the first phase | 12-24 | 15-30 |
| in the second phase | 24-48 | 50-60 |
| III Bleeding Corpses | ||
| 1) spot in the hypostasis stage | ||
| in the first phase | Up to 4 | 2 |
| in the second phase | 4-8 | 5 |
| 2) spot in the stasis stage | ||
| in the first phase | 8-24 | 30-40 |
| in the second phase | 24-48 | More than 60 |
Time to restore the original color of cadaveric spots depending on the duration of death (according to A.I. Mukhanov, 1968)
| Time elapsed since death | Time for color restoration of cadaveric spots |
|---|---|
| 2 hours | 3-10 s |
| 4 hours | 5-10 s |
| 6 hours | 10-40 s |
| 8 hours | 20-60 s |
| 10 o'clock | 25 s - 6 min |
| 12 h | 1-15 min |
| 16 h | 2-17 min |
| 18-20 hours | 2-25 min |
| 22-24 hours | 5-40 min |
Time to restore the color of cadaveric spots (in seconds) after dosed pressure on them (according to V.I. Kononenko, 1971) 1
During dosed dynamometry of cadaveric spots, the research conditions are strictly standardized. The surface area of the dynamometer in contact with the skin of the cadaveric spot is 1 cm 2. Pressure is applied with a force of 2 kgf/cm 2 for 3 s. The dynamometer should be positioned perpendicular to the surface of the skin. When cadaveric spots are localized on the posterior surface of the body, pressure is applied in the lumbar region along the midline, and when cadaveric spots are located on the anterior surface of the body, pressure is applied along the midline of the sternum body. The time for color restoration of cadaveric spots is recorded using a stopwatch. Under these conditions, as the author (V.I. Kononenko) notes, the accuracy of determining the duration of death does not exceed ±2–4 hours.
| Prescription of death | 2 hours | 4 hours | 6 hours | 8 ocloc'k | 12 hours | 16 hours | 20 hours | 24 hours |
|---|---|---|---|---|---|---|---|---|
| Acute death: | 9–10 | 14–16 | 20–28 | 38–48 | 55–62 | 78–97 | 121–151 | 113–175 |
| - mechanical asphyxia | 11–12 | 17–21 | 25–31 | 33–49 | 48–66 | 45–74 | 100–174 | - |
| - alcohol poisoning | 8–11 | 14–18 | 18–30 | 33–41 | 59–75 | 83–99 | 76–148 | - |
| - sudden | 8–9 | 13–16 | 18–22 | 28–38 | 45–53 | 81–103 | 145–195 | - |
| Trauma without blood loss | 8–10 | 16–19 | 22–27 | 29–39 | 56–74 | 94–122 | 127–300 | - |
| - with moderate blood loss | 11–13 | 18–21 | 36–43 | 49–58 | 117–144 | 144–198 | - | - |
| - with sudden blood loss | 11–20 | 24–30 | 40–48 | 62–78 | 95–123 | - | - | - |
| Death is agonal | 5–6 | 13–17 | 21–33 | 36–52 | 46–58 | 139–163 | 210–270 | - |
The timing of death, determined by the nature of changes in cadaveric spots (Jaklinski, Kobiela, 1972).
| Prescription of death | Character of cadaveric spots |
|---|---|
| 0-20 min | None |
| 20-30 min | Appear |
| 30-40 min | When pressing on the cadaveric spot, a white field is formed which disappears after 15-30 s |
| 40-60 min | There is an intense coloration of cadaveric spots |
| 1-2 hours | The white field in the area of the cadaveric spot disappears after 30 - 60, and individual spots merge |
| 2-4 hours | Cadaveric spots have a more intense color: they completely turn pale when pressed |
| 4-6 hours | The blanching of cadaveric spots after pressing disappears after 2-3 minutes |
| 6-8 hours | When the position of the corpse changes, cadaveric spots completely disappear and form in new places |
| 8–10 a.m. | When the position of the body changes, the spots partially disappear and form (weaker) in new places |
| 12-1 5 hours | Fixation of cadaveric spots |
| 15 - 24h | Fixation of cadaveric spots |
| 24-72h | Corpse imbibition |
Time to restore the original color of cadaveric spots depending on the stage and duration of death (according to Yu.L. Melnikov and V.V. Zharov, 1978)
Dynamometry indicators in the sacral region with the corpse in the supine position (according to V.P. Podolyako, 1998) 2
| Time of death, h | Dynamometry indicators, s |
|---|---|
| 4 | 9 |
| 6 | 14 |
| 8 | 22 |
| 10 | 32 |
| 12 | 48 |
| 14 | 64 |
| 16 | 98 |
| 20 | 206 |
| 24 | 310 |
Dynamometry indicators in the forehead and sternum when the corpse is positioned face down (according to V.P. Podolyako, 1998) 2
Literature
- Kononenko V.I. Complex physical and chemical study of cadaveric spots (forensic medical assessment of the dynamics of their development): abstract of thesis. dis. ... dr. - Kharkov, 1971.
- Diagnostic capabilities of dynamometry indicators when resolving the issue of how long ago death occurred / Podolyako V.P. // "Forensic-medical examination". - M., 1998. - No. 1. - P. 3-6.
Introduction
Cadaveric phenomena are changes that the organs and tissues of a corpse undergo after the onset of biological death. Cadaveric phenomena are divided into early and late. The early ones include cooling of the corpse, cadaveric spots, rigor mortis, desiccation and autolysis; to the later ones - rotting, skeletonization, mummification, waxing and peat tanning.
Regardless of the mechanism of biological death, it is always preceded by the moment of clinical death. Depending on the speed of death, agonal death and acute death are distinguished. Agonal death is accompanied by a fairly long terminal period. In acute death, the terminal period is short or practically absent (a typical example of acute death is death due to mechanical asphyxia). The onset of death is always preceded by terminal conditions that influence the nature of postmortem changes.
Early cadaveric phenomena
Early cadaveric phenomena are of great forensic medical importance, as they allow solving a number of important problems for the investigation: determining the time of death, the initial position of the corpse, suggesting poisoning with certain toxic substances, etc. Early cadaveric changes include: cooling of the corpse, formation of cadaveric spots and rigor mortis, partial drying of the corpse, cadaveric autolysis.
Cooling the corpse . Due to the cessation of metabolic processes in the body, the temperature of the corpse gradually decreases to the ambient temperature (air, water, etc.). The degree of cooling depends on a number of factors: ambient temperature (the lower it is, the faster the cooling occurs, and vice versa), the nature of the clothing on the corpse (the warmer it is, the slower the cooling occurs), fatness (in obese people, cooling occurs more slowly than in exhausted), causes of death, etc. Parts of the body not covered by clothing cool faster than those covered. The influence of all these factors on the cooling rate is taken into account approximately.
In the literature there is data on the time required to cool the corpse of an adult to ambient temperature: at a temperature of +20C - approximately 30 hours, at +10C - 40 hours, at +5C - 50 hours. At low temperatures (below -4C), cooling turns to freezing. It is better to measure the temperature of a corpse in the rectum. It is generally accepted that, on average, the temperature in the rectum decreases at room temperature (+16-17C) by about one degree per hour and, therefore, by the end of the day it is compared with the ambient temperature. The temperature of the corpse should be measured after a strictly defined time - at the beginning and at the end of the inspection of the crime scene, and then after the corpse arrives at the morgue (taking into account the ambient temperature). It is better to measure the temperature every two hours.
In the absence of a thermometer, the temperature of a corpse can be judged approximately by touching closed parts of the body (open parts of the body cool faster and do not reflect the temperature of the entire corpse). It is better to do this by feeling the armpits of the corpse with the palm of your hand. The degree of cooling of the corpse is one of the reliable signs of death (body temperature below +25C usually indicates death).
Cadaveric spots. They arise due to post-mortem redistribution of blood in the corpse. After cardiac arrest, the movement of blood through the vessels stops, and due to its gravity, it begins to gradually descend into the relatively lower located parts of the corpse, overflowing and expanding the capillaries and small venous vessels. The latter are visible through the skin in the form of bluish-purple spots, which are called cadaveric spots. The higher located parts of the body do not have cadaveric spots. They appear approximately two hours (sometimes 20-30 minutes) after death.
Against the background of cadaveric spots, it is sometimes possible to distinguish prints of clothing and objects that were under the corpse in the form of lighter areas of skin (places pressed by the weight of the body to various objects look paler on the corpse due to the squeezing of blood from them).
When examining a corpse at the scene and in the morgue, attention is paid to the presence and severity of cadaveric spots, their color and the area they occupy (prevalence), disappearance or change in color when pressed. In young healthy people, cadaveric spots are usually well defined, blue-purple in color, located almost over the entire back and partially on the lateral surfaces of the body. In cases of mechanical asphyxia and other types of rapid death, when the blood remains liquid, the cadaveric spots are abundant, diffuse, and blue-purple in color. With large blood loss, as well as in elderly or exhausted people, cadaveric spots usually develop slowly and are weakly expressed, limited in surface area.
Rigor mortis. After death occurs, biological processes occur in the muscles of the corpse, leading first to relaxation, and then (3-4 hours after death) to their contraction, hardening and rigor. In this state, the muscles of the corpse prevent passive movements in the joints, therefore, physical force must be used to straighten the limbs that are in a state of severe rigor mortis. Full development of rigor mortis in all muscle groups is achieved on average by the end of the day. After 1.5-3 days, rigor disappears (resolves), which is expressed in muscle relaxation.
A certain sequence can be traced in the development of rigor mortis; it follows a descending pattern - first, the masticatory muscles of the face undergo rigor, then the muscles of the neck, chest, abdomen, upper and lower extremities. Rigor mortis is allowed in the reverse order (from bottom to top). However, this scheme is correct only under certain conditions. If rigor mortis is artificially disrupted (for example, by applying force to straighten the upper limbs), then in the first 10-12 hours after death it is able to recover, but to a weaker extent; after this period, rigor mortis does not recover, and the muscles remain in a relaxed state. Such a violation of rigor mortis is possible when moving a corpse, when removing clothes from it and other circumstances. Therefore, when examining a corpse at the scene of an incident, it is necessary not only to establish the presence of rigor mortis, but also to compare the degree of its severity in different muscle groups.
The development of rigor mortis accelerates in conditions of high temperature (after 2-4 hours), and at low temperatures it is delayed (after 10-12 hours). Rigor mortis in the corpses of emaciated individuals occurs very quickly, since the mass of the muscles is small and their rigor requires less time than well-developed muscles. There is a rapid development of the process of rigor mortis when glycogen reserves are depleted. The literature describes cases where rigor mortis developed very quickly, while fixing the position of the corpse at the moment of death. More often, such cases are observed with severe mechanical damage to the medulla oblongata (for example, with a gunshot wound). The so-called cataleptic rigor mortis is also possible, which develops very quickly and also fixes the person’s posture at the moment of death.
The presence and severity of rigor mortis is determined by the tightness or relaxation of muscles, or by checking the possibility of movement in large joints.
Corpse desiccation . After death occurs, the body begins to lose fluid and partially dry out. Drying of the skin and visible mucous membranes becomes noticeable several hours after death. First of all, areas covered with the stratum corneum of the skin or moisturized during life dry out. Relatively quickly (5-6 hours after death), the corneas of open or half-open eyes dry out (they become cloudy, acquire a whitish-yellowish color), the mucous membrane and the border of the lips (dense, wrinkled, brownish-red). Such changes in the mucous membranes and skin are sometimes mistaken for intravital deposits due to injury. If the tip of the tongue protrudes from the mouth, it also becomes dense and brown.
Areas of intravital and postmortem deposits (obtained during transportation of a corpse, providing assistance to a victim, etc.) also quickly dry out and have a brownish with a red tint or a “waxy” color. They are called "parchment spots." To establish the intravital or postmortem origin of such “spots,” it is necessary to examine them microscopically. Often, in the first time after death, the affected areas of the skin may not be noticeable. As they dry, they acquire their characteristic appearance. The detection of “parchment spots” of intravital origin may indicate the nature and location of the application of force during mechanical injuries, and, in combination with other data, the nature of violence (for example, compression of the neck with hands during strangulation, damage to the genital area during rape, trauma to the anterolateral surfaces chest as a result of artificial respiration performed on the victim, etc.).
The skin and mucous membranes of newborns, children and the elderly dry out especially quickly. Signs of cadaveric desiccation are used during an external examination of a corpse to ascertain death, when resolving questions about the time of its occurrence, about the intravital or postmortem origin of damage to the skin.
Cadaveric self-digestion (autolysis) ). With the onset of death, the tissues of the corpse undergo self-digestion under the influence of enzymes, especially tissues and organs rich in enzymes: pancreas, adrenal glands, liver, etc. Internal organs, under the influence of autolysis, become dull, become flabby, and are saturated with red-colored blood plasma. The mucous membrane of the stomach, under the influence of digestive juices, undergoes rapid self-digestion.
In infants, such self-digestion can lead to the destruction of the stomach wall and the release of its contents into the abdominal cavity. Sometimes the phenomena of autolysis in the gastrointestinal tract are mistakenly mistaken for the action of destructive poisons (acids, alkalis, etc.).
Conclusion
For a relatively short period of time after death, some physiological processes remain in the corpse: hair and nails continue to grow, the viability of some tissues and organs, blood and bone marrow cells, sperm activity, etc. are preserved. The phenomenon of tissues retaining certain physiological properties is one of the prerequisites for posthumous procurement of blood, corneas, skin, bones, individual internal organs for the purpose of their subsequent transplantation to a living person.
The physiological reactions of the tissues of a dead body have a completely natural tendency to gradually fade, which makes it possible to use these reactions for forensic purposes to determine the duration of death.
List of sources used:
1. Pashinyan G.A., Kharin G.M., Forensic medicine, 2001.
2. Pigolkin I.Yu. Forensic medicine, 2012
3. Samishchenko S.S. Forensic medicine, 1998
After the cessation of cardiac activity, blood and lymph, due to their gravity, begin to gradually descend through the blood and lymphatic vessels into the underlying parts of the corpse. The blood accumulated in these sections passively dilates the venous blood vessels and shines through the skin, forming cadaveric spots.
The localization of cadaveric spots depends on the position of the body of the corpse. They form on the back and posterolateral surfaces of the neck, chest, lower back and limbs when the body is positioned on the back. If lying on the stomach, then cadaveric spots appear on the face, the anterior surface of the chest and abdomen. When hanging, cadaveric spots are found on the limbs (forearms and hands, legs and feet), lower back and abdomen. The areas of the skin of a corpse, pressed by the weight of the body to the planes on which the corpse lies, have a grayish-white color, since the skin vessels in these areas are compressed, there is no blood in them and there are no conditions for the formation of cadaveric spots. This is most often observed in the area of the back of the head, shoulder blades, buttocks, and on the back of the thighs and legs. On cadaveric stains you can see negative imprints of clothing and objects found under the corpse. Thus, the position of the corpse, if it has not changed, predetermines the localization of cadaveric spots.
The severity of cadaveric spots depends on many reasons. Abundant, diffuse cadaveric spots occur, for example, with mechanical asphyxia, in which a liquid state of the blood is observed and the plethora of the internal organs is sharply expressed. With prolonged agony, the formation of red and white bundles occurs, which creates an obstacle to the rapid formation of cadaveric spots. If death was preceded by blood loss, cadaveric spots usually develop slowly and are poorly expressed.
The color of cadaveric spots has important diagnostic value. In case of carbon monoxide poisoning, carboxyhemoglobin is formed, which gives the blood a bright red color, and cadaveric spots accordingly acquire a pronounced reddish-pink tint. In case of poisoning with poisons that cause the formation of methemoglobin (Berthollet salt, nitrites, etc.), cadaveric spots have a grayish-brown tint.
There is a certain pattern in the process of formation of cadaveric spots. It is customary to note three stages in their development: hypostasis, diffusion (or stasis), imbibition.
Stage hypostasis- the initial period of the formation of cadaveric spots, which is caused by the movement of blood into the underlying parts of the corpse. Cadaveric spots at this stage usually appear in the first 2-4 hours after death, sometimes they form later, for example, with heavy blood loss. In the stage of hypostasis, the color of cadaveric spots completely disappears when pressed, as the blood moves from the vessels. A few seconds or a minute after the pressure stops, their original color is restored. When the position of the body changes, the cadaveric spots in the hypostasis stage are completely moved to the underlying sections in accordance with the new position of the corpse.
The second stage of cadaveric spots - diffusion- usually forms within 12-15 hours after death. During this period, lymph and intercellular fluid gradually diffuse through the walls of blood vessels into them, dilute the blood plasma, promoting hemolysis of red blood cells. The liquid part of the blood also diffuses through the wall of blood vessels and permeates the surrounding tissues. Cadaveric spots during this period do not disappear when pressed, but turn pale and slowly restore their original color. When the position of the body changes, cadaveric spots in the diffusion stage can partially move and appear on new underlying areas of the body. Previously formed cadaveric spots remain, but their color becomes somewhat paler.
The third stage of cadaveric spots is hypostatic imbibition, begins to develop towards the end of the day after death, continuing to increase in the following hours. A fluid consisting of lymph, intercellular fluid and plasma leaked from blood vessels permeates the skin. Cadaveric spots at this stage do not disappear and do not turn pale when pressed, but retain their original color; cadaveric spots do not move when the position of the corpse changes.
The change in the nature of cadaveric spots when pressed serves as a guiding sign for experts to establish the duration of death and should be taken into account in conjunction with other data. Typically, pressure is carried out with a specially designed dynamometer, which allows strictly dosed pressure to be applied to the area of the cadaveric spot. The dynamometry results are compared with the data presented in special tables.
In some cases, expert errors may be made when examining cadaveric spots. Under a tight scarf, tie, etc., cadaveric spots do not form, therefore, light stripes formed against the background of cadaveric spots, for example from a collar, can be mistaken for a strangulation groove, which is one of the main signs indicating death from mechanical asphyxia when the neck is compressed loop. Bruises located outside the areas of cadaveric spots are usually easy to recognize. Diagnosis of bruises located on the border of cadaveric spots, and even more so in their zone, presents significant difficulties. Upon careful examination of the bruise, you can see some of its convexity above the general surface, the delineation of the edges and sometimes its shape. Unlike cadaveric spots, the color of bruises does not change when pressed. It is always recommended to make cross-shaped incisions in the area of tissue in which bruising is suspected. In the presence of bruises, as a rule, a hematoma or an area of tissue soaked in blood occupying a limited area is clearly visible, which is absent in cadaveric spots. If necessary, a suspicious area of skin along with subcutaneous tissue is cut out and subjected to microscopic examination. On microscopic preparations of a bruise, loose, densely infiltrating tissue of the reticular layer of the skin and subcutaneous tissue is clearly visible. To objectively determine the presence of bruises against the background of cadaveric spots, putrefactive changes and mummified corpses, a method is proposed, which is based on soaking the area of skin in which the presence of a bruise is suspected in running water, followed by treating it with an acetic-alcohol solution or. In this case, the existing bruises are contoured and acquire a brownish color, with various shades, against the background of yellow-grayish intact skin.
Simultaneously with the appearance of cadaveric spots in the skin, the formation of so-called cadaveric hypostases occurs in the internal organs. In this case, blood accumulates in the underlying parts of the internal organs, which gives them a reddish-bluish color.
If the corpse lies on its back, then the posterior sections of the lungs acquire a pronounced bluish tint, different from other parts of the lung tissue, and some compactness, which is a consequence of cadaveric hypostases. This condition of the lungs can be mistaken for pneumonia. Hypostases in intestinal loops can be regarded as an inflammatory process. A thorough examination of internal organs, as a rule, helps to avoid such errors, and the results of histological studies completely exclude them.
Thus, the presence of cadaveric spots, being a reliable sign of death, serves as one of the sources for resolving the issue of how long ago death was, indicates a change in the initial position of the corpse (before examining it at the place of discovery), and provides guidance in the diagnosis of certain causes of death.
