POSTMORTEM CHANGES (cadaveric changes, cadaveric phenomena) — set of the changes developing after death as a result of the termination of vital signs of an organism.
Item and. livors mortis, a cadaveric spasm, drying, an autolysis are shown in various terms therefore they are conditionally subdivided on early (cooling of a corpse) and late (transformativny, or transforming), as a result to-rykh a corpse is exposed to decomposition and destruction (an autolysis, rotting) or natural preservation (to mummification, saponification, a peat tanning, freezing). P.'s development and. depends on character of clothes, conditions of the environment, degree of blood loss, development of hypodermic cellulose, a cause of death, possible associated diseases and conditions of an organism, some other exogenous and internal causes.
Patterns of emergence and development, account loudspeakers P. and. use in forensic medicine for diagnosis of the fact death (see) and definitions of a limitation period of its approach, establishment of an initial pose of a corpse and its possible change in the posthumous period, for approximate judgment of a cause of death and permission of nek-ry other special questions. Item and. have essential value and for studying of terms of experience of these or those bodies and fabrics during the definition of suitability them for transplantation (see. Transplantation ). Knowledge of features of decomposition of a corpse is necessary for carrying out differential diagnosis of putrefactive changes with intravital damages or diseases. So, the vystupaniye of language from an oral cavity under pressure of the accumulated gases imitates one of symptoms of mechanical asphyxia; bulging on skin of a corpse owing to amotio of epidermis and accumulation of liquid reminds a burn of the II degree; greenish color the putrefactive venous network is similar to a so-called figure of a lightning; flowing of gastric contents in respiratory tracts imitates intravital aspiration of emetic masses; release of the bloody liquid which is formed during the rotting is similar to uterine, gastric or pulmonary bleeding. The putrefactive imbibition and consolidation of lungs should be differentiated with pneumonia, and changes of a mucous membrane of a stomach, its seeming hypostasis and red-brown color with the changes which are found at poisonings. Poisoning with caustic poisons can imitate a rupture of a wall of a stomach under the influence of putrefactive gases. The putrefactive imbibition, consolidation and red-brown color of a pancreas can remind morfol, a picture of hemorrhagic pancreatitis. Foamy blood due to penetration into vessels of putrefactive gases is similar to blood at air embolisms (see). Adjournment of crystals of salts oksifenilammoniynopropionovy to - you on fastion and serous covers of internals should be distinguished from the loss of crystals accepted during lifetime of poison.
Knowledge of patterns of development of P. and. has essential atheistic value, helping exposure of the superstitions connected with dying and death, burial of so-called seeming dead. Movement, change of a pose of a corpse in a coffin is explained by non-simultaneity of process of rotting in various parts of a body, different degree of manifestation in them cadaveric emphysema. The posthumous childbirth which is followed, as a rule, by an ectropion of a uterus is caused by increase in pressure in an abdominal cavity due to formation of putrefactive gases. Knowledge of patterns of formation of an adipocere and mummification of corpses allows to exclude a divine origin of the sacred relics used by churchmen as subject to worship of believers.
Early postmortem changes
Cooling of a corpse. Body temperature after the termination of cordial activity during the first tens of minutes usually remains at one level, then begins to decrease gradually — on average on 1 ° in 1 hour at a temperature of ambient air of 16 — 18 °. Over time due to evaporation of moisture from the surface of skin temperature of a corpse reaches values on 0,5 — 3 ° lower than temperature of an ambient air if it less — 4 °, cooling turns into freezing. Speed and extent of cooling are influenced by the ambient temperature, humidity and wind force during the finding of a corpse on air, character of the environment, a pose of a corpse, degree of fatness, a cause of death. At deaths door from tetanus, sepsis, a typhus, nek-ry poisonings body temperature after a cardiac standstill for short time can increase to 40 — 41 ° and more. Very quickly there occurs cooling of corpses of newborns due to tenderness and a subtlety of epidermis, the bigger surface of skin in relation to the weight (weight) of a body. Registration of cooling of a corpse in court. - medical practice make by numerous rectal thermometry or deep electrothermometry of a liver. Body temperature of less than 20 ° is a reliable sign of death. Taking into account dynamics of cooling of a corpse in each case it is possible to establish duration of the posthumous period.
Livors mortis — a peculiar coloring of skin due to running off and accumulation of blood in the below-located body parts. They begin to form in 2 — 4 hours after the termination of cordial activity. Degree of their expressiveness depends on rate of dying of an organism; so, plentiful diffuse saturated livors mortis are characteristic of bystry death (mechanical asphyxia, acute coronary insufficiency); scanty pale — for death from plentiful blood loss, at a long agony, sharp exhaustion of an organism. Usually livors mortis have blue-violet or crimson-violet coloring. Scarlet, their red color indicates poisoning with carbon monoxide, hydrogen sulfide, cyanides, death from overcooling of an organism; grayish-brown — on poisoning with metgemoglobinobrazuyushchy poisons (potassium chloride, nitrites). It is accepted to distinguish 3 stages of development of livors mortis: a hypostasis (from their emergence to 12 — 14 hours of the posthumous period), diffusion, or staz (of 12 — 14 hours until the end of the first days), and an imbibition (more than one days). The hypostasis is characterized by overflow of veins blood, staz — hemolysis of erythrocytes and diffusion of a liquid part of blood through a wall of vessels, the beginning of a prokrashivaniye of surrounding fabrics a blood pigment; an imbibition — end of a prokrashivaniye of fabrics blood. During the pressing by a finger (dynamometer) on a livor mortis in a stage hypostasis (see) it completely disappears and it is recovered after unloading in several seconds again. At a turning of a corpse livors mortis in this stage completely disappear and again are formed in underlying body parts. In a stage of a staz livors mortis during the pressing turn pale, but do not disappear completely, initial coloring is recovered slowly (within several minutes). At a turning of a corpse livors mortis remain as on former places, and are formed on new, underlying body parts (tsvetn. fig. 4). In a stage imbibition (see) livors mortis do not change coloring during the pressing, at a turning of a corpse remain only in places of their initial education. Along with emergence of livors mortis on skin there is a formation of so-called cadaveric gipostaz in underlying departments of internals that gives them at the expense of the accumulated blood a reddish and cyanotic shade. Existence of livors mortis is a reliable sign of a cardiac standstill, and their character allows to judge prescription of approach of death, indicates change of initial provision of a corpse, orients in diagnosis of nek-ry causes of death.
Cadaveric (muscular) spasm — the peculiar consolidation and shortening of skeletal muscles creating an obstacle for the passive movement in joints and also smooth muscles of internals and a muscle of heart. The cadaveric spasm begins to be shown externally 2 — 4 hours later after the termination of heartbeat, reaches the maximum expressiveness by the end of 1 days of the posthumous period and is spontaneously allowed on 3 — the 4th days. Disturbance of resynthesis of ATP and accumulation milk to - you is its cornerstone. Full splitting of ATP in muscles comes only later 10 — 12 hours after a cardiac standstill therefore the cadaveric spasm which is artificially broken till this time completely is recovered that needs to be considered in court. - medical practice (a possibility of imitation of intravital actions with a criminal intent). The cadaveric spasm develops quicker at higher (but not higher than 50 °) temperature of an ambient air and its low humidity, at persons with well developed muscles, during the vigorous muscular work preceding death, spasms, poisonings with the substances operating on c. N of page (strychnine, Pilocarpinum, to-tami). The sepsis, serious debilitating diseases preceding death some poisonings (Chlorali hydras, a death angel) cause weakness of expressiveness or total absence of a cadaveric spasm. In rare instances (destruction of substance of a myelencephalon, the sharp spasms preceding death) there can be a so-called cataleptic cadaveric spasm developing at the time of a cardiac standstill as a result of direct transition of intravital contractures to a cadaveric spasm and keeping, thus, a pose of the person at this moment. In forensic medicine the cadaveric spasm is determined by existence of resistance to the passive movements in joints of extremities, muscles of a neck and chewing muscles. The cadaveric spasm is a reliable sign of death, allows to judge a limitation period of its approach, an initial pose, in nek-ry cases about a cause of death.
Drying due to noncompensated evaporation of moisture begins with the surface of skin right after approach of death, however visually it is shown only several hours later. Process begins on the sites deprived of epidermis i.e. on mucous membranes of eyes, lips, generative organs, or on those places where epidermis is thinnest — a scrotum, trailer phalanxes of fingers. The first sign of drying and, therefore, a reliable sign of death is formation of dim yellowish-gray or brownish sites of drying of scleras of eyes in the form of the isosceles triangles turned by the basis to an iris of the eye, top to corners of eyes — Larcher's spots. Especially clearly they are shown if eyes after death remained open. In the subsequent are condensed, shrivel, get brownish, violet coloring and other drying-up sites. Quickly drying and those sites where epidermis was injured soon after approach of death develops; on these places «pergament» spots — the dense ocherous sinking-down sites of skin with the translucent red vessels form. Formation of pergament spots is possible also on the unimpaired skin in the places which underwent a long pridavlivaniye. Process of drying (see. Mummification ) accelerates in the conditions of the elevated temperature and the lowered humidity of an ambient air. Usually it is limited to separate body parts, but in special conditions of the environment drying can be total that leads to mummification of a corpse (tsvetn. fig. 7 and 8).
Autolysis — disintegration of structures of an organism under the influence of hydrolases in connection with the coming ambassador of death disorganization of fermental systems and shift of pH in the acid party. Externally this process is characterized by a gradual softening and fluidifying of bodies and fabrics, expressiveness to-rykh depends on quantitative contents in them proteolytic enzymes. High content of lizosomalny enzymes in a pancreas, adrenal glands, a spleen, a liver causes emergence of initial signs of an autolysis in these bodies. Blood is exposed to quite bystry autolysis — posthumous hemolysis is essentially manifestation of an autolysis. In a stomach and a small bowel the digestive juices containing pepsin, trypsin and other enzymes have the leading value. Their action after death addresses on own mucous membrane which lost protective barrier functions. Thus, occurs self-digestion (see) a mucous membrane, intensity to-rogo is in direct dependence on the stage of digestion taking place just before death. Self-digestion is most often limited to a mucous membrane, but at babies walls of a stomach and a gut can be involved in process of an autolysis. Under nek-ry conditions the gastric juice can get into a gullet, a throat, even a trachea and to cause an ezofagomalyation, a «acid» pneumomalacia.
Late postmortem changes
Rotting — difficult biol, the process caused by the numerous microorganisms which are intensively breeding in a corpse and allocating a large amount of the proteolytic enzymes decomposing organic matters, first of all proteins, fats and carbohydrates. Putrefactive decomposition (transformation) of a corpse can proceed in two forms. The first is observed when rotting happens as the recovery reactions which are followed by formation of the simple volatile hydride compounds having, as a rule, off-flavor. This process is considered to be actually rotting (see). The second form takes place when decomposition goes as oxidation or combustion with formation of a number of acidiferous connections. This process is called decay. Usually putrefactive decomposition of a corpse consists of 3 stages: formations of gases, softenings of fabrics with the subsequent their imbibition and their full fluidifying. In the course of rotting both aerobic, and anaerobic saprophytes take part, pathogenic microbes usually quickly perish. Therefore consider that infection inf. diseases at necropsy in a stage of rotting it is impossible. At the same time in the course of rotting some toxic agents of group of ptomaine (putrestsin, pentamethylenediamine) called by ptomaine that demands a certain care at a research of the putrefactive changed corpses are formed. Speed and features of rotting depend on a number of external and internal factors. High (apprx. 40 °) the ambient temperature, the increased humidity promote development of process of rotting. Rotting quickly develops on air, more slowly — in water and even more slowly in the soil. At a temperature below 0 ° and higher than 50 — 60 °, sufficient inflow of a dry air rotting can sharply be slow to stop at all. Considerably process of rotting at deaths door from sepsis, purulent diseases or inf accelerates. diseases. Also the sex, age, degree of food matter. Corpses of newborns decay quicker, old men — more slowly. Corpses of men decay quicker, than corpses of women, corpulent people quicker, than thin. At deaths door from asphyxia, a solar and thermal shock, an electric trauma process of rotting develops quickly, at deaths door from the debilitating diseases connected with dehydration at alcoholic poisonings, arsenic, quinine, cyanides, corrosive sublimate, etc. — in a slowed-up way. Development of rotting significantly is late in case of the use by the person shortly before death of a large number of antibiotics (a tetracycline row) and sulfanamide drugs. Already in 3 — 6 hours after approach of death rotting begins to develop in a large intestine where a large amount of putrefactive gases is formed, a row to-rykh (hydrogen sulfide, marked ethane thiol) has specific off-flavor. Hydrogen sulfide, connecting to hemoglobin of blood, forms the sulfogemoglo-bin and ferrous sulfide having dirty green-brown coloring. In the beginning (1 — the 2nd days) greenish coloring appears in ileal areas, then on the course of large vessels, forming putrefactive venous network (tsvetn. fig. 6). On 5 — the 7th days putrefactive gases, getting into hypodermic cellulose, as if inflate it, leading to development of cadaveric (putrefactive) emphysema, especially in a face, lips, mammary glands, a stomach, a scrotum, extremities. At palpation of skin of such corpse sharp crepitation is felt. On 10 — the 12th days all skin gets dirty-green coloring. Further epidermis begins to exfoliate with bulging with serous and bloody contents, after a gap to-rykh the wet burovatokrasny surface is bared (tsvetn. fig. 5). From internals the stomach, intestines, lungs, a liver, a brain, a pancreas, kidneys, adrenal glands, heart most quicker are exposed to rotting. Bodies become as if «foamy», get brownish-red, and then brownish-green or dirty-green coloring (a putrefactive imbibition), are liquefied. At gistol, a research in fabric of these bodies it is not possible to reveal parenchymatous elements. Gradually process of rotting extends also to other bodies and fabrics, and the nonpregnant uterus, a prostate, sheaves, cartilages most longer remain.
Depending on conditions of burial (nature of the soil, its pollution, humidity) approximately in 2 years of fabric and bodies take a form of the breaking-up homogeneous dirty-gray mass, edges it is gradually dissolved and washed away by water of the soil. Bones of a skeleton can remain vaguely long time. The putrefactive changed corpses can be an object court. - medical examinations, at the same time extent of putrefactive decomposition is not an obstacle for court. - medical researches of a corpse (see. Exhumation ). Even at sharply expressed decomposition of a corpse various damages, especially bones, traces of a shot on skin, etc. can be revealed that has important expert and diagnostic value.
The preserving forms can cause preservation of outward (freezing) or the specific features allowing to carry out identification of the personality (see) to reveal features of the injuries received earlier, etc. To such types of P. and. carry a through cure of a corpse or its parts (natural mummification), saponification of a corpse, or saponification (see. Adipocere ), peat tanning, etc. (tsvetn. fig. 9).
Peat tanning arises at hit of a corpse to the peat bogs and soils containing humic to - you and other acid, tannic and cementitious matters. At the same time skin of a corpse is condensed, gets dark-brown coloring, internals decrease in sizes. Under the influence of humic to - t mineral salts are dissolved and washed away from a corpse therefore bones get a consistence of cartilages and easily knifed. At gistol. a research find full safety of a structure of skin and muscles, nervous tissue. In peatbogs corpses remain vaguely long. At their court. - a medical research it is possible to define received during lifetime of damage. Also long corpses in water with the high content of salts, in oil remain.
Other postmortem changes
To P. and. a corpse also destruction by his representatives vegetable (mold) and an animal belongs (insects, rodents, small and large predators, etc.) world. A mold, mold fungi can grow on corpses or their parts in the presence of enough moisture. Participation pleseny in destruction of a corpse slightly, but some of their types can give valuable instructions on the place where there was a corpse, and prescription of approach of death. From insects flies have the greatest value. Soon after death they begin to postpone around natural foramens, eyes, wounds a large number of eggs in the form of white grains. In 1 days the larvae emitting the high-speed proteolytic enzyme melting soft tissues of a corpse are formed of them. Getting in a corpse, they continue the development during 1,5 — 2 weeks then dolls are formed, and in 2 weeks — flies. Thus, biol, the development cycle of flies makes 3 — 4 weeks, however at an elevated temperature it can accelerate to 2 weeks (at a temperature of ambient air of 30 °), at low — to be extended considerably. Under favorable conditions (air temperature 15 — 20 °) flies can destroy completely soft tissues of a corpse of the newborn for 1,5 — 2 weeks, the adult in 1 — 1,5 month. Can damage a corpse also other insects, in particular ants (can skeletirovat a corpse of the adult within 2 months), bugs, mites. Consider that soft tissues and fat of the corpses which are in the earth within 1 — 3 month eat sarcophagi, 2 — 4 months — khapra beetles, 8 months — sylphs. Cartilages and ligaments are destroyed by mites.
Quite often rodents, especially rats, and also wolves, jackals destroy corpses, cats and dogs are more rare. Damages to these cases usually have irregular shape with torn, scalloped, bloodless edges, on to-rykh traces of teeth are well visible. In an aqueous medium corpses damage some species of predatory fishes, crayfish, bloodsuckers. Destroy corpses as well some birds, napr, crows. Damages of corpses by animals are complicated by conducting examination, but is not an obstacle for court. - medical researches of a corpse.
See also Corpse .
Bibliography: Avdeev M. I. Forensic medical examination of a corpse, M., 1976; L at sh N and to about in E. F. and Shapiro N. A. Autoliz, Morphology and mechanisms of development, M., 1974; Millers Yu. JI. and Zharov V. V. Medicolegal definition of time of approach of death, M., 1978; The Multivolume teukovodstvo on pathological anatomy, under the editorship of A. I. Strukov, t. 1, page 636, M., 1963; Strukov A. I. and Serov V. V. Pathological anatomy, M., 1979; Forensic medicine, under the editorship of V. M. Smolyaninov, M., 1980.
I. V. Buromsky, M. N. Lantsman.