NecrosisNecrosis

Necrosis is the death of tissue in a Necrosis is the death of tissue in a living body. It is a complete and living body. It is a complete and irreversible ceasing of tissue irreversible ceasing of tissue function. Necrosis is often function. Necrosis is often preceded by necrobiosis. preceded by necrobiosis.

There are such periods in it: There are such periods in it: 1. Paranecrosis, which presents change 1. Paranecrosis, which presents change

similar to necrotic, but they are reversiblesimilar to necrotic, but they are reversible 2. Necrobiosis, which presents irreversible 2. Necrobiosis, which presents irreversible

dystrophic changes, characterized by dystrophic changes, characterized by prevalence of catabolic reactions over prevalence of catabolic reactions over anabolic onesanabolic ones

3. Cell death. It is hard to define the time of 3. Cell death. It is hard to define the time of its occurrenceits occurrence

4. Autolysis or autodigestion, which presents 4. Autolysis or autodigestion, which presents destruction of the dead substance under the destruction of the dead substance under the influence of hydrolytic enzymes of the dead influence of hydrolytic enzymes of the dead cells and macrophagescells and macrophages

Morphologically necrosis is the Morphologically necrosis is the same as autolysis. same as autolysis.

ApoptosisApoptosis

Apoptosis is a specific type of Apoptosis is a specific type of death of death of cells, so-called “programmed death of cells, so-called “programmed death of cells”cells”. At the basis of this process lies . At the basis of this process lies the cell division into parts with the the cell division into parts with the formation of “apoptose bodies” (cell formation of “apoptose bodies” (cell parts, surrounded by membrane), with parts, surrounded by membrane), with subsequent phagocytosis of these subsequent phagocytosis of these bodies by macrophages. bodies by macrophages.

Apoptosis in viral hepatitisApoptosis in viral hepatitis

Necrobiotic and necrotic processes are Necrobiotic and necrotic processes are constantly taking place in the body as the constantly taking place in the body as the manifestation of its normal vital functions. manifestation of its normal vital functions.

Processes of physiologic destruction and Processes of physiologic destruction and regeneration are constant processes in regeneration are constant processes in the bodythe body

Necrosis appears more often and earlier Necrosis appears more often and earlier in the functionally active parenchymal in the functionally active parenchymal structures (functionally stressed structures structures (functionally stressed structures of the myocardium, distal and proximan of the myocardium, distal and proximan parts of the kidney, brain, neurons, etc) parts of the kidney, brain, neurons, etc)

Part of the cell, whole cell, group of Part of the cell, whole cell, group of cells, part of the tissue, part of the cells, part of the tissue, part of the whole organ or even part of the whole organ or even part of the organism may be subjected to organism may be subjected to necrosis. Sometimes necrosis may necrosis. Sometimes necrosis may be defined only microscopically, in be defined only microscopically, in other occasions – microscopically other occasions – microscopically and macroscopically. and macroscopically.

Microscopically signs of necrosis may be Microscopically signs of necrosis may be found in the nucleus and in cytoplasm. But found in the nucleus and in cytoplasm. But sometimes it is difficult to define the state of sometimes it is difficult to define the state of the cell even microscopically, especially at the cell even microscopically, especially at early stage. Microscopic determination of early stage. Microscopic determination of kidney death may be done only kidney death may be done only in 6 hours in 6 hours after stop of blood circulation. So, after stop of blood circulation. So, morphologic changes do not appear at the morphologic changes do not appear at the moment of death, they appear later. Even by moment of death, they appear later. Even by histochemical methods we may determine a histochemical methods we may determine a myocardial infarction only in a few hours myocardial infarction only in a few hours after death of cells. after death of cells.

Microscopically, the most typical signs are: Microscopically, the most typical signs are: Shrivelling of the nucleus. When chromatic Shrivelling of the nucleus. When chromatic

condensation occurs, which leads to condensation occurs, which leads to karyopycnosis; karyopycnosis;

then the nucleus disintegrates into beads then the nucleus disintegrates into beads (karyorrhexis), (karyorrhexis),

and then it dissolves (karyolysis). There are and then it dissolves (karyolysis). There are the successive stages of the process, that the successive stages of the process, that shows the dynamics of hydrolase activation. shows the dynamics of hydrolase activation.

Karyopiknosis and karyorrhexisKaryopiknosis and karyorrhexis

The denaturation and coagulation of The denaturation and coagulation of proteins in the cytoplasm take place. This is proteins in the cytoplasm take place. This is followed by colliquation, and the followed by colliquation, and the ultrastructures are destroyed. The changes ultrastructures are destroyed. The changes may embrace a part of the cell (focal may embrace a part of the cell (focal coagulation necrosis), and this part is coagulation necrosis), and this part is rejected, or it may take place in the whole rejected, or it may take place in the whole cell (cytoplasm coagulation). Coagulation is cell (cytoplasm coagulation). Coagulation is followed by plasmorrhexis, when cytoplasm followed by plasmorrhexis, when cytoplasm disintegrates into beads. Then develops the disintegrates into beads. Then develops the final stage of plasmolysis. final stage of plasmolysis.

The changes in the interstitial The changes in the interstitial substance and fiber structures are substance and fiber structures are swelling and lysis. In the adipose tissue swelling and lysis. In the adipose tissue there is disintegration of neutral fats there is disintegration of neutral fats with formation of fatty acids and soaps. with formation of fatty acids and soaps.

During disintegration of the cell and the During disintegration of the cell and the interstitial substance, tissue detritus is interstitial substance, tissue detritus is formed. Demarcational (with strict formed. Demarcational (with strict borders) inflammation develops around borders) inflammation develops around necrotic focus. necrotic focus.

Macroscopically, necrotic zone is changed, Macroscopically, necrotic zone is changed, too. The consistency, color and smell too. The consistency, color and smell change. Sometimes dead tissue becomes change. Sometimes dead tissue becomes dry and dense (mummification), and dry and dense (mummification), and somethimes it is flaccid and dissoluted somethimes it is flaccid and dissoluted (myomalacia). Often the dead tissue has (myomalacia). Often the dead tissue has yellowish-white color. yellowish-white color.

Sometimes in may have dark red color. Sometimes in may have dark red color. Necrotic region in the uterus, intestine are of Necrotic region in the uterus, intestine are of dirty brown, grayish green or even black dirty brown, grayish green or even black color. At other times necrotic region may be color. At other times necrotic region may be colored by bile. colored by bile.

ClassificationClassification Depending on the cause of necrosis we Depending on the cause of necrosis we

differentiate the following types: differentiate the following types: TraumaticTraumatic ToxicToxic TrophoneuroticTrophoneurotic AllergicAllergic Vascular Vascular

Traumatic necrosis appears as the Traumatic necrosis appears as the result of physical of chemical result of physical of chemical agent’s influence onto the tissue. It agent’s influence onto the tissue. It may be radiation, high and low may be radiation, high and low temperature (burns and frostbites), temperature (burns and frostbites), electric trauma, edges of a woundelectric trauma, edges of a wound

Toxic necrosis occurs after toxin Toxic necrosis occurs after toxin influence of any origin or highly influence of any origin or highly aggressive chemical substancesaggressive chemical substances

Trophoneurotic necrosis occurs after the Trophoneurotic necrosis occurs after the disturbance of nerve trophicitydisturbance of nerve trophicity

Allergic necrosis occurs in sensitized Allergic necrosis occurs in sensitized human organism and is the manifestation human organism and is the manifestation of immediate type hypersensitivity of immediate type hypersensitivity reaction. It is usually fibrinoid necrosis reaction. It is usually fibrinoid necrosis type. type.

Vascular necrosis, which is also called Vascular necrosis, which is also called infarction, occurs in insufficient blood infarction, occurs in insufficient blood circulation as a result of a prolonged circulation as a result of a prolonged spasm, thrombosis, embolism (which can spasm, thrombosis, embolism (which can be angiogenic, ischemic necrosis). be angiogenic, ischemic necrosis).

Depending on the mechanism of Depending on the mechanism of pathogenic factor influence, we pathogenic factor influence, we discern: discern:

direct necrosis, caused by direct direct necrosis, caused by direct influence (as in trauma, toxins), and influence (as in trauma, toxins), and

indirect necrosis, which occurs through indirect necrosis, which occurs through vascular and nervous endocrine vascular and nervous endocrine system. It should be noticed that direct system. It should be noticed that direct necrosis is usually observed in necrosis is usually observed in children.children.

Clinical-morphologic forms of Clinical-morphologic forms of necrosis are defined according to necrosis are defined according to the structural and functional the structural and functional peculiarities of the organs and peculiarities of the organs and tissues where necrosis takes place, tissues where necrosis takes place, as well as the reasons that caused as well as the reasons that caused it, and conditions of development. it, and conditions of development.

We single out these types of We single out these types of necrosis: necrosis:

CoagulationCoagulation Colliquation or liquefactiveColliquation or liquefactive GangreneGangrene Sequester Sequester Infarction (ischemic) Infarction (ischemic)

Coagulation (dry) Coagulation (dry) necrosisnecrosis

This type is characterized by the dead This type is characterized by the dead area being dry, think, grayish-yellow: area being dry, think, grayish-yellow: the tissue is dehydrated. The the tissue is dehydrated. The conditions for the dry necrosis are conditions for the dry necrosis are present in tissues rich in proteins and present in tissues rich in proteins and poor in liquid. For instance, waxy poor in liquid. For instance, waxy necrosis of the muscles in typhus, necrosis of the muscles in typhus, caseous necrosis in tuberculosis, etc. caseous necrosis in tuberculosis, etc.

Coagulative necrosis, infarction of adrenal gland, Coagulative necrosis, infarction of adrenal gland, microscopicallymicroscopically

Coagulative necrosis, Coagulative necrosis, fatty necrosis of pancreasfatty necrosis of pancreas

Coagulative necrosis, Coagulative necrosis, fatty necrosis of pancreas, fatty necrosis of pancreas, microscopicallymicroscopically

Centrolobular necrosis of liverCentrolobular necrosis of liver

Colliquative necrosisColliquative necrosis

Colliquative (wet) necrosis is Colliquative (wet) necrosis is characterized by dissolution of characterized by dissolution of dead tissues. For example, the dead tissues. For example, the focus of gray encephalomalacia. focus of gray encephalomalacia.

Colliquative Colliquative necrosis – necrosis –

abscess of the abscess of the lung, lung,

macroscopicallymacroscopically

Infarction of the brain, macroscopicallyInfarction of the brain, macroscopically

Infarction of the brain, microscopically, low Infarction of the brain, microscopically, low magnificationmagnification

GangreneGangrene Gangrene is a type of tissue necrosis Gangrene is a type of tissue necrosis

assosiated with the environment and assosiated with the environment and changes into black color due to ferric changes into black color due to ferric sulfate formation. There is dry and wet sulfate formation. There is dry and wet gangrene. In dry gangrene the dead gangrene. In dry gangrene the dead tissues dry out in the air, tissues dry out in the air, mummufication occurs. mummufication occurs.

Dry gangrene of the footDry gangrene of the foot

Gangrene of the toe, microscopicallyGangrene of the toe, microscopically

In wet gangrene the dead tissue is In wet gangrene the dead tissue is subjected to action of putrefactive subjected to action of putrefactive microorganisms, becomes microorganisms, becomes edematic, fetid. Wet gangrene edematic, fetid. Wet gangrene develops more often in the tissues develops more often in the tissues rich in liquid (like intestines). rich in liquid (like intestines).

Wet gangrene of lower extremityWet gangrene of lower extremity

Bedsore is a variety of gangrene – Bedsore is a variety of gangrene – it is necrosis of tissues, the surface it is necrosis of tissues, the surface areas of which are under pressure areas of which are under pressure of the body in bed. They most often of the body in bed. They most often occur in the sacrum region or near occur in the sacrum region or near the spinal processes of vertebrae. the spinal processes of vertebrae. It is the trophoneurotic necrosis It is the trophoneurotic necrosis that appears in severely injured or that appears in severely injured or sick persons. sick persons.

Sequester is an area of dead tissue, Sequester is an area of dead tissue, which is not subjected to autolysis, but is which is not subjected to autolysis, but is rejected from the body and located rejected from the body and located among the living tissues. More often among the living tissues. More often sequesters can be found in sequesters can be found in osteomyelitis. The sequestral capsule osteomyelitis. The sequestral capsule and cavity are formed around such a and cavity are formed around such a sequester. This cavity is filled with pus. sequester. This cavity is filled with pus. Sometimes this sequester comes out of Sometimes this sequester comes out of the cavity through a fistula. Sequesters the cavity through a fistula. Sequesters may appear in the place of bedsore and may appear in the place of bedsore and in places of tick bites. in places of tick bites.

InfarctionInfarction Infarction is a type of necrosis which Infarction is a type of necrosis which

appears in the internal organs in the appears in the internal organs in the conditions of acute blood circulation conditions of acute blood circulation dysfunction in a definite place. dysfunction in a definite place. Infarction is the most common type of Infarction is the most common type of necrosis. Its type, size, color and necrosis. Its type, size, color and consistency may vary. Often it has consistency may vary. Often it has wedge-like shape, such infarctions wedge-like shape, such infarctions occur in spleen, kidneys, lungs. occur in spleen, kidneys, lungs.

Some infarctions have irregular Some infarctions have irregular form, they occur in the heart, brain, form, they occur in the heart, brain, intestines. Infarction may affect the intestines. Infarction may affect the major part of the organ or even the major part of the organ or even the whole organ (subtotal or total whole organ (subtotal or total infarction), or it may be only infarction), or it may be only noticed with microscope noticed with microscope (microinfarction). (microinfarction).

By appearance there are three By appearance there are three types of infarction: types of infarction:

White (anemic) White (anemic) White with hemorrhagic crownWhite with hemorrhagic crown Red infarctionRed infarction

White infarctionWhite infarction

White (ischemic, anemic) infarction White (ischemic, anemic) infarction is a region of yellowish white color, is a region of yellowish white color, clearly bordered from the clearly bordered from the surrounding tissues, and is most surrounding tissues, and is most often met in spleen and kidneys. often met in spleen and kidneys.

White infarction with White infarction with hemorrhagic crownhemorrhagic crown

White infarction with hemorrhagic White infarction with hemorrhagic crown is a region of yellowish white crown is a region of yellowish white tissue, surrounded by hemorrhagic tissue, surrounded by hemorrhagic zone. It is formed as a result of vessel zone. It is formed as a result of vessel spasm on the periphery of the spasm on the periphery of the infarction and is followed by its infarction and is followed by its dilatation and development of dilatation and development of hemorrhages. Such infarctions are hemorrhages. Such infarctions are found in the kidneys and myocardium. found in the kidneys and myocardium.

Red infarctionRed infarction

In the red (hemorrhagic) infarction In the red (hemorrhagic) infarction the necrotic region is saturated with the necrotic region is saturated with blood. It is dark red and well blood. It is dark red and well bordered. As a rule, it is found in bordered. As a rule, it is found in the lungs, and rarely in the the lungs, and rarely in the intestines, spleen and kidneys. intestines, spleen and kidneys.

Myocardial infarction has the most Myocardial infarction has the most significant meaning in the clinic. It significant meaning in the clinic. It is met in atherosclerosis and is met in atherosclerosis and hypertensive disease, ischemic hypertensive disease, ischemic heart disease (IHD). heart disease (IHD).

Myocardial infarction, microscopicallyMyocardial infarction, microscopically

Cerebral infarction is more often an Cerebral infarction is more often an ischemic or white infarction, which ischemic or white infarction, which leads to cerebromalacia (or leads to cerebromalacia (or encephalomalacia), the focus of encephalomalacia), the focus of gray cerebromalacia. In the gray cerebromalacia. In the infarction is caused by significant infarction is caused by significant dysfunction, then the necrotic focus dysfunction, then the necrotic focus in the brain is saturated with blood in the brain is saturated with blood and becomes red – focus of red and becomes red – focus of red cerebromalacia. cerebromalacia.

Cerebral infarction, similar to Cerebral infarction, similar to myocardial infarction, more often myocardial infarction, more often occurs on background of occurs on background of atherosclerosis and hypertension. atherosclerosis and hypertension.

Infarction of the brain, macroscopicallyInfarction of the brain, macroscopically

Infarction of the brain, macroscopically, high Infarction of the brain, macroscopically, high magnificationmagnification

In the lungs occurs hemorrhagic infarction In the lungs occurs hemorrhagic infarction in majority of cases. It is well bordered in majority of cases. It is well bordered and has conical shape. The base of the and has conical shape. The base of the cone is nearer to the pleura. Pulmonary cone is nearer to the pleura. Pulmonary hemorrhagic infarction usually occurs on hemorrhagic infarction usually occurs on background of venous congestion. background of venous congestion. Massive hemorrhagic pulmonary Massive hemorrhagic pulmonary infarction may be the cause of adrenal infarction may be the cause of adrenal jaundice. White, anemic, pulmonary jaundice. White, anemic, pulmonary infarction is very rare. It is sometimes infarction is very rare. It is sometimes caused by sclerosis and bronchial artery caused by sclerosis and bronchial artery lumen obliteration. lumen obliteration.

Renal infarction usually is white Renal infarction usually is white (anemic) with hemorrhagic crown. (anemic) with hemorrhagic crown. The necrotic conical part occupies The necrotic conical part occupies either cortical matter or the entire either cortical matter or the entire thickness of parenchyma. thickness of parenchyma.

Renal infarction, macroscopicallyRenal infarction, macroscopically

Renal infarction, microscopicallyRenal infarction, microscopically

In spleen there is usually white In spleen there is usually white infarction, often with reactive infarction, often with reactive fibrinous capsules and subsequent fibrinous capsules and subsequent formation of commissures with the formation of commissures with the diaphragm, parietal layer of the diaphragm, parietal layer of the peritoneum, intestinal loups. peritoneum, intestinal loups. Ischemic infarctions of spleen are Ischemic infarctions of spleen are associated with thrombosis and associated with thrombosis and embolism. embolism.

Infarction of spleen, macroscopicallyInfarction of spleen, macroscopically

In the intestines the infarctions are In the intestines the infarctions are hemorrhagic, quite often they are hemorrhagic, quite often they are subjected to gangrenous lysis, subjected to gangrenous lysis, which leads to perforation of which leads to perforation of intestinal wall and development of intestinal wall and development of peritonitis. peritonitis.

Infarction of small intestine, macroscopicallyInfarction of small intestine, macroscopically

Retinal ocular infarctions are very Retinal ocular infarctions are very rare, same as hepatic, muscular rare, same as hepatic, muscular and bone infarctions. and bone infarctions.

The reasons for development of The reasons for development of infarction are spasms, thrombosis, infarction are spasms, thrombosis, or embolism of the arteries, organ or embolism of the arteries, organ functioning in conditions of blood functioning in conditions of blood circulation insufficiency. The circulation insufficiency. The insufficiency of anastomosis and insufficiency of anastomosis and collateral plays a great role in collateral plays a great role in development of infarction. development of infarction.

The outcome of infarction as any other The outcome of infarction as any other necrotic process depends on the necrotic process depends on the disease peculiarities and the size of disease peculiarities and the size of necrosis. Smaller infarctions undergo necrosis. Smaller infarctions undergo autolysis with subsequent regeneration. autolysis with subsequent regeneration. More often organization and scar More often organization and scar formation take place. Petrification, cyst formation take place. Petrification, cyst formation or purulent lysis are possible. formation or purulent lysis are possible.

The significance of infarction depends The significance of infarction depends on its size, and the organ where it on its size, and the organ where it takes place. takes place.

Termination of necrosisTermination of necrosis

As a rule, a reactive (demarcational) As a rule, a reactive (demarcational) inflammation takes place around the inflammation takes place around the necrotic region; the border zone is called necrotic region; the border zone is called demarcational zone. If the dead tissue is demarcational zone. If the dead tissue is replaced by the connective tissue, this replaced by the connective tissue, this process is called encapsulation. process is called encapsulation. Sometimes calcium salts may be found in Sometimes calcium salts may be found in the necrotic zone (petrification). the necrotic zone (petrification).

With time, bone may be formed in With time, bone may be formed in the region of petrification the region of petrification (ossification). Sometimes a cyst if (ossification). Sometimes a cyst if formed in the region of the formed in the region of the resorbed necrosis. The purulent resorbed necrosis. The purulent lysis of tissues is the most lysis of tissues is the most unfavorable termination of unfavorable termination of necrosis. necrosis.

The importance of necrosis is The importance of necrosis is defined by its nature, that is “local defined by its nature, that is “local death”. Necrosis of vitally important death”. Necrosis of vitally important organs often leads to death. Often organs often leads to death. Often necrosis leads to decrease of necrosis leads to decrease of organ function, to intoxication. organ function, to intoxication. Purulent lysis may be the cause of Purulent lysis may be the cause of purulent inflammation of serous purulent inflammation of serous membranes and sepsis. membranes and sepsis.

Necrobiotic processes are normal Necrobiotic processes are normal processes in biology. processes in biology. Integumentary epithelium of the Integumentary epithelium of the skin, epithelium of digestive, skin, epithelium of digestive, respiratory and urogenital tracts respiratory and urogenital tracts constantly dissolutes and constantly dissolutes and regenerates. regenerates.

DeathDeath Death as biological notion is Death as biological notion is

manifestation of irreversible changes in manifestation of irreversible changes in vital activity of the organism. When vital activity of the organism. When death occurs, the organism becomes a death occurs, the organism becomes a corpse. corpse.

Depending on the reason leading to Depending on the reason leading to death, there are discerned physiological death, there are discerned physiological (or natural) death, death by violence and (or natural) death, death by violence and death from disease. death from disease.

Physiological (or natural) death Physiological (or natural) death usually takes place in the elderly as usually takes place in the elderly as a result of natural (physiologic) a result of natural (physiologic) aging. The term of human life has aging. The term of human life has not yet been defeined, however it not yet been defeined, however it may not be less than 150 years. may not be less than 150 years. Gerontology dealds with the Gerontology dealds with the problems of aging, and geriatry problems of aging, and geriatry deals with the diseases of the deals with the diseases of the elderly. elderly.

Death by violence takes place as a Death by violence takes place as a result of somebody’s abuse over a result of somebody’s abuse over a person. It may be a murder, person. It may be a murder, suicede, death from trauma, suicede, death from trauma, accidents. Forensic medicine accidents. Forensic medicine studies death by violence. studies death by violence.

Death from disease occurs as result of Death from disease occurs as result of incompatibility of life with the changes incompatibility of life with the changes in the body that are caused by in the body that are caused by pathological processes. Usually death pathological processes. Usually death from disease progresses slowly and from disease progresses slowly and may be prognosed with high level of may be prognosed with high level of probability. If death occurs probability. If death occurs unexpectedly, it is termed unexpectedly, it is termed “spontaneous death”. If death occurs in “spontaneous death”. If death occurs in a seemingly healthy person, it is called a seemingly healthy person, it is called “sudden death”. “sudden death”.

Death is not a momentary process. Death is not a momentary process. It is stretched in time. There is It is stretched in time. There is clinical and biological death. clinical and biological death.

Clinical deathClinical death Clinical death is a reversible process. Clinical death is a reversible process.

At its base lies state of hypoxia in At its base lies state of hypoxia in connection with blood circulation arrest. connection with blood circulation arrest. It is preceded by agony, lasting from It is preceded by agony, lasting from minutes to hours. Agony is referred to minutes to hours. Agony is referred to terminal conditions. Reanimatology terminal conditions. Reanimatology deals with those issues. deals with those issues.

Biological deathBiological death Biological death presents irreversible Biological death presents irreversible

changes in the organism and beginning changes in the organism and beginning of autolytic processes in it. However, of autolytic processes in it. However, death of cells and tissues does not take death of cells and tissues does not take place at the same time. The central place at the same time. The central nervous system (CNS) dies first (5 nervous system (CNS) dies first (5 minutes). In other organs and systems minutes). In other organs and systems this process is prolonged for hours and this process is prolonged for hours and sometimes days. sometimes days.

When clinical death occurs, there are When clinical death occurs, there are several symptoms or signs that may be several symptoms or signs that may be observed: observed:

Brunatis symptom is the agony stage sign in Brunatis symptom is the agony stage sign in severe diseases. It is opacification of the severe diseases. It is opacification of the cornea. cornea.

Davis symptom is a possible death sign Davis symptom is a possible death sign (non-pulsating empty arteries on palpation, (non-pulsating empty arteries on palpation, with pale or yellowing spots over them)with pale or yellowing spots over them)

Hering’s symptom is a death sign, presents Hering’s symptom is a death sign, presents a light humming noise, that may be heard a light humming noise, that may be heard over the lower end of the breastbone, right over the lower end of the breastbone, right after ceasing of heart beat. after ceasing of heart beat.

Larchais symptom - when white membranes Larchais symptom - when white membranes of the eyes not covered by eyelids become of the eyes not covered by eyelids become dull and pale gray due to drying in one hour dull and pale gray due to drying in one hour after death. after death.

Levasser’s symptom - when a scratch does Levasser’s symptom - when a scratch does not bleed, there is no hemorrhagenot bleed, there is no hemorrhage

Monteverde’s symptom – when Monteverde’s symptom – when subcutaneus injection of ammonia does not subcutaneus injection of ammonia does not evoke any reaction evoke any reaction

Beloglazov-Rino’s symptom – pressure onto Beloglazov-Rino’s symptom – pressure onto the eye-ball of a corpse leads to constant the eye-ball of a corpse leads to constant deformation of pupil shape (which is deformation of pupil shape (which is temporal in living organism)temporal in living organism)

Cako symptom – so-called “reaction of Cako symptom – so-called “reaction of sirviving tissues”. On percussion some sirviving tissues”. On percussion some definite points of muscles and tendons can definite points of muscles and tendons can contract and move at corresponding joints contract and move at corresponding joints within 2 hours after onset of clinical death. within 2 hours after onset of clinical death.

All of those symptoms are not very reliable. All of those symptoms are not very reliable.

There are pathoanatomical signs of death There are pathoanatomical signs of death and post-mortem changes. They are: and post-mortem changes. They are:

Cooling down of corpse (algor mortis)Cooling down of corpse (algor mortis) Rigor mortis (rigidity of corpse)Rigor mortis (rigidity of corpse) Drying up (or shriveling) of corpseDrying up (or shriveling) of corpse Redistribution of bloodRedistribution of blood Postmortem lividityPostmortem lividity Postmortem decompositionPostmortem decomposition

Cooling down or algor mortis develops in Cooling down or algor mortis develops in connection with ceasing of heat production connection with ceasing of heat production in the organism. If before death the body in the organism. If before death the body temperature was very high or in agony temperature was very high or in agony period the patient had crapms or seizures, period the patient had crapms or seizures, the cooling down will take place slowly. the cooling down will take place slowly.

In some cases (tetanus-like death) In some cases (tetanus-like death) temperature may even rise in a hew hours temperature may even rise in a hew hours immediately after death. immediately after death.

Rigor mortis is muscular stiffening. It is caused Rigor mortis is muscular stiffening. It is caused by disappearance of adenosine triphosphate by disappearance of adenosine triphosphate and accumulation of lactic acid in muscles after and accumulation of lactic acid in muscles after death of the body. Rigor mortis usually death of the body. Rigor mortis usually develops in 2-5 hours after death, and by the develops in 2-5 hours after death, and by the end of 24 hours it extends to all muscles. It is end of 24 hours it extends to all muscles. It is preserved for 2-3 days and then disappears in preserved for 2-3 days and then disappears in the same consequence. If rigor mortis was the same consequence. If rigor mortis was broken on purpose it does not restore. Rigor broken on purpose it does not restore. Rigor mortis is well manifested in corpses with well-mortis is well manifested in corpses with well-trained muscles and in cases when death trained muscles and in cases when death occurs with spasmodic seizures. occurs with spasmodic seizures.

Drying up or shrivelling of the corpse occurs Drying up or shrivelling of the corpse occurs as result of fluid evaporation from body as result of fluid evaporation from body surface. It may occur in some skin areas, or surface. It may occur in some skin areas, or the whole body may be drying up the whole body may be drying up (mummification). (mummification).

Redistribution of blood is manifested when Redistribution of blood is manifested when all the veins are full-blooded and arteries are all the veins are full-blooded and arteries are empty. Blood coagulation takes place in empty. Blood coagulation takes place in larger vessels. larger vessels.

Postmortem lividity appears as result of Postmortem lividity appears as result of blood flowing down into lower parts of the blood flowing down into lower parts of the body as it lies. In 3-6 hours dark violet body as it lies. In 3-6 hours dark violet livedos (spots) turn pale on pressure livedos (spots) turn pale on pressure (postmortem hypostasis). Later in hemolysis (postmortem hypostasis). Later in hemolysis the region of hypostasis is infiltrated with the region of hypostasis is infiltrated with plasma colored with hemoglobin. These plasma colored with hemoglobin. These spots have pinkish red color and do not spots have pinkish red color and do not disappear on pressure (postmortem disappear on pressure (postmortem imbibition). imbibition).

Postmortem putrefaction is connected with Postmortem putrefaction is connected with autolysis processes. They are followed by autolysis processes. They are followed by putrefactive processes. Gases are formed putrefactive processes. Gases are formed (postmortem emphysema). It is very difficult (postmortem emphysema). It is very difficult to slow the process of cadaveric to slow the process of cadaveric putrefaction. Freezing is the only reliable putrefaction. Freezing is the only reliable method. method.