FIXATION OF POST-MORTEM STAINING

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FIXATION OF POST-MORTEM STAINING : 

FIXATION OF POST-MORTEM STAINING Dr. JINESH P. S. 06 -06-2012 1

OUTLINE OF PRESENTATION: 

OUTLINE OF PRESENTATION DEFINITION MECHANISM TIME OF APPEARENCES EXTENT & DISTRIBUTION MECHANISM OF FIXATION DEMONSTRATION DIFFERENCES WITH CONTUSION INTERNAL LIVIDITY DIFFERENCES WITH CONGESTION REFERENCES 2

POST-MORTEM STAINING: 

POST-MORTEM STAINING POST-MORTEM HYPOSTASIS POST-MORTEM LIVIDITY LIVOR MORTIS CADAVERIC LIVIDITY SUGGILATIONS VIBICES DARKENING OF DEATH 3

POST-MORTEM STAINING: 

POST-MORTEM STAINING The bluish-purple or purplish-red discoloration that results from settling of blood to the dependent portion of the body after death Hypostasis means ‘passive congestion of an organ or part’ 4

TIME OF APPEARANCE: 

TIME OF APPEARANCE After death, the vessels will lose the tone and blood will gravitate into them, imparting a discoloration of the subjacent area It begins to develop after the heart stops beating and becomes more intense with time First appears in patches By about 3 hours, it becomes confluent Becomes permanent and fixed by 6 to 12 hours 5

TIME OF APPEARANCE: 

May appear faster when agonal period is prolonged, in persons dying of narcotic poisoning or where the circulation becomes stagnant prior to death May be unduly delayed in death due to anaemia, acute haemorrhage or introduction of huge saline transfusion prior to death TIME OF APPEARANCE 6

EXTENT & DISTRIBUTION: 

EXTENT & DISTRIBUTION Extent of lividity depends upon the amount and fluidity of blood Blood is spontaneously coagulable in all cases of sudden death Spontaneous coagulability of blood may disappear as shortly as 1.5 hours after death Fribinogen is absent from postmortem blood samples that have lost their power of spontaneous coagulation 7

PowerPoint Presentation: 

Fibrinolysin obtained from postmortem blood acts only on fibrin not on fibrinogen Fibrinolysin acts by becoming absorbed on to the clot as it is being formed and it is later released to solution when the clot lyses It is not effective when added to a clot already formed Fibrinolysin is produced by endothelial lining of vascular channels 8

DISTRIBUTION: 

Distribution of hypostasis depends upon the posture of body after death In a supine body – on back Blood is pushed out of the areas of the body that are lying on the ground or on other objects , resulting in patches of contact pallor - back of head, back of shoulders, buttocks, back of thigh and calves PMS will not seen in parts that have been compressed by tight clothing like brassiere, terminal parts of socks - it may occur as strips or bands called vibices DISTRIBUTION 9

This man’s arm was in complete rigor against his body. When the arm is moved, the absence of lividity is apparent where the arm was in contact with the skin: 

This man’s arm was in complete rigor against his body. When the arm is moved, the absence of lividity is apparent where the arm was in contact with the skin 10

P M S IN HANGING: 

P M S IN HANGING In a hanging body – lower limbs, surrounding genItalia , hands & distal portion of arms; gradually fades proximally Lividity is evident in the lower face in hanging because the ligature tightly encircles the neck If suspension is prolonged, the accumulation of blood may create enough pressure to rupture subcutaneous cappillaries and produce petechial haemorrhages in the skin 11

P M S in DROWNING: 

P M S in DROWNING Found on face, the upper chest, hands, lower arms, feet & lower legs when the body floats in still water If the body constantly changing position due to forceful current of water, staining may not develop 12

MECHANISM OF FIXATION : 

Rigor mortis setting in the muscle fibres compresses the vessel and prevents the flow of blood even if position of the body is changed If the position of the body is changed before 6 – 12 hours, the staining disappear from original area and reappear in new dependent parts Different patterns of PMS in same body are proof that the body has been moved MECHANISM OF FIXATION 13

DEMONSTRATION OF P M S: 

DEMONSTRATION OF P M S As livor is developing, pressure on area of livor for several seconds pushes the blood out of the capillaries and the area will blanche Once livor is fully developed, it becomes fixed and will no longer blanche with pressure 14

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COLOUR OF HYPOSTASIS : 

COLOUR OF HYPOSTASIS Usually – reddish purple Colour depends upon the state of oxygenation at about the time of death Those who dying hypoxic states have darker tint due to presence of reduced Hb in the cutaneous vessels When death is due to hypothermia colour may be pink due to presence of much of OxyHb as the tissues, due to reduced metabolism Difficult to see in hemorrhagic shock, exasanguination and anemia More difficult to see in dark skinned persons 16

COLOUR OF HYPOSTASIS : 

In bodies kept near freezing temperatures – brighter pink-red In carbon monoxide, hydrocyanic acid poisoning – cherry red In cyanide poisoning – bright red In nitrate poisoning – brown In potassium chlorate, potassium bichromate , nitrobenzene, aniline poisoning – chocolate or coffee brown Intense in the face neck & upper chest of obese persons Dark purple Tardieu spots may appear – in intense lividity COLOUR OF HYPOSTASIS 17

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DIFFERENCES WITH P M S & CONTUSION: 

DIFFERENCES WITH P M S & CONTUSION P M S Cause Rupture of BV & extravasation Engorgement of BV due to pooling Site Anywhere Dependent parts Surface Elevated Not Epidermis May abraded Not Margins Merge with surroundings Clearly defined Histology Signs of inflammation Not Colour Depend on age Mostly purple Incision Blood in cut tissue & cant wash off Blood oozes out & can wash off Enzymatic study Change in level of some enzymes No change Microscopy Blood elements outside the vessel, May evidence of inflammation Blood elements within the blood vessels, No evidence of inflammation CONTUSION P M S 19

INTERNAL LIVIDITY: 

INTERNAL LIVIDITY Lungs are the best organ to demonstrate internal lividity Aspirated blood may settle into the posterior aspects of the lungs if the victim is supine In a hanging victim internal lividity may more pronounced in the most dependent loops of small intestine Visible delineation of lividity in Hanging – tissues below the level of ligature are normal, where as the tissues immediately above the level of ligature may have red-purple suffusion. 20

PowerPoint Presentation: 

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DIFFERENCES WITH P M S & CONGESTION: 

Features Hypostasis Congestion Situation Dependent part of the organ Whole part of the organ affected with the pathology Cause Passive capillovenous distension Due to pathology of organ Swelling Nil May be appreciable Cut surface Oozing of blood from distended vessels Exudation of fluid, mixed with blood Hollow viscus Stomach & intestines when stretched shows alternate stained and unstained areas Shows uniform staining DIFFERENCES WITH P M S & CONGESTION 22

MEDICOLEGAL SIGNIFICANCE OF HYPOSTASIS: 

MEDICOLEGAL SIGNIFICANCE OF HYPOSTASIS Ascertaining whether a body has been moved from the position in which it originally lay when the life ceased Ascertaining the postmortem interval Characteristic distribution may suggest manner of death as in hanging Colour may impart clues towards cause of death A good indicator of occurrence of death 23

REFERENCES: 

REFERENCES David Dolinak , Evan Matshes , Emma Lew. Forensic Pathology, Principles and Practice 1 st ed.2005 Krishan Vij . Textbook of Forensic Medicine & toxicology, Principles & Practice 5 th ed.2011 B. Umadethan . Forensic Medicine. 1 st ed.2011 Jay Dix. Color Atlas of Forensic Pathology.2000 24

Thank You!: 

Thank You! 25