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Changes After Death. Dr. Raid Jastania. Changes After Death. Decomposition Why do we need to know: Not to misinterpret these changes Help to determine time (place) of death. Early Changes. No breathing, no circulation Fall in blood pressure Metabolism gradually stops
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Changes After Death Dr. Raid Jastania
Changes After Death • Decomposition • Why do we need to know: • Not to misinterpret these changes • Help to determine time (place) of death
Early Changes • No breathing, no circulation • Fall in blood pressure • Metabolism gradually stops • Loss of neoronal activity • No reflexes, no corneal reflex, fixed dilated pupils, eye looses the tension
Early Changes • Primary Flaccidity: complete loss of tone • Muscle may be still reactive for hours (focal twitching) • Pale skin and conjunctiva • Face may remain blue/red • ?? Hair continues to grow • Loss of sphincter action: pass urine, semen, regurgitation of food
Rigor Mortis • Lack of oxygen – no energy – no ATP – glycolysis – lactic acid – acidic cytoplasm – actin and myocin bind • “Stiff Muscle” • Factors affects Rigor Mortis: • Level of glycogen • Level of lactic acid • Body built • Temperature, weather
Rigor Mortis • What is Rigor mortis like if death occurs after • exercise, • electric shock, • in infant, • in elderly • In summer • In winter
Rigor Mortis • Starts in small muscle around eyes and mouth, jaw, fingers, • Then spreads from head to legs • Estimated time of death: • In face: 1-4 hours • Limbs: 4-6 hours • Increase in strength for the next 6-12 hours • Decomposition starts • Secondary flaccidity from 24-50 hours
Rigor Mortis • Body feels warm & Flaccid: <3 hours • Body feels warm & Stiff: 3-8 hours • Body feels cold & stiff: 8-36 hours • Body feels cold & flaccid: > 36 hours
Cadaveric Rigidity • Forensic rarity • Stiffness of muscle occurring immediately at time of death • Finding items in hands • ?emotional/physical stress at death
Post Mortem Hypostasis (Lividity) • No circulation, relaxation of blood vessels • Blood moves to dependent area • Positioning of body: supine, prone, on side, on head, hanging • Pink-blue color of the dependent area • May not be apparent in infants, elderly, anemic • Difficult to see in dark skin, jaundice
Post Mortem Hypostasis (Lividity) • Blanching: • Around face (not asphyxia) • Color: • Pink – deep pink – blue – purple • Cheery pink: in carbon monoxide poisoning • Dark red: in cyanide poisoning • In hypothermia: pink around large joints • Movement of body and change in lividity!
Cooling of the body after Death • Physical property • Assumptions: • Temperature was 37 at the time of death • Thermally static environment
Cooling of the body after Death • Variables: • Mass of body • Surface area • Body temperature at death • Site of reading • Posture • Clothing • Environment temperature • Winds, humidity, rain
Estimation of the time of Death • Body temperature • Rectal, ears, nose, liver • Henssge’s Nomogram • Body temperature • Ambient temperature • Body weight • Other methods • Gastric contents • Entomologist • Anthropologist
Decomposition • Air • Dry, wet • Water
Putrefaction • The most common route of decomposition • Liquifaction of the soft tissue over time • The warmer the temperature, the earlier the process
Putrefaction • Visible 3-4 days • Green discoloration in the right iliac fossa • Marbling of skin: linear branching ptterns of brown discoloration of skin • Blistering, skin sloughs off • Gas formation, swelling of body: face, abdomen, breast, genitalia
Putrefaction • Increase internal pressure, protrusion of tongue, eyes, • Bloody fluids • Within a week: body cavity will burst • Tissue liquify
Mummification • Dry condition, eg. Dessert • Drying and leathery body • Part or whole body
Adipocere • Wet condition, water • Chemical change of body fat to waxy compound material • Pale, greasy semi fluid material, unpleasant smell • Firm waxy compound material: takes weeks to months to form
Skeletalization • More quickly to occur on the surface than in burried body • Soft tissue will be absent by 2 years • Tendon, ligaments, hair nails may remain • By 5 years bone disarticulate
Identification • Living: coma, amnesia, infancy, mental defect • Decomposed body • Following injury • Mass disasters
Appearance Height, weight Hair color, length Beard, moustache Skin pigmentation Ethnic background Eye color Clothing, jewellery Tatoo, surgical scars Injuries, deformities Age: Estimation Ossification center General Morphologic Features
Fingerprint • Chance of identical finger print is: 1 in 64 million • Identical twins
Teeth • Identification of person • Age • Bite marks
Identification of origin of tissue • Why: • Blood, semen, saliva.. • Come from suspect for victem • Match of human remains • Resolve paternity/maternity
Identification of origin of tissue • DNA profiling: • Matching • Paternity, maternity • Sampling: • Nucleated cells: wbc, hair root bulb cells, sperms, buccal smear..
Identification of origin of tissue • Human Remains • Are they human • Is it one or more bodies • Sex: skull, pelvis • Age • Up to 20-25 years, age can be estimated within couple of years • >25 years more difficult to estimate