thanatos- death; logos- science Assoc. Prof. Beatrice Ioan MD, PhD, MA THANATOLOGY thanatos- death; logos- science Assoc. Prof. Beatrice Ioan MD, PhD, MA

Death Irreversible loss of the properties of the living matter. Cessation of life in a previously viable organism Process - different rates of cellular death - internal organs have different functions with different cellular metabolic processes which cease to function at different rates

Stages of death 1. Agony (vita minima) irreversible stage between life and death mixture of vital and thanatologic processes Decreased activity of cortical neurons Bulbar centers are no longer controlled by cortical and sub-cortical centers- functioning of the organism is no longer unitary

Agony Progressive disappearance of psychical functions- psychical chaos Decreased contact with the environment Complete immobility Progressive disappearance of senses Diminished vegetative functions

Agony Classification I. According to duration: absence of agony- death occurs very rapidly short agony (seconds, minutes) long agony (hours) II. According to the psychical condition: conscious agony- no changes of consciousness; unconscious agony; alternation of conscious and delirious periods Importance: Validity of the documents signed during agony

Stages of death 2. Clinical death Short interval (about 5-10 minutes) Cardiac activity and respiration are absent Cortical neurons still function The patient can be reanimated by medical means 3. False death Very diminished respiration and heart activity Cannot be detected by ordinary means Loss of consciousness

Stages of death 4. Biological death (real death) irreversible characterized by cessation of cellular metabolism and structural changes of cells Stages: Somatic (systemic) death complete and irreversible cessation of vital functions life ceases in the body but still persists in some of its parts b. Molecular (cellular) death death of the tissues and cells individually due to anoxia- different tissues die at different rates

Signs Of Death I. Diagnosis of death in clinics- immediate signs of death - Cerebral death - Absence of cardiac activity and circulation - Absence of respiration Diagnosis of death in the autopsy room II. Early signs of death - Postmortem lividity (hypostasis) - Rigor mortis - Cooling - Dehydration - Autolysis III. Late signs of death - Putrefaction (postmortem decomposition) - Conservatory processes

Postmortem lividity (hypostasis) Mechanism the circulation ceases ↓ accumulation and stagnation of blood in the capillaries and small veins of the skin and organs the blood is pulled by gravity in the lowest areas of the body Aspect discoloration of the skin in lowest parts of the body red-bluish/ compression areas

Postmortem lividity (hypostasis) Stages: Hypostasis- 10-12 hours Stasis- 18-20 hours Imbibition- after 20-24 hours Differentiation of the postmortem lividity from bruise Forensic relevance Diagnosis of death Position of the body Postmortem interval Cause of death

Rigor mortis (cadaveric rigidity) Mechanism Decrease/ disappearance of ATP in the muscles - ATP concentration fails to 85 per cent of normal Factors affecting the timing of rigor mortis - temperature of the environment - physical activity before death - cause of death Stages- Nisten rule Installation- 3-6 hours Generalization- 24 hours Disappearance- 24-36 hours Forensic importance Diagnosis of death Position of the body Postmortem interval Cause of death

Postmortem cooling (Algor mortis) Mechanism - Failure of heat production and thermo-regulation → the body is loosing heat (conduction, convection, radiation) → temperature of the body decreases progressively → equilibrium with the environmental temperature Factors affecting postmortem cooling Environmental temperature Air moving and humidity Clothing and coverings Posture Surroundings Dimensions of the body Hemorrhage Particular: postmortem caloricity 18 degrees Celsius - 1 degree Celsius per hour Forensic importance- diagnosis of death, postmortem interval

Dehydration Mechanism Cessation of circulation and metabolic processes → the body looses water Aspects - pergamentation - finger pads’ skin and lips-wrinkled - opaque cornea - soft eyes

Autolysis auto- self; lysis- destruction enzymes released from the cells soften and liquefy the tissues of the body internal examination organs with a high content of enzymes (e.g. pancreas, stomach) prepares the field for putrefaction can be prevented by freezing the body/tissues

Putrefaction (postmortem decomposition) The last stage in the resolution of the body from organic to inorganic state → skeleton Bacterial process Factors affecting putrefaction - environmental temperature - concentration of oxygen - concentration of water (brain) - age- old age cause of death

Putrefaction (postmortem decomposition) Aspects green spot of putrefaction- 2-3 days all the skin - dark green or almost black gases of putrefaction- increased volume marbling Particular situation * New born

Forensic entomology Study of the insects that infest the corpses Flies lay their eggs on the corpse- opened wounds and moist sheltered natural orifices- 18/36 hours (high temperature) Maggots or larvae - 24 hours -inside the body- destroy soft tissues Pupae - 4-5 days Adult flies - 3-5 days 7 series - 3 months→ 3-4 years One species at one time on one body fragment- different nutrients

Conservatory processes Natural processes which, prevent putrefaction and preserve the corpses Mummification Very rapid dehydration - warm climate + good ventilation - Bacterial activity stops- high temperature - 3-12 months after death Aspect Skin- dry, shrunken, leathery, brown to dark skin adhering closely to the bones Odorless Preserved features Reduced body volume Internal organs - dried mass

Conservatory processes II. Saponification (Adipocere) - Fatty tissues are hydrolyzed - saturated fatty acids (stearic, palmitic acids) → calcium soaps 3-12 months Aspect yellowish- white greasy wax like substance rancid smell - floats on water - can be easily cut burns - yellow flame Factors affecting saponification Environment- moisture; warm temperature; absence of air Lecithinase from Clostridium Welchii

Conservatory processes III. Lignification Environment with great concentration of tanic and humic acid (swamps, mines, volcanic lava) Aspect brownish, hard skin soft bones (loosing of calcium); good preservation for a long interval Tolund Man- Denmark

Conservatory processes IV. Refrigeration Exposure of the corpse to low temperature Aspect whole body is stiffen; perfect preservation for a long period of time; when the body is bring into an warm environment putrefaction develops rapidly

Forensic Autopsy Mandatory in the following situations (Criminal Law): Violent death Sudden death Suspect death Medical malpractice allegation Corpses with unknown identity Rules: performed in the base of the order of juridical authority complete