Death

1. Death Meaning, manner, mechanism, cause and time

2. How do we define Death? Is a person with a heartbeat alive even if there is no brain activity? Death is a process not an event Physiologists; when the heart stops beating, the cells begin to die O2 levels drop Basic processes of the body fails Nerves, muscles, organs stop working, Stoppage Once enough cellular death occurs life cannot restart

3. Forensic Pathologist Examination of the deceased, Autopsy Investigations normally are called upon when the death is: Sudden violent unexplained deaths Investigators will look into Manner Cause And mechanism of death Questions sought to answer: Who is the victim What injuries are present When did the injuries occur Why and how were the injuries produced

5. Forensic Pathology • Autopsy performed to establish cause of death. • Classifications of the manner of Death *Natural *Accident *Suicide *Homicide *Undetermined

6. Manner of Death Five ways people die Natural Interruption and failure of bodily function resulting from age or disease Accidental Unplanned event Suicidal A person purposely kills oneself Homicidal Death of one person caused by another Undetermined Suicidal or accidental Pills, guns

7. Identify what is the Manner of Death? Why? Case 1: A man with a heart condition is attacked and dies from a heart attack during the assault. Case 2: An elderly woman dies after being kept from receiving proper health care by her son.

8. Time of Death

9. Estimating Time of Death • Rigor mortis • Livor mortis: (Lividity) • Algor mortis: Body Core Temperature • Potassium levels in vitreous humor + Clouding of the cornea • Stomach Contents • Evidence of Decompositional Process • Presence/absence of purge fluids • Drying of the tissue • Insect Larval Instars

10. Algor Mortis Uses body temperature to determine time of death Normal body temperature is 370C (98.60F) A body loses heat at a rate of 1.40C per hour until the ambient temperature is reached Rate varies according to environmental temperature Once ambient temperature is reached, you cannot use this method to determine time of death

11. Question: What are some Factors that would affect Algor Mortis? Ambient temperature Wind? Excess body fat? Clothing

12. Rigor mortis: • The medical condition that occurs after death • Results in the shortening of muscle tissue and thestiffening of body parts • Body stays in the position they are in when death occurs • Begins within 12 hours and ends after 48 hours • After 48 hours, muscle cells begin to autolyse

13. Rigor Mortis

14. What are some factors affecting Rigor mortis ? • Ambient temperature, • Cooler the body the slower the onset of rigor • Person’s weight • Fat stores more oxygen and slow rigor • Type of clothing • Helps keep the body warm • Illness • Dies with a fever? What would you expect? • Hypothermic? What would you expect? • Level of physical activity • Struggling before death rigor, What would you expect? • Sun exposure, • Sun tanner? What would you expect?

15. Estimating Time of Death • Rigor mortis • Livor mortis: (Lividity) • Algor mortis: Body Core Temperature • Potassium levels in vitreous humor + Clouding of the cornea • Stomach Contents • Evidence of Decompositional Process • Presence/absence of purge fluids • Drying of the tissue • Insect Larval Instars

16. Livor mortis * Is a settling of the blood in the lower portion of the body ** Causing a purplish red discoloration of the skin. *** Discoloration does not occur in the areas of the body that are in contact with the ground or another object,

17. 3. Livor mortis

18. Autopsy and time of death cont… Livor mortis: the medical condition thatoccurs after death and results in the settlingof blood in areas of the body closest to theground • Evident 30-120 minutes postmortem • 8-12 hours (24-36 hours in cooler temps) postmortem- maximum color or “fixed” livor mortis due to hemolysis (blood vessels break down) • May occur antemortem (before death) in slow deaths • Can congest internal organs

19. Estimating Time of Death • Rigor mortis • Livor mortis: (Lividity) • Algor mortis: Body Core Temperature • Potassium levels in vitreous humor + Clouding of the cornea • Stomach Contents • Evidence of Decompositional Process • Presence/absence of purge fluids • Drying of the tissue • Insect Larval Instars

20. Potassium levels in vitreous humor + Clouding of the cornea Cornea is the clear covering of your eyes Becomes cloudy and opaque after death Takes only a few hours after death if eyes are open at death It takes 24 hours if eyes are closed at death. Cornea

21. Potassium levels in vitreous humor + Clouding of the cornea Vitreous humor is the jelly like fluid found in the eye. Concentration of potassium increases slowly during first few days Vitreous humor

22. 5. Stomach Contents

23. Stages of Decomposition Initial decay Corpse appears normal, internal bacterial decay and autolysis begins Putrefaction Odor of decaying corpse swollen Black Putrefaction Very strong odor, flesh appears black, gases escape, corpse collapses Dry Decay Corpse is almost dry, further decay slows from lack of moisture

24. Stages of Decomposition 2 days Cells autolysis Greenish purple staining occurs, blood decomposing Skin takes on Marbled Appearance 4 days Skin blisters Abdomen swells with carbon dioxide Due to bacteria in intestines 6-10 days Corpse bloats with CO2 Corpse eventually bursts Fluid begins leaking from openings as cell membranes rupture Eyeballs liquefy Skin sloughs off