Micro-Scholarship, What it is, How can it help me.pdf
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Chapter 13 - Process of Death
1. The Process of
death
Chapter 13
Forensic Science
Mrs. Morgan
2. Confirming Death
⢠Although it may be obvious,
any death must be confirmed
by a trained professional â
usually a doctor, coroner or
medical examiner
⢠Must meet the criteria of death
â then pronounced dead
⢠Body can then be moved,
handled and processed if
necessary
3. At the crime scene
⢠A dead body found at a crime
scene is handled and processed
by the medical examinerâs office
⢠Officers and CSIs cannot touch
or move the body until the ME
has given permission to do so
⢠Any evidence on a body is
collected by the ME staff and
turned over to the crime lab
4. Time of Death
Algor Mortis: Body cooling
rate
⢠The body slowly cools once the
heart stops beating
⢠Measuring body temperature can
approximate the time of death
⢠Use liver temperature
⢠Can be influenced by the
environment or internal
conditions
5. Click to Time of Death
edit Master title style
⢠Calculating time of death â Glaister Equation
Hours since death = 98.4°F â internal body temperature
1.5
⢠Used as a starting point to determine time of
death â ultimately use other factors to
corroborate a more accurate time
6. Changes to the body
Livor Mortis: skin discoloration
caused by the pooling of blood
⢠When heart stops beating,
blood pools and coagulates
in lower portions of the body
due to gravity â creates
red/purple blotches
⢠Can show the position of
body after death
⢠May indicate if the body has
been moved or repositioned
7. Post-Mortem Lividity
â˘Starts 30 min â 3 hours after death
â˘Maximum lividity 6 â 12 hours after death
Parts of body touching the
ground/surface show no lividity
due to compressed capillaries
8. More changes
Rigor Mortis: rigidity of skeletal
muscles
In humans:
â˘starts after about 3 hours
â˘reaches maximum stiffness
after 12 hours
â˘gradually dissipates until
approximately 72 hours
after death. I donât know â I googled
ârigor mortisâ and this
was one of the top hitsâŚ
9. Overall timetime death
Overall of of death
⢠Pathologists will use multiple factors to
calculate TOD
⢠Always a small margin of error
Temperature of
Stiffness of body Time since death
body
Warm Not stiff Not dead more than 3 hours
Warm Stiff Dead between 3 and 8 hours
Cold Stiff Dead between 8 and 36 hours
Cold Not stiff Dead for more than 36 hours
10. Stages of Decomposition
Initial or fresh decay
(autolysis): The cadaver appears
fresh but is decomposing internally
due to the activities of bacteria
present before death (0-4 days).
Putrefaction or bloating: The
cadaver is swollen by gas produced
internally, accompanied by the
odor of decaying flesh (4â10 days).
11. Stages of
Decomposition
Black putrefaction: Flesh of
creamy consistency, with exposed
body parts black. Body collapses as
gases escape. Fluids drain. Odor of
decay very strong (10â20 days).
Butyric fermentation: Cadaver
drying out. Some flesh remains at
first; cheesy odor from butyric acid
(20â50 days).
12. Stages of Decomposition
Dry decay (diagenesis):
Cadaver almost dry; slow rate of
decay. May mummify (50â365
days).
All of the changes that accompany
decomposition are subject to
variation based on individual
characteristics and the environment
13. The autopsy
⢠Performed to determine
cause and manner of death,
discover the extent of disease
or for teaching purposes
⢠Forensic autopsies have legal
implications
⢠Performed by a pathologist â
specially trained MD
14. Who & why
⢠ME can order an autopsy
⢠If not â need permission from next
of kin
⢠Autopsied people include
â Suspicious deaths
â Not under the care of a doctor
â Died during an operation
⢠Family can limit scope or request
specific procedures be followed
15. The tools
Stryker saw â used to cut
through the skull to
remove the brain
Standard tools used in
an autopsy
16. Autopsies â the outside
⢠Starts with thorough external
exam
â Physical attributes
â Scars and/or tattoos
â Evidence of wounds/bruises
â All findings diagramed and
recorded in detail
17. Autopsies â the inside
⢠Body is open with a Y-incision
to expose the thoracic and
abdominal cavities
â Shoulders to pubic bone
⢠Ribs are cut to expose the heart
and lungs
⢠Organs are removed, weighed
and examined
18. Finishing up
Tissue and fluid samples are
taken, analyzed and stored
Organs returned to proper
place in cavities and
incisions are sewn up