Forensic Medicine Flashcards Preview

PBDII Test I > Forensic Medicine > Flashcards

Flashcards in Forensic Medicine Deck (33)
Loading flashcards...
1

what is the major focus of a forensic investigation

why did someone die? cause of death
how did they die? mechanism
what is the manner of death (NASHU)
Natural
Accident
Suicide
Homicide
Undetermined

2

who can legally certify and sign a death certificate?

physician can only sign if the death was natural

all others are medical examiners
-accident
suicide
homicide
undetermined

3

major misconceptions

time of death
-not something that can be established in a limited time frame
-rigor mortis- reaches peak at room temp at 24 hours


rapidity of testing
-diagnostic tests take longer times




4

The focus of a forensic examination/inquiry is not natural death (other than to rule out/discern evidence for, or consider circumstances which may be indicative of foul play)

medical examiners have no duty to the family but to the state

if a family is exceptionally against an autopsy, then be suspicious b/c family members are more likely to be involved in the crime

family can be a problem

5

why are there so few autopsies done at hospitals

b/c of lawsuits

so they are performed at ME offices --> but the focus is never on natural death

6

what is the wounding formula

W = E x 1/T x 1/A x K

K = modifying factors (elasticity of the striking object or the tissue being injured etc)

E = Energy transferred = ½ MV^2

T = Period of energy transfer (time)

A = Area of application of force

inversely related to time and area

7

the more young men b/w 15-34, the more violent the crime

testosterone makes you crazy

8

physical environment injuries

mechanical force
-laceration is ALWAYs due to blunt force injury, split of tissue
-abrasion
-contusions
-incise wounds
-gunshot wounds

thermal injuries
-burns
-hypothermia
-hyperthermia

ionizing radiation
-leukemia and lymphomas initated

electrical injuries

atmospheric pressure
-blast injury
-decompression

9

cause of death versus mechanism of death

mechanism:
shock
cardiac arrhythmia/arrest
septic shock

cause of death:
AIDS

10

manner of death examples

natural
accident
suicide
homicide
undetermined

11

three typical wounds produced by blunt force trauma

abrasion
contusion
laceration

12

laceration

soft tissue bridging
depths


13

contusion
extent and severity depends on

amount of force

vascularity of tissue injuried

type of tissue (areolar tissue such as eyelids, bleeds more)

location of the tissue-->
tissue over bones is more easily bruised

easily bruisability - advanced age, cirrhosis, coagulopathies

14

contusions and color?
yellow
blue, purple
brown

yellow- most significant color and its presence indicates that the bruise is at 18 hours or older

blue, purple and red do NOT assist in dating bruises

brown is a mixture of colors and therefore is not useful

15

abrasion

epidermis is injured by friction/scraping or crushing

oozes serum or blood, but does not bleed profusely

torsional marks
rolled edges of skin tell directionality

16

3 types of abrasions

brush- grazing or sliding motion.

impact

patterned- recapitulates the surface appearance of the instrument

passenger windows cause dicing injuries

wheres windshield glass causes other marks

17

stab wound

sharp force injury in which the depth of the wound track is greater than the length of the wound on the skin (deeper than longer)

18

single blade edge

sort of triangle with one edge that isn't "sliced" like the other edges

19

gun shot wound against skin
close range 1-2 inches

marginal abrasion

stippling deposited (debris) = intermediate gunshot wound

medical examiners can measure what the range/distance from skin was

wad inside a shotgun shell - shows up as a small round circle

pellets

20

shotgun wound on the head

the adult skull has an inner outer table separated by the diploe

in entry wound the outer table of the skull is typically sharply circumscribed and the inner table is beveled

fracture emanating from blunt force or in some cases gunshot wounds, do not ramify across previous fracture lines (don't cross)

21

mass disasters approach

macro level: the scene
-safeguarding- live people first
-surveying
-documenting
-proper approach to specimen retrieval

Micro level:
biologic materials retrieval and transmittal vs. inorganic specimens/substances

22

37 year old male
uresponsive
no singinficant PMH
diuretic for high blood pressure
50 lb overweight
smoker
hasn't seen physician in 3 years
trauma to his face

looks like shit - looks like there are bumps/bruises and abrasions on the body that are consistent with a fall/trauma

what is the plan of action...

he does have an elevated serum glucose
what is the most likely cause, mechanism and manner of death?

send the body to the ME b/c it looks like there is trauma to the body
he is not being followed by a physician and doesn't really have a diagnosis


he does have risk factors for sudden cardiac arrest:
high blood pressure
obese
smoker

he has lacerations/abrasions over the bony prominences and no other types of trauma

atherosclerotic cardiovascular disease natural death

23

patient
drinking bac of .2
black out and head hurts
laceration on the back of his head
being annoying

laceration on the back of his head

based on the appearance of the wound (scalp lac) you conclude...

the lesion is NOT a sharp force injury. He likely fell due to inebriation

the injury is due to blunt force (could be the ground)

soft tissue bridges*** true laceration due to blunt force trauma, may bleed significantly
marginal abrasion

unless it is a very severe injury, the patient doesn't necessarily need MRI/CT

24

patient with gunshot wounds of his chest two entries on the left and single exit on the right
bilateral hemothorax

the exit is much larger than the entry, what does this imply...

he also shows powder stippling of the shoulder what does this imply...

the feature imply a homicide attempt

exit wound--> this implies high velocity--> much more related to the speed of the projectile than the mass

stippling means it was an intermediate gunshot wound and most likely NOT self inflicted

25

middle aged white male hanging from a noose

rigor mortis and livor mortis of his extremities

tardieu spots
wearing high heeled shoes, hosiery and panties
body is surrounded by angled mirrors and various large picture of naked women

gas-mask type of apparent military equipment on his face

what should you conclude...

autoerotic asyphxia

this is an accidental death

26

3 types of decompisition

putrefactive
-own endogenous flora will go through bowel wall, green patch in the lower abdomen
body is degraded by own bacteria, then secondary bacteria, then insects/magots

adipocere formation
-skin degrades, fat saponification

mummification

27

livor mortis

blood goes to dependent areas

so if they die on their back then blood goes to the back

becomes fixed

can help you tell if a body has been moved

28

those that are burned significantly and survive suffer from what infection

pseudomonis aeruginosa

29

the us homicide rate is....

males 15-34

30

27 year old male
gunshot wound right temple
round marginal abrsaion and powder stiplling around the wound
no gunshot powder residue in the depths of the wound

gunshot wound of injury
intermediate range

implies homicide

31

what is the best method for blunt force injury to the head

an iron rod

32

what case would you send to a qualified pathologist

22 year old man found in the woods and decomposing

72 year old dies after long hospitalization for pancreatic carcinoma. Cause of death is pancreatic carcinoma

elderly man with atherosclerosis and poorly controlled diabetes dead in his home

33

a medical examiner/pathologist is responsible for...

determining the cause and manner of death of cases falling within his/her jurisdiction

don't work for the police
dont' work for the families
they work for the public