Forensic Pathology Flashcards
where do most bugs harbor in decomposition bodies?
body orifices, especially the eyes
localizations on the body –> they want to get onto the interior –> so bullet wound and tract.
Mortis:
what are the three different types of mortis?
rigor mortis –> body is stiff due to cross linking of skeletal muscle fibers.. can proceed at a fairly uniform rate (starts a few hours after death and maximum 24-48 hours and then) –> called secondary flaccidity
algor mortis –> cooling of body after death (usually dependent on temperature)…
livor mortis –> no systemic circulation, all RBC and formed elements go to deep ended portions of the body. they become fixed or unfixed
fixed - not blanchable, fixed in place
unfixed - blanchable
all this is kind of meaningless without knowing the baseline temperature
Putrefactive?
adipocere formation
mummification
most common type –> body that has died in a setting in temperate and humid. reduces the body to gas and water. (skin begins to slip, color changes, smells) –> where does it accumulate most? Cecum and the overlying patch of skin (because that’s where most bacteria is located)
body is found in water –> epidermis is dissolved.. lipid layer encasing the body especially in freshwater. preservation aspect.
rare in the US.. but bodies that have died in super arid, low moisture, where there is very few organisms and the body dries up.
major focus of a forensic investigation? 3 things
what is the manner of death mnemonic?
why did they die, how did they die,
manner of death (NASHU) –> natural, accident, suicide, homicide, undetermined
who can legally certify and sign a death certificate for a natural death?
licensed physician, coroner, justices of peace or someone that is allowed by statute to sign one in the absence of a licensed physician
who can sign the death certificate of accident, suicide, homicide, and undetermined deaths?
medical examiner
misconceptions of forensic pathology
time of death –> very hard to determine
rapidity of testing –> takes forever
Databases and facial recognition stuff
role of medical examiner
assign a cause of death (COD) –> scientific
render an opinion as to the manner of death (judicial opinion pretty much.. medical examiner is acting like a drug) –> rests on everything on the case, not just the autopsy.
who does the Medical Examiner work for? what’s super important to know?
NO DUTY to families, so who does he/she work for?
works for society, not family
focus of forensics?
foul play and unnatural death is the focus of forensics
why are there so few hospital autopsies in modern era?
1) everybody gets sued –> something that contributed to the death that you didn’t diagnose earlier by a pathologist but then is found by a forensic pathologist constitutes a lawsuit.
2) expensive and takes time
Medical examiners conduct their autopsies how? why are they done here?
ME have soveriegn immunity –> can’t be sued in the legitimate exercise of their office.
so mostly conducted at ME offices
what role does the family play in decision-making, in terms of when and if an autopsy is performed
no duty to families, so we use our best judgment.
early effects of radiation injury?
blood and bone marrow + gonadal effects on testes and ovaries.
when is homicide the highest?
usually by whom?
15-34, males
what do we want on the death certificate? in order
(immediate) cause of death –> mechanism –> final pathophysiological death
DUE TO
then (proximate) cause of death –> whatever led to the mechanism
manner of death (opinion)
is cardiorespiratory arrest ever a legitimate COD?
no.
this means heart and lung stopped… NO
SIDS, what’s the manner of death?
Lobar Pneumonia?
Natural death –> “not due to foul play”
also natural death –> not due to foul play
homicide is not
it is NOT SYNONYMOUS WITH MURDER.
so lethal injection is homicide
laceration
abrasion, contusion,
laceration –> always due to BLUNT FORCE, not due to a sharp instrument (overcomes the tensile strength and the skin splits)
contusion –> bruise and results from hemorrhage into tissue. the soft tissue is intact –> commony seen in areolar (thin or loss) tissues such as the eyes –> bony surfaces are more vulnerable –> easy bruisability in advanced age, coagulopathy, cirrhosis
abrasion –> epidermis is scraped away or crushed by direct pressure or blow tangential to the surface.
Wounding formula
E x 1/T x 1/A x K
inverse relationship to time and area
if you swing a 2x4, it’ll cause less of an injury pattern than a smaller object with less of a surface. if you swing it more quickly, there’s more wounding.
age of a contusion: what’s the most significant color?
what about the other colors?
brown?
yellow is the most significant color and it’s present at 18 hours or older.
blue, purple, and red DO NOT ASSIST IN DATING bruises
brown is a mix and is not useful.
3 types of abrasions?
brush (gliding) –> motorcycle deaths –> body tumbling on concrete –> grinds it down almost to bone.
impact
Patterned abrasions (surface of a tire or something shows on the abrasion)
Abrasions on the boney prominences is usually telling you what?
a fall. the recesses are
dicing injuries?
driver window fragments and you can see the dicing on the left side of the face –> driver side.
Stab wound: what kind of wound is this called?
what may appear as a small caliber firearm or shotgun pellet wound?
incised wounds, NOT lacerations
icepick?
most civilian
double edge blades –> more miltiary –> oval type
single edge (most civilian) –> triangular
most civilian
double edge blades –> more miltiary –> oval type
single edge (most civilian) –> triangular
salient wounding formula for guns/proectiles?
what’s the most important factor?
KE = 1/2mv^2
velocity…
hollow point, when strikes tissues, does what?
mushrooms over the base.
police use it because it wouldn’t go through the person and hit someone else.
what gun is more likely to have a higher velocity?
long gun has more wounding capability –> accelerating bullet along the barrel
lands and groove pattern rotates the bullet to help it with accuracy
so much more velocity.
contact range
intermediate
distant range
marginal abrasion; soot powder in depths.. no stippling.
marginal abrasion, powder tattooing/stippling around wound
no soot/powder in depths of wound, no powder tattooing/stippling, marginal abrasion
GSW of the head:
GS wounds hit the external table (compact bone) sharp entry–> moves through adult skull, it blows through the inner table (compact bone) –> beveling on the interior.
opposite if it’s going the other way
entry and exit:
low velocity
high velocity
small entry, no exit
small entry, big exit
