Studied by 3 peoplePostmortem changes
refers to a continuum of changes that occur in a dead body following death
Algor Mortis
Cold Death
First demonstrable change after death is cooling of the body
Not a reliable indicator as to the time of death due to the different temperature of the environment
2 to 2.5 deg F/hr
1st hour
1.5 to 2 deg F/hr
next 12hrs
1 deg F /hr
next 12-18hrs
Rigor Mortis
Rigidity of the body due to hardening of the skeletal muscles caused by a series of physiochemical events after death
formation of locking-chemical bridges between actin & myosin
Lack of ATP regeneration and increased lactic acidity
energy dependent breakage of sarcomere contraction
the glycogen stores are rapidly depleted, preventing ___
Sets within 2 hrs after death
head & neck → small muscles → larger muscles
6-12 hrs
complete and fully fixed
36-48 hours
Dissipates
Anti-gravitational Rigor Mortis
Fixed rigor mortis of the upper extremities wherein the arms are suspended against gravity indicating they were previously held in that position during time of death
Livor Mortis or Postmortem hypostasis
Blood supply gravitates to the skin vessels which become toneless and dilate after circulation ceases
deep purple-red discoloration in the skin
Blanching
occurs in gravity dependent areas of the body that come into contact with firm surfaces
20 min after death
Becomes evident as early as ___
Erythrocyte Sedimentation Rate
rate of settling of red blood cells
within 4 hrs
Fully evident
8 - 12 hrs
fixed
Lividity
Blood settles down in the lowest elevation of the body
pink to purple discoloration
blood pooling in dependent areas of the body
Tardieu Spots
Auguste Ambroise Tardieu
ecchymoses; subpleural spots of ecchymosis that follow the death of a newborn child by strangulation or suffocation
purple to black spots
rupture of capillaries
Tache noir de la sclerotique
After death, the skin and mucosal membranes may desiccate resulting in a change in color and character of these tissues
horizontal linear scleral blackening along the equator of the globe of the eye
sclera is exposed to drying when the eyelids are incompletely shut
initially red in appearance and over time becomes black
Lips, tip of tongue and scrotum darken with postmortem drying
mastoid-to-mastoid incision
scalp
I-incision
straight line incision from chin to pubic symphysis
Y-incision
starts from the acromion and meets at the xiphoid process and continues up to the pubic symphysis
Modified Y-incision
made from suprasternal notch to symphysis then extends over clavicle to its center on both sides and passes upwards over neck and behind the ear
To expose:
chambers of the Heart
inner lungs
inner liver
urinary bladder cavity
GIT lumen
Purposes of Opening Up
Technique of Virchow
organs removed and dissected individually
head → thoracic → abdominal organs
order of examination
Technique of Rokitansky
in-situ dissection in part combined with en bloc-technique
analysis/study on site
Technique of Ghon
en bloc Technique - only get a portion
Technique of Letulle
en masse Technique - complete removal
Needle Autopsy
get a sample using a needle
blind biopsies
Multiple percutaneous needle biopsies after death
Laparoscopic (abdominal) and thoracoscopic (chest)
investigation with tissue sampling
Mini-autopsy
extensive organ sampling or removal via a limited incision
CT and MRI
red vessels, areas with mass, areas with blockage, etc.
3 months after final report
Wet Tissue
10 years
Paraffin blocks, Slides, Reports
3 years
Wet Tissue
indefinitely
Paraffin blocks, Slides, Reports, Gross Photos, Dried Blood stain or frozen tissue for DNA
1 year
Body Fluids & Tissues for Toxicology
Liver: 1500-1800gm
heaviest human organ
Ovary: 5-7gm
lightest human organ
Right atrium
thinnest heart blah
Left ventricle
thickest heart blah
Note
Flashcard