Postmortem Changes Flashcards
What happens for somatic death to occur?
Total diffuse hypoxia.
Cells degenerate as described for hypoxic cell injury.
Define autolysis.
When does it occur?
It is self-digestion or degradation of cells and tissues but the hydrolytic enzymes normally present in tissues.
Occurs after somatic death.
What is putrefaction/decomposition?
Process by which post mortem bacteria break down tissues.
Gives color, texture changes, has production, odors
What type of tissues undergo autolysis first?
Name 5 of them.
Those tissues with greater [C] of proteolytic enzymes will undergo autolysis first.
GIT, pancreas, gall bladder, kidney, liver.
What do the morphological postmortem changes depend upon?
Cause of death, environmental and body temperatures, and microbial flora (herbivores can decompose faster)
Define rigor mortis.
When can it begin?
How long does it persist?
What factors can affect the onset of rigor mortis?
1) It refers to the contraction of the muscles after death.
2) Begins 1-6 hours post death.
3) Can persist 1-2 days
4) High heat and high activity before death as can accelerate the onset of rigor mortis.
Define algor mortis?
What is it dependent upon?
It is the cooling of the body post mortem.
It depends on the T* of the body at time of death
What is liver mortis?
It is the condition where gravity pulls the blood post mortem causing variation in the color of tissues like the skin, lungs, heart, kidney, and liver.
Some areas will be red and the areas where blood was kept away will be pale.
What is another name for liver mortis?
Hypostatic congestion.
When and where does post mortem blood clotting occur?
By what is it influenced?
Occurs several hours after death in the heart and the vessels.
Can be influenced by ante mortem changes in the blood (ex warfarin poisoning, hereditary coagulopathies can cause delay or failure of clotting)
What is responsible for a chicken clot appearance?
The separation of RBCs to the bottom and clotted serum on top
Describe pre mortem clots.
They’re attached to vessel walls (arterial type), loosely attached to vessel walls (venous thrombi), dry and duller (color), are laminated.
Describe post mortem clots
Unattached to vessel walls
Shiny and wet
Perfect cast of vessel lumina
Define Hemoglobin imbibition
It is the red staining of tissues, esp the heart, arteries, and veins
How does hemoglobin imbibition occur?
Hg is released by Lynde RBCs and penetrates the vessel wall and extends into the adjacent tissues
In what other circumstance can hemoglobin staining occur?
It can occur in acute Intravascular hemolysis
Define bile imbibition
It is when bile in the gale bladder starts to penetrate the wall and stains the adjacent tissue yellowish to greenish brown
What is another name for hyperbilirubinemia?
Icterus
What causes bloating?
Postmortem bacterial gas formation in the lumen of the GIT
What is ruminal tympany?
Pre mortem gas distention due to the overgrowth of bacteria or something wrong with the GIT.
Can cause a bloat line
Explain pseudomelanosis.
It refers to the greenish-black discoloration of tissues post mortem.
It is the formation of hydrogen sulfide with iron caused by the decomposition of blood by bacterial action.
It occurs soon after death and can be seen not only in the gut wall but also those tissues in contact with the gut like the kidney, liver, and spleen.
Occurs on the surface as opposed to say, a hemorrhage
