Agonal Period --> Clinical Death --> Brain Death --> Biological Death --> Cellular Death
Progression of Somatic Death
Death is a series of physical and chemical changes.
Death starts before the medico-legal time of death.
Death is a process and not necessarily a specific moment in time.
Death often continues for a very lengthy and protracted period of time.
Death finally arrives at a point of irreversibility; the cessation of all vital life functions.
(nothing more can be done to restore life)
DEFINING DEATH IS DIFFICULT AND CONTROVERSIAL
Agonal refers to the process of death or dying.
It is the period just before somatic death begins.
Before the body loses the ability to sustain physiological and metabolic activity.
- AGONAL PERIOD
- AGONAL STATE
A dying condition, dying, death bound.
A moribund person is in the process of dying.
Doctors use this term.
The respiratory gurgling caused by a loss of the cough reflex and an accumulation of mucous in the throat.
The semi-convulsive twitches that occurs before death.
Death of the entire body.
Death of the organism as a whole.
The inability to sustain physiologic and metabolic activities
Occurs when spontaneous respiration and heat beat cease.
It is one phase of somatic death, lasting for 5 to 6 minutes.
This is the period of time during which life may be restored.
A function of time without oxygen or blood circulation to the brain.
This is the period of time when organs (not tissue) must be harvested for donation.
Is irreversible somatic death
The cessation of simple body processes
The organs of the body do not function
The ante-mortem or post-mortem death of cells.
necrobiosis is the physiological death of the cells- followed by their replacement.
necrobiosis is a good thing and happens every day in a healthy body.
necrobiosis / bio / there is life in this word.
ONE FORM OF ANTE-MORTEM CELLULAR DEATH IS NECROBIOSIS
necrosis is the pathological death of a tissue that is still a part of the living organism
necrosis is a bad thing.
examples of necrosis include decubitus ulcers (DCU), pressure sores, and gangrene.
ANOTHER FORM OF ANTE-MORTEM CELLAR DEATH IS NECROSIS.
It is the process during which individual cells die…it may take hours.
Brain and nervous system 5 minutes
Muscle cells 3 hours
Cornea cells 6 hours
Blood cells 6 hours
POST-MORTEM CELLULAR DEATH FOLLOWS SOMATIC DEATH
The cooling or lowering of the body temperature just prior to death
Often seen in elderly patients, metabolism and circulation is slowed
- TEMPERATURE CHANGES
- AGONAL ALGOR
An increase in body temperature due to febrile issues
Caused by infection, toxemia, or poisoning, this can stimulate microbial growth.
- TEMPERATURE CHANGES
- AGONAL FEVER
An increase in the amount of moisture or fluids in the tissues and body cavities.
Due to disease or agonal capillary expansion.
- MOISTURE CHANGES
- AGONAL EDEMA
A decrease in the amount of moisture or fluids in the tissues and body cavities.
Due to dietary or intestinal problems and febrile issues.
- MOISTURE CHANGES
- AGONAL DEHYDRATION
The movement of micro-organisms from one area of the body to another.
Movement may be caused by:
circulation of the blood
- BACTERIAL TRANSLOCATION
These can be exacerbated by the time between death and embalming.
The embalming process will retard, interrupt, or reverse these changes.
PHYSICAL & CHEMICAL
Do not create chemical changes or chemical by-products.
Brought about by forces of nature:
increased blood viscosity
endogenous invasion of micro-organisms
Things that are caused by factors inside the body.
Things that are caused by factors outside the body.
is the settling of blood or other fluids to dependent areas of the body.
hypo / less than normal stasis / static; lack of movement
Areas where blood movement or gravitation has been inhibited due to contact with the surface upon which the body rests.
A postmortem intravascular discoloration as a result of hypostasis.
The extent of livor mortis depends upon blood volume and blood viscosity.
- LIVOR MORTIS
- CADAVERIC LIVIDITY
- POSTMORTEM LIVIDITY
The loss of water from body tissues and fluids by surface evaporation (air swipe).
Covering the body with a sheet may protect against air currents.
Covering the body in plastic may promote mold and mildew.
Caused by fluids moving into dependent (lower) areas of the body, tissue can become engorged and distended.
The ability of cells to draw moisture from the surrounding areas into themselves
This may case postmortem edema.
Technically not a clot.
The formed elements of the blood stick together causing poor drainage.
Poor drainage will cause formaldehyde gray.
Refers to the thickness of the blood (not clotting of the blood).
Blood cells stick together. Sludge or Agglutination.
INCREASE IN BLOOD VISCOSITY
The colon is the origin of most of the bacteria that cause problems.
Clostridium Prefringins (historically C. Welchi) causes the most problems for embalmers
A gas producing anaerobic bacillis, C. Prefringins will cause tissue gas within 1 or 2 hours.
ENDOGENOUS INVASION OF MICRO-ORGANISMS
A shift in body ph
POSTMORTEM CHEMICAL CHANGES
A rise in body temperature after death.
The continuation of metabolism after death will create heat.
The living body uses perspiration, respiration, and blood circulation to regulate temperature
These processes are not available to the dead human body.
A reddish extravascular discoloration brought about by hemolysis of blood cells.
Hemolysis begins 6 to 10 hours after death. Hemolysis releases hemoglobin.
A single red blood cell contains several million hemoglobin molecules.
The normal pH for a living body is about 7.4 on the scale.
After death the body becomes acidic, about 6.0 on the scale. The body remains acidic during rigor mortis.
After rigor passes and decomposition begins the body becomes alkaline, in the 8.0 or 9.0 range.
SHIFT IN BODY pH
Relaxation of the muscles immediately after death.
When rigor passes naturally from the un-embalmed body.
The postmortem stiffening of the muscles by natural processes.
Rigor results in the muscles inability to re-synthesize adenosine triphosphate (ATP).
Once rigor has passed (or is broken up) it does not reoccur.
“Rigor when it develops involves all the muscles at the same time and at the same rate. However becomes most evident in the smaller muscles.”
Rigor may seem to develop in smaller muscles first; moving to larger muscles last. The eyes, jaw, face, neck…Then the upper extremities, trunk, and lower extremities.
This directional occurrence of rigor from face to feet is
historically known as Nysten’s Law. Named after Pierre Nysten (1744-1817) a French pediatrician.
Once rigor is broken it does not return.
TO BREAK RIGOR MORTIS
Minimum temperature 32 degrees
Ideal or optimum temperature 98 to 100 degrees
Maximum temperature 120 degrees
TEMPERATURE RANGE FOR RIGOR MORTIS
Sudden involuntary movement or convulsion brought about by involuntary muscular contractions.
This may be associated with rigor mortis.