Intrinsic and Extrinsic Factors Governing Decomposition Flashcards
(35 cards)
- Age
- Sex
- Corpulence
- Cause and manner of death
- Bacterial and parasitic activity
- Pharmaceutical agents
Intrinsic Factors
- Air
- Moisture
- Temperature
- Bacterial and parasitic activity
- Pressure due to earth or clothing
- Vermin including maggots, lice, and rats
Extrinsic Factors
Decompose very slowly because of the absence of intestinal flora.
Age: Stillborn Infants (Intrinsic)
Which have lived long enough to be fed or have breathed will decompose rapidly because of an abundance of intestinal flora.
Age: Infants (Intrinsic)
Because of a lack of mositure and dehydration, will generally decompose at a much slower rate.
Age: An Aged Person (Intrinsic)
So called healthy individual with a high moisture content and high quantity of bacteria in the gastro-intestinal tract, will usually decompose rapidly.
Age: A Middle Aged Person (Intrinsic)
Certain diseases and conditions common to one sex or the other may have a marked influence on the rate of putrefaction.
Sex (Intrinsic)
A higher moisture content and greater amount of subcutaneous fat usually brings on putrefaction at a much greater rate.
Sex: Female (Intrinsic)
Postpartum hemorrhage, death in childbirth, may also caused a rapid onset of putrefaction.
Sex: Female (Intrinsic)
Obese persons decompose more rapidly than thin ones largely because of the higher moisture content and the greater retention of body heat.
- After Death, postmortem caloricity encourages putrefaction.
Corpulence (state of nutrition)
(Intrinsic)
Moisture is essential for bacterial growth. Putrefaction is accelerated when the tissues are edematous, as in death from congestive heart failure.
- Putrefaction is delayed when the tissues are dehydrated as in death preceded by severe vomiting and diarrhea.
Corpulence: State of hydration of the tissues (Intrinsic)
Optimum temperature for the growth of bacteria causing decomposition is 100oF. Postmortem caloricity encourages putrefaction.
- A rapid onset of algor mortis however, will slow down the putrefactive process.
Corpulence: Body Heat (Intrinsic)
Can either increase or alter the rate of putrefaction.
- Example: Any emaciation producing disease causing dehydration, such as febrile diseases, will retard putrefaction.
Cause and Manner of Death (Intrinsic)
The amount of organisms accumulated within the body (especially the intestinal tract, body tissues, and fluids as a result of infection) will hasten the putrefactive process, particularly if the count is high at the time of death. (septic conditions)
Bacterial and Parasitic Activity: Anaerobic Bacteria (Intrinsic)
The decomposition is primarily due to the enzymes produced by the bacteria.
Bacterial and Parasitic Activity: Parasitic Activity (Intrinsic)
A rather recent problem; certain drugs taken prior to death can either hasten or retard putrefaction.
- Example: Coagulants and anti-coagulants, cancer drugs (radium, cobalt), narcotics.
- Anticoagulants can cause postmortem stain
Pharmaceutical Agents (Drugs)
(Intrinsic)
A free access of this accelerates decomposition for two reasons:
- Additional airborne bacteria are carried to the body and could enter through various openings, wounds, etc.
- Decay would be rapid because the organisms would be aerobic.
Air (Extrinsic)
Johann Ludwig Casper, Berlin, Germany.
- All things being equal
- A body will decompose as much in one week lying on the ground as it would in two weeks submerged in water, and as much as in eight weeks buried in the ground.
- A body, then, will decompose at a rate of 1-2-8 in air, water, and underground.
Casper’s Dictum
More pressure means this.
Less Decomposition
Less pressure means this.
More Decomposition
The humidity in the atmosphere. Decay is accelerated when there is a free access to warm, humid air or in a high moisture environment.
- In a hot, dry climate the body will dehydrate rapidly and mummify; bacteria will burn up.
Moisture (Extrinsic)
One of the most important factors affecting bacterial growth.
- Optimum- 98oF - 100oF
- Minimum- 32oF
- Maximum- 120oF (which stops most decomposition)
Temperature (Extrinsic)
The aerobic organisms invade the body and cause decay.
Bacterial and Parasitic Activity: Aerobic Bacteria (Extrinsic)
Free access to air, airborne.
- Enzymes of aerobic bacteria act on tissue as a form of this kind of activity.
Bacterial and Parasitic Activity: Parasitic Activity (Extrinsic)