Postmortem Changes: Factors Influencing Decomposition

Posted on Jan 13, 2025 in Biology

Constitutional and Pathological Influences on Postmortem Changes

Constitutional Factors

*Physical Constitution*

Obese individuals decompose faster than lean individuals.

*Age*

Putrefaction is more rapid in children and slower in the elderly, with adults experiencing an intermediate rate.

Pathological Influences

The evolution of putrefaction can be accelerated or delayed depending on pre-existing pathological conditions. Generally, the intensity of putrefaction correlates with its onset.

*Conditions Accelerating Putrefaction*

  • **Serious injuries, extensive bruising:** These provide abundant entry points for bacteria.
  • **Septic diseases:** These involve a high bacterial load.
  • **Slow agonies:** These can increase the spread of germs.
  • **Other causes of death:** Asphyxiation, heat stroke, and lightning strikes can also result in intense putrefaction.

*Conditions Slowing Putrefaction*

  • **Major bleeding:** This reduces the bacterial culture medium and limits germ dissemination.
  • **Intoxication by carbon monoxide, hydrogen cyanide, and arsenic:** These substances can inhibit bacterial growth.
  • **Diseases causing severe dehydration:** Dehydration limits the environment suitable for bacterial growth.
  • **High-dose antibiotic treatment before death:** This significantly reduces bacterial flora.
  • **Separated limbs:** These decompose slower than the main trunk.

Environmental Influences

Humidity, temperature, and ventilation significantly impact the development of putrefaction. Under equal temperature conditions:

  • *1 week of putrefaction in the air is equivalent to 2 weeks in water and 8 weeks in the ground.*
  • **Drying and aeration:** Can lead to mummification.
  • **Abundant moisture:** Can lead to saponification.
  • **High heat and intense cold:** Can preserve the body for extended periods.

The Greenish Postmortem Stain

Typically, a greenish stain appears on the abdomen, starting in the right lower quadrant. Initially small and light green or slightly bluish, it intensifies and spreads peripherally. It usually appears 24 to 48 hours after death, with extremes ranging from 14 hours to 5 days. Within 3 to 15 days, the stain spreads throughout the abdomen and other body parts. This stain is caused by the action of hydrogen sulfide, produced during tissue putrefaction, on blood hemoglobin in the presence of oxygen, forming sulfhemoglobin, which appears greenish in air.

Variations of the Greenish Stain

*Topographical Variations*

  • **Death by drowning:** The stain starts in the upper chest and neck due to bacterial penetration through the airways.
  • **Deaths with cephalic congestive phenomena:** The stain usually begins on the face.
  • **Fetuses:** With a sterile gut, putrefaction is caused by bacteria entering from outside via the respiratory tract. Thus, the stain starts in the neck, face, and upper chest.
  • **Internal injuries without skin lesions:** The stain starts in skin areas close to the internal injuries, as these areas offer less resistance to bacterial development.
  • **Gangrenous, suppurative, and neoplastic diseases:** The stain appears around the lesions due to the prevalence of germs, leading to early putrefaction.

*Chronological Variations*

These variations depend on individual and environmental factors that influence putrefaction, causing accelerations, delays, and, at times, indefinite suspension of the process.