What is Putrefaction?
Putrefaction is the term used for the process through which organic matter undergoes microbial decomposition and produces an unpleasant odor. This occurs after 10 to 20 days after the organism’s death. Several things happen during the putrefaction process, including the breakdown of proteins, the breakdown of tissue cohesion, and the liquefaction of most organs. The body’s tissues and organs decay as a result of the putrefying bacteria and fungi that spread throughout the body. They are crucial in the process of recycling nitrogen from decomposing organisms.
Putrefaction is regarded as the fifth stage of death, after Pallor Mortis (paleness of the skin), Algor Mortis (change in body temperature), Rigor Mortis (rigidity in the movements of a corpse), and Livor Mortis (settling of blood on the lower side of the body).
Also Read: Autopsy
Signs of Putrefaction
The first visible sign of putrefaction is a greenish discolouration of the skin of the anterior abdominal wall. This commonly begins in the right iliac fossa, i.e. over the area of the caecum, but occasionally, the first changes are peri-umbilical, or in the left iliac fossa. The discolouration, due to sulph-haemoglobin formation, spreads to involve the entire anterior abdominal wall, and then the flanks, chest, limbs and face.
Bacillus and Pseudomonas, aerobic bacteria, are the most common putrefactive microorganisms.
Process Of Putrefaction
After death, biological organisms begin to chemically degrade into amino acids as a result of an interaction with water, a process known as hydrolysis. The breakdown of proteins in a rotting corpse occurs spontaneously. Protein hydrolysis is accelerated when the anaerobic bacteria of the digestive system devour, digest, and expel the cellular proteins of the body.
Bacterial digestion of cellular proteins weakens the body’s tissues. As the proteins are continually broken down to smaller components, the bacteria emit gases and organic chemicals, such as the functional-group amines putrescine (from ornithine) and cadaverine (from lysine), which convey the foul stench of decaying flesh. The putrefaction gases are first limited within the bodily cavities, but gradually spread through the adjacent tissues and into the circulatory system. The putrid gases seep and disperse to different areas of the body and limbs once they enter the blood vessels.
Bloating of the torso and limbs is a visible sign of gaseous tissue infiltration. The increased internal pressure of the gas’s continually rising volume strains, weakens, and separates the tissues that restrain the gas. The epidermal tissues of the body ultimately tear and expel the bacterial gas during putrefaction. As anaerobic bacteria continue to consume, digest, and excrete tissue proteins, the body’s breakdown continues to the skeletonization stage.
What Factors Affects Putrefaction?
Two kinds of factors can be observed which affect the putrefaction:
- External Factors
- Internal Factors
● Environment: A rise in temperature boosts the rate of putrefaction. The ideal temperature to maintain during the putrefaction process is 21°C to 38°C. Temperature is below 0°C or over 48°C interferes with the putrefaction process.
● Moisture: Lack of air or if a body is immersed in water the putrefaction process slows down. Microbes develop in the presence of moisture and air, causing the organism to degrade.
● Clothing: Loose or fit clothing also interfere with putrefaction process.
Also Read : Decomposition of Body
● Age: When compared to an older individual, a youthful person’s body decomposes at a faster rate. Infants and fetuses, on the other hand, have sluggish putrefaction since their bodies are sterile.
● Body Condition: Because overweight bodies contain more heat and fluids, they decompose faster than lean bodies.
● Cause of Death: When compared to persons who died in accidents, people who died from infectious disorders undergo the putrefaction process more rapidly.
● External Injuries: The putrefaction process is facilitated by the presence of bacterial invasions on injured bodies.
Approximate Timeline of Putrefaction
The following is an approximate timeline of events during the putrefaction stage:
- 1–2 days: Pallor mortis, algor mortis, rigor mortis, and livor mortis are the first steps in the process of decomposition before the process of putrefaction.
- 2–3 days: Discoloration appears on the skin of the abdomen. The abdomen begins to swell due to gas formation.
- 3–4 days: The discoloration spreads and discolored veins become visible.
- 5–6 days: The abdomen swells noticeably and the skin blisters.
- 10–20 days: Black putrefaction occurs, which is when noxious odors are released from the body and the parts of the body undergo a black discoloration.
- 2 weeks: The abdomen is bloated; internal gas pressure nears maximum capacity.
- 3 weeks: Tissues have softened. Organs and cavities are bursting. The nails and hair fall off.
- 4 weeks: Soft tissues such as the internal organs begin to liquefy and the face becomes unrecognizable. The skin, muscles, tendons and ligaments degrade exposing the skeleton.
Order of organs decomposition in the body:
- Larynx and trachea
- Infant brain
- Omentum and mesentery
- Adult brain
- Blood vessels
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