VMD 511: Animal Welfare, Ethics and Jurisprudence (2+0)

SUFFOCATION

• Exclusion of air from the lungs by means other than compression of the neck is termed as suffocation. Suffocation may cause death.

Causes of suffocation

• Smothering or closure of the mouth and nostrils
• Chocking or obstruction of the air passages from within
• Inhalation of irrespirable gases
• Smothering or closure of the Mouth and Nostrils
  • Calves are often accidentally smothered by being overlaid by their dams. A common method of killing the claves is to close the mouth and nostrils.
• Chocking or obstruction of the Air passages from within
  • Mostly accidental, this may be due to
    • Presence of foreign bodies – piece of carrot, potato, corn, coin, cork, rag, roundworm, mud, cotton, leaves in the air passage.
  • It is not necessary that the foreign body should be of big size as to block the air passages completely. Even a small object blocking the lumen partially may cause death by spasm.
• Inhalation of Irrespirable Gases
  • Inhalation of gases such as CO₂, an anaesthetic used by mistake carbon monoxide, hydrogen sulphide or smake from a barning house will produce suffocation.

Mode of death due to suffocation

• Usually death is due to asphyxia but it may be due to shock, when the heart stops y reflex action through the ragus nerves.
• Death occurs on an average from 10 to 15 minutes after complete withdrawal of air from the lungs. Death was almost instantaneous when the windpipe was blocked by a foreign body. Recovery may occur if treated with 5 minutes.

Postmortem Appearance

• External
  • Death may be due to the cause leading to suffocation or asphyxia.
  • Due to foreible application of the hand over the mouth and nostrils, bruises and abrasions may be found on the lips and edge of the mouth and alongside the nostrils. The inner surface of the lips may be found lacerated from the pressure on the teeth. Nasal septum may be fractured from pressure of the hand. These signs are very rare.
  • Bruises and Abrasions on the cheeks and malar regions or on the lower jaw, if there has been a struggle.
  • Rarely, Fracture or dislocation of cervical vertebral may occur if the neck has been forcibly wrenched in an attempt at smothering with the hand. If a soft cloth has been used to block the mouth and nostrils, there will be no signs of violence.
  • Signs due to Asphyxia – Suffocation
    • Eyes are open
    • Eye alls are prominent
    • Conjunctivae are congested
    • Lips are livid
    • Tongue is protruted
    • Bloody froth comes out of the mouth and nostrils
• Internal – P.M.changes – Suffocation
  • Mud or any other foreign matter may be found in the mouth, throat larynx or trachea if suffocation caused by impacted of a foreign substance in the air passage. Foreign matter may also be found in the pharynx and oesophagus.
  • Mucous membrance of trachea is usually rightred, covered with bloody froth and congested.
  • Lungs are congested and emphysematous.
  • Punctiform subplenral ecchymoses (Tardieu’s spots) are present at the root, ase and lower margins of the lungs may be present in asphyxial deaths from other causes. It is not characteristic of death by suffocation. Punctiform subpleural ecchymoses are also found on the thymus pericardium and along roots of the coronary vessels.
  • Lungs may be found normal, if death has occurred quickely.
  • Heart – Right side heart is full of dark fluid blood. Left side empty.
  • Blood does not readily coagulate. Wounds caused after death may bleed.
  • Brain – Generally congested
  • Liver, spleen and kidneys – found congested