7- Drowning (Immersion):. It is a form of violent asphyxia in which death results from submersion of mouth and nostrils of a living person under water. Classification (types) of drowning : 1- Typical (wet) drowning: 2- Dry drowning. 3- Secondary drowning (Near-drowning).
It is a form of violent asphyxia in which death results from submersion of mouth and nostrils of a living person under water • Classification (types) of drowning: 1- Typical (wet) drowning: 2- Dry drowning. 3- Secondary drowning (Near-drowning).
Physiopathological changes: • In fresh water hypervolemia hypoxia and potassium excess. • In salt water pulmonary edema hypovolemia and circulatory shock.
Dry drowning: Water in the larynx laryngeal spasm asphyxia Near-drowning (2nd drowning syndrome):
PM picture of drowning: • These are signs of asphyxia unless death occurred from 1- shock, 2- syncope, 3- concussion.
External appearances • Signs of immersion: These are found in any body found dead in water (whatever the cause of death). • Coolness of the body. • Goose-skin the skin is wrinkled. • Washerwoman-skin: the skin is sodden. • Peeling of the epidermis in the form of gloves and stockings. • Hypostasis
2- Sure external signs: A-Froth: (Fine – White – Odorless _ increase) B-Cadaveric spasm of the hands on weeds, mud, sand, etc.
Internal appearances • Voluminous lungs with indentation marks of ribs on their lateral surfaces. • Respiratory passages contain froth (having the same characters of that found externally at the mouth and nostrils), • foreign material ( weeds, mud, sand,.).
Diatoms: • These are microscopic, unicellular algae, found in fresh as well as salt water. • When a live person is drowned in water, they penetrate his alveolar membrane and pass with the circulation to distant organs. • But when a dead body is thrown into water, the absence of beating heart prevents circulation of diatoms to distant organs.
The medico-legal (ML) importance of diatoms: • 1- Sure signs of drowning, • 2- Could still be identified in putrefied bodies, • 3- Could give an evidence of the site of drowning (fresh or salt water species).
How to know that death was due to drowning: 1-Froth at mouth and nostrils: fine, white, abundant. 2.Cadaveric spasm on weeds, mud or sand. 3.Lungs: voluminous, edematous with indentation marks of the ribs. 4.Froth in the air passages. 5. Diatoms in the tissues.
In putrefied bodies: • Only diatoms could be identified