77 - -Drowning Drowning (Immersion)(Immersion)::

It is a form of violent asphyxia in which death It is a form of violent asphyxia in which death results from submersion of mouth and results from submersion of mouth and nostrils of a living person under waternostrils of a living person under water

• Classification (types) of Classification (types) of drowningdrowning::

1- Typical (wet) drowning: 1- Typical (wet) drowning: 2- Dry drowning.2- Dry drowning.3- Secondary drowning (Near-3- Secondary drowning (Near-

drowning).drowning).

Physiopathological Physiopathological changeschanges::

• In fresh water In fresh water hypervolemia hypervolemia hypoxia and potassium excess.hypoxia and potassium excess.

• In salt water In salt water pulmonary edema pulmonary edema hypovolemia and circulatory hypovolemia and circulatory shock.shock.

Dry drowningDry drowning::

Water in the larynx Water in the larynx laryngeal spasm laryngeal spasm asphyxia asphyxia

Near-drowning (2nd drowning syndrome):

glistening pleural surface of a lung

PM picture of drowningPM picture of drowning::

• These are signs of asphyxia unless These are signs of asphyxia unless death occurred from death occurred from

1- shock, 1- shock, 2- syncope,2- syncope,3- concussion.3- concussion.

External appearancesExternal appearances1.1.Signs of immersionSigns of immersion::These are found in any body found dead in These are found in any body found dead in

water (whatever the cause of death).water (whatever the cause of death).• Coolness of the body.Coolness of the body.• Goose-skin the skin is wrinkled.Goose-skin the skin is wrinkled.• Washerwoman-skin: the skin is sodden.Washerwoman-skin: the skin is sodden.• Peeling of the epidermis in the form of Peeling of the epidermis in the form of

gloves and stockings.gloves and stockings.• HypostasisHypostasis

2- Sure external signs:2- Sure external signs:

A-Froth:A-Froth:(Fine – White – Odorless _ increase) (Fine – White – Odorless _ increase)

B-Cadaveric spasmB-Cadaveric spasm of the hands on weeds, mud, sand, of the hands on weeds, mud, sand,

etc.etc.

Internal appearancesInternal appearances

• Voluminous lungs with indentation Voluminous lungs with indentation marks of ribs on their lateral surfaces. marks of ribs on their lateral surfaces.

• Respiratory passages contain froth Respiratory passages contain froth (having the same characters of that (having the same characters of that found externally at the mouth and found externally at the mouth and nostrils),nostrils),

• foreign material ( weeds, mud, sand,.).foreign material ( weeds, mud, sand,.).

A normal pink aerated appearance with minimal anthracotic

pigmentation ,

Diffuse alveolar damage in which the lung is diffusely firm and rubbery

DiatomsDiatoms::

• These are microscopic, unicellular algae, These are microscopic, unicellular algae, found in fresh as well as salt water. found in fresh as well as salt water.

• When a live person is drowned in water, When a live person is drowned in water, they penetrate his alveolar membrane they penetrate his alveolar membrane and pass with the circulation to distant and pass with the circulation to distant organs.organs.

• But when a dead body is thrown into But when a dead body is thrown into water, the absence of beating heart water, the absence of beating heart prevents circulation of diatoms to distant prevents circulation of diatoms to distant organs.organs.

some of the plant material in the water was aspirated into a bronchus.

The medico-legal (ML) importance of The medico-legal (ML) importance of diatomsdiatoms::

• 1- Sure signs of drowning,1- Sure signs of drowning,• 2- Could still be identified in putrefied 2- Could still be identified in putrefied

bodies,bodies,• 3- Could give an evidence of the site 3- Could give an evidence of the site

of drowning (fresh or salt water of drowning (fresh or salt water species).species).

How to know that death was How to know that death was due to drowningdue to drowning::

1-Froth at mouth and nostrils: fine, white, 1-Froth at mouth and nostrils: fine, white, abundant.abundant.

2.Cadaveric spasm on weeds, mud or 2.Cadaveric spasm on weeds, mud or sand.sand.

3.Lungs: voluminous, edematous with 3.Lungs: voluminous, edematous with indentation marks of the ribs.indentation marks of the ribs.

4.Froth in the air passages.4.Froth in the air passages.5. Diatoms in the tissues.5. Diatoms in the tissues.

In putrefied bodiesIn putrefied bodies::

• Only diatoms could be identifiedOnly diatoms could be identified