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VIOLENT ASPHYXIA
Asphyxia means cessation of respiration. Violent asphyxia is a cessation of
respiration as a result of mechanical interference of respiratory mechanism due to
violence.
The development of this violent asphyxia may be due to:
I. Closure of the external respiratory orifices as in smothering and overlaying.
11. Closure of the air passages by external pressure on the neck as in hanging,
strangulation and throttling.
III. Closure of the air passages by the impaction of foreign bodies in the larynx or
pharynx as in chocking.
IV. Prevention of access of air owing to the air passages being filled with fluid as in
drowning.
V. Prevention of breathing by preventing the normal movements of the chest as in
traumatic asphyxia
PATHOPHYSIOLOGY OF VIOLENT ASPHYXIA
In all types of violent asphyxia, 02 starvation will occur, that interferes with
pulmonary ventilation, results in circulatory failure. Vital reaction to 02 starvation
depends upon:
1-The period between the onset of disturbance and the moment of death as vital
reaction is proportional to the period of anoxaemia.
2- The amount of struggles that had been done.
The nervous tissues are first affect by 02 starvation ranged from lack of concentration
up to permanent CNS damage if period of anoxaemia is up to ten minutes
GENERAL PATHOLOGICAL FINDINGS IN ASPHYXIA:
I. Visceral congestion
02 starvation in violent asphyxia results in capillary dilation followed by blood stasis
in both dilated capillaries and venules that accounts for visceral congestion.
It is not specific for asphyxial deaths as it occurs in death from shock.
2. Petechial hemorrhages
They are present everywhere externally as well as internally. They are most observed
in the serous membranes, particularly in the visceral pleurae and visceral pericardium
and they are called Tardieu spots
Two factors are concerned with the production of these petechiae.
1.Capillary bursting: due to increased intracapillary pressure as a result of
mechanical obstruction of venous return.
2.escape of blood into tissue due to increased capillary permeability as a result of
anoxia. Also, not specific as they occur in septicemia and heat stroke.
3. Cyanosis Occurs in: lobules of ear, tip of nose, nail beds hand, feet and dependant
parts due to: accumulation of reduced Hb in stagnant capillaries. Not specific as, it
may result from circulatory failure.
4. Post mortem lividity: In asphyxia deaths, lividity is well marked, deep blue and
extensive. This is due to the dark more fluid blood. It is position differs in relation to
the position of the body.
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5.postmortem fluidity
Blood is more fluid and dark within the heart and big vessels. This may be due to:
I- Decreased post mortem coagulability due to increased C02 and coagulation time.
2- Increased fibrinolytic activity of serum due to increased fibrinolysin production.
3- Disturbance in plasma calcium.
6. Structural changes:
a- Heart: greatly dilated right side of heart due to cardiac failure. Blood is more
fluid and dark.
b- Respiratory. system: congestion and petechiae in all respiratory tracts. The lungs
are congested and edematous with Tardieu spots and silvery spots (due to ruptured
air vesicles)
C- Central nervous system: hyperemia and scattered peteehiae in the brain more
marked in white matter. Irreversible degenerative changes in nerve cells occur
within 5 minutes of anoxaemia up to 10 minutes.
7. Biochemical changes:
Studies showed that the decreased 02 content, increased CO2. content and altered pH
of agonal blood are not diagnostic of asphyxial deaths.
I-Violence applied to external respiratory orifices
A. Smothering
It is obstruction to the passage of air into the respiratory tract- is caused by closing
the external respiratory orifices either by the hand or by other means.
Circumstances of smothering
1. Accidental smothering occurs in:
a. Persons under the influence of alcohol or narcotics and young infants who bury the
face in a pillow or covering it with bed clothes.
b. Collapse of buildings with inhalation of send and dust.
2. Homicidal smothering..
3. Suicidal smothering, It is uncommon.
Post mortem examination
1. Non specific general pathological changes.
2. Special pathological changes:
Externally:. Abrasions and contusion are found around nose and mouth related to
assailant’s hand. Nose may be distorted from continuous compression. Also there is
circumoral pallor in contrast to congested face; Signs may be minimal with non
resistant victims as infants and alcoholics.
Internally: Bruises and contused wounds may be found on the inner aspects
of the lips and cheeks and are caused by pressure upon the jaw and teeth. Some of
the teeth may be found loose or even broken.
cause of death
1. Immediate: Asphyxia of smothering.
2. Delayed: Aspiration pneumonia.
b. Overlaying
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It is a type of violent asphyxia. caused by a combination of compression of the chest
and abdomen, thus preventing respiratory movements in addition to closure of the
nose and mouth..
Circumstances of overlaying
Accidentally:
It is the commonest form in a newly born infant; sleeping with his mother in one bed.
Death here is either from leaving the mother’s breast in the mouth of the infant while
she is being overcome by sleep or from overlaying him thus causing death. Also may
occur from collapse of buildings or heavy crowds.
homicidally:
It occurs in the following conditions:
1) In the crime of infanticide.
In wrestling where the chest of the victim is squeezed with arms or legs.
Post mortem findings
1. Non specific general pathological changes
2. Special pathological changes
Externally: abrasions and bruises are found in relation to compressed parts as cheeks
and nose with bruising of the anterior chest wall and abdominal walls.
Internally, fractured ribs and ruptured organs may be present.
Cause of death
1- Asphyxia.
2- Ruptured organs.
II. Violence applied to the Neck (from outside)
A. Hanging
It is a constriction of the neck by a ligature, the constricting force being applied
indirectly to ligature through the weight of the body. Position of the hanged persons
in typical hanging is free hanging
Suspension is by a ligature usually a rope with a nooses which encircles the
neck. The noose may either be fixed when the rope is knotted or a running noose as
when the end of the rope is passed through a loop.
Ligature may be by cord. rope, belts, packing wires or twisted sheets
Circumstances of hanging
1- Accidental hanging
In children who hang themselves at play and in workmen during falling from
scaffolding.
2-Suicidal hanging: It is the commonest type of hanging.
It is confirmed by the presence of suicide notes, chair, tables, the manner of tying
the ligature and the material used, the presence of self inflicted antemortem wounds
may point out to previous attempts of suicide. Absence of signs of resistance on the
body and at the scene of hanging is evidences for suicidal hanging.
3. legal hanging (justical hanging):
it is the method of execution in Sudan.
4-Homicidal hanging (or lynching): It is rare.
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Postmortem suspension:
It is more common than true homicidal hanging. It is done after other
types of murder had been committed to conceal the real crime.
Postmortem examination
1. Non specific general pathological changes
2- General external appearance:
The head is inclined to the side opposite to the knot with stretched neck.
- The face is pale but may be swollen and congested with prominent eyes
- The tongue is drown in or caught between, the teeth or protruded and bitten. Blood
froths are seen at the mouth and nostrils. Saliva may be dribbling from the mouth if
the knot in the ligature is on one side with tilting of the head to the other side. It is an
important sign of antemortem hanging as the secretion of saliva is a vital function:
- The postmortem lividity is most marked in the legs, hands and feet.
3- Specific external appearance
Externally:
1. The head is bent on the chest, if the point of suspension was found from the back
with stretched neck
2. Ligature mark:
a. Pattern:
Ligature mark in hanging is a type of pressure abrasion.
b. Position
Usually the ligature is situated above the thyroid cartilage.
c. Course
In typical hanging (fixed noose) when the ligature is tied posterior the ligature runs
from the middle line above the thyroid cartilage symmetrically upwards on both sides
of the neck to be deficient at the occipital region i.e. the point of suspension, caused
by the head falling away from the rope.
When a running noose has been used, the weight of the body will cause the noose to
tighten in a horizontal position. The groove left will also be horizontal but there may
be an additional vertical mark caused by the suspending ligature
d. Depth
The depth of the ligature mark is related to the amount of pressure exerted as well as
the nature of the ligature.
e. Color
The pressure abrasion is brown. There may be a thin line of blue color in the front
and along the lower edge of the mark. It represents minute areas of bleeding due to
rupture of the small blood vessels in the skin and is of vital importance as it
indicates that the person was alive at the time of hanging.
f-Width
This is related to the nature of the ligature e.g. a firm string produces a narrow and
deep depression . while a strap would produce a wider one.
Internally:
1. The tissues under the mark are dry, anemic and compressed with occasional
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ecchymosis and torn platysma muscle.
2. The intima and media of the carotid arteries are lacerated with
extravasations from the vasa vasora. It is a valuable sign pointing to suspension
during, life.
3. There is contusion in the posterior pharyngeal wall caused by the backward
displacement of the tongue.
4. The hyoid bone and thyroid cartilage may be injured.
5, Fracture dislocations of the cervical vertebrae (judicial hanging).
Causes of death
1. Asphyxia by blocking the air passages the pressure of the ligature leads, to
compression of the tissues of the neck and forces the base of the tongue upwards and
backwards against the posterior pharyngeal wall, pushes the soft palate and uvula
upwards and depresses epiglottis over the laryngeal opening.
2. Anoxaemia of the brain: compression of the principal venous trunk will prevent
venous return of the brain leading to stasis and brain anoxaemia,
3. Anemia of the brain: Compression of the neck will compress the carotid arteries
with rapid loss of consciousness.
4. Syncope: It is caused by pressure on the vagus nerve and carotid sinus.
5-Injury to spinal column and cord: It occurs in judicial hanging. It results in fracture
cervical one and two and dislocation of the odontoid process with resultant
laceration of the medulla oblongata and injury to the vital centers.
Strangulation by ligature
It is an act of violence whereby the constriction is applied directly to the neck by
a constricting band. The ligature is tightened directly by the hand of a
murderer.
Circumstances of strangulation:
Accidental strangulation
* By umbilical cord during delivery.
* In Children during playing with a rope.
Among porters by slipped rope from the forehead down to neck.
*Also in adults if clothes are caught in machine.
Suicidal strangulation:
This is uncommon as a method of suicide. It may be achieved by using ligature
with rough or adhesive surfaces, by multiple loose turns round the neck. The
ligature mark will be a faint band of pallor with little damage to neck
structures. The absence of ante-mortem violence is essential for diagnosis of
suicide.
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• Homicidal strangulation:
This is the commonest form of strangulation. Sign of resistance on the
body as well as in the scene are present. Other injuries as laceration of the
scalp, stab wounds or evidence of rope may be found. An evident motive
to homicide as robbery favors the diagnosis of homicide. The nature of the
ligature and the way of its fixation and the site of the knot are important
points in the diagnosis. Sometimes the assailant burns the body to conceal
the crime, yet the mark may be not completely destroyed by fire.
Post mortem signs:
I. Non specific general pathological changes
2- General external examination:
- Presence of signs of resistance on the body in the form of finger nails abrasions
and contusions.
- Congested face, protruded eyes ,the conjunctivae are congested with
subconjctival hemorrhages. The tongue may be protruded. Fine blood tinged
froth sometimes is found at the mouth and nostrils. Blood oozing from ear, nose
and mouth is commonly seen.
- Hypostasis is of deep blue color and has no specific site.
3 - Special examination of the neck:
External examination:
The ligature may be put round the neck and the ends crossed and pulled tight or
it may be applied and knotted. The knot is usually at the front or side. The
ligature May be removed and only ligature mark-is left.
The ligature mark
It depends upon the kind of ligature used, direction and violence of the constricting
force and whether the constricting force is maintained after death or not.
Pattern: Ligature mark in strangulation is a type of pressure abrasion
Number: A single external mark is usually present on the neck, but more than one
mark may be found.
Course: The mark usually encircles the neck completely and is directed transvers1y
across the neck, but will be broader at the site of the knot.
Position: The ligature mark may be situated in any region but usually present at the
level of the thyroid cartilage.
Depth: The mark is most marked and deepest in cases where the ligature used is
made of hard material as a firm rope or a wire.
Color: a brown color. Abrasions and bruises are commonly found in the surrounding
skin caused by the hands of the assailant or the hands of the victim in an attempt to
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release the pressure.
internal examination
Bruising and laceration of the neck muscles are common. Fractures of hyoid bone are
unusual, while fractures of thyroid cartilage at the level of the ligature may occur
unless the victim is young and the cartilage is elastic.
Cause of death:
1. Asphyxia: owing to the pressure of the ligature on the air passages.
2. Reflex cardiac inhibition caused by pressure on carotid sinus and vagus nerve.
3. Obstruction of the carotid arteries and internal jugular veins will lead to brain
anoxia and syncope.
Special types of strangulation
1. Infanticide: the umbilical cord is used as a ligature; it will show displacement of
Wharton’s jeIly from areas of pulling. The cord will show displacement .A complex
type of knotting is present.
2. Garroting:. the victim is attacked in the dark from behind. A bandage is thrown
around his neck and suddenly tightened to attain robbery.
3. Judicial strangulation: It was a method of execution in Spain. It was carried out
with a constricting device thrown as a garrote which when tightened also pierced the
back of the neck and spinal cord with a dagger.
4. Fabricated strangulation: The person may charge another with attempted murder
by strangulation. In this case, strangulation is mild, the ligature is loose and not
secured as to press with great force on the air passages, to cause the tongue to
protrude etc... i.e. non fatal ligature.
N.B :Whenever a victim with a rope around his neck is examined we have
to decide whether death was due to hanging or strangulation.
The following differentiating points are important:Point
Hanging
Strangulation
Force
Weight of the body
From outside
ligature itself
Hypostasis
In lower limbs
Anywhere
Blood oozing
Not seen
From ear, nose and mouth
Neck
Stretched and elongated
Not
Saliva
Dribbling from the mouth
Not present
Ligature mark
Incomplete
Complete
High up
Lower than hanging
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on
the
More oblique
transverse
Depressed
More depressed
Site of knot absent
Apparent
Usually one mark
May be more than one
Hyoid bone
May be injured
Always not injured
Thyroid cartilage
Process
of
cartilage is torn
Carotid artery
Intema and media are torn
Not torn
Retropharyngeal bruises
present
Absent
Spinal column
May be fractured
Not common at all
Signs of resistance
Absent
Present
thyroid May be torn
C. Throttling (Manual strangulation)
It is the application of force to the neck of a person. The constricting force is the
hands
Circumstances of throttling:
Suicidal throttling:
It is uncommon as the rapid unconsciousness which occurs. Would cause the hand to
loosen their grip. Yet in rare cases when cadaveric spasm sets in the muscles of the
hands and the pressure is maintained death will occur as in lunatics.
Homicidal throttling:
It is very common, in all ages especially infants or over powered adults. It occurs
alone or in association with other violence as smothering overlying or rape to
prevent shouting. A special type of homicidal throttling is called Mugging; in which
pressure on the neck is applied by the forearm, the assailant being behind the victim.
It results in laxation of the right thyrocricoid articulation and its ligament is torn with
hemorrhage. In wrestling this type of violence is known as “strangle-hold” and it is
now prohibited due to its danger.
Accidental throttling
It may occur in cases of ordinary quarrels and assaults with no intention to cause
death. Examination reveals the diagnostic signs of throttling. The accidental nature of
the condition can be proved by the circumstantial evidence and by the witnesses.
Post mortem examination:
1- Non specific general pathological changes
2-General external examination reveals cyanosis of the face and lips.
Multiple petechial hemorrhages in the skin of the face, eyelids, scalp, and ear drums
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and in conjunctivae are common. In addition, bruises and abrasions around the nose
and mouth and are resulted from the attempts of the assailant to prevent the victim
from crying or as signs of resistance in an attempt of the victim to remove the
assailant’s hands.
It is also found in the scalp tissues over the back of the head and posterior surfaces
of the shoulder blades. Bruising of these regions is usually found in cases where the
victim has been forced to the ground.
3- Specific examination of the neck:
Externally:
The nature and extent of the lesion depends upon:
I The method of throttling: one hand- both hands -forearm of the assailant
2-The attack was from the front, back or sides of the victim’s neck.
3-Right or left handed assailant.
When the assailant uses one hand and the attack is from the front of the victim, the
upper part of the neck immediately below the angle of the jaw is usually gripped.
There will be bruises caused by the fingers and crescentic abrasions caused by
fingernails impressions on both sides of the neck, There is usually a single big
abrasion on the right side of the neck caused by the thumb and grouped abrasions on
the left side due to pressure of the other 4 finger which are indication of a right
handed compression of the throat. Multiple abrasions &bruises may be found on the
front and sides of the victim’s neck. These may be produced by one hand with
changing grip or by both hands or by more than one person. Victim’s fingers may
also produce them and nails mixed with assailant’s marks, in an attempt to deliver his
neck from the assailants hand (s). The number and direction of abrasions may help
in identity of the assailant if he has one or more missing fingers. The external marks
may be absent in the following conditions
1, When the assailant places a thick towel over the victim’s neck before
throttling.
2. If the assailant’s nails pared
3, When the forearm is used instead of the hand as in mugging.
internally:
1. Extensive bruises are usually found in the deeper layers of skin, fascia, muscles of
the neck, as well as in the substance of the thyroid gland.
2.Fractures of the hyoid bone are commonly found in throttling and are accompanied
by hemorrhage at the site of fracture. Fractured hyoid bone is a diagnostic sign for
throttling even in a putrefied body.
3. Fracture of other laryngeal cartilages occurs depending on the hands grip and age
of the victim.
Causes of death
1. Sudden pressure on the carotid sinus, vagus nerve or its superior
Laryngeal branch results in immediate death from reflex vagal inhibition and cardiac
arrest. If the pressure was below the carotid sinus death is due to ventricular
fibrillation.
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2. Obstruction of the carotid arteries and internal jugular veins will lead to brain
anoxia and syncope.
3. Pressure on the neck by hands constricts the larynx leading to asphyxia.
IlI Violence applied to internal air passages
Chocking
It is the obstruction of air passages by impaction of foreign bodies,
e.g. aspirated vomitus, stomach contents or food material after artificial feeding,
blood, mucous, saliva or amniotic fluid. The choking agent may be sold semisolid
or fluid in different sizes and amounts. The site of obstruction could be at the
pharynx, larynx, trachea, bronchi or smaller bronchioles.
circumstances:
Accidental:
• It is the most common cause of accidental asphyxia.
*lt is common among children by putting any accessible objects in their mouths e.g.
marbles, coins, peanuts, buttons. These objects may pass into the larynx or trachea
during a sudden deep inspiration
*Also during feeding, fish bone and chicken bones may be impacted in the wall of
larynx with resultant laryngeal edema.
Among alcoholics, intoxicated and old persons with disturbed deglutition reflex by
food or dentures.
During anesthesia by the backwards displacement of the tongue and post-operative
chocking may occur by missing a pack in the posterior
pharyngeal wall or from aspiration of blood, vomitus or broken dentures.
Homicidal choking:
In infanticide crime, where the foreign material may be pushed violently into the
mouth e.g. towel, piece of cotton. Laceration and hemorrhage of the gums and palate
are found due to rough impaction.
Suicidal choking:
It is uncommon and may occur by lunatics.
Post mortem examination
General examination
it reveals non-specific appearance.
Local examination:
Bruises and abrasions of the air passage are found especially if the foreign body is a
solid one, presence of foreign body is confirmatory evidence. In the delayed death,
pathological changes in the lungs will be apparent e.g. consolidation, lung abscess.
causes of death:
1. Asphyxia of choking: caused by a large foreign body which, becomes impacted in
the pharynx and cover the laryngeal opening e.g. a piece of meat, thus preventing the
access of air completely.
2. Cardiac arrest: by induction of laryngeal spasm.
3. Laryngeal edema: The foreign body may be too small to cause obstruction, yet
death takes place by laryngeal edema which is due to irritation at the site of
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impaction. This edema results in both anoxia as well as reflex vagal inhibition.
Delayed causes of death
1.Aspiration pneumonia.
2.Lung abscess.
3.Bronchiectasis.
IV. Violence at the level of the chest:
Traumatic or crush asphyxia:
It is due to compression of the body or chest by some heavy weight e.g. run over by a
vehicle driver. The chest is thus compressed and the diaphragm fixed by compression
of the legs and abdomen forces blood into the head. Thus a characteristic appearance
of the victim comprises deep engorgement and cyanosis with multiple hemorrhage in
the skin of the face and upper chest. There are swelling and edema of the eyeballs
and subconjunctival hemorrhages with relative pallor of the lower half of the body.
The damage will include fractures of ribs with ruptured internal organs.
Drowning
It is an asphyxia death due to continuous or intermittent submersion or partial
submersion in a fluid. Drowning usually occurs in water (salty or fresh) and may
occur in chemical solutions i.e. dye or paint
The circumstances of drowning:
Accidental drowning:
This is the commonest form and is seen in the drowning of bathers, fishermen, and
children, may be adults usually epileptics or intoxicated subjects. The body is usually
found naked and free from injuries. Also accidental drowning takes place in boat
accidents when one or more persons will be found fully dressed.
Suicidal drowning:
It is a common method of self-destruction among persons who live near to a river or
sea. Antemortem injuries are sometimes found in the drowned body due to previous
attempts at suicide or due to striking hard objects during its fall in the water. The
person may tie his hands or feet and may put stones in his pockets to ensure long
submersion.
Homicidal drowning
It is very rare. It is proved only by the circumstantial evidence and by
finding marks of resistance on the body. It may occur from pushing a person into a
river or the sea. There must be physical disproportion between the assailant and his
victim or the victim is incapacitated by disease, drink or drugs, or is taken by
surprise. Evidence of pressure on the back of the head or rest of the body may be
found to ensure submersion.
Postmortem submersion
Bodies may be thrown into water after being killed by other means. Heavy
objects are tied to the body to keep it under water for a long period. Sure signs of
drowning are absent. Other cause of death are found e.g. strangulation, head injuries.
Mechanism of drowning:
When a non swimmer falls into the water, he first sinks and shortly afterwards,
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through the natural movements of the body he rises to the surface, such rise is
accompanied by forcible expiration of some of the air, when he cries for help and
struggles he inhales water which induces coughing and his struggles increases and
again he sinks. If this occurs at a moment of inspiration he will inhale more water.
The process of sinking and rising may be repeated until water replaces most of the
air in the air passages and lungs and he remains submerged. There is usually a brief
convulsive phase followed by coma and death. The body remains on the bed of the
river or sea until putrefaction sets in causing floatation of the body.
Drowning in Fresh water and seawater
Fresh water is hypotonic with respect to blood and is absorbed rapidly from the
lungs, causing haemolysis and haemodilution. which overloads the circulation with
excess plasma K and sodium loss. A rapid and considerable fall in systolic blood
pressure will occur and within minutes ventricular fibrillation results.
[)rowning in seawater is different. It is characterized by aspiration of hypertonic
fluid, which draws water from pulmonary capillaries into alveoli causing marked
edema. There will be haemoconcentration and the haematocrit and plasma sodium
levels increase. The end result will be myocardial anoxia and rapid cardiac failure..
Post mortem picture - unsure signs due to submersion in water
A. unsure signs sign due to submersion in water.
B. sure Signs due to drowning
A- Signs due to submersion in water.
These signs are apparent in bodies recovered from water and will occur in bodies
immersed in water before or after death from causes other than drowning, so they are
not reliable to diagnose drowning.
1.Cooling of the body when recovered as cooling in water occurs at about twice the
rate of cooling in air.
2. Post mortem Hypostasis may be confined to the head neck and front of the chest
and usually bright pink in color.
3. Gooses flesh due to contraction of the erectors pilorum muscles and may be
produced by rigor mortis.
4. Washerwoman’s hands and feet due to long submersion in water.
5. The conjunctivae are congested and scanty subconjunctival petechial hemorrhage
may be seen.
6. Peeling of the epidermis or gloving due to prolonged submersion where the skin
may come off the fingers in the form of gloves.
7. The tongue is often found between the jaws. A bruised or bitten tongue may point
to a struggle during or prior to drowning or to an epileptic fit as a result of which the
victim fell into water.
B. SIGNS DUE TO DROWNING
These are diagnostic signs and are caused by drowning
External signs:
1. The presence of foam at the mouth and nostrils
This foam appears as small balloon, white or pinkish in color. It is persistent, and
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increased by pressure on the chest. It is a Vital phenomenon. The entry of fluid into
the air passages provokes them to produce mucous. Due to violent respiratory efforts
made by the victim, the mucous mixes with inspired water, residual air and also
surfactant from the lungs to make froth.
Cadaveric spasm
Aquatic objects e.g. weeds, sand, gravel may be held in the hands or feet. It is a vital
reaction Abrasions on the fingers and tearing of the nails may occur when the victim
grasps objects in an attempt to save himself.
Internal signs:
Respiratory system
I. Foam ,a variable amount of water, sand, weed and diatoms are present in the
respiratory passages.
2. The larynx may be congested.
3. The pleurae reveal subpleural hemorrhages. They are shining pale bluish red in
color and are usually present in the lower lobes of .the lungs. Tearing of the interalveolar septa produces them. The pleural cavities reveal blood stained fluid
4.The lungs (emphysema aquosurn).
Are ballooned and overlap the pericardium. Being loaded with water they pit on
pressure and rib markings are usually present, They are pale in color by the filling up
of the air cells with water. The cut surface of lungs will contain foamy water with
diatoms, sand, sea weed similar to the medium in which drowning takes place.
B. Circulatory system:
Obstruction of the pulmonary circulation due to the inhalation of water results in
right heart and the great veins, which are filled with dark fluid blood. Haemolysis of
the blood may be apparent.
C. Digestive system
The stomach may contain fluid that shows the same composition as that of the
submerging medium e.g. weeds algae or diatoms.
Causes of death in drowning:
A. Rapid death:
1.Asphyxia of drowning.
2.Electrolyte disturbances,.
3. Hypothermia may develop rapidly in cold water. Sudden unexpected immersion
into cold water can cause death by:
A Cardiac failure due to rises in venous and arterial pressures .
B. Ventricular fibrillation.
C. Inhalation of water due-to respiratory distress.
4. Laryngeal spasm or dry drowning
It is provoked by the entry of water into the larynx and will be the prime cause of
death. The normal process of drowning will not take place.
5. Fatal head injuries during diving into the water.
B. Delayed cause of death or secondary drowning or post-immersion syndrome.
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Apart from death during submersion, a person may survive this period but
subsequently suffer complications or die from the delayed effects of inhalation of
water e.g.
1. Inhalation pneumonitis. .
2. Bronchopneumonia. .
3. Abscess formation (submersion in infected water)
4. Pulmonary edema.
5. Renal failure caused by excessive red cell destruction.
6. Myocardial anoxia may cause delayed heart failure.
Confirmatory evidence of drowning:
1-The nature of the water in the lungs:
To differentiate between water inhaled, in drowning from the serous fluid in
pulmonary edema. This may be done by microscopical examination of water exuding
from the lung surface for algae, diatoms ... etc.
2..Biochemical tests on blood
A-Gettler’s test:
it is based on the difference between the chloride content of blood samples taken
from the right and left sides of the. heart. Thus in fresh water drowning, the blood on
the left side of the heart will be diluted in comparison to that of the right side and so
will have a lower chloride level than the right side whereas in sea water the reverse
will occur. These tests are only reliable if done within about 24 hours after drowning,
before putrefactive changes.
B-Diatoms tests
The demonstration of plankton and diatoms microscopically in the submerging fluid
and in the body of the victim is a confirmatory test of drowning. Diatoms are present
in the lungs, liver brain and bone marrows; even they are strong evidence in
advanced state of putrefaction which amounts to skeletonization. Their size, shape
and number differ from one place to another.
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