‫بسم ا الرحمن الرحيم‬
yaseen.muhammad50@face
book.com
definition
conditions
stages
causes
mechanism
classification
pm findings/ext/internal
Definition:
• Conditions in which the supply of oxygen to the
blood and tissues has been reduced below the
normal working ...
Definition
Any condition that
obstruct respiratory passages or
interferes with respiratory process
resulting in a lowered ...
Mechanical Asphyxia
ASPHYXIA
• Interference with oxygenation – any where from
environment down to cellular level
Mechanical Asphyxia
CAUSE S OF ASPHYXIA:
 Environmental
 Obstruction of external respiratory passages
 Obstruction of i...
Mechanical Asphyxia
MECHANISMS
 Environmental
 Low or no atmospheric oxygen e.g. ships holds
 Scuba diving, surgical an...
Mechanical Asphyxia
 Throttling

 Ligature Strangulation
 Hanging
 Traumatic asphyxia
 Sexual asphyxia
 Positional a...
Mechanical Asphyxia
SUFFOCATION
 Obstruction of mouth and nose
 Smothering / overlaying / plastic bags

TRAUMATIC
 Pres...
Mechanical Asphyxia
STRANGULATION

 Obstruction of air way at the level of larynx by a
ligature directly applied on the n...
Mechanical Asphyxia
MECHANISM OF DEATH
 Oxygen deprivation
 Carbon dioxide accumulation
 Reduced blood flow to and from...
Mechanical Asphyxia
PATHOLOGICAL CHANGES
• General
▫ Cyanosis
▫ Congestion
▫ Engorgement right side heart
▫ Fluidity of bl...
Classify Mechanical Asphyxia;
what are specific pathological changes
in mech asph,
give one point in favour for each type
...
Mechanical Asphyxia
PATHOLOGICAL CHANGES
• Specific – Injuries to the larynx
▫ Hyoid bone
▫ Thyroid cartilages
▫ Cricoid c...
Mechanical Asphyxia

Sexual / Autoerotic Asphyxia / Autoerotic
Deaths


Accidental hangings, failure of safety mechanisms...
Mechanical Asphyxia
POSITIONAL ASPHYXIA
 Bodily position which obstructs airway or
impairs act of breathing
 Typically a...
Mechanical Asphyxia
• Environmental asphyxia
▫ Due to lack of oxygen in the environment
Mechanical Asphyxia
SUFFOCATION
 Obstruction of nose and mouth
 Homicidal, soft smothering
 "Overlaying"
 Plastic bags...
Mechanical Asphyxia
CHOKING


Obstruction of upper airway or glottis



Gag, homicide, rarely suicide



Accidental in ...
Mechanical Asphyxia / Throttling
THROTTLING (Manual Strangulation)
Form of mechanical asphyxia where neck structures
are c...
Mechanical Asphyxia / Throttling


General signs of asphyxia
 Congestion of face / bleeding from mouth and nose



Evid...
Mechanical Asphyxia / Strangulation
STRANGULATION
 Air way obstruction at larynx from pressure by a
ligature / garrotting...
Mechanical Asphyxia / Strangulation
 Bruises, abrasions
 Neck muscle haemorrhages, thyroid cartilage
fractures
 Suicide...
Mechanical Asphyxia / Strangulation
MECHANISM OF HYOID BONE FRACTURE
• Direct compression
• Indirect – pull on the thyro h...
Asphyxia or asphyxiation

• (from Greek α- "without" and sphyxis,
"heartbeat") is a condition of severely deficient
supply...
Asphyxia can cause coma or death
 the constriction or obstruction of airways, such as
from asthma, laryngospasm, Respirat...
Other causes of oxygen deficiency
include

Carbon monoxide inhalation, such as from a car
exhaust:
carbon monoxide has a h...
•
•
•
•
•

Ondine's curse,
central alveolar hypoventilation syndrome
Acute respiratory distress syndrome.
Hanging
Drowning
Ondine's curse
 , also called congenital central
hypoventilation syndrome (CCHS) or
primary alveolar hypoventilation, is ...
Stages of asphyxia
1- Stage of dyspnea:
. 2- Stage of convulsions:
. 3-Stage of apnea
(respiratory paralysis

The respirat...
Respiratory centre is divided four
major groups
• Inspiratory centre (Dorsal respiratory
group)
• Location: Dorsal portion...
Expiratory centre (Ventral respiratory
group)
 Location: Antero- lateral part of medulla, about

5 mm anterior and latera...
Pneumotaxic centre










Location: Pons(upper part )
Nucleus: Nucleus parabrachialis
Function: It controls bot...
Respiratory center depression
• Depression of a respiratory center can be a result
of next reasons:
• medical drug action ...
A convulsion is a medical condition where body muscles contract and relax
]
.rapidly and repeatedly, resulting in an uncon...
General Post Mortem Appearance
External Appearances:.Face: oedematous and congested.
.Eye: proptosis due to retro-orbital ...
Petechial Hemorrhage
Sites of formation:
in the skin and eyes
, particularly the eyelids, conjunctiva, sclera, face
)
lips...
Mechanism of formation
• The hemorrhages occur when blood leaks from
the tiny capillaries in the eyes, which can rupture
d...
External Postmortem (PM) picture
1- Petechial hemorrhages
3- Cyanosis
2- Postmortem hypostasis is well-developed
and dark ...
Internal Appearances:.Visceral congestion.
.Petechial hemorrhages: in the visceral pleurae
and pericardium are often known...
Internal Postmortem (PM) picture
• Petechial hemorrhages under the pleura and
pericardium and in the internal organs.
Cong...
Classification of asphyxia

1-Mechanical Asphyxia

2-Toxic Asphyxia

pertaining to force and matter, as
distinguished from...
MECHANICAL ASPHYXIA;














A-Hanging
B-Strangulation; Throttling ;(it is a manual strng)
Mugging
Liga...
•HANGING ;It is violent form of Asphyxial
death caused by suspension of the body by a
ligature around the neck, the constr...
suffocation

 ;smothering ;obstruction to air passages from
outside)nose ,mouth by hand or cloth
 Choking

Obststruction...
Violent Asphyxial Deaths
1- Hanging It is Asphyxial death caused by
suspension of the body by a ligature around the
neck, ...
.Hanging:- suspension of the body by the use of a ligature. It
resembles Ligature strangulation except for the fact that i...
1- Hanging
 It is Asphyxial death caused by suspension of the body by a
ligature around the neck, the constricting force ...
Types of knot
Running noose

Fixed knot
Complete hanging
Incomplete hanging
That form of asphyxial death,
caused
by suspension of body by a ligature round the
neck, constricting force is wt of the b...
Mechanical Asphyxia / Hanging
Mechanism of Death in Hanging
• Asphyxia – anoxic hypoxia
• Reflex cardiac arrest
• Cerebral...
Mechanical Asphyxia / Hanging
AUTOPSY FINDINGS

• Body partly / completely suspended by ligature around the
neck
• Brown l...
Mechanical Asphyxia / Hanging
• Low suspension point – groove less marked,
lower, horizontal
• Typically no classical asph...
Mechanical Asphyxia / Hanging
INTERNAL SIGNS:
 Bruising – occasionally rupture of neck muscles –
sternomastoid
 Bleeding...
Mechanical Asphyxia / Hanging

 Fracture of Hyoid bone – greater cornu at junction
of outer third with inner two thirds e...
Mechanical Asphyxia / Hanging
JUDICIAL HANGING
 Body given a drop of 2 – 4 feet, the noose tightening
and cervical spine ...
Mechanical Asphyxia / Hanging
• Incomplete Suspension
▫ Body not completely suspended – continuous
pressure of ligature ca...










Death is instantaneous usualy but,5-8 minutes
is common fatal period.
Pm appearances;
ext-dribbling of s...
Ml aspects;










1-wether death was due to hanging;
ligature mark is usually found,
2-lig mark e pet hmrge,
...
Is it suicidal, homicidal, or accidental
hanging?
Suicidal: (most common):
• Circumstantial evidence (history of failure)....
Homicidal hanging;

 is suspected ,when knot is tied in the back of
neck,
 mouth is gagged ,
 limbs are tied,
 injurie...
Externally:

• The neck is stretched.
• The face is pale or bluish.
• The rest of the body is cyanosed.
• Saliva may be se...
Ligature mark:

• Shape:
It is a depression at the site of the ligature
• Situation:
Transverse and complete
(if running n...
Ligature mark:
• Shape: as in hanging.
• Situation: At the level of thyroid cartilage or
below.
• Transverse and
• complet...
Mechanical Asphyxia / Hanging
 Almost all hangings are suicidal
 Sudden compression of the neck blocks the blood
vessels...
Strangulation

It is a form of violent asphyxia
 caused by constricting the neck by some means
 other than wt of body.
...
.Strangulation
2- Ligature strangulation
 A violent Asphyxial death caused by constricting
the neck by a ligature.
 Mechanism of death:...
3- Manual strangulation (Throttling)
• caused by constricting the neck by the hand.

• Autopsy appearances:
• Externally:
...
.Throttling:- constriction of the neck by the use of hands.
 Suffocation; this is a form of asph
 ,caused by mechanical obstruction of air
passages,by means other than constriction...
Autopsy appearances:
• Externally:
• The face is either pale or bluish and congested.
The rest of the body is cyanosed.
• ...
4- Smothering:
 Caused by mechanical occlusion of the air
passages from outside (i.e. the mouth and
nostril) by hand or b...
Smothering :
Is blockage of external air passages by (fabric, sheet, solid
material)
Groups of risk are elderly , infants
...
.Smothering:-occlusion of external respiratory openings
5- Choking
• Caused by mechanical occlusion of the air
passage from inside.
Mechanism of death:
Asphyxia: due to either co...
. Choking:- Obstruction to the air passage due to foreign

body impaction.
Accidental: (most common)
May arise from:
• Inhalation of irritant fumes.
• Impaction of foreign material, such as food or...
Choking
Refer to the blockage of the internal air

way( glottis or trachea) by foreign bodies .
Almost Accidental
Death ca...
Café coronary

This is a condition of accidental choking
where a bolus of food produces complete
obstruction of larynx .it...
Mechanical Asphyxia
Medicolegal Aspects
 Mode of death – asphyxia / anoxia / cerebral
congestion / vagal inhibition / fra...
Mechanical Asphyxia / Manner of
Death


Suffocation – accidental / homicidal – plastic bags



Gagging – homicidal



T...
Mechanical Asphyxia / Manner of
Death
 Hanging – almost always suicidal – accidental
 Suspension of body after death to ...
What is a "cafe coronary?
• "Cafe coronary" is poorly named because it has
nothing to do with a heart attack. This conditi...
Choking (Cafe Coronary)
• How does choking occur?
• Choking occurs when a piece of food or some
other object gets stuck in...
What are the symptoms?
• Symptoms of choking may include:
• trouble talking or inability to talk
• high-pitched breathing,...
How does choking occur?
• Choking occurs when a piece of food or some
other object gets stuck in the airway. Chicken,
fish...
What are the symptoms?
• Symptoms of choking may include:
• trouble talking or inability to talk
• high-pitched breathing,...
What are the symptoms?
• Symptoms of choking may include:
• trouble talking or inability to talk
• high-pitched breathing,...
Choking (Cafe Coronary)
• How can I help someone who is choking?
• If someone is choking but still able to breathe
and cou...
Crush asphyxia
traumatic asphyxia or crush asphyxia is
usually used to describe compressive asphyxia
resulting from being...
Pressure on the chest and abdomen
due to:

• Burial in earth following house collapse.
• Crushing by a crowd, as in case o...
Drowning:-This is due to submersion of the respiratory openings under.
.water or any other fluids
It is a form of violent asphyxia in which death results
from submersion of mouth and nostrils of a living person
under wat...
Drowning is...
• Death secondary to asphyxia
while immersed in a liquid,
usually water, or within 24 hours
of submersion
In drowning...
air hunger and usually panic
Reflex inspiratory efforts lead to aspiration of
water and laryngospasm
asphyx...
Asphyxia
Laryngospasm maintained

Relaxation of the airway

Respiratory arrest

Water enters lungs

Cardiac arrest

Surfac...
2- Sure external signs:
A-Froth:
(Fine – White – Odorless _ increase)
B-Cadaveric spasm
of the hands on weeds, mud, sand, ...
Immersion is suffocatioin of mouth
&nostrils in liquid
• goose-skin, or anserina cutis, which is
roughening, or pimpling o...
External appearances
1. Signs of immersion:
These are found in any body found dead in water
(whatever the cause of death)....
Goose skin
Goose
Washerwoman’s hands
Internal appearances
• Voluminous lungs with indentation marks of
ribs on their lateral surfaces.
• Respiratory passages c...
Diatoms: microscopic, unicellular algae, found
• These are
in fresh as well as salt water.
• When a live person is drowned...
The medico-legal (ML) importance of diatoms:
• 1- Sure signs of drowning,
• 2- Could still be identified in putrefied bodi...
In putrefied bodies:
• Only diatoms could be identified
2-Toxic Asphyxia
.Due to intoxication with poisons such as:
.Cyanide.
.Carbon monoxide.
.Organic Phosphate fertilizers.
3-Pathological Asphyxia
Pulmonary Embolism.
Glottic Oedema.
Acute Pulmonary Oedema.
4-Neonatal Asphyxia
Hypoxic hypoxia due to distorted umbilical cord
or uterus spasm.
Asphyxia is Asphyxia
5-Electrical due to

• Convulsions and spasm of respiratory muscles.

•Central due to depression of r...
6-Asphyxia Due To Low Atmospheric
Ambient Anoxic Anoxia.
Oxygen Content
Specially in:
•high altitudes
•Presence of CO2 or ...
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
  Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students
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Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students

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Asphyxia From FME by Dr Yaseen Mohammad for 3rd year MBBS Students

  1. 1. ‫بسم ا الرحمن الرحيم‬
  2. 2. yaseen.muhammad50@face book.com definition conditions stages causes mechanism classification pm findings/ext/internal
  3. 3. Definition: • Conditions in which the supply of oxygen to the blood and tissues has been reduced below the normal working level by any interference with respiration. • Asphyxia is used as being equal to “lack of oxygen” or “hypoxia”,
  4. 4. Definition Any condition that obstruct respiratory passages or interferes with respiratory process resulting in a lowered O2 (hypoxia) and increased CO2 (Hypercapnia).
  5. 5. Mechanical Asphyxia ASPHYXIA • Interference with oxygenation – any where from environment down to cellular level
  6. 6. Mechanical Asphyxia CAUSE S OF ASPHYXIA:  Environmental  Obstruction of external respiratory passages  Obstruction of internal respiratory passages  Restriction of respiratory movements  Lung disease  Deficient oxygen transport
  7. 7. Mechanical Asphyxia MECHANISMS  Environmental  Low or no atmospheric oxygen e.g. ships holds  Scuba diving, surgical anesthesia, disused refrigerators  Suffocation  Smothering  Gagging  Choking
  8. 8. Mechanical Asphyxia  Throttling  Ligature Strangulation  Hanging  Traumatic asphyxia  Sexual asphyxia  Positional asphyxia
  9. 9. Mechanical Asphyxia SUFFOCATION  Obstruction of mouth and nose  Smothering / overlaying / plastic bags TRAUMATIC  Pressure fixation of chest wall & abdomen — burying under debris / vehicle / crowd pressure- stampede/ knee abdomen pressure / scissor technique / prone position /overlaying / anaconda large snakes
  10. 10. Mechanical Asphyxia STRANGULATION  Obstruction of air way at the level of larynx by a ligature directly applied on the neck HANGING  Compression of the neck structures by means of ligature-the pressure applied through suspension of body
  11. 11. Mechanical Asphyxia MECHANISM OF DEATH  Oxygen deprivation  Carbon dioxide accumulation  Reduced blood flow to and from the brain  Vagal stimulation resulting in cardiac inhibition  Complex
  12. 12. Mechanical Asphyxia PATHOLOGICAL CHANGES • General ▫ Cyanosis ▫ Congestion ▫ Engorgement right side heart ▫ Fluidity of blood ▫ Petechial hemorrhages / Tardieus spots
  13. 13. Classify Mechanical Asphyxia; what are specific pathological changes in mech asph, give one point in favour for each type PATHOLOGICAL CHANGES • Specific Evidence of asphyxiating mechanism Bruising of lips / nose(smothering) Finger nail marks on the neck (throttling) Ligature mark on the neck (ligature strangulation) Signs of trauma to chest ( traumatic asph.) Specific – Injuries to the largynx (structures)
  14. 14. Mechanical Asphyxia PATHOLOGICAL CHANGES • Specific – Injuries to the larynx ▫ Hyoid bone ▫ Thyroid cartilages ▫ Cricoid cartilage ▫ Carotid artery ▫ Vagus nerve
  15. 15. Mechanical Asphyxia Sexual / Autoerotic Asphyxia / Autoerotic Deaths  Accidental hangings, failure of safety mechanisms  Male, trasvestism or nudity, masochism, pornographic material  Scene is diagnostic.
  16. 16. Mechanical Asphyxia POSITIONAL ASPHYXIA  Bodily position which obstructs airway or impairs act of breathing  Typically associated with sedative intoxication  Usually accidental (alcoholics)
  17. 17. Mechanical Asphyxia • Environmental asphyxia ▫ Due to lack of oxygen in the environment
  18. 18. Mechanical Asphyxia SUFFOCATION  Obstruction of nose and mouth  Homicidal, soft smothering  "Overlaying"  Plastic bags, suicidal or accidental Difficult diagnosis; history and scene.
  19. 19. Mechanical Asphyxia CHOKING  Obstruction of upper airway or glottis  Gag, homicide, rarely suicide  Accidental in elderly, mental defectives, children  "Cafe Coronary"
  20. 20. Mechanical Asphyxia / Throttling THROTTLING (Manual Strangulation) Form of mechanical asphyxia where neck structures are compressed by hand / hands  Different grips, different patterns  Finger pad bruises, crescent abrasions  Neck muscle haemorrhages - thyroid cartilage fractures  Mugging, bansdola / sleeper hold  Grip for half a minute.
  21. 21. Mechanical Asphyxia / Throttling  General signs of asphyxia  Congestion of face / bleeding from mouth and nose  Evidence of asphyxiating mechanism  Multiple bruises on the neck / finger nail marks, bruises may not be obvious if throttling affected through soft material  Bruising of neck muscles  Rupture of intima carotid artery  Fracture of thyroid cartilage one or both superior horns.  # Hyoid bone is rare because of lower position of grip
  22. 22. Mechanical Asphyxia / Strangulation STRANGULATION  Air way obstruction at larynx from pressure by a ligature / garrotting  Horizontal groove, uniform depth, imprint abrasion, ligature groove may be multiple / knotted  Tied, held, removed – sexual assault
  23. 23. Mechanical Asphyxia / Strangulation  Bruises, abrasions  Neck muscle haemorrhages, thyroid cartilage fractures  Suicide uncommon but possible – tourniquet / accident occasional – children playing / babies falling from cot / female pelion rider – dupatta / burqa entangling in the wheel / chain
  24. 24. Mechanical Asphyxia / Strangulation MECHANISM OF HYOID BONE FRACTURE • Direct compression • Indirect – pull on the thyro hyoid ligament
  25. 25. Asphyxia or asphyxiation • (from Greek α- "without" and sphyxis, "heartbeat") is a condition of severely deficient supply of oxygen to the body that arises from being unable to breathe normally • Asphyxia causes generalized hypoxia, which primarily affects the tissues and organs. • There are many circumstances that can ;induce asphyxia
  26. 26. Asphyxia can cause coma or death  the constriction or obstruction of airways, such as from asthma, laryngospasm, Respiratory diseases     or simple blockage from the presence of foreign materials; from being in environments where oxygen is not readily accessible: Exposure to extreme low pressure such as underwater, in a low oxygen atmosphere, or in a vacuum; environments where sufficiently oxygenated air is present, but cannot be adequately breathed because of air contamination such as excessive smoke..
  27. 27. Other causes of oxygen deficiency include Carbon monoxide inhalation, such as from a car exhaust: carbon monoxide has a higher affinity than oxygen to the hemoglobin in the blood's red blood corpuscles, bonding with it tenaciously,  Contact with certain chemicals, including pulmonary agents (such as phosgene) and blood agents (such as hydrogen cyanide)  Drug overdose  Sleep apnea
  28. 28. • • • • • Ondine's curse, central alveolar hypoventilation syndrome Acute respiratory distress syndrome. Hanging Drowning
  29. 29. Ondine's curse  , also called congenital central hypoventilation syndrome (CCHS) or primary alveolar hypoventilation, is a respiratory disorder that is fatal if untreated. Persons afflicted with Ondine's curse classically suffer from respiratory arrest during sleep.  CCHS is congenital or  developed due to severe neurological trauma to the brainstem
  30. 30. Stages of asphyxia 1- Stage of dyspnea: . 2- Stage of convulsions: . 3-Stage of apnea (respiratory paralysis The respiratory center (RC) is located in the medulla oblongata, which is the lowermost part of the brain stem The groups of nerve cells in the brain which regulates the respiration rhythmically are collectively known as respiratory centers
  31. 31. Respiratory centre is divided four major groups • Inspiratory centre (Dorsal respiratory group) • Location: Dorsal portion of medulla • Nucleus: Nucleus tractus solitarius • Function: causes inspiration while stimulated.
  32. 32. Expiratory centre (Ventral respiratory group)  Location: Antero- lateral part of medulla, about 5 mm anterior and lateral to dorsal respiratory group  Nucleus: Nucleus ambiguous and nucleus retro ambiguous.  Function: It generally causes expiration but can causes either expiration or inspiration depending upon which neuron in the group are stimulated. It sends inhibitory impulse to the apneustic centre.
  33. 33. Pneumotaxic centre         Location: Pons(upper part ) Nucleus: Nucleus parabrachialis Function: It controls both rate and pattern of breathing. Limit inspiration. Apneustic centre Location: Pons(lower part) Function: a)It discharges stimulatory impulse to the inspiratory centre causing inspiration. b)It receives inhibitory impulse from pneumotaxic centre and from stretch receptor of lung. c)It discharges inhibitory impulse to expiratory centre.
  34. 34. Respiratory center depression • Depression of a respiratory center can be a result of next reasons: • medical drug action (opioids, sedatives and etc.) • sudden cessation of blood circulation in brain • heavy brain trauma • sharp neuroinfections • brain tumors • damage of a brainstem
  35. 35. A convulsion is a medical condition where body muscles contract and relax ] .rapidly and repeatedly, resulting in an uncontrolled shaking of the body The pattern repeats, with each cycle usually taking 30 seconds to 2 minutes. It is an oscillation ( periodic variation )of ventilation between apnea and hyperpnoea
  36. 36. General Post Mortem Appearance External Appearances:.Face: oedematous and congested. .Eye: proptosis due to retro-orbital oedema. .Deep cyanosis: especially in nails and lips. .Lividity appears early and is well formed. hial hemorrhages: in the skin and eyes articularly the eyelids, conjunctiva, sclera, face, ps and behind the ears).
  37. 37. Petechial Hemorrhage Sites of formation: in the skin and eyes , particularly the eyelids, conjunctiva, sclera, face ) lips and behind the ears • A petechial hemorrhage is a tiny pinpoint red mark that is an important sign of asphyxia caused by some external means of obstructing the airways. They are sometimes also called petechiae. Their presence often indicates a death by manual strangulation, hanging, or smothering.
  38. 38. Mechanism of formation • The hemorrhages occur when blood leaks from the tiny capillaries in the eyes, which can rupture due to increased pressure on the veins when the airways are obstructed. • If petechial hemorrhages and facial congestion are present, it is a strong indication of asphyxia by strangulation as the cause of death.
  39. 39. External Postmortem (PM) picture 1- Petechial hemorrhages 3- Cyanosis 2- Postmortem hypostasis is well-developed and dark in color 4- Rigor mortis is rapid 5- Putrefaction is rapid.
  40. 40. Internal Appearances:.Visceral congestion. .Petechial hemorrhages: in the visceral pleurae and pericardium are often known as "Tardieu's spots". Tardieu's spots ; spots of ecchymosis under the pleura after death Dark::Blood. due to the large amount of reduced hemoglobin. Fluid:- release of fibrinolysin shortly after death.
  41. 41. Internal Postmortem (PM) picture • Petechial hemorrhages under the pleura and pericardium and in the internal organs. Congestion and edema of the viscera • The blood is dark in color and more fluidly. • The right heart and great veins are engorged with blood.
  42. 42. Classification of asphyxia 1-Mechanical Asphyxia 2-Toxic Asphyxia pertaining to force and matter, as distinguished from mental, vital, chemical, .etc 3-Pathological Asphyxia 4-Neonatal Asphyxia ectrical Asphyxia-5 phyxia Due To Low Atmospheric Oxygen Conten
  43. 43. MECHANICAL ASPHYXIA;              A-Hanging B-Strangulation; Throttling ;(it is a manual strng) Mugging Ligature Bansdola ;a form of strangulation where the neck is compressed in between two bamboo or other sticks, one in front and the other behind Garroting A garrote (a Spanish word; is a weapon, referring to a handheld ligature of chain, rope, scarf, wire used to strangle a person Suffocation'sSmothering Choking Gagging drowning Traumatic asphyxia -D
  44. 44. •HANGING ;It is violent form of Asphyxial death caused by suspension of the body by a ligature around the neck, the constricting force being the weight of the body. Lynching; is a condition where several persons acting jointly overpower an individual &hang him by rope Strangulation • It is a form of violent asphyxia • caused by constricting the neck by some mean ,other than wt of body throttling ,mugging ,bansdola Garroting .are types of strang ...
  45. 45. suffocation  ;smothering ;obstruction to air passages from outside)nose ,mouth by hand or cloth  Choking Obststruction from inside by solid object( foreign body) results reflex spasm , death is due to vagal inhibition or laryngeal spasm Drowning It is a form of violent asphyxia in which death results from submersion of mouth and nostrils of a living person under water traumatic asphyxia or crush asphyxia is usually used to describe compressive asphyxia resulting from being crushed or pinned under a large weight or force
  46. 46. Violent Asphyxial Deaths 1- Hanging It is Asphyxial death caused by suspension of the body by a ligature around the neck, the constricting force being the weight of the body. 2- Ligature strangulation A violent Asphyxial death caused by constricting the neck by a ligature 3- Manual strangulation (Throttling) 4- Smothering: 5- Choking 6- Traumatic asphyxia (Crush asphyxia)
  47. 47. .Hanging:- suspension of the body by the use of a ligature. It resembles Ligature strangulation except for the fact that in hanging the constriction Force being the weight of the body and the force of gravity as well.
  48. 48. 1- Hanging  It is Asphyxial death caused by suspension of the body by a ligature around the neck, the constricting force being the weight of the body. A) It may be either complete or partial: on the basis of degree of suspension B) It may be either typical or atypical: on the basis of position of knot Complete ; when wt of the body acts as constricting force Incomplete; when part of the body act as constricting force Typical; Knot at the occipit Atypical; Knot at any site other than the occipit
  49. 49. Types of knot Running noose Fixed knot
  50. 50. Complete hanging
  51. 51. Incomplete hanging
  52. 52. That form of asphyxial death, caused by suspension of body by a ligature round the neck, constricting force is wt of the body. . hanging Cause of death 1-asphyxia due to blocking of air passages, by ligature.  2-cerebral congestion due to compression of jugular veins(congestive hypoxia) 3 -pressure on carotid arteries, obstruction of arterial blood, thus cerebral anoxia &coma. 4-vagal shock from compression of trigger area. 5 -injury to spinal cord as in judicial hanging.
  53. 53. Mechanical Asphyxia / Hanging Mechanism of Death in Hanging • Asphyxia – anoxic hypoxia • Reflex cardiac arrest • Cerebral anoxia • Cerebral congestion • Fracture dislocation cervical vertebrae
  54. 54. Mechanical Asphyxia / Hanging AUTOPSY FINDINGS • Body partly / completely suspended by ligature around the neck • Brown leathery ligature furrow, imprint abrasion • Fixed noose-inverted v-shape, knot mark • Running noose – horizontal
  55. 55. Mechanical Asphyxia / Hanging • Low suspension point – groove less marked, lower, horizontal • Typically no classical asphyxial features • Scene shows preparation and precautions
  56. 56. Mechanical Asphyxia / Hanging INTERNAL SIGNS:  Bruising – occasionally rupture of neck muscles – sternomastoid  Bleeding between pharynx and spine  Injury to carotid arteries with bleeding in the walls or horizontal breech of the intima at the level of ligature
  57. 57. Mechanical Asphyxia / Hanging  Fracture of Hyoid bone – greater cornu at junction of outer third with inner two thirds esp. after age 40  Fracture thyroid cartilage – great horn/s  Fractures of Hyoid and thyroid may occur alone or together – may not occur in low suspensions
  58. 58. Mechanical Asphyxia / Hanging JUDICIAL HANGING  Body given a drop of 2 – 4 feet, the noose tightening and cervical spine receiving a jerk – dislocation and fracture at 3rd and 4th or 2nd and 3rd cervical vertebrae severing the upper part of spinal cord – instantaneous death , heart may continue to beat for a few minutes
  59. 59. Mechanical Asphyxia / Hanging • Incomplete Suspension ▫ Body not completely suspended – continuous pressure of ligature causes asphyxia
  60. 60.         Death is instantaneous usualy but,5-8 minutes is common fatal period. Pm appearances; ext-dribbling of saliva due to stimulation of salivary glands by ligature is a vital sign, indicating that victim was alive at the time of suspension. Ligature mark on the neck; in complete hanging mark is situated over the level of thyroid cartilage b/w larynx&chin.seen in front, sides of neck. Lig knot may form a fixed or running noose Internal appearance; local injury ,spinal cord inj
  61. 61. Ml aspects;          1-wether death was due to hanging; ligature mark is usually found, 2-lig mark e pet hmrge, dribble saliva, carotid art tear, absence of fatal inj &poisoning. Suicidal hang; it is common in men, there is no signs of struggle, farewell note will be present.
  62. 62. Is it suicidal, homicidal, or accidental hanging? Suicidal: (most common): • Circumstantial evidence (history of failure). • Absence of signs of struggle. • Presence of signs of previous suicidal attempts. • Suicidal note
  63. 63. Homicidal hanging;  is suspected ,when knot is tied in the back of neck,  mouth is gagged ,  limbs are tied,  injuries on body,  signs of struggle are present.  Lynching; is a condition where several persons acting jointly overpower an individual &hang him by rope.  Sexual asph (auto erotic hanging) also described.
  64. 64. Externally: • The neck is stretched. • The face is pale or bluish. • The rest of the body is cyanosed. • Saliva may be seen dripping from the mouth (It is a vital sign and is present only in hanging but not in postmortem suspension).
  65. 65. Ligature mark: • Shape: It is a depression at the site of the ligature • Situation: Transverse and complete (if running noose). • The pattern of the ligature: Is imprinted on the neck as a pressure abrasion.
  66. 66. Ligature mark: • Shape: as in hanging. • Situation: At the level of thyroid cartilage or below. • Transverse and • complete (this is the usual).
  67. 67. Mechanical Asphyxia / Hanging  Almost all hangings are suicidal  Sudden compression of the neck blocks the blood vessels disrupting blood supply to and from the brain  Usual point of suspension is the side of the neck (typical hanging) followed by back and front (atypical hanging)
  68. 68. Strangulation It is a form of violent asphyxia  caused by constricting the neck by some means  other than wt of body. The means used may be ;ligature,  hand((throttling) , elbow(mugging)or  stick(bansdola) Strangulation should be assumed to be homicidal, until contrary is proved Mugging; strangulation by compression neck again forearm garroting; strng by grasping the throat , throwing a over neck. Throttling ;it is a manual strng
  69. 69. .Strangulation
  70. 70. 2- Ligature strangulation  A violent Asphyxial death caused by constricting the neck by a ligature.  Mechanism of death:  Asphyxia: from compression of air passage  Cerebral congestion or apoplexy:  Reflex vagal inhibition  Cerebral anoxia:  Combination of any of the above
  71. 71. 3- Manual strangulation (Throttling) • caused by constricting the neck by the hand. • Autopsy appearances: • Externally: • Injuries on the neck: • Abrasions (caused by finger nails). • Contusions (caused by finger pads).
  72. 72. .Throttling:- constriction of the neck by the use of hands.
  73. 73.  Suffocation; this is a form of asph  ,caused by mechanical obstruction of air passages,by means other than constriction of neck  It includes ;  smothering (obstruction to air passages from outside)nose ,mouth by hand or cloth.  Choking  ;obstr from inside by solid object( foreign body) results reflex spasm , death is due to vag inhibition or laryngeal spasm.  Drowning; submersion of mouth&nostrils under water  Traumatic asph;obst to resp movements
  74. 74. Autopsy appearances: • Externally: • The face is either pale or bluish and congested. The rest of the body is cyanosed. • The tongue may be protruded, swollen and bitten. • Bleeding from ears and nose may be seen.
  75. 75. 4- Smothering:  Caused by mechanical occlusion of the air passages from outside (i.e. the mouth and nostril) by hand or by any object.  PM picture  Asphyxial signs will be present except in case of plastic bag suffocation.  Abrasions and contusions on the skin of the face around mouth and nose (Absent if a soft material, such as a pillow, is used).
  76. 76. Smothering : Is blockage of external air passages by (fabric, sheet, solid material) Groups of risk are elderly , infants A part from classical signs of asphyxia such as petechiea may appear and there is usually a lack of objective finding. Plastic bag suffocation can be rapid and symptomless depending on how it is done. The death in plastic bag facial occlusion is some rapid cardio inhibitory mode rather than purely hypoxic process.
  77. 77. .Smothering:-occlusion of external respiratory openings
  78. 78. 5- Choking • Caused by mechanical occlusion of the air passage from inside. Mechanism of death: Asphyxia: due to either complete occlusion of air passage, or partial occlusion that is completed by spasm, edema and mucus secretion.
  79. 79. . Choking:- Obstruction to the air passage due to foreign body impaction.
  80. 80. Accidental: (most common) May arise from: • Inhalation of irritant fumes. • Impaction of foreign material, such as food or denture. • Inhalation of dust and sand in falling of houses. • Inhalation of vomit or blood during operations. • Falling back of the tongue epileptic fit.
  81. 81. Choking Refer to the blockage of the internal air way( glottis or trachea) by foreign bodies . Almost Accidental Death can be of purely hypoxic origin from occlusion of airway with characteristic signs of congestion , cyanosis & petechiae. The groups most at risk are : Children, old people, mentally disorder, drunk,Greedy Eaters ,Drugged
  82. 82. Café coronary This is a condition of accidental choking where a bolus of food produces complete obstruction of larynx .it is so called b.c it mimics heart attack .it may be d/t Suppressed gag reflex – alcoholics, drug intoxicated Reflex cardiac arrest; due to stimulation of laryngeal nerve The victim who was healthy apparantly collapses & suddenly turns blue while eating
  83. 83. Mechanical Asphyxia Medicolegal Aspects  Mode of death – asphyxia / anoxia / cerebral congestion / vagal inhibition / fracture dislocation cervical vertebrae  Cause of death – suffocation / throttling / strangulation / hanging / drowning  Manner of death – suicidal / homicidal / accidental
  84. 84. Mechanical Asphyxia / Manner of Death  Suffocation – accidental / homicidal – plastic bags  Gagging – homicidal  Throttling – homicidal  Strangulation – homicidal – accidental esp. children
  85. 85. Mechanical Asphyxia / Manner of Death  Hanging – almost always suicidal – accidental  Suspension of body after death to simulate suicidal hanging – circumstances / scene / locus examination  Evidence of other cause of death  Sexual asphyxias – accidental
  86. 86. What is a "cafe coronary? • "Cafe coronary" is poorly named because it has nothing to do with a heart attack. This condition got its name because onlookers may think they are witnessing a heart attack when a diner is really choking to death. "Cafe coronary" is blockage in the upper airway, usually caused by food or vomit stuck in the throat. The blockage causes choking and makes it hard to breathe. It can be life threatening.
  87. 87. Choking (Cafe Coronary) • How does choking occur? • Choking occurs when a piece of food or some other object gets stuck in the airway. Chicken, fish bones, and pieces of meat that have not been chewed properly get stuck in the throat easily. If you have been drinking alcohol, your risk of choking is greater because you may be careless about chewing food well.
  88. 88. What are the symptoms? • Symptoms of choking may include: • trouble talking or inability to talk • high-pitched breathing, wheezing, or not breathing at all • forceful coughing or inability to cough • clutching the throat or chest as a sign of distress • fainting.
  89. 89. How does choking occur? • Choking occurs when a piece of food or some other object gets stuck in the airway. Chicken, fish bones, and pieces of meat that have not been chewed properly get stuck in the throat easily. If you have been drinking alcohol, your risk of choking is greater because you may be careless about chewing food well.
  90. 90. What are the symptoms? • Symptoms of choking may include: • trouble talking or inability to talk • high-pitched breathing, wheezing, or not breathing at all • forceful coughing or inability to cough • clutching the throat or chest as a sign of distress • fainting.
  91. 91. What are the symptoms? • Symptoms of choking may include: • trouble talking or inability to talk • high-pitched breathing, wheezing, or not breathing at all • forceful coughing or inability to cough • clutching the throat or chest as a sign of distress • fainting.
  92. 92. Choking (Cafe Coronary) • How can I help someone who is choking? • If someone is choking but still able to breathe and cough and is not turning a bluish color, let them try to cough up the object. If they are having trouble breathing and turning blue, have someone call while you do the following to help: • Ask the person if they are choking. If they cannot answer you, or they grab their throat, they need help right away. • Give 5 back blows. ▫ Stand behind the person and wrap one arm around their chest.
  93. 93. Crush asphyxia traumatic asphyxia or crush asphyxia is usually used to describe compressive asphyxia resulting from being crushed or pinned under a large weight or force Ex.. collapsing trenches, panic in crowds,  car-jack while repairing from below, even anacondas(monstor snake) and pythons(ajdaha)  These case tend to exhibit gross congestion,cyanosis,and petechiae of the face, neck and shoulder with bleeding from the ear and the nose
  94. 94. Pressure on the chest and abdomen due to: • Burial in earth following house collapse. • Crushing by a crowd, as in case of a fire.
  95. 95. Drowning:-This is due to submersion of the respiratory openings under. .water or any other fluids
  96. 96. 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).
  97. 97. Drowning is... • Death secondary to asphyxia while immersed in a liquid, usually water, or within 24 hours of submersion
  98. 98. In drowning... air hunger and usually panic Reflex inspiratory efforts lead to aspiration of water and laryngospasm asphyxia and hypoxaemia / acidosis
  99. 99. Asphyxia Laryngospasm maintained Relaxation of the airway Respiratory arrest Water enters lungs Cardiac arrest Surfactant washout “Dry drowning” “Wet drowning” mechanism in fresh and salt water slightly* different
  100. 100. 2- Sure external signs: A-Froth: (Fine – White – Odorless _ increase) B-Cadaveric spasm of the hands on weeds, mud, sand, etc.
  101. 101. Immersion is suffocatioin of mouth &nostrils in liquid • goose-skin, or anserina cutis, which is roughening, or pimpling of the skin, skin maceration, or washer-woman's skin, which is swelling and wrinkling of the skin, and adipocere, which is the transformation of the fatty layer beneath the skin into a soap-like material - a process requiring many weeks or months
  102. 102. External appearances 1. 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
  103. 103. Goose skin
  104. 104. Goose
  105. 105. Washerwoman’s hands
  106. 106. 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),
  107. 107. Diatoms: microscopic, unicellular algae, found • These are 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.
  108. 108. 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).
  109. 109. In putrefied bodies: • Only diatoms could be identified
  110. 110. 2-Toxic Asphyxia .Due to intoxication with poisons such as: .Cyanide. .Carbon monoxide. .Organic Phosphate fertilizers.
  111. 111. 3-Pathological Asphyxia Pulmonary Embolism. Glottic Oedema. Acute Pulmonary Oedema.
  112. 112. 4-Neonatal Asphyxia Hypoxic hypoxia due to distorted umbilical cord or uterus spasm.
  113. 113. Asphyxia is Asphyxia 5-Electrical due to • Convulsions and spasm of respiratory muscles. •Central due to depression of respiratory center.
  114. 114. 6-Asphyxia Due To Low Atmospheric Ambient Anoxic Anoxia. Oxygen Content Specially in: •high altitudes •Presence of CO2 or N2

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