CHAPTER 11
ASPHYXIA
Chapter 11 : ASPHYXIA
Ass. Prof.Dr. Atef Foda & Dr. Eslam Samy
ASPHYXIA
The term asphyxia (from Greek, “a” = without & “sphuxis"= pulse or heartbeat). It
refers to a state in which the body becomes deprived of oxygen while in excess of
carbon dioxide (i.e. hypoxia and hypercapnoea) without a steady supply of oxygen,
the body's vital functions shutdown within four to six minutes.
Hypoxia: means that O2 lack in the tissues.
Anoxia: means that no O2 is present in the tissues.
Stages of asphyxia:
It is usual to divide the effects of asphyxia into four stages:
1. Stage of inspiratory dyspnoea: in which there is deep and forceful respiration,
with congestion and cyanosis.
2. Stage of expiratory dyspnoea: in which there is spasmodic efforts at expiration,
the consciousness is lost, pupils are dilated and the blood pressure is raised, with
petechiae.
3. Third stage: there is fall of blood pressure, pulse is increased and spontaneous
defecation occurs. Erection of the penis and ejaculation of semen may occur.
4. Terminal stage: respiratory movements cease except for terminal irregular
occasional respiration, heart continues to beat for 10 – 15 minutes.
Types of asphyxia:
1. Pathological: as in cases of diphtheria, tumors in air passages, edema of the glottis
and poliomyelitis.
2. Toxicological: as in cases of morphine poisoning (depression of respiratory center),
strychnine poisoning (spasm of respiratory muscles), and parathion poisoning
(paralysis of respiratory muscles); CO, hydrogen cyanide, and hydrogen sulphide
poisoning (chemical asphyxia).
3. Violent asphyxia (Mechanical asphyxia):
It is due to mechanical interferences to respiration by (a) Impedes access of air to
lungs, or (b) Reduces blood supply to head and neck, or (c) Causes sudden cardiac
arrest due to stimulation of carotid sinus with resulting reflex vagal inhibition. Violent
asphyxia occurs in cases of:
I. Suffocation (smothering, choking, traumatic asphyxia, etc.).
II. Fatal pressure on the neck (hanging and strangulation).
III. Drowning.
Classical signs of asphyxia (P.M. picture):
The classical signs of asphyxia are accentuated where there is struggle to breath due to
obstruction of the air passages or pressure on the neck or chest.
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Conversely, cardiac arrest may occur either immediately or after a short interval of
pressure on the neck, or sudden blockage of the air passage, or sudden entry into
irrespirable gas, so the classical signs of asphyxia may have no time to develop.
So, the classical signs of asphyxia are nonspecific and can occur in deaths from other
causes, they should never be accepted alone as an evidence of asphyxia.
(A) External signs:
1. Congestion of the face: is the red appearance of the skin of the face and head.
It is due to the filling of the venous system when compression of the neck
prevents venous return to the heart.
2. Edema of the face: is the swelling of the tissues due to transudation of fluid
from the veins caused by the increased venous pressure as a result of venous
obstruction of venous return to the heart
3. Cyanosis of the skin (especially head & neck): is the blue color due to the
presence of deoxygenated blood in the congested venous system.
4. Petechial haemorrhages: are pinpoint haemorrhages, most commonly seen in
the skin of the head and face and especially in the lax tissues: lips, behind the
ear, eyelids, conjunctivae and sclera of the eyes. This is duo to marked increase
in venous pressure from impaired venous return (causes rupture of small
venules), and hypoxia of the vessel wall.
5. The eye ball appear prominent due to retro – orbital oedema and congestion
6. Hypostasis is well developed and is dark blue in color.
7. Bloody forth appears around mouth and nose due to rupture of the capillaries
in the air passage.
(B) Internal Signs:
1. Congestion: Visceral congestion is due to capillo–venous congestion as a result
of susceptibility of capillaries to hypoxia. This leads to dilatation of capillaries
with stasis of blood in the dilated capillaries and venules.
2. Pulmonary edema and pulmonary haemorrhage:
It is common in many modes of death. It has little value in diagnosis of death
due to respiratory obstruction.
3. Petechial haemorrahages: on the pleural surface of the lung, the epicardium,
and thymus in children (true Tardieu spots). It can also appear any where e.g. in
the brain &its meninges, the lungs, the heart, etc.
4. Silvery spots: shining grey spots under the pleura can be seen by a hand lens,
duo to increased intra thoracic –ve pressure with rupture of superficial
unsupported alveoli.
NB: -Description of abnormal blood fluidity seen at autopsy of asphyxial
deaths is a part of forensic mythology.
-Engorgement of right side of the heart and great veins is also a nonspecific autopsy observation.
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(I) Suffocation
Asphyxial deaths other than fatal pressure on the neck and drowning result from
failure of oxygen to reach the blood, either duo to:
a. Absence or reduction in the O2 content of the inspired air.
b. Mechanical obstruction of the external respiratory orifices or the upper air
passages from without or within.
The following types of suffocation are usually seen:
1-Environmental suffocation 2- Smothering
3- Chocking
4- Gagging
5- café – coronary
6- Traumatic asphyxia
7- Positional asphyxia 8- Burking & Overlaying
1- Environmental suffocation
Asphyxia is caused by inadequate oxygen in the environment, which may be duo to:
a. Actual reduction of O2: such as might occur in:
-The deep tanks of ships (rust formation).
-In an underground closed chamber (fungus growth).
-Entrapment in an air tight enclosure (a child trapped in a box or a
discarded refrigerator).
b. Suffocating gases: deaths are caused by displacement of O2 from the
atmosphere by these gases. The most common suffocating gases are CO2
& methane, both are nontoxic and odorless.
- CO2 is found in dry wells, farm silos & mines.
- Methane (94-95) is the principle constituent of natural gas that is used
for cocking.
Manner of death:
. Usually accidental in nature.
. Suicidal & homicidal are rare, but do occur, especially from suffocating
gases.
Mechanism of death:
Reduction of atmospheric oxygen to less than 25% of normal concentration leads to
hypoxia & unconsciousness in seconds and death in minutes.
P.M. diagnosis:
. Analysis of the circumstances of death.
. Autopsy:
- No specific autopsy findings, only nonspecific visceral congestion.
- Toxicological analysis of blood is of no help in case CO2, as it is
a normal constituent of blood. Methane can be detected in the blood.
. Exclusion of other causes of death.
2- Smothering
It is a form of violent asphyxia resulting from mechanical occlusion of the mouth and
nose that prevent breathing. The smothering agent is usually a fabric, an impervious
sheet, plastic bag or a hand and occasionally a mobile solid such as sand, mud, grain
or flour may be responsible
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Manner of death:
1. Suicidal smothering:
- Can occur by using a plastic bag placed over the head down to neck level.
2. Accidental Smothering:
It occurs in the following conditions:
o The bedclothes cover the nostrils and month of the infants during first month of
life especially premature.
o When an infant turns on its face in its cot and buries this face in a soft pillow or
mattress.
o Smothering may occur in epileptics or persons comatose from drink or drug
that fall face down into soft pillow, mud, or thick grass.
o In children during playing with plastic bag.
3. Homicidal Smothering:
o It is a common mode of infanticide, sexual assault, and kidnapping.
o The victim is usually an infants, young child or debilitated person where there
is a gross disparity between the assailant and the victim.
o Usually mouth and nostrils are closed by mean of hand, a soft subject or even a
plaster.
Postmortem Picture:
a) External Findings:
1. No external signs when the obstruction is by soft material such as bed clothing,
pillow or mother's breast. Also, in cases of suicide with plastic bag.
2. There are scratch abrasions, bruises, finger nail marks, laceration of victim's
lips, and may be broken teeth in cases of homicides by hand smothering.
3. In cases of a homicide by gagging (a sub type of smothering), it is the discovery
of the gag obstructing the airways that makes the diagnosis.
b) Internal Findings:
Internal classical signs of asphyxia.
3- Gagging
This is a type of asphyxia in which a cloth is forced into the mouth, or the mouth and
nose may be closed by tying a cloth or a similar material around them. This rolled up
cloth is a called a gag. Usually the gag is inserted to prevent the victim from shouting
but death occurs unintentionally.
Mechanism of death:
At first, breathing can take place via nose, but as time goes on, nasal mucus, saliva
combine with nasal and pharyngeal edema to cause obstruction and progressive
suffocation develops.
Manner of death:
This is almost always homicidal and is commonly employed in children. In adults the
hands are tied at the back as well as legs are tied to prevent them from removing the
gag or walking and running for help.
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4-Choking
It is a form of suffocation caused by an obstruction of the internal air passage between
the hypo pharynx and the bifurcation of the trachea.
Manner of death:
(A) Accidental:
1. Inhalation of foreign body into the glottis such as bolus of meat, button, coins,
pins or artificial dentures.
2. Aspiration of vomited material in an unconscious, as in during anesthesia,
epileptic fits, and acute alcoholism.
(B) Pathological:
1. Inhalation of products of disease such as blood or pus.
2. Anatomical changes due to disease such as fulminating epiglottitis, laryngeal
edema, laryngeal tumors.
3. Diphtheritic membrane and angioneurotic edema of the glottis.
(C) Homicidal:
It is rare and may occur in:
1. In infants, by packing the infant's pharynx with a piece of cotton or cloth.
2. In adult where cloth or soft object is pushed into the mouth to silence the
individual (gagging leads to choking).
(D) Suicidal:
It is rare but may be seen in mentally ill patients who do not have access to other
methods of committing suicide.
Mechanism of death:
-Severe respiratory distress with progressive hypoxia up to death.
-Vasovagal cardiac arrest with rapid silent death (Caf’e coronary).
Postmortem picture (P.M.P):
a) Analysis of the circumstances surrounding death:
Especially if the obstructing object was removed.
b) External findings:
Are those of asphyxia if it is the cause of death.
c) Internal findings:
1. Presence of impacted foreign body in the air passages.
2. Presence of bruises and abrasions at the site of obstruction.
3. Regurgitated food particles such as vomits, milk etc. may be found mixed with
mucus in trachea, bronchi and lower bronchioles.
4. Tongue should be examined for its position where it is forced back against the
posterior pharyngeal wall as in epilepsy. Also, bruises or bite marks may be present.
5. All organs are congested and other classical signs of asphyxia may be present.
NB: The presence of small amounts of food or vomits in the airway at autopsy does
not indicate that the individual choked to death. This can be an agonal phenomenon at
the time of death or even a postmortem artifact, due to moving the body after death.
Death can be attributed to choking by aspiration only if the airway from larynx down
is completely occluded by food or vomits.
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5- CAFÉ – Coronary
A rapid silent death, where a healthy person suddenly collapses and dies during a
meal, with no signs of respiratory distress or any of the classic signs of asphyxia.
Death initially thought to be coronary heart attack.
Café coronary is chocking by a bolus of food (food aspiration), coins, small stones
and rubber balloons may also accidently aspirated by children, leading to complete
obstruction of the larynx. The mechanism of death is cardiac arrest duo to reflex vagal
inhibition by sudden stimulation of extremely sensitive laryngeal mucosa.
Postmortem picture:
- No classic signs of asphyxia.
- Autopsy revealed a bolus of food, lodged in the hypo pharynx or larynx.
6- Traumatic (crush) asphyxia
This is a type of asphyxia, caused by mechanical fixation of the chest so that normal
movements of respiration wall are prevented.
On other words it occurs by pressure over the chest and abdomen that restricts
respiratory movements.
Manner of death:
1. Accidental:
a) Occurs while repairing a car, the jack slips and the vehicles falls on top of the
individual.
b) In cases like multiple deaths during stampede (‫(فرار جماعي‬, chest is compressed and
respiratory movements prevented by stampeding people pilling on the top of each other
causing “Riot crush” or "human pile" deaths. This occurs in riots and in hotel fire.
c) In building collapse and earthquakes.
2. Homicidal:
It is rarely homicidal. But it may occur by burial of or sitting on the chest of the
victim (torture).
Postmortem picture:
1. It provides the most extreme demonstration of the classic signs of asphyxia.
2. There is deep red or purplish black discoloration of the skin of head,
neck and upper trunk with numerous petechae and ecchymoses.
3. Petechiae of sclera, conjunctiva and retinal haemorrhages.
4. There is intense cyanosis above the level of compression; below the
compression the skin is pale.
5. Internally, haemorrhage is seen in the tissues around the site of compression,
fracture of ribs may be present.
7- Positional Asphyxia
It is also known as postural asphyxia, where a person remains in a certain position for
an extended time, either duo to being trapped, or it is associated with alcohol or drug
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intoxication. This position will lead to mechanical interference to adequate respiratory
movements, and normal venous return to the heart.
One example of positional asphyxia is inversion, either of the whole body or of the
upper half. The manner is usually accidental, but torture by inverted crucifixion may
also lead to death by positional asphyxia. At autopsy, there is marked congestion,
cyanosis and petechiae at the upper dependent half of the body.
8- Overlaying
- This accidental form of suffocation is a combination of mechanical
asphyxia and smothering.
- It is seen most commonly when an infant is put to bed with one or more
adults.
- During night, one of the adult rolls over or otherwise crushes and
asphyxiates the infant by compressing the chest thus preventing respiratory
movements and occluding the nose and mouth with bedding or the body of
the adult. The next morning the child is found dead, may be without any
evidence of trauma.
- The history of an adult sleeping with the child is important to differentiate
such deaths from the cot death.
- In England, it is a criminal offence to share bed by a person of the age of
sixteen years or more with infant.
Autopsy findings:
1. Presence of petechial haemorrhages beneath the conjunctiva, epicardium and
pleura.
2. Evidence of contact flattening of face and nose may or may not be there.
3. Blood tinged froth from mouth and nostrils that may stain the bed clothing.
4. Absence of injury marks over the body.
9- Burking
-This is a form of mechanical asphyxia plus smothering that is homicidal in nature.
- Burke and Hare were murderers during the 1820s in Edinburgh who supplied dead
bodies for anatomical dissection to the medical schools.
- According to Hare, Burke would kneel or sit on the chest, covering the mouth and
nostrils with his hand thus producing a combination of traumatic asphyxia and
smothering.
P.M.P :
- External injury usually absent.
-Classical signs of asphyxia are present but non specific.
Fatal pressure on the neck
Two forms are of forensic importance, hanging and strangulation.
Strangulation is either manual strangulation (throttling), or ligature strangulation.
Mechanism of death:
Rapid or instantaneous death:
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By sudden cardiac arrest, duo to reflex vagal inhibition, by stimulation of baroceptor
nerve endings, in the carotid sinuses and sheaths.
Very often in hanging, common in manual, and less often in ligature strangulation.
Relatively slow death: duo to:
a) Cerebral anoxia: by compression and occlusion of carotid arteries.
b) Closure of the airway by elevation of the larynx against the base of the tongue.
(1) Hanging
Hanging is a form of asphyxial death, which is caused by the suspension of the body
by a ligature, the constricting force being the weight of the body.
Types of hanging:
1. Complete hanging:
In this type of hanging the constricting force is the weight of the body as the body is
fully suspended in air.
2. Incomplete (partial) hanging:
In this type of hanging, the constricting force is the weight of the head (about 5-6kg)
and the lower parts of the body (toes, feet, knees or buttocks) touch the ground.
3. Typical hanging:
The point of suspension is at back of the neck.
4. Atypical hanging:
The point of suspension is at the side or the front of the neck.
Manner of the death:
Hanging can be suicidal, homicidal, accidental and judicial.
1. Suicidal hanging:
- Suicide is the most common mode of hanging.
- The person finds it as one of the easiest, painless and surest methods of death.
Hanging is either the second or third most common method of suicide.
- At the scene of hanging, suicide note may be found, the room is locked from inside
and a chair is usually used to reach the rope.
- There is a history of financial troubles, depressive illness and presence of other
means of suicide (i.e. previous attempts).
2. Accidental hanging:
-Uncommon but sometimes occurs.
-Boys playing in gardens while jumping from trees, get their clothing caught in the
branches and are accidentally hanged.
-Workmen falling from scaffolding have been hanged by becoming entangled in the rope.
3. Homicidal hanging:
-It is very rare.
-It can be a possibility in cases where the victim is a child, an unconscious person or a
very frail (‫واهن‬،‫( ضعيف‬person unable to defend himself. Also, it can be done under the
influence of drugs or alcohol.
-It is suspected in a victim when the knot is tied on the back of the neck, the mouth is
gagged and presence of signs of struggle.
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-A complete toxicological screen should be performed and circumstantial evidence is
of value in these cases.
4. Judicial hanging:
It is the term used when convicted criminals are hanged.
Mechanism of death:
a) Immediate death:
1. Cerebral anoxia: due to pressure on the carotid and vertebral arteries.
2. Asphyxia: due to compression of the trachea and elevation of the root of tongue
against the posterior wall of pharynx and folds the epiglottis over the entrance of
larynx to block the airway.
3. Reflex vagal inhibition: due to compression of vagal sheath.
4. In cases of "judicial hanging”: Fracture dislocation of upper cervical vertebrae
occurs leading to transaction of the spinal cord. This occurs as the victim falls too
far, 5-7 feet. Consciousness is lost immediately, though the heart may continue to
beat for 8-20 minutes with violent respiratory movements.
b) Delayed death:
Death may occur after few hours or days due to:
1. Aspiration pneumonia.
2. Edema of the glottis and lungs.
3. Encephalitis.
4. Hypoxic encephalopathy.
Postmortem picture:
a) External classical signs of asphyxia:
- Most cases show none of the classical signs of asphyxia but the signs are more
marked in cases of incomplete suspension, where veins are more obstructed, there is
engorgement of head and neck. If the pressure constricts the arteries and veins the
face is usually pale.
- Neck may be stretched and elongated.
- Head is bent opposite to the knot.
- Tongue is swollen, coming out and there tip may be black due to drying.
- Excessive salivation comes from a corner of the mouth which is an indicator of antemortem hanging. It is due to pressure on salivary glands by the ligature. It is necessary
to search for any dried saliva on the face, neck and chest.
- Blood tinged fluid or bloody froth is sometimes seen in the nostril due to congestion
in the lungs and pulmonary edema.
- There may be erection of the penis and may show semen drops coming out
- Hypostasis is most marked in the dependent parts (arms, legs) due to
prolonged hanging posture.
b) External evidence of violence on the body:
No other injuries are present over the body, when injuries are present they should be
carefully interpreted whether they are self-induced or produced by a second party in a
homicide.
c) Local Findings (ligature mark):
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- If fixed knot type of noose is used, ligature mark on the neck will be in the form of a
groove or a furrow. This groove does not completely encircle the neck, but slants
upwards, towards the knot, taking an inverted V- shaped with the apex of the "V" at
knot. It fades out at the point of suspension (the knot). Ligature mark may be
interrupted due to beard, long hair, clothes between the ligature material and the neck.
- If a simple slipknot type of noose is used, the ligature groove is completely encircles
the neck.
Position of ligature mark: In 80% of cases, it is present above the thyroid cartilage,
in 15% at the level and in 5% is present below the thyroid cartilage
Appearance of the groove:
- The ligature mark may be pale, yellowish or yellow brown and look like parchment
due to drying of the abraded skin. A thin line of congestion or haemorrhage will be
seen above and below the groove at some areas, usually at the deepest one.
- The width of the groove is about or slightly less than the width of the ligature
material
- A definite pattern of the ligature may be seen but when fresh, the ligature
mark is less clear. After drying it becomes well marked.
d) Internal findings:
- Tissues under the ligature mark are dry, white and glistening.
- Laceration, ecchymosis and rupture of the neck structures may be seen.
- Carotid artery my show transverse tears in the intima.
- Fractures of the hyoid bone and thyroid cartilage are rare (15-20%) below the age of
40 years due to elasticity and the mobility of the joints. If the fracture occurs, it
usually found at the greater horn (outward fracture) due to backward compression of
the bone against the vertebrae.
- Fracture dislocation of upper cervical vertebrae with transaction of the spinal cord in
cases of judicial hanging.
- Abdominal organs are congested and subarachnoid effusion is commonly seen in the
brain.
(2) Strangulation
It is a form of violent asphyxia which is caused by constriction of neck without
suspending the body.
It is mainly of two types:
A- Ligature strangulation.
B- Manual strangulation.
Ligature strangulation
This is the type of strangulation in which a Ligature material is used to compress the
neck and the assailant applies the constricting force without suspending the body.
Manner of Death:
1- Homicidal strangulation:
- It is a common form of murder.
- It is commonly seen in adult women usually combined with sexual assault.
- It is suspected if:
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Limbs are tied, mouth is gagged, presence of signs of struggle, circumstantial evidence
and examination of the scene of the crime.
2- Accidental Strangulation:
- It is rare but has been reported.
- In industry parts of clothing (tie or scarf) may be entangled in a moving
machine.
- Umbilical cord may accidentally strangulate the fetus.
3- Suicidal strangulation:
- It is uncommon but some cases have been recorded.
- A person can have one or two knots before consciousness is lost. Some arrangement
is always made to keep the ligature tight. A cord may be tide around and twisted by
stick working as a lever.
- No signs of struggle are seen.
- Examination of surrounding, and presence of suicidal note are helpful towards the
manner of death.
Mechanism of Death :
1- Asphyxia due to elevation of the larynx against the tongue, which closes the air
way. Trachea or the larynx itself may be block if there is extreme pressure is applied.
2- Cerebral anoxia is caused by compression of the neck blood vessels, (carotid
arteries). Consciousness is lost in 10-15 seconds.
3- Reflex vagal inhibition of the heart and cardiac arrest.
Postmortem Picture:
(A) External Signs:
1- General external classical signs of asphyxia if the death due to asphyxia
&/ or cerebral anoxia.
2- Signs of violence and struggles on the body in case of homicidal
strangulation.
3- Ligature mark on the neck:
- Completely encircle the neck, at the level of thyroid cartilage or below.
- Incomplete if clothing or long thick hair being interposed between the
ligature and neck.
- It is usually horizontal but may be oblique if the victim has been dragged
by the assailant.
- The mark is faint or absent in young children or incapacitated adults,
especially if the ligature is soft (towel) and removed immediately after
death. The mark is very prominent and deep in case of thin tough ligature.
- The mark takes shape of the used rope.
- Ligature material such as cords, ropes and wires causes abrasions of the
surface that becomes hard yellowish brown and parchment like on drying.
- Commonly a narrow zone of reddening and cognition is found
immediately above and below the groove of ligature mark.
- Linear, irregular or crescentic scratch abrasions are usually found near the
ligature mark.
(B) Internal Signs:
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1- Internal classical signs of asphyxia.
2- Internal signs on the neck:
- Haemorrhages are found in the muscles and soft tissues underneath the
ligature mark.
- If severe force is applied tearing of the carotid artery may be present.
- Fracture of hyoid bone and thyroid cartilage may be seen but not common
as hanging. If hyoid fracture occurs it is due to inward compression
(inward fracture), which can be bilateral.
Manual Strangulation (Throttling)
Type of violent asphyxia produced by compression of the neck manually i.e. by
human hands or forearm.
Manner of Death:
Homicidal throttling:
- It is a common mode of homicide.
- The victim is an infant, a child or woman. Healthy adult can be throttled only when
he is under the influence of drugs or other intoxication.
- It is a common method of infanticide.
- A man throttled a woman is usually associated with a sexual attack.
Suicidal throttling:
- It is impossible as when the pressure by the victim's own hands is sustained for a
sufficient time to cause unconsciousness, the hands relax and the victim recovers.
Accidental throttling:
- This may occur just by touching, grasping, or striking the victims neck, without
applying continuous pressure, which can cause sudden death from reflex vagal
inhibition.
Mechanism of Death:
1- Compression of the carotid arteries resulting in cerebral hypoxia or anoxia which
may be fatal.
2- Asphyxia due to occlusion of the airway but it may play a minor role.
3- Reflex vagal inhibition due to stimulation of the carotid sinuses. The compression
or stimulation of the carotid sinuses causes bradycardia, vasodilatation, hypotension
and cardiac arrest.
Postmortem Picture:
A) External signs:1- External classical signs of asphyxia:
-same as in ligature strangulation.
2- Signs of violence and struggles on the body:
-in case of homicidal throttling.
3- Local signs on the neck:
- The site and extent of bruises and finger nail abrasions on the neck will depend on:
1- The Position of the assailant and victim.
2- Manner of grasping the neck and degree of pressure.
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 We can know whether the assailant is left or right-handed or used both hands,
from the distribution of finger nail abrasions and contusions on the sides of the
neck.
 Many scratches are produced by the victim while trying to pull away from the
assailant's hand. Parallel lines in vertical direction are seen in such cases.
B) Internal signs:
1- Internal classical signs of asphyxia.
2- Internal signs on the neck:
a) Hemorrhage in the muscles of the neck.
b) Fracture of hyoid bone is very common especially in the elderly. It is seen as
inward fracture (inward compression), which can be bilateral.
c) Thyroid cartilage may also be fractured in many cases.
d) Bruising at the base of the tongue may sometimes be the only evidence of
throttling.
N.B.: No evidence of trauma either external or internal when the victim is unconscious
at the time of assault or when the death occurs suddenly due to reflex vagal inhibition.
REFERENCES
Knight, B. and Pekka, S. (2004): Suffocation and asphyxia. In: knight's forensic
pathology.
El Gendy & Haggag Handbook of Forensic Medicine (2003): Asphyxia
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