1. The document discusses different types of asphyxia including suffocation, strangulation, and chemical asphyxia. It provides details on six forms of suffocation - entrapment, smothering, choking, mechanical suffocation, mechanical suffocation with smothering, and suffocation gases. 2. Specific causes, mechanisms of death, autopsy findings, and circumstances associated with each type are described. For example, entrapment causes environmental suffocation by oxygen deficiency, while smothering is usually homicidal and involves blocking air flow with objects. 3. The manner of death can be natural, accidental, homicidal or suicidal depending on the circumstance and various factors like physical condition and intoxication level

1. MEDICOLEGALASPECTS OF THEMEDICOLEGALASPECTS OF THE
SPECIAL TYPESSPECIAL TYPES
 Loosely ground in three categoriesLoosely ground in three categories
SuffocationSuffocation
StrangulationStrangulation
Chemical AsphyxiaChemical Asphyxia

2. SUFFOCTIONSUFFOCTION
“Purest form of Asphyxia”“Purest form of Asphyxia”
 Caused by mean other than the constricionCaused by mean other than the constricion
of Neck by hands, ligature or other meansof Neck by hands, ligature or other means
Mechanism / Mode of deathMechanism / Mode of death
is “Anoxic Anoxia” as Ois “Anoxic Anoxia” as O22 fails to reach bloodfails to reach blood

3. Six General FormsSix General Forms
1.1. EntrapmentEntrapment
2.2. Smothering / GaggingSmothering / Gagging
3.3. ChokingChoking
4.4. Mechanical SuffocationMechanical Suffocation
5.5. Mechanical Suffocation withMechanical Suffocation with
SmotheringSmothering
6.6. Suffocation GassesSuffocation Gasses

4. ENTRAPMENTENTRAPMENT
“Environmental Suffocation”
 Individual inadvertently enter an area whereIndividual inadvertently enter an area where
there is gross deficiency of Oxygen.there is gross deficiency of Oxygen.
(Due to depletion of O2 by some(Due to depletion of O2 by some
mechanism e.g. rust formation and notmechanism e.g. rust formation and not
displacement of O2 by toxic or inert gasesdisplacement of O2 by toxic or inert gases
e.g. sewers, mines, deep wells)e.g. sewers, mines, deep wells)

6.  Seen in discarded refrigerator, trunk, ship’sSeen in discarded refrigerator, trunk, ship’s
tank, underground chambers etc.tank, underground chambers etc.
 Manner of deathManner of death is almost alwaysis almost always
Accidental. Suicide / Homicide is rareAccidental. Suicide / Homicide is rare
(mentally sick)(mentally sick)

7.  Cause of deathCause of death cannot be determined bycannot be determined by
autopsy alone, as there are no specificautopsy alone, as there are no specific
autopsy findings. Circumstantial evidence &autopsy findings. Circumstantial evidence &
exclusion of other causes will help toexclusion of other causes will help to
resolve.resolve.

8.  Autopsy FindingsAutopsy Findings non-specificnon-specific
pathological findings are quitepathological findings are quite
marked, as death is usually themarked, as death is usually the
result of slow Asphyxia.result of slow Asphyxia.

9. SMOTHERING / GAGGINGSMOTHERING / GAGGING
 Manner of death is usually Homicidal, rarelyManner of death is usually Homicidal, rarely
Suicidal or AccidentalSuicidal or Accidental
 Homicidal SmotheringHomicidal Smothering is practicable only whereis practicable only where
there is gross physical disparity betweenthere is gross physical disparity between
assailant and victim by virtue of age, ill health,assailant and victim by virtue of age, ill health,
debility or incapacity due to disease, drink ordebility or incapacity due to disease, drink or
drug.drug.

11. It is extremely difficult to smother aIt is extremely difficult to smother a
healthy, robust, adult who is in full controlhealthy, robust, adult who is in full control
of his mental faculties, unless he is notof his mental faculties, unless he is not
stunned with a blowstunned with a blow
Commonest examples are of infant andCommonest examples are of infant and
child killing with implements like hands,child killing with implements like hands,
pillows, beddingpillows, bedding

12. SUICIDAL SMOTHERINGSUICIDAL SMOTHERING
 Suicidal SmotheringSuicidal Smothering is seen inis seen in
prisoners, mental patients by buryingprisoners, mental patients by burying
face in “Flock Mattress” or by lyingface in “Flock Mattress” or by lying
against “Bed Clothing” especially whenagainst “Bed Clothing” especially when
drunk or by placing a ”Plastic Bag” overdrunk or by placing a ”Plastic Bag” over
face / headface / head

13. ACCIDENTAL SMOTHERINGACCIDENTAL SMOTHERING
Accidental Smothering is rare varietyAccidental Smothering is rare variety
where circumstances changes with age ofwhere circumstances changes with age of
the victimthe victim
InfantInfant weight of bedding, pillow, mattressweight of bedding, pillow, mattress
ChildrenChildren polythene helmetpolythene helmet
AdultsAdults when drunk intoxicated or duringwhen drunk intoxicated or during
epileptic fit, fall face down into mud, snowepileptic fit, fall face down into mud, snow
or think grassor think grass

14. GAGSGAGS
 GagsGags can cause death, thoughcan cause death, though
unintentional yet homicidal, in femalesunintentional yet homicidal, in females
during rape and in elderly duringduring rape and in elderly during
commission of crime. The presence ofcommission of crime. The presence of
gag over face and other findings willgag over face and other findings will
confirm the diagnosis at autopsyconfirm the diagnosis at autopsy

16. PLASTIC BAGPLASTIC BAG
SMOTHERING/SUFFOCATIONSMOTHERING/SUFFOCATION
Plastic / polythene bag has revolutionized thePlastic / polythene bag has revolutionized the
packing industry but has brought a specificpacking industry but has brought a specific
hazard. Children are at special riskhazard. Children are at special risk (Polythene(Polythene
helmet / spaceman game)helmet / spaceman game)
Potential agents for suicide, homicide andPotential agents for suicide, homicide and
accident (Infanticide, child killing, autoeroticaccident (Infanticide, child killing, autoerotic
practices and narcotic misadventure duringpractices and narcotic misadventure during
inhaling anesthetic agents).inhaling anesthetic agents).

18. CHOKINGCHOKING
 Manner of death can be Natural, Homicidal,Manner of death can be Natural, Homicidal,
Accidental or rarely SuicidalAccidental or rarely Suicidal
 Mechanism of asphyxia in choking is simpleMechanism of asphyxia in choking is simple
mechanical obstruction leading tomechanical obstruction leading to anoxicanoxic
anoxiaanoxia but entry of foreign material may causebut entry of foreign material may cause
sudden death fromsudden death from vagal inhibitionvagal inhibition (café(café
coronary) or larvngeal spasmcoronary) or larvngeal spasm

20. NATURAL DEATHSNATURAL DEATHS
1.1. InternallyInternally include acute fulminatinginclude acute fulminating
epiglottis, laryngitis, edema / tumors ofepiglottis, laryngitis, edema / tumors of
larynx, pharyngeal abscesslarynx, pharyngeal abscess
2.2. ExternallyExternally impaction of large FB, bolusimpaction of large FB, bolus
of food or denture in esophagus causingof food or denture in esophagus causing
compression of trachea.compression of trachea.

21. HOMICIDAL DEATHSHOMICIDAL DEATHS
 Homicidal DeathsHomicidal Deaths are uncommon, as theirare uncommon, as their
accomplishment requires gross physicalaccomplishment requires gross physical
disparity or diseased, drunk or intoxicateddisparity or diseased, drunk or intoxicated
victim. Death due to regurgitation of food mayvictim. Death due to regurgitation of food may
occur during rape / sexual intercourseoccur during rape / sexual intercourse

22. ACCIDENTAL DEATHACCIDENTAL DEATH
 Accidental DeathsAccidental Deaths are common in childrenare common in children
due to aspiration of small rubber balls coins,due to aspiration of small rubber balls coins,
and buttons. In adults it virtually alwaysand buttons. In adults it virtually always
involve food (Café coronary) that is commonlyinvolve food (Café coronary) that is commonly
associated with alcohol, loose denture, senility,associated with alcohol, loose denture, senility,
neurological injuryneurological injury
 Suicidal DeathSuicidal Death is practicable only inis practicable only in
mentally sick individualsmentally sick individuals

23.  Choking may lead to vagal inhibitionChoking may lead to vagal inhibition andand
death in infants inhaling tiny feather of a petdeath in infants inhaling tiny feather of a pet
i.e. cat, dogi.e. cat, dog
 Choking may cause laryngeal spasmChoking may cause laryngeal spasm andand
death due to entry of a foreign material not ofdeath due to entry of a foreign material not of
large size but of irritant nature like acid gastriclarge size but of irritant nature like acid gastric
juice entering the air passagesjuice entering the air passages

24.  Autopsy FindingsAutopsy Findings are non-specific as thereare non-specific as there
are no specific findings indicative of chocking.are no specific findings indicative of chocking.
Airway when full from larynx to the mainAirway when full from larynx to the main
bronchi is only suggestive, as 20- 25 %bronchi is only suggestive, as 20- 25 %
individuals normally aspirate food agonally,individuals normally aspirate food agonally,
independent of the cause of deathindependent of the cause of death

25. MECHANICAL SUFFOCATIONMECHANICAL SUFFOCATION
 Manner of death is always AccidentalManner of death is always Accidental
Traumatic AsphyxiaTraumatic Asphyxia
Positional AsphyxiaPositional Asphyxia
Riot crush or human pile deathRiot crush or human pile death
 Traumatic AsphyxiaTraumatic Asphyxia
Direct compressionDirect compression of chest by a heavy weightof chest by a heavy weight
against resisting surfaceagainst resisting surface
 Indirect CompressionIndirect Compression i.e. Jack Knife Positioni.e. Jack Knife Position

27. AUTOPSY EXAMINATIONAUTOPSY EXAMINATION
 Autopsy ExaminationAutopsy Examination reveals signs ofreveals signs of
slow asphyxia i.e. deep congestion of faceslow asphyxia i.e. deep congestion of face
& head with numerous petechae, blood shot& head with numerous petechae, blood shot
eyes, proptosis, retinal haemorrhages, welleyes, proptosis, retinal haemorrhages, well
– marked demarcating line on chest,– marked demarcating line on chest,
multiple bilateral (indirect) rib fractures.multiple bilateral (indirect) rib fractures.

28.  Positional AsphyxiaPositional Asphyxia is associated withis associated with
alcohol or drug intoxicationalcohol or drug intoxication
 Riot crush or human pile deathRiot crush or human pile death is seen inis seen in
stamped during riots and Hajj.stamped during riots and Hajj.

29. MECHANICAL SUFFOCATIONMECHANICAL SUFFOCATION
COMBINED WITH SMOTHERINGCOMBINED WITH SMOTHERING
 OverlayingOverlaying is seen in infants (2-16 week)is seen in infants (2-16 week)
sharing bed with adults. Poverty andsharing bed with adults. Poverty and
overcrowding play a potential role. D/D fromovercrowding play a potential role. D/D from
SIDSSIDS
 Death is Classified asDeath is Classified as UNDETERMINEDUNDETERMINED ifif
two possibilities cannot be differentiated.two possibilities cannot be differentiated.
 BurkingBurking death is always homicidaldeath is always homicidal

30. SUFFOCATION GASESSUFFOCATION GASES
“Environmental Asphyxia” “Vitiated Atmosphere”“Environmental Asphyxia” “Vitiated Atmosphere”
 Deficiency of ODeficiency of O22 is due to displacement of O2 byis due to displacement of O2 by
toxic / inert gases like COtoxic / inert gases like CO22, CO, SO, CO, SO22, H2S & CH, H2S & CH44
 Manner of deathManner of death is almost always accidentalis almost always accidental
 History, Circumstantial Evidence, ToxicologicalHistory, Circumstantial Evidence, Toxicological
Profile like Knuckle & Hop sellers test for CO,Profile like Knuckle & Hop sellers test for CO,
sulphmet Hb in Hsulphmet Hb in H22S and acid hematin in SOS and acid hematin in SO22 andand
Exclusion of other causes will help to establishExclusion of other causes will help to establish
diagnosisdiagnosis

31. SEXUAL ASPHYXIASEXUAL ASPHYXIA
““Autoerotic asphyxia” “Autoerotic Death”Autoerotic asphyxia” “Autoerotic Death”
““Sex Hanging”Sex Hanging”
 Little understood, unusual type, having anLittle understood, unusual type, having an
extremely bizarre picture showing bothextremely bizarre picture showing both
EROTIC and ASPHYXIAL findings alongEROTIC and ASPHYXIAL findings along
with traits of MASOCHISM andwith traits of MASOCHISM and
TRANSSEXUALSTRANSSEXUALS

32.  Death occurs in the course of sexual fantasiesDeath occurs in the course of sexual fantasies
during the course of solitary erotic behavior,during the course of solitary erotic behavior,
principally due to hanging in which theprincipally due to hanging in which the
asphyxia in induced to accentuate sexualasphyxia in induced to accentuate sexual
gratification produced by masturbationgratification produced by masturbation
 OriginOrigin
 AgeAge
 SexSex

33.  Social ClassSocial Class
 ClothesClothes
 SceneScene
 Condition of bodyCondition of body
 Mode / Manner of deathMode / Manner of death
 Objective / BehaviorObjective / Behavior

34.  Limitations for investigationLimitations for investigation
 Conclusion Combination of PerversionsConclusion Combination of Perversions
““Masochism” “Transvestism” andMasochism” “Transvestism” and
“Narcissism”“Narcissism”