Violent Asphyxial Death PDF

Part III: Forensic Pathology Violent Asphyxial Death 15 LEARNING OBJECTIVES PA...

Part III: Forensic Pathology Violent Asphyxial Death 15 LEARNING OBJECTIVES PATHOPHYSIOLOGY OF ASPHYXIA Definition of Asphyxia Conventionally, the term asphyxia has been applied to all Etiology of Asphyxia conditions in which oxygen supply to blood and tissue has been Signs and Symptoms of Asphyxia reduced appreciably below the normal working level by any Pathophysiology of Asphyxia interference with respiration. In death from asphyxia, usually Mechanical/Violent Asphyxial Death it falls below the minimum necessary for continuance of life. Define and describe the postmortem findings and the Serious deprivation of oxygen for 5 to 10 minutes can result medicolegal aspects of: in permanent damage to central nervous system and cardio- – Hanging vascular system resulting in death. It is interesting to note that – Strangulation in a healthy adult body, normally blood that is circulating has – Suffocation about 1 litre of oxygen held in combination. Any interference – Drowning. with this results in asphyxia, which in turn triggers the INTRODUCTION consequences. This renders the pathophysiology of asphyxia, Deaths due to asphyxia are caused by failure of cells to receive depicted in Figure 15.1B in a cyclical form and is nonstopping or utilize oxygen. The deprivation of oxygen may be partial and continuous event till death of the person; hence it is a vicious (hypoxia/ suboxia) or total (anoxia/anoxemia).1 Literal meaning cycle.3-6 of word ‘asphyxia’ is ‘no pulse’ (pulse less). It is also understood ANOXIA as a ‘state of low oxygen’ (hypoxia/suboxia, anoxia, etc). Thus According to physiological concepts, asphyxia can lead to lack the terminologies anoxia, anoxemia, suboxia, hypoxia, etc. are of oxygen supply to cells and tissues. Among all, nervous tissues though considered as better ones, the terminology “asphyxia” are affected first by oxygen deficiency. This lack of oxygen supply remains accepted in true medicolegal sense globally. However, is known as anoxia. the pathophysiology would include biochemical and neurological mechanisms. DEFINITION OF ASPHYXIA Asphyxia is defined as lack of oxygen in blood and tissues due to impaired or absence of exchange of oxygen and carbon dioxide on a ventilatory basis, leading to death.2 ETIOLOGY OF ASPHYXIA Asphyxia can develop because of several causes such as: Physical causes—breathing in high altitudes with rarefied/ vitiated medium, deficient of O2, e.g. mountaineering. Inhaling irrespirable gases, such as gases interfering with normal O2 carrying capacity of blood haemoglobin, e.g. CO, CO2, H2S, etc. or gases which prevent cellular oxidation enzymes, e.g. HCN. Drugs/poisons—directly depressing the respiratory centres, e.g. narcotics (morphine), anaesthetics, etc. Mechanical asphyxia—this is due to mechanical interference to respiration, e.g. hanging, strangulation, throttling, smothering, choking, drowning, etc (Fig. 15.1A). Pathological asphyxia—this is due to diseases, e.g. lung pathology. Allergic reactions causing laryngeal oedema. Fig. 15.1A: Causes of mechanical asphyxia 194  Chapter 15: Violent Asphyxial Death Fig. 15.1B: Pathophysiology of asphyxia Gordon’s Classification of Anoxia of following types depending upon the respiratory block (Fig. 3-5 According to Gordon, anoxia is classified as follows: 15.2B). Anoxic Anoxia: Here oxygen cannot gain entry into the 1. Compression/ constriction of the neck, e.g. hanging, blood, e.g. hanging with obstruction of trachea—here no strangulation, throttling, etc. oxygen enters the pulmonary circulation, hence, there is no 2. Blocking external orifices of respiration, i.e. mouth and/or oxygen in the blood. nostrils, e.g. smothering, overlying, suffocation, gagging, etc. Anemic Anoxia: Here oxygen can get into blood, but the 3. Impaction of foreign bodies in respiratory tract, e.g. choking blood is incapable of carrying it, e.g. carbon monoxide 4. Compression and mechanical fixation of the chest and poisoning, wherein the carboxyhemoglobin formed prevents abdomen preventing the respiratory movements, e.g. blood oxygenation. traumatic asphyxia/crush asphyxia. Stagnant Anoxia: Here oxygen can get into the blood, blood 5. Inhalation of fluid into the respiratory tract, e.g. drowning. is capable of carrying it, but circulation is at failure, e.g. HANGING congestive cardiac failure. Histotoxic Anoxia: Here oxygen can get into the blood, blood Definition is capable of carrying it, and the blood circulation is perfectly Hanging is defined as complete or partial suspension of the normal, but the cell cannot utilize the oxygen available in body by a ligature tied around the neck and force of blood, e.g. cyanide poisoning, here the cyanides destroy the constriction on the neck being applied by the weight of the body cellular oxygen enzyme system cytochrome oxidases. hanged.3-6 Histotoxic anoxia can be further classified as follows: Causes of Death Extracellular histotoxic anoxia – Here oxygen cannot be taken In hanging, death is usually due to asphyxia or cerebral anoxia up due to the failure of tissue enzyme system by poisoning, or vagal inhibition leading to cardiac arrest or injury to the spinal e.g. cyanide, overdose of hypnotics or anaesthetics. cord as observed in judicial hanging wherein death is due to Pericellular histotoxic anoxia – Here oxygen cannot be taken fracture-dislocation of the C2C3C4 vertebrae.1,4,6 up due to reduced permeability of cell membrane, e.g. lipoid Classification of Hanging1-6 soluble anaethestic agents such as chloroform, halothane, Complete hanging—both feet are not touching the ground etc. (Fig. 15.3A and C). Substrate histotoxic anoxia – Here oxygen cannot be taken Partial hanging—both feet or any other parts of the body up due to failure of efficient cell metabolism, e.g. hypo- are touching the ground. Thus, it may be also induced in gylcaemia, etc. sitting, stooping, kneeling, lying prone or supine positions Metabolite histotoxic anoxia – Here oxygen cannot be taken (Figs 15.3B and D to F). up due to the accumulation of end products of cell respi- Typical hanging—knot of ligature is on the backside of the ration, e.g. carbon dioxide poisoning, uremia, etc. neck (Figs 15.4A and C). Atypical hanging—knot of the ligature is anywhere other than CLINICAL EFFECTS OF ASPHYXIA on the backside of the neck (Figs 15.4B and D to F). Usually A schematic representation of clinical effects of asphyxia may location for the knot is near the mastoid process or angle be presented as in Figure 15.2A. of mandible. Occasionally, it may be under the chin (Fig. 15.4G). CLASSIFICATION OF MECHANICAL/ VIOLENT ASPHYXIA Mechanism of Hanging Interference of respiration by mechanical means constitutes It has been scientifically accepted that pressure on the neck can mechanical or violent asphyxia. Mechanical asphyxia could be result in occlusion of neck structures for respiratory functioning, 195 Part III: Forensic Pathology Fig. 15.2A: Clinical effects of asphyxia Fig. 15.2B: Types of mechanical asphyxial deaths developing asphyxia. Experimentally, it has been proven that AUTOPSY FINDINGS pressure/force of 2 kg (4.4 lbs) and 4-5 kg (8.8-11 lbs) on the Autopsy findings are discussed under two heads; external and neck can occlude jugular vein and carotid arteries respectively, internal findings. 15 kg (33 lbs) can occlude trachea and 30 kg (66 lbs) can occlude vertebral arteries.4,8 All these can bring about gross decrease EXTERNAL in cerebral blood flow leading to cerebral anoxia, asphyxia and All external findings are better sedlt under three heads, namely: death. I. Findings in the face 196 II. Findings in the neck Pallor/congestion – Usually in most hangings, the face is Chapter 15: Violent Asphyxial Death III. Findings in other parts. pale.1 However it may be swollen and congested (Fig. 15.5B), Each one of these is discussed separately with suitable with petechiae in partially suspended individuals, where the illustrations. noose is tightened only by the weight of the head or the torso. In these instances while the carotid arteries and venous I. Findings in the Face drainage are completely occluded, vertebral arteries still Findings suggestive of antemortem hanging are illustrated in continue to supply blood to the head, producing accumu- Figures 15.5A to E and discussed below: lation of blood.1,4,6 With time dependent accumulation of blood, punctuate hemorrhages and Tarideu spots, caused by hydrostatic rupture of vessels, will be seen on the forehead, over the eyelids, under the conjunctiva and sometimes near the temple (Fig. 15.5A).1,9 Lips – may show cyanotic tinge (Fig. 15.5C). Changes in the eyes – Eyes may show following findings: – Prominent eyeballs – Eyeballs may look prominent due to increased pressure as a consequence of impaired circulation and venous return resulting in passive accumulation of blood (Fig. 15.5D). – La-facie sympathique – Etienne Martin (1950) described Figs 15.3A and B: Types of hanging: (A) Complete hanging; this peculiar change wherein right eye remaining open (B) Partial hanging with dilated pupil and the left eye closed with small pupil.8 Figs 15.3C to E: Types of hanging: (C) Complete hanging: (Atypical) (Courtesy: Dr NG Revi, Professor & HOD, Police Surgeon, Dept of Forensic Medicine, Medical College, Trichur, Kerala; (D) Partial hanging in sitting position (Courtesy: Dr. SC Mestri, Professor and HOD, Dept of Forensic Medicine, JSS Medical College, Mysore, Karnataka); (E) Double suicidal hanging (mother and daughter): Partial hanging (Courtesy: Dr B Chandre Gowda, Formerly Professor Figs 15.3F and G: Types of hanging: Suicidal hanging and partial and HOD, with permission of Dr Kiran J Head, Dept of Forensic hanging with feet on the ground (Courtesy: Manipal Police Station, Medicine, SDU Medical College, Kolara, Tamaka, Karnataka) Manipal) Figs 15.4A and B: Types of hanging: (A) Typical and atypical hanging. (B) Possible ligature mark positions in the neck in hanging: (i) More common/usual position with fixed noose and high suspension. Mark rises high and may show a gap; (ii) When a slip knot is used it results into a smallest loop, that tightens maximum resulting into a deep ligature mark in the neck, could be low and horizontal; (iii). When the suspension point is low and victim leans away and mark will be horizontal, misleading for strangulation 197 Part III: Forensic Pathology Figs 15.4C to F: Suicidal hangings: (C) Typical hanging – Knot on the back side but high above; (D) Atypical hanging with suicidal note affixed on front of the shirt (Courtesy: Dr. Sreemathi Rajagopalan, St. John’s Medical College, Bengaluru, Karnataka); (E) Atypical hanging (Courtesy: Dr Ritesh G Menezes, Assoc. Prof. KMC, Mangalore, Karnataka); (F) Atypical hanging – knot in the front (Dr B Chandre Gowda Formerly HOD, with permission of Dr Kiran J Head, Dept of Forensic Medicine, SDU Medical College, Kolara, Tamaka, Karnataka) Figs 15.5B and C: External autopsy findings in hanging: (B) Swollen, cyanosed, face; (C) Protrusion of tongue (Courtesy: Capt. Dr. Santha Kumar, Professor & HOD, Forensic Medicine, Govt. Kilpauk Medical College, Chennai, Tamil Nadu) Fig. 15.5A: External autopsy findings in hanging Thus, in the eyes of victim of hanging, wherein one of Figs 15.5D and E: Hanging – Eye findings: Prominent eyes with subconjunctival haemorrhages. (Courtesy: Dr. B. Suresh Kumar the eyes may be opened with dilated pupil, while the Shetty, Asst. Professor, Dept of Forensic Medicine, KMC, other eye may be closed. This occurs due to the pressure Mangalore, Karnataka) of the ligature/knot on the cervical sympathetic ganglia in the neck. Thus, the side on which the ligature/knot presses the cervical sympathetic ganglia, the eye remains Changes in the tongue – Tongue may be protruded out open with dilatation of its pupil.8 (Fig. 15.5C) due to pressure on the floor of the mouth by – Subconjunctival hemorrhages (Figs 15.5D and E). the ligature material from below pushing the tongue out of Petechial haemorrhagic spots may be noticed with the oral cavity. Protruded portion of tongue often turns black subconjunctival tissues and inner aspect of the eyelids.7 due to drying.1 198  Bleeding from nose/ears – Due to the impaired venous II. Findings in the Neck Chapter 15: Violent Asphyxial Death return and increase in pressure within, resulting in rupture Findings in the neck are basically two only and they are: of vessels and passive flow of the blood from nostrils and 1. Distended neck veins – Prominently distended neck veins, ears. above the ligature. Salivary dribbling marks – It is a constant and important 2. Ligature mark of hanging – A detailed knowledge about finding in case of death due to hanging. Normally salivary the ligature mark of hanging essential for an autopsy surgeon, secretion is a constant phenomenon in life, however, it is is highlighted precisely in Figures 15.5G to K, and described being swallowed continuously. When death takes place the below: deglutition also stops, while the local pressure and irritation exerted by the ligature on submandibular salivary glands continues and this results in secretion of saliva. This can flow passively through the lower angle or dependent parts of the mouth, and is suggestive of antemortem hanging3-6,9 (Fig. 15.5F). Dribbling occurs from the angle of mouth whichever is at lower level, i.e. from the angle opposite to the side of knot. When the knot is on the nape of neck it occurs from middle of the lower lip. When the knot is under the chin, then it occurs through either or both of the angles of the mouth.9 The saliva that dribbled out drops down in front of the chest when body is bare or it stains the clothes in front, when the victim is dressed. When dried or partly dried, it becomes quite fixed and cannot be easily removed or rubbed off. However, salivation can be also due to asphyxia and congestive hypoxia. Salivation may not occur, when death is due to vagal inhibition. Evidance of salivation should always be looked for testing the presence of mucin in it by turning blue if treated with iodine, during autopsy.3 However, Fig. 15.5F: Hanging case with salivary dribbling marks on front of rough handling of the dead body kept in the cold chamber the face at and below the left side angle of the mouth and front and might remove these stains.4-6 left side of the chest and abdomen Figs 15.5G to K: Ligature mark of antemortem hanging: (G) Hanging in situ; (H) front view – mark running horizontally upwards towards point of suspension; (I) Left lateral view-running behind left ear over mastoid process; (J) Right lateral view – mark is at lower level than on left side, but oblique and moves upwards towards point of suspension; (K) Back view—noncontinuous due to the hairs intervene. Note: Inverted ‘V’ shape 199  Site – seen round the neck; usually situated above the producing two ligature marks. In such cases a wider Part III: Forensic Pathology thyroid cartilage (Adam’s apple) in about 75 per cent abraded area may be noticed due to frictional of cases of hanging, at the level of thyroid cartilage in displacement of the ligature material. When ligature is another 15 per cent and below the thyroid cartilage in applied in multiple turns, multiple, parallel, grooved remaining 10 per cent cases.4,7,8 ligature marks may be seen. Size/shape – depends on the type of material used. 6. Microscopy of ligature mark: it shows usual characteristics Cause – weight of the body tightening the ligature of an abrasion, with desquamation and flattening of cells material around the neck. of the epidermis. There may not be findings of any vital Appearance – A typical ligature mark is usually seen reaction if the death occurred immediately after asphyxiation. in antemortem hanging. It is also reported to appear if 7. Other factors influencing appearance of ligature mark: hanged immediately after death or within a period of Other factors which influence the appearance of ligature mark 2 hours of death (vide infra).11 However, ligature mark are several as noticed and enumerated below: produced so will not be as prominent as in antemortem Period of suspension – more the period of suspension, hanging. more prominent will be the ligature mark. Degree of suspension – total suspension routinely presents Typical Ligature Mark of Antemortem Hanging with a prominent ligature mark compared to partial It has following characteristics: suspension. 1. Distribution of the mark: It is non-continuous, placed Weight of the body hanged – heavier is the person high up in the neck, above the level of thyroid cartilage (as hanged, deeper and prominent will be the ligature mark. stated above) and runs obliquely, backwards and upwards Tightness of the ligature – more is the tightness of the towards the point of suspension (Figs 15.5G to K). The ligature, deeper will be the ligature mark. ligature mark is non-continuous in the nape of the neck where Any intervening material – Any intervening material such the hairs intervene between the ligature material and skin as shirt collar, cushioning by a soft cloth pad/ underneath (Fig. 15.5K). Ligature mark may also be non- handkerchief, etc. (as seen with auto-erotic, masochistic continuous at the site of knot due to some gap, produced type of sexual asphyxia cases) between the ligature by the pull on the knot from the point of suspension above. material and skin, can make the ligature marks less When the knot is in contact with the skin it is usually inverted prominent. “V” shaped (Fig. 15.5K), due to extension of ligature material Lengthening and bending of neck – Upon prolonged downward on either sides from the knot above.9 Ligature suspension, neck can become slender and increase in may be continuous in partial hanging. length. However, this is not observed in hanging for short 2. Skin at the site: It is usually depressed, pale, dry, and hard time. The neck may be tilted to opposite side of the knot. and may be with small abrasions at its edges, corresponding This may continue until onset of rigor mortis. to the thickness and edges of the rope used to hang. These 8. The knot – Among most of the right handed suicide victims, abrasions are also known as rope burns and they are due knot is usually seen on the right side of the neck as it is to frictional force.18 easier for the victim to tie himself/herself. Knot may be a 3. The pattern of the ligature: Often the pattern of ligature slip knot or granny knot (Fig. 15.5L). Common site for the used for hanging gets imprinted on the skin as a pressure knot is either right side or left side of the neck. It could be abrasion. If the ligature material used is tough and narrow also on the occiput. Occasionally it is seen below chin also. like a plastic wire or electrical cord, then the ligature mark Ligature marks tend to be deeper opposite to the position is deep and prominent. However, if the ligature material is of knot. When hanging is from a low point of suspension soft and broad, the ligature mark is less prominent and less or partial hanging, the mark may be horizontal and could resemble strangulation. However in most cases of hanging deep. It may not be visible, if a light and thin cloth material it is above the level of thyroid cartilage. like nylon sari is used as ligature material. There may not 9. Availability of ligature material used for hanging with be any ligature mark if the body has been released from cadaver – This may be supplied by the police intact in-situ hanging swiftly after suspension. It may not be seen if around the neck or may/may not be sent separately with anything intervenes between the skin and ligature material the dead body. such as long beard or clothing, etc. Very low point of suspension, old and cachectic body, partial hanging could be the other causes of not vissible ligature mark. 4. Postmortem staining: The upper margin of the ligature mark has a line of postmortem staining, all around above the ligature mark, due to pooling and settling of blood from head and neck above the level of constriction, which becomes the most dependent part vertically.1 5. Double ligature mark: At times there could be a double ligature mark observed. This may occur under following circumstances: A cloth material like a sari or dhoti (Lungi) is used as ligature material, which might have 2 folds (thin) one above the other with thick bands in between the cloth. A ligature which is fastened at times at a lower level on Fig. 15.5L: Slip knot/granny knot (left) and Hangman’s noose the neck may move upwards due to slipping of the body used in judicial hanging (right) 200 10. Removal and preserving of the ligature and noose also show bluish discolouration of fingertips and nail beds Chapter 15: Violent Asphyxial Death – Certain types of knots and nooses may suggest involvement due to cyanosis. of another party in cases which initially appear to be a suicide. Postmortem hypostasis – Purple coloured postmortem In order to enable subsequent examination of a given noose, hypostasis is usually in a peculiar distribution in the lower the knot should not be undone.10,18 Also prior to removal limbs and lower regions of upper limbs (hands/forearm) (Fig. of the noose from the neck, its nature and composition, width, 15.5N) and at the upper margin of the ligature mark, which mode of application, location and type of knot should be are actually lower parts of different body segments in this described in detail. After noting these observations, removal posture. This peculiar distribution of the postmortem staining of the noose is done by cutting it away from the knot and is however, though not suggestive of antemortem hanging, tying the cut ends with a string or a wire.10,18 This will enable speaks of the fact that body was in a state of suspension adequate preservation (Fig. 15.5M). in an upright position for a considerable period after death. 11. Scratch marks on the neck – Rarely, scratch marks may It may also be noticed here that such hypostasis could be be seen on the neck above or below the ligature mark of developed even if a dead body is hanged immediately after hanging, where the victim tried to undo the noose.1 These death (perimortem hanging). are often refered to as ‘periligature marks/injuries’ and are Involuntary voiding of urine and /fecal matter– stains always antemortem in nature.6,7 of which may be seen on the under garments/on the floor 12. Ligature mark and putrefaction – Ligature marks being below. avascular and dry are found to resists putrefaction.18 Hence, Abrasions or contusions on lateral aspect of shoulder, it can be easily noticed in decomposed body even up to feet, toes – Abrasions or contusions on lateral aspect of the 5th day after death (Fig. 15.5M1 to M3). shoulder, feet, toes, etc due to friction with a wall or a pillar during suspension, in the last phase of life when there are III. Findings in Other Parts of the Body convulsions. Injuring parts of the feet or toes may also be Hands – Hands are usually clenched. May be at times the noticed, is again common while making an attempt to jump hands may show the jute fibres, such as that of jute fibre from a support such as a wooden stool or a steel chair or when jute rope is used as the ligature material. Hands may a tree branch at a height, or such other things in the process of inducing suicidal hanging. Otherwise there shall be no other injuries seen. In male victims: – Penile turgidity—penis may be found turgid and erect— no definite causes are described up to date. However this is usually not seen. Several possibilities are presented. Accordingly one of the explanations is that, it could be due to pooling of blood after death into the vascular spaces within the penile musculature due to gravity shifting. – Seminal voiding—seminal emission may be noticed at the tip of the glans penis over the thighs (Fig. 15.5O) or seminal stains may be seen on inner garments, etc. It may also be seen on the floor immediately below the site of hanging. This is explained to be due to sphincter relaxation due to asphyxia of higher centres of the brain controlling these muscles. However, this may also be seen in death due to natural causes. – Voiding of urine and stools – may also be seen due to relaxation of the sphincters. In female victims: Apart from the voiding of urine and Fig. 15.5M: The method of removing the noose stools, turgescence of vagina with blood-stained discharge with intact knot for preserving may also be noticed.4 Figs 15.5M1 to M3: (M1) Both the cadavers M1 and M3 were recovered in hanging position with decomposition changes. (M2 and M3) Ligature marks noticed on the neck 201 Part III: Forensic Pathology Fig. 15.5N: Purplish postmortem lividity over the lower extremities Fig. 15.5P: Heart in a case of hanging. Note: Tardieu’s and forearms. Note: Distribution of lividity is corresponding to haemorrhagic spots on the pericardium dependent parts of the body position which is invariably vertical in hanging Findings in abdominal viscera – All the abdominal viscera are congested. Blood changes – Blood will be fluid and purplish in colour. Neck findings – In every case of death by hanging, a careful dissection of the neck is done, layer by layer, so as to not to miss any of the internal findings, confirming hanging as the cause of death. This is possible only if the dissection area is maintained clean free from bleeding, which can be only achieved by a special technique called bloodless dissec- tion of neck. Bloodless Dissection of Neck This simply means conducting the neck dissection at the end of autopsy examination, after performing dissection of cranium above and thorax and abdomen below, with removal of every other viscera except in the neck. Majority of cases according Fig. 15.5O: Voiding of semen (Arrow)—Seminal stain on inner to the author’s experience, show no internal injuries in the neck. thighs in a victim of antemortem hanging DiMaio reports of only 50 per cent of cases presenting with internal neck injuries in hanging victims.1 Probable neck findings suggestive of antemortem hanging are: External Autopsy Findings in Subcutaneous tissue underneath the ligature mark is dry, Cases of Vagal Inhibition Death whitish, firm and glistening. Here death is instantaneous and hence none of the usual The platysma and the sternomastoid muscles may show asphyxial findings are seen. petechial haemorrhages and may be ruptured occasionally. There may be bruising in the subcutaneous tissue and the INTERNAL muscles, deeper to the mark. Internal autopsy findings include findings in the neck, lungs, Rupture or tears of intima of carotid arteries above its point heart, brain, other abdominal viscera and blood. Of all these, of bifurcation, around the sinuses with extravasation of blood neck findings are more important and will be discussed later. in their walls, especially in cases of a long drop, may be Findings in the lungs – Lungs will be congested, distended observed (Fig. 15.5Q). and emphysematous with plenty of hemorrhagic spots Trauma to hyoid bone and larynx—a brief discussion on (Tardieu’s spots) subpleurally. Cut section usually exudes forensic anatomy of hyoid bone and larynx is appropriate frothy fluid blood, if constriction occurs at the end of at this juncture (Fig. 15.5R). exspiration. It would be pale with little or no congetion, if constriction occurs at the end of inspiration. Forensic Anatomy of Hyoid Bone and Larynx Findings in the heart – Heart is congested and shows Hyoid Bone Tardieu’s haemorrhagic spots over the pericardium (Fig. This is a bone described is have a ‘U’ shape, with a central 15.5P). Right side of the heart, pulmonary artery and vena horizontal body; to which ‘greater horns’ are attached on either cava are usually found full with dark fluid blood, while left side by a natural joint (Figs 15.6A and B). The greater horns side empty.7 lie behind the sternomastoid muscle at its front part, 3 cm below Findings in the brain – Brain and its membrane will be angle of mandible and 1.5 cm away from the midline. Usually, congested and with or without scattered petechiae on its the connection between greater horn and hyoid bone body is surface and substance. cartilaginous in early life, while after middle age it turns bony. 202  Chapter 15: Violent Asphyxial Death Fig. 15.5Q: Demonstrating bloodless dissection of neck in a case of hanging. Note: Dissection of the carotid artery with revealing multiple intimal tears (Arrows) suggestive of antemortem hanging Fig. 15.5R: Rope burns: A pressure abrasion due to frictional irritation (Antemortem sign) (Courtesy: Dr SC Mestri, Professor and HOD, Dept of Forensic Medicine, JSS Medical College, Mysore, Karnataka) However, there are lot of controversies regarding this.7 Hyoid bone has two ‘lessor horns’ located close to the greater horns, but has no medicolegal significances. Figs 15.6A to C: (A) Anatomy of the larynx, (B) Hyoid bone (Normal Larynx morphology), (C) Fracture of hyoid bone in hanging and throttling Larynx is a neck structure in the mid-line anteriorly. However, (probable mechanisms) its exact location varies with sex and age. In an adult male, it lies opposite 3rd-6th cervical vertebrae, while in a female, it is at a higher position slightly. It comprised of nine cartilages; cartilage and gets ossified earlier in men than women; as the namely, thyroid, cricoid, epiglottis and smaller pairs of cuneiform, age advances, begining at about 25 years. However, it may not corniculate and arytenoids. Thyroid and cricoid cartilages are ossify even at advanced old age. more important. Mechanism of Fracture and Fracture Cricoid Cartilage Dislocation of Hyoid Bone Cricoid is of signet ring shape with signet part situated posteriorly. Hyoid bone—usually reported to remain intact (90-95%). It is rarely injured in hanging deaths because of its position and However, if fractured it is usually seen in age group of 40 cartilaginous structure. years and above, at the greater cornu at the junction of inner two-thirds with outer one-third (Figs 15.6C and D). Thyroid Cartilage These fractures usually fall under any one of the following Thyroid cartilage is made up of a shield shaped body in the three types: middle. It is angled at about 90o in a male and 120o in a female. – Antero-posterior compression fracture – Here the distal Its location is being covered merely by fascia and skin, it is highly fragment gets desplaced outwards and periosteum may vulnerable to injury. At its backside, superior and inferior horns be torn on the inner aspect. are attached to the body. The superior horns are firmly attached – Side-wise compression fracture – Here the distal fragment to the hyoid bone by thyrohyoid ligament. It consists of hyaline will be bent inwards and the periosteum may be torn 203  MEDICOLEGAL ASPECTS OF HANGING Part III: Forensic Pathology Postmortem Hanging (Postmortem Suspension) Hanging could be a postmortem hanging also, in order to conceal and mislead a case of homicide as suicidal hanging. Differences between antemortem and postmortem hanging is shown in Table 15.2. Suicidal Hanging In India, hanging is a common mode of committing suicide among men. Table 15.2, highlights the differences between antemortem and postmortem hanging (postmortem suspension). Age is no bar for suicide by hanging. Author held an antopsy on a boy of 12 years who committed suicide for not able to get admission in a private school due to high fee. Partial hanging is almost diagnostic of suicidal hanging.4 Physically disabled, blind person, lame, amputated arms, or forearms – all have Fig. 15.6D: Mechanism of hyoid and thyroid cartilage fracture successfully committed suicide by hanging.4 in strangulation Homicidal Hanging on the outer aspect. It is possible that one or both the This is very rare. It is virtually impossible to hang a healthy adult horns may be fractured due to compression on one or unless beaten to unconsciousness or rendered helpless by alcohol both sides, with one horn fractured on to innerside and or drugs.1 Firstly, one may suspect homicide by virtue of the the other on to the outer side (Fig. 15.6B). injuries on the victim. Secondly, there may not be any struggle – Traction/Avulsion/Tug fracture – Here due to the powerful marks on the body except noose mark or possible contusions muscles attached to the upper and anterior surface of of the arms, inflicted while being forcibly restrained to hang. hyoid bone, it is drawn up and held rigidly (Fig. 15.6D). This may also be a fact when there is disproportion between Violent lateral or downward movements of thyroid victim and assailant, such as an adult and a child or a huge cartilage or pressure between the cartilage and hyoid man and a small woman etc. to rule out any violence that may bone can bring about the traction through thyrohyoid not be visible and to make sure that the individual was not ligaments resulting into this fracture of the hyoid bone. drugged. In every alleged case of suicidal hanging, a complete These fractures are usually with extravasation or blood in toxicological analysis must be performed.1 Homicidal hanging soft tissues around; need not be seen in all cases of antimortem may be suspected when following findings are observed in the hanging. It is said that circulation gets compromised during body hanged: hanging and hence no bleeding is seen even if the hanging is Knot of the ligature is exactly on the back of the neck antemortem.4,6 Mouth is gagged with cloth/paper Fracture of thyroid cartilage – Fracture of superior horns of thyroid Hands are tied on the backside of body cartilage is common like greater horns in hyoid bone and this Several injuries on the parts of body usually depends on state of ossification of these structures.4 All these are suggestive of struggle by the victim, being According to Polson, the incidence is 50 per cent of all handing attacked before hanged. However, tying of hands and feet may cases they studied. 7 However, common neck injuries are also be observed among victims of sexual asphyxial practices tabulated in Table 15.1. (refer below). Gagging, self suffocation, cutting of the wrists, Table 15.1: Common neck injuries in hanging deaths Neck structures injured Type of injury Probable courses Frequency Muscles of neck Haemorrhages bruising Direct pressure More common rupture (rarely) indirect stretching Blood vessels on ipsilateral Transeverse tear of intima Traction on the Rare side to the location of knot with haemorrhage blood vessel Hyoid bone Fracture Point of suspension and Common in age >30 years width of ligature Thyroid cartilage, sup. horns Fracture Location of knot More frequent common in Locating ligature age >30 years – Length of ligature – Possible swing – Indirect force by stretching of thyroid ligament and thyroid membrane 204  Chapter 15: Violent Asphyxial Death Table 15.2: Differences between antemortem and postmortem hanging (postmortem suspension) Characteristics Antemortem Postmortem Salivary dribbling mark at the angle of mouth, opposite side of knot +ve –ve Fecal/urinary discharge not very common –ve Ligature mark Direction oblique Circular Continuous/not noncontinuous Continuous Level in the neck high up above Low, below the level of below the level thyroid cartilage. thyroid cartilage. Parchmentisation +ve –ve Vital reaction +ve –ve Knot Single, simple, on More than one, granny one of the side of neck/ or reef type on rarely on chin the occiput/chin or occiput Tongue may or may not be +ve –ve protruded out, bitten at the tip Injuries Imprint abrasion/ Always +ve and +ve/ -ve and if Bruise with vital reaction +ve no vital reaction Elongation of neck +ve –ve PM staining Above ligature mark +ve –ve in lower limbs +ve +ve Glove-stocking like distribution +ve In dependent parts of body at the time of death and position at death Lung Surface Emphysematous bulla –ve +ve Evidence of Injury Self-infliction +ve (compatible) –ve Struggle evidence –ve +ve Tear of carotid artery intima +ve –ve Fracture of hyoid + ve (in long drop) Cyanosis Deeply +ve –ve/ faintly +ve Point of suspension Compatible with antemortem self-suspension Not so stabbing chest, self shooting, etc. may be noticed in the dead their neck on a cord or get entangled in a toy or mobile body of hanging, as hanging is often opted by these victims laced above their crib.12 as last measures who fail to die with all these techniques, may Among children—e.g. while playing Lasso. Here the neck mislead the case as homicidal hanging. of the child may get entangled in a ropes resulting in death due to asphyxia. Children while playfully acting hanging Accidental Hanging (especially judicial hanging scene), may actually be hanged Though the incidence of accidental hanging is not very common; to death.1,9 it may be reported among infants, children, adolescent and Among adolescent/adults—e.g. Sexual asphyxia, adults. popularly known also as “sex associated asphyxia, autoerotic Among infants—e.g. umbilical cord around the neck – this hanging, asphyxiophilia, hypoxiphilia, Kotzwainism, is also known as twisting of cord around the neck. This can masochistic phenomenon”, etc. These are asphyxial deaths cause the death of the fetus during birth or occasionally, in principle, caused by hanging; in which transitory anoxia immediately after birth from asphyxia due to accidental is intentionally induced to enhance sexual arousal produced strangulation.9 An infant may accidentally slip down in by masturbation.1,16 Within the victim’s view may be found between the side grills of a poorly designed crib, may die scattered pornographic literature supportive of deviant either because of constriction of neck with the body being practice. Usually this is practiced in secluded, private spots in suspended position9 or because of smothering when and in any accidents resulting in continuation of asphyxiation, trapped between a small mattress and the frame of the crib death is inevitable. This is more commonly practiced among with face wedged against the mattress.1 Rarely, infants may the adolescent boys in comparison to old aged men. get hanged accidentally from a pacifier suspended around Literature though reports few such incidences among 205  female,16-19 it is extremely rare. Individual may often be STRANGULATION Part III: Forensic Pathology dressed in female attire, particularly underwear. Neck is Definition usually found to be protected by soft cloth pads between Strangulation is a form of violent asphyxia caused by constricting skin and the noose preventing any visible ligature mark. Some the neck by some means, the force of constriction being other element of bondage or tying may also be seen in these victims than weight of victim’s body.1,3-7 of auto-erotism20 which may mislead the case as homicidal Explanation — here the application of pressure on the neck hanging unless the investigating officer is aware about the is either by bare hands, or by a ligature, or by any other material. fact. Victim of sexual asphyxiation may also be found with In this, asphyxia is caused by constriction of the neck without other methods of asphyxiation such as strangulation, or with suspending the body. plastic bag covering the head and face, etc.18 Neck structures involved in strangulation — Various neck structures involved during strangulation are presented Judicial Hanging diagrammatically in linedrawing Figure 15.7A. Cause of death in judicial hanging is due to injury to spinal Classification with explanation of each type, autopsy findings cord in the neck because of the fracture and dislocation of upper and medicolegal significance of strangulation are discussed below cervical vertebra C1,2 or 3 and contusion or transaction of the individually briefly. underlying cord. The knot is usually placed under left ear or less commonly, under the chin. A trap door on which he is Classification of Strangulation standing is sprung suddenly and the prisoner falls into the pit Depending on the means used, strangulation could be of several below, a specific distance or depth here being determined by types and they are - ligature strangulation, manual strangulation his height and weight. (throttling), mugging, bhansdola, garroting and palmar In perfectly performed judicial hanging, the victim abruptly strangulation. Each one is explained below briefly along with stops at the end of his fall when his head is jerked suddenly autopsy findings separately. The medicolegal aspects of and violently backwards, fracturing his spine, known as strangulation are also discussed in general. hangman’s fracture, a fracture through the pedicles of C2 with the posterior arch remaining fixed to C3, C1, the odontoid process Ligature Strangulation and anterior arch of C2 remaining in articulation with base of When a ligature material is used to strangulate the victim it is the skull. This injury pattern is caused by hyperextension and called ligature strangulation. Here the pressure on the neck is applied by a constricting band that is tightened by a force other distraction and results in injury of the cord at C2-3. This classic than the victims body weight.1,6,9 fracture does not occur always in hanging. According to Spence et all, in six cases of judicial hanging Postmortem Appearances studied by them, they observed fracture of the hyoid, the styloid External process, occipital bones, cervical body of C2 and transverse All findings are same as in hanging, except certain specific findings process of C1-3 and C5.13,14 in the neck as enumerated below (Fig. 15.7C). Lynching Ligature mark Lynching is hanging of a victim who may be criminal by a mob. Seen all around the neck. Thus it is homicidal hanging. The people who get angry by the Situated at the level of lower part of thyroid cartilage or offence committed by the accused, kill him publicly by hanging below it. to demonstrate the punishment given to him. This was common It will be running horizontally in South America, where black rapists were killed by angry white Few abrasions seen – finger nail marks when present are mob.9 The terminology lynching is more often used presently directed downwards and outwards. for any type of killing of a social offender, publicly by a mob. Other parts: Strangulation being usually homicidal, injuries due to struggle, known as struggle marks are often observed, as the Difficulties in Diagnosis of Death from Hanging victim usually makes all the effort to resent prior to getting Following may be difficult to explain whenever encountered in strangulated. These could be abrasions, scratches or abraded a body found hanged: contusions over face, arms and other parts of the body. Ligature running around the neck —victim might be killed first by strangulation and then hanged to simulate suicidal hanging. Presence of two-ligature marks—it might be an antemortem hanging case, but after few minutes of hanging, it might have slipped further down producing second ligature mark. Nail marks on the neck—it might look like manual throttling. But possibilities are that, the victim after getting hanged, made efforts to release the ligature around neck with his or her fingers and while doing so his or her own fingernails might have produced nail marks. Faint ligature mark—may be seen in dark skin complexion person. Injuries on the body—victim while inducing hanging might Fig. 15.7A: Diagrammatic representation of neck structures have got injured him or herself (wide supra). involved in strangulation 206  Chapter 15: Violent Asphyxial Death Fig. 15.7B: Effects of pressure on the neck in manual strangulation: Fig. 15.7D: Mannual strangulation (throttling) using both hands (1) Carotid sinus pressure – vagus nerve stimulation – cardiac arrest; (left) and one hand only (right) (2) Carotid artery blockage – unconsciousness; (3) Jugular vein blockage – congestion and haemorrhages; (4) Airway blockage – oxygen lack Manual Strangulation (Throttling) When bare hands are used to compress the neck and strangulate it is known as manual strangulation or throttling. The mechanism of death is by occlusion of the blood vessels supplying blood to the brain, i.e. the carotid arteries. Occlusion of the airway probably plays a minor role, if any, in causing death.1 Carotid sinus pressure, may result in vagus nerve stimulation resulting in cardiac arrest (vagal inhibition) (Fig. 15.7B). Autopsy Findings Signs of asphyxia are present. In addition, following specific findings are obvious in the neck: (Figs 15.7E to G). External Bruising of the neck – Bruising of the neck is due to the grasping of neck by the assailant. These bruises are usually circular, dark red or purplish in colour, and are about 1-2 cm in size. If the gripping fingers slide over the skin, bruises take up an elongated shape (Figs 15.7E to G). Fig. 15.7C: Classical features in strangulation Abrasions on the neck – The neck examination will show fingernail marks, which could be from both assailant as well as victim. They can be curved, semilunar or linear. If curved Internal they could be concave or convex due to the elasticity of skin Thyroid cartilage – usually fractured vertically in all and subcutaneous tissue. When one hand is only used, strangulations. thumbnail impression is seen on one side of the neck, while Hyoid bone – is usually not broken. However if seen, it is other four-fingernail marks are seen on other side of the neck seen in the greater cornu at the junction of outer one-third (Fig. 15.7D). When both hands are used, thumbnail impression with inner two-third, with the broken fragment displaced of both hands will be in the middle with rest of the four fingers outwards (see Fig. 15.6C). nail marks seen on either side of the neck (Fig. 15.7D). Bruising of the soft tissue and muscles of the neck is more However, if the thumbs overlap then midline impressions would common in strangulation than in hanging. It is by the ligature, be absent. Thus, the finger nail marks, are helpful in more so when a rough ligature is used, and there has been interpretation of the case giving opinion. struggle and resistance. Bruising of the subcutaneous tissue may be present even when there is no external marks on Internal the skin. However, brusing may be absent when the ligature If extensive pressure is used, it can lead to fracture of thyroid has been tightly secured and not removed until circulation cartilage, and inward fracture of greater cornu of hyoid bone stops.4 (see Figs 15.6C and D). 207 Part III: Forensic Pathology Figs 15.7E to G: Manual strangulation (throttling) findings in the neck. (E) Front view; (F) Left lateral view; (G) Right lateral view. Note: Bruises and abrasions of fingers and finger nails Mugging (Arm-Locks) Neck is compressed or squeezed by holding it between the crook of the elbow or knee. The attack is usually made from behind. Though a victim killed by this method shows signs of asphyxia, and other struggle marks, on examination neck will not show any evidence of violence, as the compression was affected by the soft muscles of the arm or leg.6,9 It may also be because the death is due to vagal inhibition.4 Bhansdola Neck is compressed between two bamboo sticks one held in front of the neck and the other behind it. This may also be induced by just one bamboo stick or a metal rod, compressing over the neck against the ground or wall. This may be even done by compressing the neck on the ground by a foot from the front.5,6,9 Garroting In this method a thin string is thrown around the neck of an unaware victim, from his back. The ligature material is then tightened rapidly with the help of two sticks tied at the free ends Fig. 15.7H: Execution of a criminal prisoner by garroting at of the string, so as to constrict the neck strongly. Bilibid Prison, Manila Note: The method is often used by Thagi’s in the past in India, to kill the travelers and rob their belongings in lonely places. assault, as it is common for an assailant to molest/ rape a In Spain, garroting was also said to be the official method of girl and then strangle her. Detailed examination of external execution of criminals9 (Fig. 15.7H). and internal genital organs, including vaginal washings for Palmar Strangulation chemical and microscopic examination, is performed Palmar strangulation is a combined from of violent asphyxia preferably.18 Finger nail scrapings and pubic and scalp hair where in smothering and strangulation are performed together. sample from the deceased should also be retained for possible In this, pressure on the neck is applied by both hands. When examination later at forensic science laboratory. base of the palm of one hand is used to compress over the front Ligature material – It is reported that in ligature strangulation of the neck, fingers of the same hand compress the mouth and anything which can be twisted may be used as a suitable nose, while the second hand is held over the fingers of the first ligature material. Ligatures used range from electrical cords, hand, reinforcing the strength of compression.4-6,9 neckties, ropes, and telephone cords to sheets and hose. The knot could be half knot, a full knot, a double or tipple Medicolegal Aspects of Strangulation knot. Appearance of ligature mark on the neck is subject Motive – Virtually all strangulations whether ligature or to considerable variation, depending on the nature of the manual are homicidal.1 There will be marks of violence, on ligature, amount of resistance offered by the victim, and the other parts of the body. amount of force used by the assailant. It may be faint and Sex incidence – Though in ligature strangulation, females barely visible, or absent in young children or incapacitated predominate as victims, it is not as much as reported in case adults, especially if the ligature is soft, for example, a towel, of manual strangulation. According to the studies reported and removed immediately after death. If a thin ligature is by DiMaio and DiMaio, the most common motive for manual used, there will be a very prominent deep mark encircling strangulation was rape, followed by domestic violence.1 Thus the neck, which will be yellow parchment-like initially and if the victim is female, carefully look for evidence of sexual turn brown later. 208  Suicidal Manual Strangulation is never reported. Manual self- as there are no specific findings. All that one finds is nonspecific Chapter 15: Violent Asphyxial Death strangulation is impossible, as pressure on the neck depends acute visceral congestion. It is only by analysis of circumstances on voluntary action, which is discontinued when the power leading up to and exclusion of other causes; one can determine of decision is obliterated with loss of consciousness.4,6,18 the cause of death.1 Suicidal Ligature Strangulation is not rare, but in these cases the ligature is sustained by ‘stay’ mechanisms such as SMOTHERING overlapping loop. Some of the methods adopted for suicidal Definition strangulation are described below:1,9 Smothering is a form of asphyxia caused by mechanical occlusion – One may go on giving turns of ligature material around of external air passages, viz. the nose and mouth by hand, cloth, his neck until he becomes unconscious. The death ensues plastic bag, duct tape or such other material. here prior to the turns of ligature getting untwisted to relax the constriction of the neck. Autopsy Findings – Another method is that after encircling the neck with a Following specific findings are usually seen: rope he may go on putting knots until he becomes Abrasions, bruises and lacerations - may be found around unconscious and dies. the mouth and nose in homicidal/accidental/suicidal – In this method one may lie down on the side of a cot smothering cases and they are: and tie a rope round his neck loosely and at the other – When hands are used, these abrasions are usually end of rope he will tie a weight. He then drops the weight crescent shaped nail scratches. down the cot. The length of the rope being shorter than – There may be fracture of the nasal cartilage with bleeding height of the cot, he gets strangled due the weight of from nose/ mouth (occasionally) the stone hanged. – Abrasions may not be seen if a soft material such as cloth, a pillow, etc. is used. However depression and bleeding SUFFOCATION from the nose may be seen in such cases. Definition – At times due to the friction over teeth, there will be Suffocation is a form of asphyxia caused by lack of oxygen in frenular tears, abrasions, contusions or lacerations seen the atmospher or by mechanical obstruction to the air passages on the inner aspect of lips. Teeth may also be loose and by mechanical means other than constriction of the neck and dislocated at times with tearing of gum tissue. drowning. – All above findings are more common and extensive when the face is pressed against a hard surface. Classification – Body may show struggle marks in other parts of the body, There are several forms of suffocation in general and they are more often noticed in homicidal smothering than in enumerated and discussed individually below: accidental or suicidal type. Entrapment In accidental smothering — by fall over heap of dust, Environmental suffocation flour, etc, stains of these materials may be present Smothering outside as well as inside the face, mouth and nose. Choking In case of overlaying by mother’s breast — the delicate Traumatic asphyxia tissue of nose and face of the infant will be compressed Burking and pale (refer below). Suffocating gases. In cases of sexual asphyxia — the pornographic pictures around, exposed genitals or total nudity of the victim, ENTRAPMENT wearing apparels or inner garments of opposite sex, This is due to inadequate oxygen in the environment. These methods of inducing asphyxia, private or isolated room, are exclusively accidental in nature. In entrapment, people find etc. act as evidence in favour. themselves trapped in an airtight or relatively airtight enclosure. In suicidal smothering there will be some of the pressure Initially there is sufficient oxygen to breathe. However, as effects but no remarkable injuries detected. respiration continues, they exhaust it soon as time passes and then asphyxiate. E.g.: A child getting trapped in a discarded Note: The above findings may be missed, unless looked for. refrigerator. Fortunately, this specific form of death by entrapment is rare these days, as modern refrigerators do not Medicolegal Importance have a latch system of locking and can be pushed open from These deaths are usually either homicidal or suicidal, but within. Suicide and homicide by entrapment are rare, but do very rarely accidental.1 occur.1,6,18 Accidental smothering: It is common in alcoholics, intoxicated or unconscious person ENVIRONMENTAL SUFFOCATION lying in prone position, or may fall or roll over and bury Here the individual inadvertently enters an area where there in bins of flour, heap of mud or such other material. Similar is gross deficiency of oxygen, e.g. mountaineering – where people may be the case with epileptics, during the attack of fit.9 climb to reach high altitudes, certain profession demanding After birth an infant may die from smothering if it is born entering into the underground chambers, petrol or diesel tanks with membranes covering the nose and mouth (cul-de-sac). or tanker carriages, unused deep wells, underground sewage Children may get suffocated while playing with plastic bags drain system, etc. for cleaning purpose, may get suffocated due over the face or head or on entire body (rarely). to lack of oxygen or presence of irrespirable gases in it.1,6,9,15 Sexually perverted individuals may cover/envelop the head In death due to entrapment and environmental suffocation, in plastic bag during the autoerotic experiences and get killed the cause of death cannot be determined by autopsy alone, accidentally. 209  Overlaying Sucking of a piece of balloon to puff it or inflate it inside Part III: Forensic Pathology It is form of accidental smothering of an infant by the mother the mouth may result in occlusion of larynx when sucked sharing the same bed with the child, may roll over it during into it accidentally when the grip on the balloon is not firm.9 sleep and occlude the air passages by her breast which the infant Mechanism of Choking may be suckling, developing asphyxia and death. Overlaying, Usually any object in the air passages excite violent coughing the accidental death by smothering caused by a larger individual out, but if this is not successful in expelling the object out, choking sleeping on top of an infant is a cause of death that has been results. documented for centuries. The hazard of death has been reported Choking and size of the object—in inducing choking size to be greater in infants less than 5 months of age but may occur of the object is not important. Even an object smaller than in children up to the age of 2 years. When an adult or older the lumen of respiratory tract can bring about reflux spasm child rolls on top of an infant, mechanical asphyxia results. The of air passages with fatal consequences. face may be pressed into the mattress or into the body of the Choking in an epileptic, during the attack, with the tongue sleeping adult or older child. The infant’s air may be expressed, falling against the posterior pharyngeal wall, blocks the entry and he or she is unable to cry due to pressure on the thorax of air and results in choking. and the inability to inhale. Some pathologists and investigators believe that the victims of overlaying have no pertinent physical Causes of death in choking Death is usually due to any one findings at autopsy and that any injury is indicative of inflicted of the following: trauma. Others believe that one may see contusions and Asphyxia abrasions from overlaying in and of itself. Wedging is another Vagal inhibition (occasionally) form of accidental mechanical asphyxia that may have negative Laryngeal spasm autopsy findings. The prevalence of bruising, contusions, or facial Autopsy findings Apart from routine autopsy findings of and ocular petechiae is not clear.9,10 asphyxial death, following specific findings are observed: Medicolegal importance—though overlaying is not a Presence of the foreign object that produced choking will common condition, these cases are likely to be referred as victim be found in the respiratory tract, when dissected properly. of sudden infant death syndrome (SIDS). It may also be a case If the victim was an epileptic, the tongue must be specially of infanticide. The condition may also be reported when a child examined for its position and the presence or absence of and adult are sharing same bed.9 bruising or bite marks. It is usually found on posterior pharyngeal wall with injuries. Homicidal Smothering Homicidal smothering of adults is very rare and also difficult, Medicolegal Importance unless the victim is weak, or stupefied by drugs or drinks 1. Choking is usually accidental, more common in children, like alcohol as seen in burking. Some of the methods of who play, laugh, talk, etc. while eating. homicidal smothering are by: 2. Cafe coronary: This is a condition of accidental choking – Pressing the face and the nose by hand, towel, pillow, where a bolus of food produces complete obstruction of the etc. larynx. It is called so because it mimics heart attack. – Tying plastic bag or such other materials around the Causes: It could be any one of the two causes enumerated mouth and nose. below: – Pressing the face of the victim over ground. – Suppressed gag reflex due to gross intoxication with Suicidal Smothering alcohol or large doses of tranquilizers in mental Suicidal smothering by one’s own hands on him or her is institutions or hospitals. impossible. However some of the methods attempted are – Reflex cardiac arrest as a consequence of stimulation of by: laryngeal nerve endings. – Tying a plastic bag around the head covering the mouth and nose and tightening it by applying multiple knots until the person loses consciousness. – Tying a pillow in front of the face with application of several knots until loses consciousness. CHOKING Definition Choking is a form of asphyxia caused by mechanical occlusion within various sites of upper air passages (Fig. 15.8) by foreign object. These objects may be: A solid object like a metallic coin, edible fruit seed, toffees, candies, spherical solid sweets, etc. A food particle like bolus of rice particles, fish and any other animal bone, etc. Piece of cloth like handkerchief, sari or dhoti material stuffed into the mouth tightly occluding the air passages. Tongue of the person who