Autopsy forensic postmortem examination.

autopsy postmortem examination of dead bodies for forensic analysis

1. Autopsy

2. Autopsy The Medicolegal or Forensic Autopsy P erformed on the instructions of the legal authority I n circumstances relating to suspicious, sudden, obscure, unnatural, litigious or criminal deaths Clinical or Academic Autopsy P erformed with the consent of the relatives of the deceased to arrive at the diagnosis of cause of death Necropsy E xamination of the dead body (postmortem examination) with a view to searching primarily for the cause of death

3. Medicolegal Autopsy- Objectives To determine identity of the deceased cause of death mode of dying and time since death wherever possible To demonstrate external and internal abnormalities, malformations, disease, etc. external as well as internal injuries. To obtain samples of tissues/body fluids for examination/analysis wherever necessary. photographs and video films wherever necessary. In case of newborn infants, to determine the issue of live birth and viability. I n booking the criminals / protecting the innocent suspects

4. Guidelines for Autopsy A medicolegal autopsy is to be carried out at the behest of the appropriate legal authority Performed only at the authorised centre Preferably be done by a person of experience and knowledge Preferably be conducted under natural sunlight Formal identification of the dead body must never be omitted. Avoid delay as far as possible. No unauthorised person should be permitted to enter the mortuary. No police official should be present while the autopsy is being conducted. All the details should be noted there and then in the postmortem register. Always hand over the report and other specimens/tissues/articles, etc., immediately after conducting the postmortem. Never indulge in delaying the things .

5. EXAMINATION OF CLOTHING Clothing and their contents need detailing (style, fabric, colour , print/pattern and labels/marks, etc.) Handing over to the police in a sealed packet after putting signatures Contents of the pockets, documents, articles, ornaments, etc., all provide clue towards identification removed gently, taking care to avoid contamination or loss of any trace evidence Hair, fibres , fragments of paint, glass must be collected and handed over to the police after due sealing Garment and photographs be obtained to demonstrate stains, tears, cuts or other effects upon the clothing. If clothing is wet or smeared with mud/soil, etc., it should be air-dried and not heat-dried.

6. EXAMINATION OF THE BODY External Examination Internal Examination

7. External Examination In all cases of sexual assault vaginal and anal swabs are taken Note the presence of stains on the skin from blood, mud, vomit, faeces etc. Note the presence of signs of any disease. Face: examined for the frothy fluid at the mouth & nose, cyanosis, petechial haemorrhages , pallor etc. Eyes: Examined for the condition of eyelids, conjunctivae, colour of sclera & pupils, contact lenses, petechiae & periorbital tissue for extravasation of blood.

8. Neck: Examined for bruises, fingernail abrasions, ligature mark or any other abnormalities. Thyroid: Size, nodularity Lymph nodes: Cervical, axillary, inguinal. Thorax: Symmetry, general outline. Breasts: Size, masses. Abdomen: Presence or absence of distension or retraction, striae gravidarum. Back: Bed sores, spinal deformity.

9. Natural orifices: Mouth, nostrils, ears, vagina etc. should be examined for injuries, foreign matter, blood etc. The hands should be examined for injuries, defence wound, electric mark etc. Look for needle puncture marks in the arms, buttocks etc. External injuries such as abrasions, bruises, lacerations, burns, scalds etc. should be examined systematically with full details to include exact site, length, breadth, direction, position, margins, base and extent. Determine whether they are caused before or after death & their time of infliction.

10. PRIMARY SKIN INCISIONS I -shaped Y-shaped Modified Y-shaped

11. I –shaped incision Extending from the chin straight down to the symphysis pubis and avoiding the umbilicus Most common method followed.

12. Y-shaped incision Begins at a point close to the acromion process → extends down below the breast & up to xiphoid process → make a similar incision on the opposite side → now make a straight incision from xiphoid process to symphysis pubis Desirable in those cases (especially females) where it is customary to keep a dressed body for viewing after death.

13. Modified Y -shaped Incision from suprasternal notch to symphysis pubis in the midline → extend the incision from suprasternal notch up to the centre of clavicle on both sides. Then passes upwards over the neck behind the ear

14. Methods of Dissection of Organs Virchow’s Methods Rokistansky’s Method Letulle’s Method Ghon’s Method

15. Types Post-mortem examination Medical /clinical/ pathological / hospital autopsy. Anatomical autopsy Psychological autopsy Virtual Autopsy Medico-legal autopsy

16. Medical/ Academic Autopsy: Carried on a patient who dies in a hospital during course of treatment. OBJECTIVES 1. To determine the cause of death. 2. To confirm or establish the clinical diagnosis 3. To evaluate the effects of treatment given during life. 4.Performed by a pathologist with consent of relatives.

17. Anatomical Autopsy It is performed to study normal structure of human body. Mostly on unclaimed dead bodies Anatomist and medical students perform this.

18. Psychological Autopsy It is undertaken on alleged cases of suicide to know about the mental status of deceased at the time of death. It is performed to know about : Background of person His habits, mental status, personality, character. Relation to others Sources of collection of information are Family members friends professional colleagues teachers physicians

19. Postmortem Examination Examination of external surfaces of corpse by inspection incision without for giving systemic examination. However, specimen of body fluids like blood bile urine may be collected.

20. Virtual Autopsy It is a postmortem examination without compromising the integrity of the body, even without collection of sample. Due to some reason or disease the autopsy of dead body is not possible then by the help of radiological examination we can detect the cause of death.

21. Medico-legal Autopsy Essential examination of dead body, to rule out or establish foul play in death. It is performed in pursuance of law to establish the cause and manner of death and also to establish or rule out foul play.

22. Embalming composition

23. Exhumation L awful disinterment or digging out of a buried body from the grave There is no time limit for exhumation in India OBJECTIVES Identification Establishing cause of death Second autopsy

24. PRECAUTIONS Carried out under the orders of the appropriate authority. District Magistrate/Sub-Divisional Magistrate/Executive Magistrate are empowered to order for the exhumation. Body is exhumed under the supervision of a magistrate in the presence of a doctor Exhumation should preferably be carried out during early morning hours. Identification of the grave is important.

25. SECOND AUTOPSY The body is buried after due autopsy but discrepancy arose after sometime, may be due to public hue and cry or some political overtones doctor must obtain all the available documents relating to the case especially the first autopsy report interpretation of findings of a second autopsy, performed on a previously autopsied exhumed body, is extremely difficult due to various artefacts of burial and exhumation and the alterations resulting from the first autopsy.

26. Obscure Autopsy Negative autopsy

27. Death The cessation of life C easing to exist: a total stoppage of circulation of the blood and a cessation of animal and vital functions consequent there upon, such as respiration, pulsation, etc. Irreversible damage to the brain often occurs during the short period when breathing/circulation has been suspended. Serious permanent impairment can occur with only 4–6 minutes of oxygen deprivation, Total loss of function may often occur when deprivation exceeds 6–10 minutes.

28. Causes of brain-stem damage Irreversible causes Hypoxia Trauma Illness or toxic insult Reversible causes Intoxication Depressant drugs Muscle relaxants Primary hypothermia Hypovolemic shock Metabolic or endocrinal disturbances

29. The structural and functional damage of brain-stem Dilated fixed pupils, not responding to sharp changes in intensity of incident light. Absence of motor responses within the cranial nerve distribution on painful stimulation. Absence of corneal reflexes. Absence of vestibulo -ocular reflexes. Absence of gag reflex or reflex response to bronchial stimulation by a suction-catheter passed down the trachea. Absence of spontaneous breathing.

30. Considering the death to be a permanent and irreversible cessation of functions of the three interdependent vital systems of the body

31. Somatic and Molecular Deaths Somatic Death: Extinction of personality or the death of the body as a whole Soma means body W hen there is cessation of vital processes of the body. This is referred to as somatic death (systemic or clinical death) Molecular death: Somatic death is followed by progressive disintegration of body tissues and is called as cellular or molecular death. In the absence of circulation and respiration, different cells die their molecular deaths

32. Molecular Death Brain cells:- 5 min Muscles:- > 1hr. Liver, kidney, Heart Blood cells, cornea:- > 5 hr Fibrous tissue (bone, cartilage)

33. Suspended Animation (Apparent Death) Voluntary act (death trance) Hypothermia Bodies removed from water Newborn infants Electric shocks Vagal inhibitory reflexes

34. Mode of Death A bnormal physiological state that existed at the time of death. Three modes of death depending upon the system most obviously involved: Coma- failure of functions of brain. Syncope- failure of functions of heart. Asphyxia- failure of respiratory system.

35. Manner of Death D esign’/fashion in which the cause of death came into being. Natural If death results from some disease Violent/unnatural If death results by injury Violence may be accidental, suicidal or homicidal in origin

36. Mechanism of Death P hysiological derangement or biochemical disturbance in relation to death. Includes such entities like metabolic acidosis and alkalosis, sepsis, toxemia or paralysis, etc.

37. Cause of Death I njury, disease, or combination of the two that initiates a train of physiological disturbances, resulting in the termination of an individual’s life. Immediate cause of death Disease or injury present at the time of death that caused person’s death P roximate cause of death Original natural disease process, injury, or event that led to a string of uninterrupted train of events (time interval may be spread over weeks, months, or even years), that eventually led to the individual’s death.

38. Post-Mortem Changes

39. IMMEDIATE SIGNS OF DEATH Insensibility and loss of voluntary power Cessation of respiration Cessation of circulation Immediate signs of death deserve caution

40. EARLY CHANGES AFTER DEATH Facial Pallor and Changes in the Skin Primary Flaccidity of the Muscles Changes in the Eye Loss of corneal reflex Opacity of the cornea Flaccidity of the eyeball State of the pupils Changes in the retinal vessels Algor Mortis (Postmortem Cooling) Livor Mortis (Postmortem Hypostasis) Rigor Mortis (Postmortem Stiffening)

41. Facial pallor

42. Loss of corneal reflex

43. Opacity of cornea

44. Flaccidity of eyeball

45. Tache noire

46. Algor Mortis (Postmortem Cooling) Body starts losing heat after death Recorded by rectal temperature Usual temperature of a healthy adult 98.4° F (37° C) Rectal temperature of 21° C (70° F) is presumptive evidence of death

47. Factors affecting PM cooling Temperature of the body at the moment of death Temperature difference between the body and the surroundings Body-built (the size factor) Air current and humidity Postmortem caloricity Clothing and coverings

48. Livor Mortis (Postmortem Hypostasis) Postmortem hypostasis/ postmortem lividity/ postmortem staining/ suggillations/ vibices. Hypostasis means ‘passive congestion of an organ or part’. With the cessation of circulation at the time of death, the blood obeying the law of gravity gravitates into the toneless capillaries and venules of the ‘rete mucosum ’ in the dependent parts of the body and settles into the lowest available parts of the body. Passive pooling of blood into the dependent areas of the body, imparting purplish or reddish-purple discolouration

49. Postmortem hypostasis

50. Time of Appearance Generally, starts appearing within an hour after death Purplish blotches → large area of reddish-purple discolouration . Usually complete in 6–12 hours

51. Distribution of hypostasis Depends upon the posture of body after death Least at areas of contact flattening In case of hanging- on dependent lower limbs, surrounding genitalia, hands and distal portions of the arms. In case of drowning- on face, upper part of chest, hands, lower arms, feet and lower legs

52. Fixation of Postmortem Staining When hypostasis is well-developed and gets fully established There will be no change in the distribution of hypostasis on altering the position of the body as the blood gets coagulated Physical factors for ‘fixation of hypostasis’ Inability of blood to flow in well-developed areas of lividity as compared to quick changes observed in change of position of the body during the first few hours of death. R igor mortis also makes the appearance in the body.

53. Colour of the Hypostasis Depends upon the state of oxygenation at about the time of death. Hypoxic states -darker tint due to presence of reduced haemoglobin Hypothermia -pink due to presence of much of oxyhaemoglobin Cherry-pink or cherry-red -poisoning by carbon monoxide or hydrocyanic acid Chocolate or coffee-brown - poisoning by potassium chlorate, potassium bichromate or nitrobenzene, aniline Dark brown -poisoning by phosphorus. Bright pink patches -refrigerated dead body show bright pink patches of oxyhaemoglobin

54. Rigor Mortis (Postmortem Stiffening) Cadaveric rigidity Stiffening of the muscles after death. Three phases Primary flaccidity o ccurs immediately after somatic death muscles are able to respond to electrical or chemical stimuli. Rigor mortis – Development of rigidity no longer any response to the electrical or chemical stimuli Secondary flaccidity- stage of resolution rigor passes away coincides with the onset of putrefaction

55. Rigor mortis

56. Stages of onset First phase: muscle remains in a normal state Sufficient ATP to permit the dissociation of the actin–myosin cross-bridges. rate of ATP depletion will depend upon its content and on the rate of ATP hydrolysis at the time o Second phase: ATP content of the muscle falls below a critical level, the cross-bridges remain bound and the muscles tend to turn into viscous, inextensible dehydrated stiff gel like state that accounts for the onset of rigor mortis. state is still reversible by addition of ATP or O2.

57. Third phase: Rigidity becomes fully developed and irreversible. Fourth phase: Phase of Resolution Rigidity disappears and the muscle becomes limp and loose. Denaturation process due to development of enzymes in the dead muscles Dissolve myosin by a process of autodigestion

58. Time of Onset and Duration Apparent in about 1–2 hours after death G ets well-established in the entire body in about 9–12 hours Maintained for about 12 hours Gradually passes off in the same order as it appeared. In Northern India, the usual duration of rigor mortis 18–36 hours in summer 24–48 hours in winter.

59. Order of Appearance and Disappearance Appear first in the muscles of the eyelids by 1–2 hours of death Face and neck, lower jaw Trunk and arms, abdomen Lower limbs

60. Factors Influencing Onset and Duration Temperature Influence of nature of death Condition of the muscles before death Influence of central nervous system Age

61. LATE CHANGES AFTER DEATH Putrefaction or Decomposition Autolysis Bacterial Action Development of Foul-smelling Gases Skeletonization Adipocere

62. Autolysis Softening and liquefaction that occurs in a tissue even under sterile conditions B y digestive action of the enzymes released from the cells after death Prevented if freezing of tissues Parenchymatous and glandular organs Intrauterine maceration of foetus in the uterus occurs from aseptic autolysis Softening and even rupture of the stomach and lower end of the oesophagus

63. Bacterial Action Microorganisms- both aerobic and anaerobic Bacteria Inhabiting the body From the respiratory tract Open skin wounds Produce enzymes that lyse carbohydrates, proteins and fats Break down the various tissues.

64. L ecithinase P roduced by the Clostridium welchii , which hydrolyses lecithin present in cell membranes including blood cells Responsible for producing haemolysis of blood Helps in postmortem hydrolysis and hydrogenation of body fat. Putrefactive activities are optimal at temperatures between 70° and 100° F

65. Sign of putrefaction A ppearance of greenish discolouration of the skin of the anterior abdominal wall R ight iliac fossa Area is against the caecal region, which is rich in bacteria and fluid contents. Due to the conversion of haemoglobin into sulphmet-haemoglobin by the action of sulphuretted hydrogen diffusing from the intestines into the tissues. A ppears between 12 and 18 hours in summer 1–2 days in winter M ore appreciated upon the fair skin.

66. Marbling Anterior abdominal----entire abdominal wall ------adjoining parts of the external genitalia----chest---neck, face, arms and legs Green----purple -------dark-blue------------ultimately coalesce together Intestines -----venous system---blood haemolysed ----stains the vessel walls----gives marbled appearance Marbling of skin becomes prominent in about 36–48 hours

67. Development of Foul-smelling Gases Body begins to emit a nauseating smell owing to gradual development of gases of putrefaction. Gases are noninflammable in the initial stages Hydrogen sulphide at later stage C auses abdomen swelling 24 to 48 hours after death, gases collect in the tissues, cavities and hollow viscera under enormous pressure Causes bloating and distortion

68. Skeletonisation Body exposed to air may get skeletonized in about 2–4 weeks Fe w days if the body is attacked by ants, flies, dogs, jackals, etc. Prolonged if the body remains relatively protected/ concealed Differ from body to body, environment to environment one part of the same body to another O ne part of the body may be mummified, while the rest may show liquefying putrefaction

69. Factors Influencing Putrefaction Temperature of the atmosphere Immersion in water Access of air and light Burial under earth Cause of death State of the body Clothing upon the body Age and sex

70. ADIPOCERE Saponification Changes- Soft, greasy material, looking pale-white or cheese-like Becomes hard, dry, brittle and yellowish when old or exposed to air Odor- Rancid or sweetish Process- Hydrolysis and hydrogenation of body fats after death by the action of bacterial enzymes Main constituent _palmitic acid Prominence - Subcutaneous fats of cheeks, breasts, buttocks and abdomen Duration of onset- 3 months to 1 year

71. MUMMIFICATION Change- Drying and desiccation of the tissues occurs instead of liquefaction Causes- Deprivation of moisture, which inhibits proliferation of putrefying microorganisms. Free circulation of air around the body. Warm dry Atmosphere Features- Skin becomes dry, leathery and looks blackish-brown, clinging firmly to the body frame Hair on the scalp and the skeletonized body features are well-preserved body becomes stiff and brittle

72. Burnt bone analysis Causes: Fire victims in vehicle accidents M ass disasters H ouse fires Homicides where the victim’s body is purposely cremated and destroyed by the perpetrator Heat-induced fragmentation of burnt bones followed by artificial crushing

73. Burnt bone analysis Changes- Burning causes physical and chemical properties change Cause difficulties in forensic identification tests Physical changes : Deformation and fragmentation due to heat-induced shrinkage, Alter the morphological indicators that are critical for anthropometric analysis of species, sex, age, and stature estimation. C hemical changes- due to combustion and pyrolysis of chemical substances. Degree of modification increases with rising temperatures Degradation of DNA

74. Coloration of burnt bones Bone changes color drastically when it is burnt. Degree of bone coloration also varies with burning time, and a long period of burning results in more severe color alteration Anaerobic burning conditions delay the coloration process. Yellow-brown at 200°C Dark brown-black at 300°C–400°C A sh-like gray at 500°C–600°C Chalk-like white at excess of 700°C

75. Weight change in burnt bones Bone weight is reduced because of water vaporization and combustion of organic materials R eleases of carbon in form of carbon dioxide. Bone composition: 14% water and 24% organic matrix (by weight), 62% bone mineral Complete cremation of a human body leaves ~ 2,000 and 3,000 g of cremated female and male bones

76. Deformation of burnt bones Shrinkage and subsequent significant deformation causes problems for anthropometric tests Shrinkage continues even after weight reduction has ceased, the density of the compact bone increases at higher temperature (>500°C) and this results in bone hardening. Shrinkage mechanism produces cracks in the burnt bone

77. DNA in burnt bones Unevenness of burning in casework, even within a single bone, cannot be ignored The portion chosen for DNA extraction might have been exposed to a lesser degree than the dominant area used for classification of burn coloration

78. Advanced technology Micro-CT imaging technique: Enables to obtain not only surface layer three-dimensional shapes of fragmented bone but also its corresponding sliced histological image without any destructive preparation of fragile, severely burnt bone.