Asphyxial deaths, thermal and electrical injuries

16 NEET-PG practice questions on Asphyxial deaths, thermal and electrical injuries, part of Forensic Medicine. The first 16 are below; the first 5 with answers and explanations (tap Show answer after you have chosen), the rest in Learn with a free account.

1. Question 1 · Easy

   A 30-year-old electrician in Coimbatore collapses and dies after touching a live 230 V household wire. On his right palm is a small, round, greyish-white, crater-like lesion with raised edges and a pale halo around it. What is this lesion called?

   1. ACrocodile-skin burn
   2. BJoule burn (electric mark)
   3. CContact flame burn
   4. DLichtenberg figure

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   Answer: B · Joule burn (electric mark)

   The electric mark, or Joule burn, forms at the point where current enters through firm contact. Heat from the current at the high-resistance skin produces a small, round, grey-white crater with raised margins and a pale areola from local vessel spasm. It is the most important external sign of low-voltage electrocution, so the hands and points of contact must be searched carefully. Crocodile-skin burns follow high-voltage arcing, and Lichtenberg figures follow lightning.

   • A: Crocodile-skin burns come from high-voltage arcing over a wide area.
   • C: A flame burn causes blistering and singeing, not a pale crater with raised edges.
   • D: Lichtenberg figures are fern-like marks seen after lightning.

2. Question 2 · Medium

   A 10-year-old girl slips into a freshwater irrigation canal in Punjab and is pulled out dead within a few minutes. The autopsy surgeon explains the classically taught mechanism of death in freshwater drowning to the police. What is it?

   1. ALaryngeal spasm without water entering the lungs
   2. BHypertonic water drawing plasma into the alveoli
   3. CHaemodilution, haemolysis and hyperkalaemia causing VF
   4. DCold water causing reflex vagal arrest

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   Answer: C · Haemodilution, haemolysis and hyperkalaemia causing VF

   Fresh water is hypotonic, so large volumes are absorbed from the alveoli into the circulation, causing hypervolaemia and haemodilution. Red cells swell and lyse, releasing potassium, and the hyperkalaemia with hypoxia leads to ventricular fibrillation, which explains the rapid death classically described in freshwater drowning. In seawater drowning, hypertonic water draws plasma into the alveoli, causing pulmonary oedema and haemoconcentration, and death is slower. Modern studies show that hypoxia is the main cause in both, but the classical contrast is still taught.

   • A: Laryngeal spasm without aspiration describes so-called dry drowning, not the classic freshwater mechanism.
   • B: Hypertonic water drawing plasma into the lungs describes seawater drowning.
   • D: Reflex vagal arrest (immersion syndrome) causes death without features of drowning.

3. Question 3 · Easy

   A 19-year-old student is found hanging from a ceiling fan in her hostel room in Kota, suspended by a dupatta tied with a knot behind the left ear. Which ligature mark is typical of hanging?

   1. AHorizontal, complete, at the thyroid cartilage
   2. BHorizontal, complete, below the thyroid cartilage
   3. COblique, incomplete, above the thyroid cartilage
   4. DOblique, complete, below the thyroid cartilage

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   Answer: C · Oblique, incomplete, above the thyroid cartilage

   In hanging, the body weight pulls the ligature up under the jaw, so the mark runs obliquely upwards towards the knot, lies above the thyroid cartilage and is incomplete, with a gap at the knot. In ligature strangulation, the ligature is pulled tight around the neck, giving a horizontal, complete mark usually at or below the thyroid cartilage. A soft, broad ligature such as a dupatta may leave only a faint mark. The ligature should be preserved with its knot, cut away from the knot, for the police.

   • A: A horizontal complete mark points to strangulation, not hanging.
   • B: A horizontal complete mark below the thyroid cartilage is typical of ligature strangulation.
   • D: A hanging mark is incomplete at the knot and lies above the thyroid cartilage.

4. Question 4 · Medium

   A 32-year-old man is found hanging from a roof beam in his house in Meerut; the police ask the autopsy surgeon whether he was alive when he was hanged. Which finding is the most reliable sign of hanging during life?

   1. AHypostasis in the legs and hands
   2. BA tongue protruding between the teeth
   3. CA grooved ligature mark on the neck
   4. DDried saliva dribbling from the mouth

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   Answer: D · Dried saliva dribbling from the mouth

   Dribbling of saliva from the angle of the mouth on the side opposite the knot, running down the chin and onto the chest, is regarded as one of the most reliable signs of antemortem hanging. Pressure of the ligature stimulates the salivary glands, which can happen only while the person is alive. A ligature mark, protrusion of the tongue and hypostasis in the lower limbs can all occur when a dead body is suspended. Its presence should be recorded and photographed before the body is handled.

   • A: Hypostasis in the legs only shows that the body hung for some hours after death.
   • B: The tongue may protrude in post-mortem suspension and in other asphyxial deaths.
   • C: A ligature mark can be produced by suspending a dead body.

5. Question 5 · Easy

   A 40-year-old farmer working in a paddy field in Palakkad during a thunderstorm is found dead. Over his chest and shoulders is a reddish, branching, fern-like pattern on the skin, and the zip of his trousers is partly fused. What is the skin pattern called?

   1. ATache noire
   2. BJoule burns
   3. CMarbling of decomposition
   4. DArborescent (Lichtenberg) marks

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   Answer: D · Arborescent (Lichtenberg) marks

   Arborescent or Lichtenberg marks are red, branching, fern-like patterns on the skin after a lightning strike. They are thought to arise from the passage of current along the skin and are transient, fading within hours to a day or so in survivors. Other signs of lightning include fusion or magnetisation of metal objects, singeing of hair and torn clothing. The scene and weather history are as important as the body findings in deciding the cause of death.

   • A: Tache noire is drying of the sclera in open eyes after death.
   • B: Joule burns are small crater-like marks of low-voltage contact.
   • C: Marbling is a post-mortem branching of discoloured veins, seen days after death.

6. Question 6 · Medium

   Several people die in a crowd crush at the gate of a temple festival in Andhra Pradesh. The bodies show deep purple-blue congestion of the face, neck and upper chest with numerous petechiae, subconjunctival haemorrhages and a sharp line of demarcation at the upper chest; the neck has no marks. What is the cause of death?

   1. ALigature strangulation
   2. BChoking on a foreign body
   3. CTraumatic asphyxia
   4. DSmothering

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7. Question 7 · Medium

   A 23-year-old woman is brought to a district hospital in Uttar Pradesh with kerosene stove burns. The burns cover the whole of both lower limbs and the front of the trunk, while the back, perineum, arms and head are spared. Using the rule of nines, what is the burnt body surface area?

   1. A54%
   2. B63%
   3. C36%
   4. D45%

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8. Question 8 · Medium

   The body of a 27-year-old woman is found on her bed in Rohtak; her husband says she hanged herself and that he cut her down. There is a horizontal, continuous mark of uniform depth encircling the neck below the thyroid cartilage, with bruising of the strap muscles, a fractured thyroid cartilage, and a congested face with petechiae. What is the most likely cause of death?

   1. AThrottling
   2. BHanging
   3. CSmothering
   4. DLigature strangulation

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9. Question 9 · Medium

   A decomposing body of a 40-year-old man is recovered from the Brahmaputra four days after he went missing. His relatives suspect he was killed and thrown into the river. Which investigation best helps establish that he drowned while alive?

   1. ADiatoms in the femoral bone marrow
   2. BDiatoms in the stomach contents
   3. CWater in the stomach and duodenum
   4. DGettler's chloride test of heart blood

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10. Question 10 · Medium

    An 8-year-old boy is pulled out of a village pond in West Bengal within an hour of falling in, and is declared dead. Fine, white, lathery froth is coming from his mouth and nostrils; it reappears when wiped away and when the chest is pressed. What does this finding indicate?

    1. AThe body was placed in water after death
    2. BHe was alive when he entered the water
    3. CDecomposition has already started
    4. DHe died of an epileptic fit on land

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11. Question 11 · Medium

    A 24-year-old woman is found dead in a rented room in Bengaluru. The front of her neck shows several small crescent-shaped abrasions and round bruises on either side of the larynx, with more bruises on the left side than the right. There is no ligature mark. The face is congested with petechial haemorrhages in the conjunctivae. What is the most likely cause of death?

    1. AHanging
    2. BLigature strangulation
    3. CThrottling (manual strangulation)
    4. DSmothering

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12. Question 12 · Medium

    A 24-year-old woman married three years ago dies of 90% burns in her husband's house in Patna; the husband says her saree caught fire while cooking, but her parents allege harassment for dowry. Who should hold the inquest into her death?

    1. AThe Chief Medical Officer
    2. BA coroner
    3. CAn Executive Magistrate
    4. DThe police officer in charge

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13. Question 13 · Hard

    The body of a 30-year-old woman is recovered from a burnt hut in a village near Nashik. Her husband says the hut caught fire while she slept. At autopsy: 1. Soot is present in the trachea and bronchi below the vocal cords. 2. Carboxyhaemoglobin in heart blood is 40% saturation. 3. The limbs are flexed in a pugilistic attitude. 4. The hypostasis is cherry pink. Which findings indicate that she was alive when the fire started?

    1. AFindings 1, 2 and 4 only
    2. BFindings 1, 2 and 3 only
    3. CFindings 1, 2, 3 and 4
    4. DFindings 1 and 2 only

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14. Question 14 · Hard

    A 35-year-old woman is found dead, wet, beside a plastic bucket in her bathroom in Thrissur. An electric immersion water-heater rod lies in the bucket and the switch is on. At autopsy there is no electric mark anywhere on the body, and the internal findings are non-specific. The defence argues that the absence of an electric mark rules out electrocution. What is the best explanation for the absence of a mark?

    1. ALow-voltage current leaves a mark only at exit
    2. BAn electric mark appears only after a day
    3. CNo mark means she died before the contact
    4. DWet skin has low resistance, so no mark may form

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15. Question 15 · Hard

    The body of a 30-year-old man is recovered from a temple tank in Kumbakonam about 18 hours after he was last seen. The autopsy surgeon weighs four findings: 1. The wrinkled, bleached skin of the palms and soles proves he was alive when he entered the water. 2. Diatoms in the femoral bone marrow matching the tank water support antemortem drowning. 3. Weeds firmly clutched in his hand in cadaveric spasm support antemortem drowning. 4. Voluminous, waterlogged lungs that overlap the heart and pit on pressure support drowning. Which statements are correct?

    1. A1, 2 and 3 only
    2. B2 and 3 only
    3. C1, 3 and 4 only
    4. D2, 3 and 4 only

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16. Question 16 · Medium

    A 25-year-old electrician in Surat touches a live 230 V alternating current wire with his right hand while standing barefoot on a wet floor. He collapses instantly and cannot be revived. What is the most likely mechanism of death?

    1. ABurn shock from extensive burns
    2. BVentricular fibrillation
    3. CRespiratory centre paralysis
    4. DMyoglobinuric acute kidney injury

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