Asphyxia | Medical Science Optional Notes for UPSC PDF Download

Types of Hanging

Hanging vs Strangulation

Hanging-Cause of deat

• Asphyxia: The constricting force of a ligature induces compressive narrowing of the laryngeal and tracheal lumina, leading to asphyxia.
• Venous congestion: The ligature blocks the jugular veins, causing a halt in cerebral circulation; this occurs when the ligature is composed of broad and soft material.
• Combined asphyxia and venous congestion: This represents the most common cause.
• Cerebral anemia: This occurs when the ligature is made of a thin cord.
• Reflex vagal inhibition leading to sudden cardiac arrest.
• Fracture/dislocation of cervical vertebrae: This is observed in cases of judicial hanging.

Cafe Coronary
Death of men in cafes and restaurant

Photograph of the victim along with ligature (if present) is recommended.

Internal Examination

Examination of anterior neck structures, including the tongue, larynx, trachea with the thyroid gland, attached strap muscles (including sternocleidomastoid muscles), and submandibular glands, is conducted prior to their removal. The use of a modified Y-shaped incision is recommended for optimal exposure of the neck structures.

• The tongue undergoes inspection and is incised from tip to base to assess for hemorrhage.
• The presence of hemorrhages in the submandibular glands and strap muscles is observed.
• The thyroid gland is extracted and sectioned.
• Any hemorrhage or fractures in the muscles surrounding the cricoid, laminae of the thyroid cartilage, and superior horns are documented.
• The hyoid bone is palpated, and any hemorrhages adjacent to the hyoid or thyrohyoid ligament are recorded. The hyoid is dissected away, with caution regarding the variable length of the lesser cornua, which may be inadvertently cut.
• Longitudinal sections through the larynx may be performed to detect intracartilaginous hemorrhages in suspected hanging cases.
• The posterior dissection of the esophagus and larynx-trachea is conducted to observe any submucosal hemorrhage, petechiae, mucosal injuries, and signs of aspiration.

Ligature marks/furrows

• Location: Typically situated above the hyoid bone.
• Dimensions/Configuration: Determined by the nature of the material employed.
• Orientation: It follows an oblique, backward, non-continuous, upward trajectory toward the point of suspension.
• The mark is noncontinuous due to a gap at the nape of the neck, with hair intervening between the ligature material and the skin beneath.

When the knot makes contact with the skin, it typically forms an inverted 'V' shape, resulting from the extension of the ligature material downward on both sides from the knot positioned above.

Skin at the site: Initially exhibits depression or grooving, appearing pale, but later adopts a yellowish-brown hue, becoming dry, hard, and parchment-like. Small abrasions emerge at the edges, corresponding to the thickness and edges of the rope, and these friction-induced abrasions are termed rope burns.

The ligature pattern may be replicated in the furrow. Postmortem blisters might develop on the skin adjacent to the furrow, which has been subjected to compression.

An abraded region below the furrow may indicate upward slippage of the ligature, typically observed in cases of complete suspension. Distension of neck veins above the furrow may also be apparent.

Antemortem hanging-Triad of characteristics based on Liagture

The diagnosis of antemortem hanging can be established by examining the ligature mark on the neck when the following triad of characteristics is evident: 
i. Presence of streaks or bands of reddened or pink tissue 
ii. Imprint of the ligature pattern discernible in the furrow 
iii. Sloping or upward angle directed towards the point of suspension. 

Types of Drowning

Post mortem signs of Drowning

Asphyxia-Repeats

Hanging

1. Define 'partial hanging' Describe typical ligature marks, seen in cases of ante-mortem hanging. How would you differentiate between ante-mortem hanging and post-mortem suspension (2002)?
2. How can you differentiate between hanging and strangulation? Discuss in detail (2006).
3. Describe how you will proceed to examine the "scene of crime in a case of hanging". Describe the differentiating features between hanging and strangulation postmortem examination. (2009) Describe various possible injuries and cause of death in case of successful hanging. (2016)

Drowning

1. What is the medico-legal importance of "Diatom" (2001)?
2. Define 'dry drowning' Describe postmortem findings in a case of drowning in fresh water (2005).
3. A dead body of a woman aged about 30 years was found in the river water. Describe how the autopsy surgeon will ascertain on post-mortem examination that the death was due to drowning. (2014)