Signs of strangulation include bruises, marks on the neck, bleeding in the throat, and fracture of the hyoid bone, a U-shaped bone at the base of the tongue.

Asphyxiation, or death due to a lack of oxygen, can have many causes, including strangulation or compression of the neck, suffocation, drowning, choking, and hanging.

In the case of strangulation, the autopsy would typically reveal injury to the neck caused by manual compression, something tied around the neck, or hard blows to the neck, which can damage the larynx and lead to suffocation. Hallmarks of strangulation include bruises, fingernail or ligature marks on the neck, bleeding in the throat area, and a fracture of the hyoid bone, a U-shaped bone located at the base of the tongue.

Evidence of suffocation include   petechial hemorrhages - red splotches - in the eyes, face, lungs, and neck area.

   Physical evidence suggestive of suffocation    would  include the presence of petechial hemorrhages in the eyes, face, lungs, and neck area. Petechiae are tiny purple or red spots on the skin that are caused by small areas of bleeding under the skin.

Signs of asphyxiation due to drowning include foam in the airways (which forms due to the mixing of mucus and water as the victim struggles to breath), an enlarged heart, the presence of algae and other water-borne substances in the stomach or airways, and sometimes, changes in the blood caused by water that is taken in during drowning.

Source:
Zachary Lysek, Northampton County Coroner, Northampton County, PA.

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