Chapter 9: Asphyxia

Vocabulary flashcards about asphyxia

Asphyxia

A broad term encompassing conditions that interfere with oxygen uptake or utilization.

Brain's Oxygen Consumption

Brain constitutes 2% of body weight but uses 20% of available oxygen.

Brain Cell Regeneration

Brain cells do not regenerate after oxygen deprivation.

Time to Unconsciousness (Brain)

Sudden lack of blood to the brain causes unconsciousness within 5-10 seconds.

Hanging

Compression of the neck without blocked airway example.

Smothering

Obstruction of the airway example.

Carbon Monoxide Poisoning

Exclusion of oxygen example; chemical interference with oxygen uptake.

Hanging Cause of Death

Arrest of arterial blood flow or obstruction of venous return to the brain.

Semi-Suspension Hanging Signs

Purple, dusky, cyanotic, swollen face, sometimes bulging eyes.

Total Suspension Hanging Signs

Pale face, absent subconjunctival and cutaneous petechiae.

Petechiae Cause

Increased venous pressure above the noose.

Petechiae Location

Conjunctivae, skin of eyelids, forehead, upper cheeks.

Hanging Knot Position

Can be behind the ears (nape of neck) or below the chin.

Pressure to Occlude Carotid Arteries/Jugular Veins

Five to six pounds of pressure per square inch.

Pressure to Block Airway

Thirty-two pounds of pressure required.

Suicide Hanging Noose Mark

Loop climbs upward toward the neck.

Homicide Hanging Noose Mark

Mark is usually horizontal or downward.

Tongue Protrusion in Hanging

Upward pressure on neck organs by the noose, causing elevation of the tongue.

Strangulation Types

Homicidal, suicidal, or accidental.

Manual Strangulation Hallmarks

Fingertip bruises and fingernail marks on the neck.

Hyoid Bone

Horseshoe-shaped bone at the level of the lower jaw, at the base of the tongue.

Petechiae in Strangulation

Supportive evidence of death; vascular phenomenon.

Carotid Sleeper Hold

Constricts the carotid arteries, reduces blood flow to the brain.

Smothering

Blockage of the nose and mouth, usually homicidal.

Positional Asphyxia

Position interferes with ability to breathe.