Medical effects

A hanging may cause one or more of the following medical conditions:

   * Close the carotid arteries causing cerebral ischemia
   * Close the jugular veins
   * Induce carotid reflex, which reduces heartbeat when the pressure in the carotid arteries is high, causing cardiac arrest
   * Break the neck (cervical fracture) causing traumatic spinal cord injury
   * Close the airway
   * Decapitation



Where death has been caused by blocking the veins, the face will typically have become engorged and cyanotic (turned blue through lack of oxygen). There will be the classic sign of strangulation—petechiae—little blood marks on the face and in the eyes from burst blood capillaries. The tongue may protrude. The person dies quickly, while others indicate a slow and agonising death by strangulation.

When cerebral circulation is severely compromised by any mechanism, arterial or venous, death occurs over four or more minutes from cerebral hypoxia, although the heart may continue to beat for some period after the brain can no longer be resuscitated. The time of death in such cases is a matter of convention. In judicial hangings, death is pronounced at cardiac arrest, which may occur at times from several minutes up to 15 minutes or longer after hanging. During suspension, once the prisoner has lapsed into unconsciousness, rippling movements of the body and limbs may occur for some time which are usually attributed to nervous and muscular reflexes. In Britain, it was normal to leave the body suspended for an hour to ensure death.

After death, the body typically shows marks of suspension: bruising and rope marks on the neck. Forensic experts may often be able to tell if hanging is suicide or homicide, as each leaves a distinctive ligature mark. One of the hints they use is the hyoid bone. If broken, it often means the person has been murdered by manual choking. Also, there have been cases of autoerotic asphyxiation leading to death.