Strangling is compression of the neck that may lead to unconsciousness or death by causing an increasingly hypoxic state in the brain. Fatal strangling typically occurs in cases of violence, accidents, and is one of two main ways that hanging may cause death (alongside breaking the victim's neck).
Strangling does not have to be fatal; limited or interrupted strangling is practised in erotic asphyxia, in the choking game, and is an important technique in many combat sports and self-defence systems. Strangling can be divided into three general types according to the mechanism used:
Strangling involves one or several mechanisms that interfere with the normal flow of oxygen into the brain:
Depending on the particular method of strangulation, one or several of these typically occur in combination; vascular obstruction is usually the main mechanism. Complete obstruction of blood flow to the brain is associated with irreversible neurological damage and death, but during strangulation there is still unimpeded blood flow in the vertebral arteries. Estimates have been made that significant occlusion of the carotid arteries and jugular veins occurs with a pressure of around 3.4 N/cm2 (4.9 psi), while the trachea demands six times more at approximately 22 N/cm2 (32 psi).
As in all cases of strangulation, the rapidity of death can be affected by the susceptibility to carotid sinus stimulation.Carotid sinus reflex death is sometimes considered a mechanism of death in cases of strangulation, but it remains highly disputed. The reported time from application to unconsciousness varies from 7–14 seconds if effectively applied to one minute in other cases, with death occurring minutes after unconsciousness.