Carotid compression
Other names | Sleeper hold |
---|---|
Health risk | High |
Legal risk | High |
Carotid compression involves reducing arterial blood flow to the brain by external compression of one or both of the common carotid arteries to induce sensations of lightheadedness or cause loss of consciousness.[1] This can be performed using several specific techniques such as the sleeper hold. Many of the considerations of carotid compression overlap with breath control, although carotid compression typically does not include restriction of airflow and has several additional unique risks.
Background
The common carotid arteries are large arteries which provide most of the blood flow to the brain. When blood flow to the brain is restricted:
- Consciousness is lost within seconds
- Permanent brain damage occurs within minutes
- Death is all but certain after 10 minutes
When carotid compression is applied, the subject will typically experience presyncopal symptoms for a few seconds prior to losing consciousness.[1] Presyncopal symptoms include:
- Lightheadedness
- Feelings of warmth
- Vision changes (loss of color vision, vision going dark or closing in)
When consciousness is lost, the subject will have no ability to control their body and may exhibit specific involuntary signs, such as:
- Eyes rolling back into the head
- Loss of muscle tone
- Abnormal posturing
- Abnormal or obstructed breathing
When consciousness returns, subjects can exhibit brief seizure-like activity prior to regaining control of their body and awareness of their surroundings. Initially, subjects are often quite disoriented, feeling as if they woke up from a dream with no memory of the events immediately preceding loss of consciousness. Full memory typically recovers several seconds later.
Appeal
Methods
- The "sleeper hold", which uses a triangular choking technique which occludes both carotid arteries from lateral compression. When properly executed, this hold does not apply pressure to the trachea (windpipe) and airflow is not restricted.
- Direct compression using the fingers or hands
Risks and risk mitigation
The major risks of carotid compression include:
- Stroke
- Injury to airway or vascular structures
- Bodily injury from falling
- Airway obstruction or aspiration
- Cardiac arrest (from the carotid sinus reflex)
It is critically important to recognize when unconsciousness occurs and immediately restore normal blood flow to the brain. If restriction of flow is prolonged after consciousness is lost, the unconscious person will not have any further added experience, while the risk of permanent injury greatly increases.
Carotid compression should never be practiced when carotid plaques could be present due to the high risk of plaque dislodgement and embolic stroke. More than 50% of older adults (>60 years old) have some degree of carotid plaque formation. Middle-aged adults (40-60 years old) can develop carotid plaques, with higher prevalence among those with risk factors (hypertension, high cholesterol, smoking, diabetes, cardiovascular disease).