Positional asphyxia
Encyclopedia
Positional asphyxia, also known as postural asphyxia, is a form of asphyxia
which occurs when someone's position prevents them from breathing adequately. A small but significant number of people die suddenly and without apparent reason during restraint by police
, prison
(corrections) officers and health care
staff. Positional asphyxia may be a factor in some of these deaths.
Risk factors which may increase the chance of death include obesity, prior cardiac or respiratory problems, and the use of illicit drugs such as cocaine. Almost all subjects who have died during restraint have engaged in extreme levels of physical resistance against the restraint for a prolonged period of time. Other issues in the way the subject is restrained can also increase the risk of death, for example kneeling or otherwise placing weight on the subject and particularly any type of restraint hold around the subject's neck. Research measuring the effect of restraint positions on lung function suggests that restraint which involves bending the restrained person or placing body weight on them, has more effect on their breathing than face down positioning alone.
(BMI) and/or large waist girth.
in the blood of the victim, which proved effective in their small scale study. This approach appears to be supported by another report of a single case of successful resuscitation.
which has not been studied in laboratory simulations. An alternative explanation of some deaths may be excited delirium
, but there is also a degree of controversy and disagreement regarding this.
and ex-Major League Baseball player John Marzano
both died due to positional asphyxia, the former following an epileptic seizure and the latter following a fall down a flight of stairs.
Asphyxia
Asphyxia or asphyxiation is a condition of severely deficient supply of oxygen to the body that arises from being unable to breathe normally. An example of asphyxia is choking. Asphyxia causes generalized hypoxia, which primarily affects the tissues and organs...
which occurs when someone's position prevents them from breathing adequately. A small but significant number of people die suddenly and without apparent reason during restraint by police
Police
The police is a personification of the state designated to put in practice the enforced law, protect property and reduce civil disorder in civilian matters. Their powers include the legitimized use of force...
, prison
Prison
A prison is a place in which people are physically confined and, usually, deprived of a range of personal freedoms. Imprisonment or incarceration is a legal penalty that may be imposed by the state for the commission of a crime...
(corrections) officers and health care
Health care
Health care is the diagnosis, treatment, and prevention of disease, illness, injury, and other physical and mental impairments in humans. Health care is delivered by practitioners in medicine, chiropractic, dentistry, nursing, pharmacy, allied health, and other care providers...
staff. Positional asphyxia may be a factor in some of these deaths.
- Positional asphyxia is a potential danger of some physical restraint techniques,
- People may die from positional asphyxia by simply getting themselves into a breathing-restricted position they cannot get out of, either through carelessness or as a consequence of another accidentAccidentAn accident or mishap is an unforeseen and unplanned event or circumstance, often with lack of intention or necessity. It implies a generally negative outcome which may have been avoided or prevented had circumstances leading up to the accident been recognized, and acted upon, prior to its...
.
Prone restraint
Research has suggested that restraining a person in a face down position is likely to cause greater restriction of breathing than restraining a person face up. Multiple cases have been associated with the hogtie or hobble prone restraint position. Many law enforcement and health personnel are now taught to avoid restraining people face down or to do so only for a very short period of time.Risk factors which may increase the chance of death include obesity, prior cardiac or respiratory problems, and the use of illicit drugs such as cocaine. Almost all subjects who have died during restraint have engaged in extreme levels of physical resistance against the restraint for a prolonged period of time. Other issues in the way the subject is restrained can also increase the risk of death, for example kneeling or otherwise placing weight on the subject and particularly any type of restraint hold around the subject's neck. Research measuring the effect of restraint positions on lung function suggests that restraint which involves bending the restrained person or placing body weight on them, has more effect on their breathing than face down positioning alone.
Other restraint positions
Positional asphyxia is not limited to restraint in a face down position. Restraining a person in a seated position may also reduce the ability to breathe, if the person is pushed forwards with the chest on or close to the knees. The risk will be higher in cases where the restrained person has a high body mass indexBody mass index
The body mass index , or Quetelet index, is a heuristic proxy for human body fat based on an individual's weight and height. BMI does not actually measure the percentage of body fat. It was invented between 1830 and 1850 by the Belgian polymath Adolphe Quetelet during the course of developing...
(BMI) and/or large waist girth.
Resuscitation
Resuscitation of persons who exhibit cardiac arrest following restraint has proven to be difficult. Even in cases where the subject was in the immediate care of paramedics, resuscitation has failed and the subject has died. One group of doctors has presented a method of resuscitation, correcting acidosisAcidosis
Acidosis is an increased acidity in the blood and other body tissue . If not further qualified, it usually refers to acidity of the blood plasma....
in the blood of the victim, which proved effective in their small scale study. This approach appears to be supported by another report of a single case of successful resuscitation.
Debate regarding positional asphyxia
There is a degree of controversy amongst researchers regarding the extent to which restraint positions restrict breathing. Some researchers report that when they conducted laboratory studies of the effects of restraint on breathing and oxygen levels, the effect was limited. Other researchers point out that deaths in real life situations occur after prolonged, violent resistanceExcited delirium
Excited delirium is a condition that manifests as a combination of delirium, psychomotor agitation, anxiety, hallucinations, speech disturbances, disorientation, violent and bizarre behavior, insensitivity to pain, elevated body temperature, and superhuman strength...
which has not been studied in laboratory simulations. An alternative explanation of some deaths may be excited delirium
Excited delirium
Excited delirium is a condition that manifests as a combination of delirium, psychomotor agitation, anxiety, hallucinations, speech disturbances, disorientation, violent and bizarre behavior, insensitivity to pain, elevated body temperature, and superhuman strength...
, but there is also a degree of controversy and disagreement regarding this.
Positional asphyxia due to accident or illness
Positional asphyxia may also occur as a result of accident or illness. Olympic track athlete Florence Griffith-JoynerFlorence Griffith-Joyner
Florence Griffith-Joyner , also known as Flo-Jo was an American track and field athlete. She is considered the "fastest woman of all time" based on the fact that she still holds the world record for both the 100 metres and 200 metres, both set in 1988 and never seriously challenged...
and ex-Major League Baseball player John Marzano
John Marzano
John Robert Marzano commonly referred to as Johnny Marz was an American catcher in Major League Baseball who played from 1987 to 1998 for the Boston Red Sox, Texas Rangers and Seattle Mariners, generally as a backup catcher...
both died due to positional asphyxia, the former following an epileptic seizure and the latter following a fall down a flight of stairs.
External links
- http://www.fbi.gov/publications/leb/1996/may966.txt
- http://www.cpsc.gov/businfo/frnotices/fr01/bedrail.html
- http://www.cdc.gov/niosh/face/in-house/full8723.html