As law enforcement officers, part of your job is to subdue and restrain violent people in order to protect yourself, others, and even the subject being restrained. Unfortunately, the techniques you use to control and restrain the subject may interfere with that individual’s ability to breathe. This can result in an in-custody death from a phenomenon called positional asphyxia.

Despite the name, positional asphyxia is not just about the position of the subject’s body. There are precipitating factors that make positional asphyxia deadly. These factors include intoxication due to alcohol, drug use, obesity, psychiatric illnesses, and physical injury. Positional asphyxia may even be caused simply by the subject getting into a breathing-restricted position they cannot get out of, either through their own carelessness or as a consequence of an accident or illness. Some people have suffered seizures that trapped them in positions where their breathing was restricted and death has resulted.

Positional asphyxia is a potential danger of some common physical restraint techniques. That’s why it is necessary for law enforcement officers to know and understand that preexisting risk factors combined with the body position of the subject when subdued or while in transport can increase the risk of in-custody death.

Risk Factors

There are certain risk factors that may render some subjects more susceptible to positional asphyxia following a struggle with law enforcement officers. This is especially true if the subject is restrained and placed in a face-down or prone position.

Common risk factors of death from positional asphyxia include but are not limited to excessive alcohol intoxication, drug use, obesity, and medical conditions such as an enlarged heart. An individual with an enlarged heart can have a greater susceptibility to a cardiac arrhythmia (irregular heartbeat) when under conditions of stress and when there are low levels of oxygen in the blood stream.

The following is a closer look at some factors and circumstances that can make an individual more susceptible to death from positional asphyxia.

Violent Struggle—People who have engaged in a difficult and aggressive struggle may be more susceptible to respiratory muscle fatigue and failure.

Excited Delirium—Subjects who are under the influence of cocaine or methamphetamine while in restraints may experience a condition known as excited delirium. This disorder results in disorientation, hallucinations, and impaired thinking. Excited delirium may raise the individual’s susceptibility to a sudden increase in heart rate, which can rise to a critical level and result in cardiac arrest.

Alcohol Intoxication and Drugs—Alcohol is a significant risk factor in positional asphyxia because it lowers the respiratory drive. Individuals who have been drinking heavily are among the most likely to die in custody from medical events.

Body Position—Death due to a head-down position with hyper flexion of the neck is a rare event. It is however a critical condition arising out of particular body positions that can lead to mechanical obstruction of respiration. Studies have 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 of death by positional asphyxia have been associated with the hog tied or prone restraint position. The risk of positional asphyxia is further compounded when a suspect with predisposing medical conditions becomes involved in a violent struggle with an officer. This is especially true when the physical restraint includes the use of behind-the-back handcuffing combined with placing the individual in a stomach down 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.

Other aspects of how the subject is restrained can also increase the risk of positional asphyxia death. Placing a knee or weight on the subject and particularly any type of restraint hold around the subject’s neck can be problematic. Research measuring the effect of restraint positions on lung function suggests that restraint that involves bending the restrained person or placing body weight on them has a greater effect on breathing than face-down positioning alone.

When restraining a person in a seated position, the risk will be higher in cases where the restrained person has a high body mass index (BMI). A large waist girth may also reduce the ability to breathe, if the person is pushed forward.

Mitigating the Risk

In order to ensure the safety and to minimize the risk of positional asphyxia resulting in an in-custody death, law enforcement officers should learn to recognize contributing factors and conditions that contribute to positional asphyxia.

1. When feasible, officers should avoid the use of prone restraint techniques.

2. Learn and follow department guidelines and policy for situations involving physical restraint of individuals.

3. Once the suspect is handcuffed, get them off the face-down position.

4. Inquire about the recent use of drugs or if the subject has a cardiac condition or any respiratory conditions or diseases.

5. Have someone monitor the subject.

6. Obtain medical evaluation and treatment if needed.

7. Pass on any information about drug or alcohol use and medical conditions to the personnel at the detention facility where the subject will be incarcerated.

In-custody death is one of the great tragedies in law enforcement and one of the most common causes is positional asphyxia. To reduce the risk of positional asphyxia, the use of maximal face-down position restraint techniques should be avoided. If it is necessary to position a person face-down under restraint, then the subject must be closely and continuously monitored. By doing so and following procedures discussed in this article, the potential for in-custody deaths from positional asphyxia can be lessened. 

Lawrence Heiskell, MD, FACEP, FAAFP is an emergency physician and a veteran reserve police officer with the Palm Springs (CA) Police Department. He is the founder and medical director of the International School of Tactical Medicine.