A pocket mask, or pocket face mask or CPR mask, is a device used to safely deliver rescue breaths

Artificial respiration

Artificial respiration is the act of assisting or stimulating respiration, a metabolic process referring to the overall exchange of gases in the body by pulmonary ventilation, external respiration, and internal respiration...

 during a cardiac arrest

Cardiac arrest

Cardiac arrest, is the cessation of normal circulation of the blood due to failure of the heart to contract effectively...

 or respiratory arrest

Respiratory arrest

Respiratory arrest is the cessation of breathing. It is a medical emergency and it usually is related to or coincides with a cardiac arrest. Causes include opiate overdose, head injury, anaesthesia, tetanus, or drowning...

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Design

The pocket mask is a small device that can be carried on one's person. Air is administered to the patient when the emergency responder exhales through a one-way filter valve

Check valve

A check valve, clack valve, non-return valve or one-way valve is a mechanical device, a valve, which normally allows fluid to flow through it in only one direction....

. Modern pocket masks have either a built in one-way valve or an attachable, disposable filter to protect

Body substance isolation

Body substance isolation is a practice of isolating all body substances of individuals undergoing medical treatment, particularly emergency medical treatment of those who might be infected with illnesses such as HIV, or hepatitis so as to reduce as much as possible the chances of transmitting...

 the emergency responder from the patient's potentially infectious bodily substances, such as vomit or blood

Blood

Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

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Many masks also have a built-in oxygen intake tube, allowing for administration of 50-60% oxygen. Without being hooked up to an external line, exhaled air from the provider can still provide sufficient oxygen to live, up to 16%. Earth's atmosphere

Atmosphere

An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...

 consists of approximately 21% oxygen.

Usage

While a pocket mask is not as efficient as a bag valve mask

Bag valve mask

A bag valve mask is a hand-held device used to provide positive pressure ventilation to a patient who is not breathing or who is breathing inadequately. The device is a normal part of a resuscitation kit for trained professionals, such as ambulance crew...

, it does have its advantages when only one rescuer is available. As suggested by its name, the pocket mask benefits from a somewhat easier portability when compared to the bag valve mask. Also, in contrast to the bag valve mask, which requires two hands to operate (one to form a seal and the other to squeeze the bag), the pocket mask allows for both of the rescuer's hands to be on the patients head. This hand placement provides a superior seal on the patient's face, and allows the responder to perform a jaw thrust on patients suspected of a spinal injury

Spinal cord injury

A spinal cord injury refers to any injury to the spinal cord that is caused by trauma instead of disease. Depending on where the spinal cord and nerve roots are damaged, the symptoms can vary widely, from pain to paralysis to incontinence...

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