Pocket masks are most traditionally used during single rescuer CPR, where the use of bag-valve-masks may be unwieldy. While these devices are less commonly used in the EMS setting due to the almost universal partner system, there are some situations where you may encounter one.
The most portable of the mechanical ventilation device which provides protection to the rescuer from direct mouth-to-mouth contact is the pocket mask. This section will review the use of and limitations of the pocket mask.
Use of a Pocket Mask
To provide assisted ventilations through a pocket mask, take a position on either side of a supine patient.
- Place the mask over the nose and mouth of the patient, verifying a tight seal (EC technique).
- Ensure the "barrier device tip" is in place, this is a one-way valve that prevents backflow.
- Manually open the airway using either a jaw thrust or combination head tilt and chin lift.
- Deliver a breath over approximately one second, watching for equal chest rise and fall.
Pocket mask ventilation has the disadvantage of limiting the time available for other interventions and being strenuous on the rescuer, often quickly causing fatigue.
The air provided by the pocket mask will have a low oxygen percentage (14%-16% vs. the 21% in normal air) since it has already passed through the rescuer's lungs. This is offset by the presence of oxygen ports on some pocket masks. The use of pocket masks is typically limited to first-aid situations in the community. Lifeguards, teachers, and home health aides are most likely to encounter pocket masks.
Normal expired air is composed of approximately 14% oxygen. Supplemental oxygen through the oxygen outlet—flow rate set at approximately 6-8 Lpm—will deliver upwards of 50%-60% oxygen.