Bag-Mask Ventilation (BMV) is a manual resuscitation technique using a self-inflating bag and a face mask to deliver positive pressure breaths to a patient who is not breathing adequately. This is a common and immediate method for resuscitation in emergencies. Achieving a tight, airtight seal between the mask and the patient’s face is fundamental. Without this seal, air leaks out, failing to inflate the lungs and making effective ventilation impossible.
Optimizing Airway Position Before Ventilation
A proper mask seal alone is insufficient; the airway must be open for successful ventilation. In an unconscious patient, the tongue falling back against the pharynx is the most common cause of blockage. Rescuers must correctly position the patient’s head to align the oral, pharyngeal, and tracheal axes.
For an adult patient without a suspected neck injury, the head-tilt/chin-lift maneuver opens the airway. This involves tilting the head backward with one hand on the forehead while lifting the chin upward with the fingers of the other hand. For infants or children, a less aggressive “sniffing position” involving only slight head extension is preferred.
If a spinal injury is suspected, the head-tilt maneuver must be avoided. The jaw thrust maneuver is performed instead, involving placing fingers under the angles of the jaw and lifting it forward. This action displaces the jaw bone, pulling the tongue off the back of the throat to maintain an open airway.
The Standard Hand Grip for Sealing the Mask
Once the airway is positioned, the rescuer applies the single-person “E-C clamp” or “C-E technique.” One hand secures the mask and maintains the open airway while the other hand squeezes the bag. The thumb and index finger of the non-dominant hand form a “C” shape over the top of the mask.
The “C” applies gentle but firm downward pressure onto the mask’s body, pressing it snugly onto the patient’s face. The remaining three fingers—the middle, ring, and little finger—form an “E” shape. These fingers are placed under the bony part of the patient’s jaw, or mandible.
The “E” fingers actively lift the jaw upward toward the mask. This lifting motion simultaneously helps maintain the airway and pulls the patient’s face up into the mask to complete the seal. The goal is to lift the face toward the mask, rather than pushing the mask down, which can inadvertently obstruct the airway.
When One Hand Is Not Enough
The single-rescuer “E-C clamp” technique may not be sufficient to create an adequate seal, resulting in air leakage. Factors that make sealing difficult include facial hair, obesity, being toothless, or anatomical variations. When an effective seal cannot be maintained with one hand, the “Two-Person Technique” is preferred.
This advanced method requires a second rescuer to squeeze the bag while the first rescuer uses both hands to secure the mask. The primary rescuer forms two C-E clamps, one on each side of the mask. The thumbs and index fingers of both hands form opposing “C” shapes around the mask connector, applying uniform pressure.
The remaining fingers of both hands curl under the patient’s jaw, providing a stronger, more symmetrical upward lift. This two-handed grip is more effective at overcoming facial irregularities and generating the pressure needed for a successful seal. Selecting a mask of the correct size—covering from the bridge of the nose to the cleft of the chin without compressing the eyes—is a prerequisite for achieving a reliable seal.