Bag-Valve-Mask Ventilation - Amplified

Quick Reference

Ventilation Goals

• Tidal volume: 500-600mL (6-8mL/kg ideal body weight)
• Rate: 10-12 breaths/min in adults (1 breath every 5-6 seconds)
• Target: SpO2 >94%, visible chest rise with each breath

The main risks are hyperventilation (causes gastric distension, reduces venous return, worsens outcomes in cardiac arrest) and aspiration (unconscious patients have no airway protection).

Equipment Overview

Prep

Check bag integrity (squeeze test)

Occlude the patient outlet and squeeze the bag. It should hold pressure and not deflate. A leaking bag won't deliver adequate volumes. Also check that the valve moves freely and the bag recoils quickly when released.

Attach reservoir bag

The reservoir bag (the tail on the end) collects oxygen between breaths. Without it, you're diluting with room air and delivering only 40-60% O2. With it attached and O2 flowing, you can deliver close to 100% FiO2.

Connect to O2 at 15L/min

Connect the oxygen tubing to the inlet port. Set flow to 15L/min - this is the maximum on most flowmeters and ensures the reservoir stays inflated. Watch the reservoir bag inflate before you start ventilating.

Select correct mask size

The mask should create a seal from the bridge of the nose to the cleft of the chin, covering both nose and mouth. It should NOT overlap the eyes (pressure injury, poor seal) or sit on the chin (air leak).

Execute

One-Person Technique

C-E grip: Make a "C" with your thumb and index finger over the mask, pressing it onto the face. Your other three fingers form an "E" under the mandible, lifting the jaw upward. This simultaneously seals the mask AND opens the airway.

Maintain head tilt: Keep the head tilted back (unless C-spine concern) to keep the airway open. Your "E" fingers should be on bone (mandible), not soft tissue under the chin - pressing on soft tissue pushes the tongue back and obstructs the airway.

Squeeze bag: Use your other hand to squeeze the bag, delivering 500-600mL (about half to two-thirds of the bag). Watch for chest rise - this is your indicator of adequate ventilation.

Two-Person Technique

This is the preferred method when two rescuers are available because it provides a much better mask seal.

Person 1: Uses both hands to hold the mask with a two-handed jaw thrust grip. Thumbs press down on the mask, fingers lift the jaw from both sides. Focus entirely on maintaining the seal and head position.

Person 2: Squeezes the bag with both hands, controlling rate and volume. Can watch for chest rise and adjust technique.

Ventilation

Rate: 10-12 breaths per minute. In cardiac arrest, this means one breath every 6 seconds (or every 30 compressions in 30:2 CPR). Counting helps - "squeeze-two-three-four-five-six" then squeeze again.

Watch for chest rise: This is your feedback that ventilation is working. If no chest rise:

• Reposition the head (more tilt)
• Improve mask seal
• Check for obstruction
• Try jaw thrust

Avoid hyperventilation: More is not better. Excessive rate or volume causes gastric inflation, increases intrathoracic pressure (reduces venous return), and worsens outcomes. Stick to the numbers.

Finish

Monitor SpO2

Attach a pulse oximeter if not already on. Target SpO2 >94% (or 88-92% in known CO2 retainers). If SpO2 isn't improving despite good technique, consider: airway obstruction, equipment failure, or need for advanced airway.

Prepare for advanced airway if needed

BVM is a bridge, not a destination. If the patient needs ongoing ventilation, prepare for:

• Supraglottic airway (LMA, i-gel) - easier, doesn't require laryngoscopy
• Endotracheal intubation - definitive airway, requires skilled operator

Troubleshooting

Poor mask seal

• Beard: apply water-based lubricant or cover with transparent dressing
• Facial trauma: may need surgical airway
• Edentulous patient: leave dentures in if possible, or pack cheeks

Gastric distension

• Caused by excessive pressure or too-fast ventilation
• Increases aspiration risk, splints diaphragm
• Management: insert NG/OG tube, reduce ventilation pressure

No chest rise

1. Reposition airway (head tilt, jaw thrust)
2. Check mask seal
3. Suction if secretions
4. Consider airway adjunct (OPA/NPA)
5. Consider foreign body

When to escalate

• Unable to maintain SpO2 >94%
• Prolonged resuscitation expected
• Need for airway protection (blood, vomit)
• Transport of unconscious patient