Bag-Valve-Mask (BVM) Ventilation

BVM ventilation is time-critical once oxygenation falls. Match the rate to whether an advanced airway is in place, and stop squeezing at visible chest rise. Ratios and rates follow the 2025 AHA Guidelines for CPR and ECC (Parts 6–9).

Bag-valve-mask (BVM) ventilation pushes air into the lungs with a self-inflating bag and a face mask. You reach for it when the patient cannot breathe well enough on their own. You also use it in cardiac arrest, until an advanced airway is in place.

How It Works

• Seal: the mask has to lock onto the face. Leak and high resistance are the usual reasons mask ventilation fails.
• Airway: open it first. Use a head tilt–chin lift, or a jaw thrust if trauma is suspected. Add an oral or nasopharyngeal airway when the patient needs one.
• Breath: squeeze over about 1 second, and stop when the chest rises. Extra volume does not reach the lungs. It goes to the stomach.
• Oxygen: run high flow with the reservoir attached, about 15 L/min. For pediatric CPR the AHA recommends 100% oxygen (2025 AHA Guidelines for CPR and ECC, Part 6, COR 2a).

Where It Fits

Where does BVM sit in the plan? The Difficult Airway Society (DAS) 2015 algorithm puts mask ventilation at Plan C. You reach it after a failed intubation (Plan A) and a failed second-generation supraglottic airway (Plan B). When the mask cannot work at all, you need paralysis to avoid critical hypoxia. A cannot-intubate, cannot-oxygenate (CICO) call sends you to front-of-neck access (Plan D). Plan C is written for anaesthesia. In US EMS, the same step is rescue ventilation under local protocol. In adult cardiac arrest, bag-mask ventilation or an advanced airway may be considered. The call depends on the situation and the professional's skill set (2025 AHA Guidelines for CPR and ECC, Part 9, COR 2b). For out-of-hospital pediatric arrest, bag-mask ventilation is reasonable rather than an advanced airway (2025 AHA Guidelines for CPR and ECC, Part 8, COR 2a).

Indications

• Apnea, or breathing too inadequate to oxygenate or ventilate, with a pulse present
• Cardiac arrest, until an advanced airway is in place
• Oxygenation between induction and laryngoscopy in critically ill adults (PREVENT trial)
• Rescue ventilation after failed intubation or supraglottic airway placement (DAS Plan C)

Absolute Contraindications

None when the patient needs ventilation. Do not hold BVM while you wait for a different device.

Relative Contraindications & Cautions

• A mask seal that cannot be made: fix the seal or change the route
• Beard, facial trauma or burns, missing teeth, or obesity. Expect a poor seal. Add a second rescuer and an airway adjunct early.
• Upper-airway obstruction, such as a foreign body. Clear the airway first. Squeezing the bag will not move it.
• High airway pressure from poor lung compliance or high resistance. Air goes to the stomach. Lower the volume and slow each breath.
• Suspected spinal injury: keep the head in line and use a jaw thrust, not head tilt

Consider an Alternative

Once BVM cannot hold oxygenation, move to an advanced airway. Pick intubation when a tube is feasible. Or use a supraglottic airway (Plan B). If CICO is declared, see cricothyrotomy.

Abort / Stop Criteria

• No chest rise after one reposition and re-seal. Change the technique, not the force.
• Three failed attempts with one technique: move to the next plan, with one more try by a more skilled clinician

Team Roles During the Procedure

• Airway holder: seals the mask and holds the jaw up with two hands in the two-person technique.
• Bag operator: squeezes each breath over about 1 second to visible chest rise.
• Monitor and counter: watches EtCO₂, SpO₂ and the abdomen, and keeps the rate.
• Equipment support: has suction, oral and nasopharyngeal airways and the rescue device ready.

Ventilation Difficulty

The 2022 ASA guideline defines difficult mask ventilation by three problems. An inadequate seal. Excessive gas leak. Excessive resistance.

Physiologic Risk

• Hypoxemia: in critically ill adults, severe hypoxemia (SpO₂ below 80%) hit 10.9% of patients given BVM between induction and laryngoscopy. With no ventilation at all, the rate was 22.8%.
• Gastric inflation: when airway patency fails, air goes down the esophagus. That raises aspiration risk.

Site / Device Check

Confirm the bag and mask are the right sizes, the reservoir is attached, oxygen is running, suction is ready and capnography is connected.

Equipment

Sizing

Patient Positioning & Preparation

Use the sniffing position. More pharyngeal room means better mask ventilation, per DAS 2015. Trauma or a suspected spinal injury gets a jaw thrust. Anyone else gets a head tilt–chin lift.

Phase 1: Prepare

1. Assign roles: one person seals and holds the jaw, one squeezes the bag, one monitors and counts. Call for help early.
2. Check the set: suction on, bag assembled, reservoir attached, oxygen running at high flow, capnography connected.
3. Position the patient: flat, head in a sniffing position, mask size chosen before you start.

Phase 2: Perform

4. Open the airway: head tilt–chin lift. Use a jaw thrust when trauma or spinal injury is suspected.
5. Insert an airway adjunct: an oral or nasopharyngeal airway if the patient tolerates it and the seal needs it.
6. Seal the mask: one rescuer seals with one hand and squeezes the bag with the other, or uses both hands on the mask when the seal is hard. Confirm the seal before the first breath.
7. Squeeze over about 1 second: give each breath just enough to make the chest rise. Release the bag so the chest can deflate.

8. Set the rate: 30 : 2 with compressions and no advanced airway; 1 breath every 6 s (10/min) once an advanced airway is placed, with compressions continuing.
9. Watch the abdomen and the pressure: if the stomach swells or the bag turns hard to squeeze, re-seal, reposition and reduce the volume.
10. Read the EtCO₂ waveform: a sustained waveform shows that air is reaching the lungs (see Confirmation & Monitoring).

Phase 3: Confirm & Secure

11. Confirm lung inflation: visible chest rise with every breath, plus the SpO₂ and EtCO₂ trend.
12. Hand off to the advanced airway: once a tube or supraglottic airway is in, ventilate at the advanced rate without pausing compressions. Confirm again after every move.
13. Document: time, adjuncts, bag and mask sizes, rate, EtCO₂, SpO₂ and any problems (see Handoff & Documentation).

Alternative Technique: Two-Person Mask Seal

Two hands on the mask, one rescuer keeping the airway open. A second rescuer squeezes the bag. Both check for visible chest rise. The E-C grip works like this: thumbs and index fingers seal the mask while the other fingers lift the jaw into it. With no advanced airway in place, two rescuers beat one. It suits severe airway obstruction, poor lung compliance or a hard seal.

Adjunct: PEEP Valve

A PEEP valve on the bag holds some pressure in the lungs between breaths. When hypoxemia lingers despite a good seal, that can help oxygenation. Use it per local protocol. The catch: higher pressure raises the risk of gastric inflation. Keep an eye on the belly and the bag pressure.

Primary Confirmation

How do you know the air got in? Chest rise on every breath, and a sustained waveform EtCO₂ once capnography is connected. The 2022 ASA guideline advises capnography to confirm adequate ventilation when possible.

Secondary Confirmation

• SpO₂ steady or rising, not falling
• Abdomen flat or only slightly rising
• Bag squeezes without high resistance

Ongoing Monitoring

• EtCO₂ continuously while ventilating, when available
• Seal and chest rise after every reposition or move
• Breaths counted each minute against the rate in Key Numbers

Pediatrics

• Bag size: at least 450–500 mL for term newborns and infants; 1,000 mL for larger children and adolescents.
• Ratio before an advanced airway: 30 : 2 with one rescuer, 15 : 2 with two (2025 AHA Guidelines for CPR and ECC, Part 6, COR 2a).
• Breath length: give each breath over 1 second. No rise? Reposition the head, seal tightly and retry.
• Cricoid pressure: do not use it routinely during bag-mask ventilation (2025 AHA Guidelines for CPR and ECC, Part 8, COR 3: No Benefit). If you do use it, stop as soon as it interferes with ventilation (COR 3: Harm).
• After cardiac arrest: it may be reasonable to target normoxemia and a PaCO₂ suited to the child's condition. The aim is to limit exposure to both hypercapnia and hypocapnia (2025 AHA Guidelines for CPR and ECC, Part 8, COR 2b).

Once an advanced airway is in, or when a child has a pulse but breathes inadequately, the rate is 20–30 breaths/min (1 breath every 2–3 s) (2025 AHA Guidelines for CPR and ECC, Part 6, COR 2a; Part 8, COR 2b). Observational work linked at least 30 breaths/min in children under 1 year with ROSC, which is why the rate moves with age and clinical state.

For sizing and dosing, read equipment sizing, pediatric airway, Broselow and weight-based dosing.

Trauma and C-Spine

• In children, use a jaw thrust if trauma, especially cervical spine injury, is suspected. If it is inadequate and the situation is life-threatening, revert to head tilt–chin lift.

Pregnancy

• Left uterine displacement: when the fundal height is at or above the umbilicus, displace the uterus manually to the left with compressions (2025 AHA Guidelines for CPR and ECC, Part 10, COR 1, LOE C-LD). Lying supine lowers cardiac output in pregnancy.
• Aspiration risk: airway management comes early, per protocol. Keep suction ready (2025 AHA Guidelines for CPR and ECC, Part 10, COR 1, LOE C-LD).
• Resuscitative delivery (formerly perimortem cesarean): indicated when the fundal height is at or above the umbilicus and ROSC is not achieved with standard resuscitation (2025 AHA Guidelines for CPR and ECC, Part 10, COR 1, LOE B-NR). Start preparing at recognition. The goal is to complete delivery by 5 minutes.

Toxicology: Opioid Overdose

• Respiratory arrest with a pulse: ventilate at 10/min with BVM (2025 AHA Guidelines for CPR and ECC, Part 7, COR 2a). Give an opioid antagonist (2025 AHA Guidelines for CPR and ECC, Part 10, COR 1, LOE B-NR). Adult: ventilate first, then naloxone 0.2–2 mg IV/IO/IM or 2–4 mg IN, repeat every 2–3 min, titrate to breathing (2025 AHA Guidelines for CPR and ECC, Part 10, Table 4). Differs from FDA label: the label starts at 0.4 mg. Pediatric: 0.1 mg/kg IV/IO (max 2 mg; IN max 4 mg per NASEMSO), repeat every 2–3 min (2025 AHA Guidelines for CPR and ECC, Part 10, Table 4). Differs from FDA label: the label starts at 0.01 mg/kg.
• Opioid-related cardiac arrest: an opioid antagonist may be reasonable if high-quality CPR is not interrupted (2025 AHA Guidelines for CPR and ECC, Part 10, COR 2b; LOE B-NR adults, C-EO children). The evidence is very low. Never delay compressions or breaths for it.

Physiologically Difficult Patients

• In critically ill adults, BVM between induction and laryngoscopy reduced severe hypoxemia. Operator-reported aspiration did not rise significantly (2.5% vs 4.0%, P = 0.41).
• Before induction, preoxygenate everyone. DAS 2015 recommends it for all patients.

Immediate Aftercare

• Once a tube or supraglottic airway is confirmed, ventilate at the advanced rate and check EtCO₂.
• After adult ROSC: 100% oxygen until SpO₂ or PaO₂ can be reliably measured, then titrate FiO₂ to SpO₂ 90–98%. If the patient remains comatose, keep PaCO₂ within 35–45 mm Hg (2025 AHA Guidelines for CPR and ECC, Part 11, COR 1 and 2a).
• Keep the bag on the device until the airway is confirmed and secured.

Ongoing Maintenance

• Keep the HEPA filter in the circuit where one is used.
• Recheck the seal and the rate at every handoff and move.

Transport Considerations

• Reassess the seal, chest rise and EtCO₂ after every move or turn.
• Use a metronome or spoken count to hold the rate on long transports.

Pearls

• Chest rise is the endpoint: stop squeezing when the chest rises. Extra volume goes to the stomach.
• Two people beat one: the two-person technique works better when no advanced airway is in place.
• Bag before laryngoscopy: gentle BVM between induction and laryngoscopy cut severe hypoxemia in critically ill adults.
• Escalate on time: three attempts per technique, then the next plan.

Common Pitfalls

• Squeezing hard and fast: hard, fast squeezes push air into the stomach. Use about 1-second breaths to chest rise, at a set rate.
• One-person grip on a hard seal: add a second person for a two-hand grip.
• Routine cricoid pressure during bagging: not recommended in adults (2025 AHA Guidelines for CPR and ECC, Part 7, COR 3: No Benefit) or children (2025 AHA Guidelines for CPR and ECC, Part 8, COR 3: No Benefit).
• Trusting the bag over the waveform: confirm with chest rise and EtCO₂.
• Trying past three attempts: escalate to the next plan.