• To provide ventilatory support to apnoeic patients or those with insufficient respiratory effort to enhance oxygenation. Examples include:
    • Cardio-respiratory arrest,
    • Respiratory arrest, or
    • Who have ineffective respiratory effort and are able to tolerate it.
Patient Factors & Considerations

SMART BVM's and / or AMBU BVMs may both be available - this guidance is as generic as possible

  • Facial hair can affect seal, utilise KY jelly on areas were mask is to be seated.
  • Be mindful of ventilation rate and pressure:
    • Excessive ventilation pressure usually results in gastric distention and may compromise patency.
    • Ventilating large volumes at high pressure with a mask will result in gastric distension and risk of regurgitation.
    • If an i-gel®/ETT is in-situ, excess pressures in the thorax can be generated, impeding blood flow and can precipitate lung injury.
    • Gentle ventilation at lower pressure will mitigate this. Some BVM’s may have built-in valves to prevent this.
    • Tidal volume is usually approx 7mL/kg – this is hard to judge with BVM. Aim for chest rise but avoid excessive rise.
  • Inability to ventilate indicates possible airway obstruction
  • Patients less than 10kg should not spontaneously breathe through the BVM, due to possible suffocation.
  • AMBU Bag BVM - The ‘pop off’ valve (if fitted) should remain in the open position when used in paediatric, infant and newborn patients. In some instances where higher airway pressures might be required such as upper airway obstruction, consideration could be given to close the pop-off valve, if there is an inability to ventilate. This should be a cautious decision.
  • SMART-Bag BVM - In cardiac arrest, the flow restrictor should be engaged to avoid over-ventilation. This can be disengaged if the patient requires higher tidal volumes. The timing light should also be activated as a guide to prompt each adult inflation at 6 secs (~ after every 10th compression)
  • Cricoid pressure is de-emphasised.
  • Asthmatics and COPD patients require assisted ventilations at a lower ventilation rate of 4-6 breaths/min to allow better exhalation.
  • Newborn patients should be ventilated with air initially; premature newborn should be ventilated with blended air – BVM at 1 L/min as per Newborn Life Support CPG.
  • Do not ventilate against effective spontaneous efforts - attach SpO2 monitoring. Discontinue oxygenation through SMART BVM if saturations fail to rise >88% despite
  • All relevant infection control methods to be utilised.
  • Position the patient as necessary
  • Prepare equipment required:
    • Bacterial filter MUST be attached always
    • End-tidal CO2 (etCO2) must be attached regardless of adjunct for any use of BVM
    • BVM
    • Oxygen
    • Suction
  • Ensure the BVM is functional; seal the mask connecter with your hand and depress the bag to ensure there are no leaks.

Note: In cardiac arrest, compressions MUST NOT be interrupted for more than 2-3 secs to facilitate ventilation. Work as a team.

  1. Adjust oxygen flow rate to 10-15 litres per minute and allow the reservoir bag to fill completely before and between ventilations.
  2. Place patient in the most optimal position.
  3. Place the apex of the mask over the bridge of the patient’s nose, and then seal the mask over the patient’s chin. Open airway with jaw thrust and chin lift.
  4. Utilise the 'anaesthetist grip' to ensure a firm seal of the mask on the patient’s face. 
  5. Reposition as required.
  6. Ventilate the patient as necessary; avoid hyperventilation and/or hyperinflation.
  7. In asynchronous CPR, the inflation MUST occur on the decompression phase (~after every 10th compression)

  1. Place patient in supine position.
  2. Continuously ensure the patient’s airway is patent, use suction if required, apply essential airway management and progress to advanced airway techniques if required.
  3. Attach BVM oxygen tubing to fir-tree port on O2 cylinder and turn regulator knob to ensure the reservoir bag inflates fully.
  4. Create an effective seal between the BVM and the face.
  5. Use an inverted hand at the end of the bag to avoid excess volume and pressure
  6. SMART BVM - The flow limiter is on the neck of the BVM, it should be engaged to limit pressure and volume in cardiac arrest
  7. Gently compress the bag to ventilate the patient. These can be timed with spontaneous breaths if necessary.
  8. Gauge the effort required to ventilate through the feel of the recoil bag to achieve minimal rise and fall of the chest. Excess pressure and volume is detrimental to the patient.
  9. The following ventilation rates are a guide for normal respiration values. DO NOT EXCEED.
  10. Do NOT provide asynchronous ventilation in paediatrics
Newborn 40 - 60 breaths per minute
< 1 year 30 - 40 breaths per minute
1 - 2 years 25 - 35 breaths per minute
2 - 5 years 25 - 30 breaths per minute
6 - 12 years 20 - 25 breaths per minute
> 12 years 15 - 20 breaths per minute
Adult 10 - 12 breaths per minute
  • If patient is not breathing at an effective rate, assisted ventilations are to be performed.
  • BVM resuscitator kit volumes:
Neonate 240 mL
Paediatric 500 mL
Adult 1600 mL

CPG 111 C Grip

"Anaesthetist Grip"


SMart BVM pair

Adult and combined Paediatric / Infant SMART BVM



Successful ventilation of a patient can be confirmed by factors such as:

  • Rise and fall of chest
  • Auscultation of lung bases and apexes, with air movement throughout
  • Rise in oxygen saturation (SpO2)
  • Reduction of cyanosis
  • Waveform capnography

If bag is tight, consider and address:

  • Poor patient positioining
  • Asthmatic hyperinflation
  • Tension pneumothorax
  • Airway obstruction
Additional Information
  • Impeded blood flow in cardiac arrest
  • Abdominal distension and regurgitation
  • Aspiration
  • Barotrauma and lung injury
  • Timing asynchronous inflation perfectly with decompression phases of CPR

Bag Mask Ventilation. (2014). Expert in My Pocket. http://expertinmypocket.com.au/bag-mask-ventilation/ 

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