Bag-Valve-Mask Ventilation

Updated: Apr 05, 2022
  • Author: Nichole Bosson, MD; Chief Editor: Zab Mosenifar, MD, FACP, FCCP  more...
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Bag-valve-mask (BVM) ventilation [1] is an essential emergency skill. This basic airway management technique allows for oxygenation and ventilation of patients until a more definitive airway can be established and in cases where endotracheal intubation or other definitive control of the airway is not possible. For the emergency medical technician, basic BVM ventilation is most often the only option for airway management. [2, 3, 4]

In the pediatric population, BVM may be the best option for prehospital airway support. [5, 6]  BVM ventilation is also appropriate for elective ventilation in the operating room (OR) when intubation is not required, [7]  but it is now often replaced in this setting by the laryngeal mask airway. [8]

BVM ventilation requires a good seal and a patent airway. Practice with this important skill increases the clinician’s ability to provide effective ventilation. Adjuncts such as oral and nasal airways can aid with ventilation by relieving physiologic obstruction and by opening up the hypopharynx. Certain factors predict difficult BVM ventilation. These include the presence of facial hair, lack of teeth, a body mass index (BMI) greater than 26, age older than 55 years, and a history of snoring. [9]

Masks come in many sizes, including newborn, infant, child, and adult (small, medium, and large). Choosing the appropriate size helps create a good seal and thereby facilitates effective ventilation.

Bags for BVM ventilation also come in different types. Newer bags are equipped with a pressure valve. Some bags have one-way expiratory valves to prevent the entry of room air; these allow for delivery of more than 90% oxygen to ventilated and spontaneously breathing patients. Bags lacking this feature deliver a high concentration of oxygen during positive-pressure ventilation (PPV) but deliver only 30% oxygen during spontaneous breaths. [8]



Indications for BVM ventilation include respiratory failure (failure of ventilation, oxygenation, or both) and failed intubation.



BVM ventilation is absolutely contraindicated in the presence of complete upper-airway obstruction. It is relatively contraindicated after paralysis and induction (because of the increased risk of aspiration).