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How To Do Bag-Valve-Mask (BVM) Ventilation


Dorothy Habrat

, DO, Department of Emergency Medicine, University of New Mexico School of Medicine

Last full review/revision Aug 2019| Content last modified Mar 2021
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Bag-valve-mask (BVM) ventilation is the standard method for rapidly providing rescue ventilation to patients with apnea or severe ventilatory failure.

In BVM ventilation, a self-inflating bag (resuscitator bag) is attached to a nonrebreathing valve and then to a face mask that conforms to the soft tissues of the face. The opposite end of the bag is attached to an oxygen source (100% oxygen) and usually a reservoir bag. The mask is manually held tightly against the face, and squeezing the bag ventilates the patient through the nose and mouth. Unless contraindicated, airway adjuncts such as nasopharyngeal and/or oropharyngeal airways are used during BVM ventilation to assist in creating a patent airway. Positive end expiratory pressure (PEEP) valves should be used if further assistance is needed for oxygenation without contraindications to its use.

Successful BVM ventilation requires technical competence and depends on 4 things:

  • A patent airway

  • An adequate mask seal

  • Proper ventilation technique

  • PEEP valve as needed to improve oxygenation

Establishing a patent airway for BVM ventilation requires

Rapid provision of successful ventilation and oxygenation is the goal.

Indications for BVM Ventilation

  • Emergency ventilation for apnea, respiratory failure, or impending respiratory arrest

  • Pre-ventilation and/or oxygenation or interim ventilation and/or oxygenation during efforts to achieve and maintain definitive artificial airways (eg, endotracheal intubation)

Contraindications to BVM Ventilation

Complications of BVM Ventilation

If bag-valve-mask ventilation is used for a prolonged period of time or if improperly performed, air may be introduced into the stomach. If this occurs and gastric distention is noted, a nasogastric tube should be inserted to evacuate the accumulated air in the stomach.

Equipment for BVM Ventilation

  • Gloves, mask, gown, and eye protection (ie, universal precautions)

  • Oropharygeal airways, nasopharygeal airways, lubricating ointment

  • Bag-valve apparatus

  • PEEP valve

  • Variably sized ventilation face masks

  • Oxygen source (100% oxygen, 15 L/minute)

  • Nasogastric tube

  • Suctioning apparatus and Yankauer catheter; Magill forceps (if needed to remove easily accessible foreign bodies and patient has no gag reflex) to clear the pharynx as needed

  • Pulse oximeter

  • Capnography equipment

Additional Considerations for BVM Ventilation

  • Two-person bag-valve-mask (BVM) ventilation is used whenever possible. Bag-valve-mask ventilation can be done with one person or two, but two-person BVM ventilation is easier and more effective because a tight seal must be achieved and this usually requires two hands on the mask.

  • Unless contraindicated, a pharyngeal airway adjunct is used when performing BVM ventilation. An oropharyngeal airway is used unless the patient has an intact gag reflex; in such cases, a nasopharyngeal airway (nasal trumpet) is used. Bilateral nasopharyngeal airways and an oropharyngeal airway are used if necessary for ventilation.

  • Among the many factors that can make achieving an air-tight seal difficult are facial deformity (traumatic or natural), a thick beard, obesity, poor dentition, trismus, and cervical pathology. In such situations, BVM is attempted, but if it is unsuccessful, a supraglottic airway is placed (unless contraindicated).

  • A positive end expiratory pressure (PEEP) valve may be used during BVM to improve oxygenation. PEEP can increase alveolar recruitment and thus oxygenation if oxygenation is compromised even with 100% oxygen due to atelectasis. PEEP has also been shown to prevent lung injury. However, PEEP should be used cautiously in patients who are hypotensive or pre-load dependent because it reduces venous return.

Positioning for BVM Ventilation

The sniffing position—only in the absence of cervical spine injury

  • Position the patient supine on the stretcher.

  • Align the upper airway for optimal air passage by placing the patient into a proper sniffing position. Proper sniffing position aligns the external auditory canal with the sternal notch. To achieve the sniffing position, folded towels or other materials may need to be placed under the head, neck, or shoulders, so that the neck is flexed on the body and the head is extended on the neck. In obese patients, many folded towels or a commercial ramp device may be needed to sufficiently elevate the shoulders and neck. In children, padding is usually needed behind the shoulders to accommodate the enlarged occiput.

Head and neck positioning to open the airway: Sniffing position

A: The head is flat on the stretcher; the airway is constricted. B: The ear and sternal notch are aligned, with the face parallel to the ceiling (in the sniffing position), opening the airway. Adapted from Levitan RM, Kinkle WC: The airway Cam Pocket Guide to Intubation, ed. 2. Wayne (PA), Airway Cam Technologies, 2007.

Head and neck positioning to open the airway

If there is concern for cervical spine injury:

  • Position the patient supine or at a slight incline on the stretcher.

  • Position yourself at the head of the stretcher.

  • Avoid moving the neck and, if possible, use only the jaw-thrust maneuver or chin lift without head tilt to manually facilitate opening of the upper airway.

Relevant Anatomy for BVM Ventilation

  • Aligning the external auditory canal with the sternal notch may help open the upper airway to maximize air exchange and establishes the best position to view the airway if endotracheal intubation becomes necessary.

  • The degree of head elevation that best aligns the ear and sternal notch varies (eg, none in children with large occiputs, a large degree in obese patients).

Step-by-Step Description of Procedure

Two-person mask technique

One-person mask technique

Bag ventilation and oxygenation

  • For each breath, steadily and smoothly squeeze the bag, to deliver a tidal volume of 6 to 7 mL/kg (or about 500 mL for an average size adult) over 1 second, and then release the bag to allow it to reinflate. If using a 1000-mL volume bag, squeeze only halfway to obtain the correct tidal volume.

  • In cardiac arrest cases, do not exceed 8 to 10 breaths per minute (ie, one complete breath every 6 to 7.5 seconds).

  • Observe for proper chest rise during ventilations; in practice, you can use a tidal volume just large enough to cause the chest to rise.

  • Monitor the patient, checking breath sounds and, if possible, end-tidal carbon dioxide and pulse oximeter. (Pulse oximetry may not be useful during cardiac arrest due to poor peripheral perfusion.) Assess if adequate ventilation is continuous and sustainable or is requiring too much physical effort. If available, use waveform capnography, an excellent indicator of mask seal and proper ventilation.

  • If oxygenation is inadequate despite proper form and use of 100% oxygen, attach a positive end expiratory pressure (PEEP) valve to recruit more alveoli for gas exchange. Set the PEEP valve initially at 5 and increase as needed to improve oxygen saturation. However, avoid PEEP in hypotensive patients.

  • If ventilation or oxygenation is still not adequate, prepare for other airway maneuvers such as a supraglottic airway or endotracheal intubation.

Aftercare for Bag-Valve-Mask Ventilation

  • Continue bag-valve-mask (BVM) ventilation until either a definitive artificial airway (eg, endotracheal tube) is achieved or spontaneous ventilation is adequate (eg, following naloxone administration for an opioid overdose).

  • If a patient becomes more conscious or a gag reflex returns while doing BVM ventilation with an oropharyngeal airway in place, remove the oropharyngeal airway and provide continued treatment as appropriate. A nasopharyngeal airway may be better tolerated.

  • If endotracheal intubation is necessary, ventilate using maximum FiO2 through a non-rebreather mask for 3 to 5 minutes before inserting the tube if feasible; if this is not feasible because intubation must proceed immediately, pre-oxygenate the patient by giving 5 to 8 vital capacity breaths using a PEEP valve.

Warnings and Common Errors for BVM Ventilation

  • Do not place your hands or the mask on the patient’s eyes. Doing so may damage the eyes or cause a vagal reaction.

Tips and Tricks for BVM Ventilation

  • Neither excessive force nor rapid insufflation should be used to ventilate; doing so increases gastric distention, compromising ventilation.

  • A nasogastric tube is inserted to help decompress the stomach when possible.

References for BVM Ventilation

  • Soleimanpour M, Rahmani F, Ala A, et al: Comparison of four techniques on facility of two-hand bag-valve-mask (BVM) ventilation: E-C, thenar eminence, thenar eminence (dominant hand)-E-C (non-dominant hand) and thenar eminence (non-dominant hand) - E-C (dominant hand). J Cardiovasc Thorac Res 8(4):147-151, 2016. doi:10.15171/jcvtr.2016.30.

  • Otten D, Liao MM, Wolken R, et al: Comparison of bag-valve-mask hand-sealing techniques in a simulated model. Ann Emerg Med 63(1):6-12.e3, 2014. doi:10.1016/j.annemergmed.2013.07.014.

More Information about BVM Ventilation

  • Jarvis JL, Gonzales J, Johns D, et al: Implementation of a clinical bundle to reduce out-of-hospital peri-intubation hypoxia. Ann Ermerg Med 72(3):272 - 279.e1, 2018.

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