Basic airway management can save your patient! Bag-valve-mask ventilation is an essential patient care skill, but many learners struggle to achieve a good mask seal. Without oxygen, the human brain suffers permanent damage in as few as 3 minutes. Your ability to quickly recognize respiratory distress, open an airway, and ventilate can make all the difference between life and death for your patient.
Health care providers often equate emergency airway management with intubation. However, airway management is much more than that. One case of mine in particular stands out as a good example.
Case
I arrived in the ICU to assist the intensivist after an intubation gone wrong. The airway had been lost and the intensivist was prepping to perform an emergency cricothyrotomy in a morbidly obese patient who was difficult to intubate. Oxygen saturation was a critical 50% and dropping. The respiratory therapist was frantically smashing the mask down on the patient’s face, forcing the chin down over the chest, trying unsuccessfully to ventilate with bag-valve-mask.
Taking over ventilation attempts, I tilted the patient’s head back to open the airway, inserted an oral airway, and then reapplied the mask with a good seal. Immediately the chest began to rise with ventilation. Oxygen saturation quickly rose as well. Crisis averted, we avoided surgical cricothyrotomy, got the video-laryngoscope, and intubated the patient in a controlled manner.
The patient still needed intubation. However, what saved that patient from disaster was basic airway management skills:
- opening an airway,
- inserting an oral or a nasal airway,
- ventilating with bag-valve mask
- all of which require teamwork and communication
This guide moves step by step through mask selection, seal formation, ventilation technique, troubleshooting, and key takeaways so you can build a reliable approach to bag-valve-mask ventilation. You will also find my original 30 minute Basic Airway management video posted free on YouTube here.
Author’s Note: This post was originally published in December 2012 and has been completely revamped and updated for accuracy and comprehensiveness.
1. Choose the Correct Mask Size
Stand behind the patient’s head and select the correct mask size. The mask should extend from the bridge of the nose to the crease of the chin, with both lips inside. A mask that is too large or too small will not seal well and can make mask ventilation difficult.
During ventilation, gas follows the path of least resistance. A well-fitted mask creates an airtight seal, directs gas into the lungs, and produces chest rise. A poor fit causes leaks and makes lung inflation harder. As a guide, use size 3 for large children, size 2 for toddlers, and size 1 for infants. Most adult women need a small to medium mask, most men a medium, and tall or heavier men may need a large.
2. Form and Maintain a Good Mask Seal
Extend the head to open the airway. If cervical spine injury is suspected, keep the neck neutral. The basic technique is the same for adults and children, with pediatric differences noted separately.
Masks are roughly triangular. Place the apex at the top of the nasal bridge where it meets the forehead and press firmly. A common mistake is placing the apex in the middle of the nose, which prevents a proper seal. Keep the mask clear of the eyes.
With your free index and middle fingers, pull the cheeks forward on both sides so the mask edges catch the tissue. Make sure the lower lip is inside the mask.
Pull the Face into the Mask
Do not press the mask straight onto the face. Instead, use your fingers to pull the face into the mask. The thumb provides counterpressure to form the seal, while the upward pull extends the head and helps open the airway.
Use the “C-E” Hand Position
The third, fourth and fifth fingers of your left hand are already on the jawbone and pulling it upward. Now move your left thumb into position at the top of the mask to maintain your seal against the bridge of the nose. Your left index finger will now fall naturally into place below the connection to the ventilation bag. This finger placement allows the index finger to control the angle and the pressure of the mask against the face on a breath-to-breath basis. Because the head will tend to move during ventilation and other treatments, such as CPR, this ability to continuously optimize mask seal as the head moves is important.
Let’s look at that final finger position again. Thumb and forefinger press the mask against the face and form a “C” shape. The remaining fingers grip the boney mandible and pull upward, forming an “E”.
Protect The Eyes
The mask can open the eyelids and expose the eyes to corneal abrasion, especially in children, whose eyes are proportionally larger. If the patient is unconscious, consider taping the eyes closed.
3. Ventilate While Preserving a Good Mask Seal
Left vs. Right Hand
Most providers hold the mask seal with the left hand and squeeze the bag with the right, allowing the usually dominant right hand to handle the greater physical effort. In some situations, however, patient position or other factors make it necessary to switch hands. With practice, either hand position can be used effectively.
Ventilation Technique
Maintain your mask seal and jaw lift with the left hand while you take your right hand off the mask. Your right hand will now squeeze the bag and ventilate the patient. The chest should visibly rise with each breath.
Manage Leaks During Ventilation
If you have a good seal at the top of the mask, follow these steps to close any side leaks:
- shift the mask angle with your index finger to press the mask more firmly against the opposite side of the face,
- rotate your ventilation bag to allow its weight to help you create a seal,
- have an assistant help seal the mask by pushing cheek tissue against the mask to block any leaks.
Use Minimal Force Needed To Inflate The Lungs
Use only the minimum force needed to inflate the lungs. Slow, steady breaths work better than quick puffs because they are more likely to expand the lungs and less likely to inflate the stomach. Think blowing, not panting.
Stomach inflation elevates the diaphragm, limiting lung expansion and increasing the risk of vomiting and aspiration. If it makes ventilation difficult, decompress the stomach with a flexible suction catheter or an oro/nasogastric tube. When the tube enters a distended stomach, you can often see the abdomen decompress.
Assess Ventilation Effectiveness
Assess each breath by watching for visible chest rise, noticing the resistance felt when squeezing the bag, checking for fogging in the mask, and confirming breath sounds or exhaled CO2 when available. If the chest does not rise, first assume the ventilation is inadequate and reassess the mask seal, airway position, and possible obstruction before attributing the problem to lung pathology.
Changes in lung compliance can also affect how easy the bag is to squeeze. Compliance refers to the lungs’ ability to stretch and expand; poor compliance means the lungs are stiffer. Conditions such as pneumonia, bronchospasm, and pneumothorax reduce compliance and make ventilation more difficult.
Always watch the chest rise as you ventilate. The amount of rise helps estimate the tidal volume being delivered. Keep the airway open to prevent air from entering the stomach.
Stomach distention can severely impair ventilation. When the diaphragm cannot descend, air cannot enter the lungs easily. If distention occurs, pass a soft suction or orogastric tube to decompress the stomach; ventilation often improves markedly afterward
If you’re unsure, have a helper listen for breath sounds on both sides of the chest.
Compensate For Dead Space
Consider dead space when ventilating a patient to ensure adequate alveolar ventilation. Dead space is the portion of tidal volume that does not participate in gas exchange. It includes anatomic, physiologic, and equipment dead space.
Anatomic dead space is air in ventilated airways that does not take part in gas exchange, including the pharynx, trachea, bronchi, and bronchioles.
Physiologic dead space consists of ventilated alveoli that are not adequately perfused. It can vary moment to moment with changes in cardiac output and pulmonary blood flow.
Equipment dead space is added by airway devices used during ventilation, such as the circuit, bag, and mask itself.
In adults, anatomic dead space is about one-third of normal tidal volume, or 2 mL/kg; in young children, it is about 3 mL/kg. Anything in the airflow path—such as an adapter or the portion of an endotracheal tube outside the mouth—adds dead space. If manually delivered breaths do not account for this extra volume, alveolar ventilation may be inadequate. The smaller the tidal volume, the greater the relative effect of equipment dead space.
The next figure shows the end of an anesthesia breathing circuit. In this example, the circuit, bacterial/humidification filter, and elbow adapter add at least 50 mL of equipment dead space. Although 50 mL seems small, alveolar ventilation will be poor if the delivered tidal volume is near or below that amount.
For more on how dead-space effects ventilation see: Equipment Dead Space Affects Ventilation
Allow Your Hand To Relax Between Breaths
Allow your patient to exhale between breaths. Relax the ventilating hand slightly for the few seconds it takes for the bag to refill. Little or no air will escape around the mask with a good mask seal. You can tolerate a small leak as long as you can ventilate the patient.
The hand holding the mask will tire quickly if kept constantly tensed. Fatigue then interferes with ability to ventilate. Maintain the mask seal using the least amount of tension in your hands as possible. Don’t allow your hand to assume a “claw” shape as it goes into tetany. Gripping the mask too tightly can cause your hand to cramp. Instead, rest the palm of your hand against the cheek. Use your shoulder and arm strength to help maintain the seal, not just your finger grip.
Ask for help in making the seal or squeezing the bag if needed.
Continually Re-Assess Ventilation
Reassess throughout ventilation. If you notice poor chest rise, an unusually easy bag squeeze, increased resistance, stomach inflation, or absent breath sounds, return to the fundamentals: improve the seal, reposition the airway, suction if needed, and ask for help before assuming the patient’s underlying condition is the main cause.
4. Troubleshoot Difficult Mask Ventilation
Reposition the Mask
Always start by repositioning the mask and obtaining a good seal.
Place An Oral or Nasal Airway
If ventilation is challenging, place an oral or nasal airway. Occasionally patients will need both.
Use Additional Airway-Opening Maneuvers
Add a more pronounced jaw thrust with positive pressure breaths. Hook your fingers under the mandible and pull the lower jaw forward. This maneuver mimics the action of an oral airway without inserting one into a patient too awake to tolerate it. Suction the secretions, if any, to prevent aspiration.
Reposition the Mask Or Bag Weight
There is often a leak on the side of the mask opposite the hand holding the mask. Simply tilting the mask toward the leak can help. When possible, rotating the weight of the bag-valve-mask apparatus to sit over the leak can also help seal the leak.
Reposition The Head and Neck As Needed
You may sometimes need to reposition the head to optimally open the airway for ventilation. Start by placing the external ear canals level with the chest. Position can make a big difference in ventilating a child depending on age because of the differing anatomy. Placing a folded sheet or towel under the head of a patient older than 2 years aligns the pharyngeal and laryngeal axes. A child younger than 2 years has a relatively large occiput. Placing the towel under the shoulders in this age group is often more effective than under the head.
Ask for Help to Seal the Mask
Obtaining a good mask seal in an edentulous or heavier patient can be especially challenging. Ask one of your assistants to help you create the seal by holding the mask tight against the patient’s face at the leak points.
Use Two-Person Mask Ventilation
If difficulty persists, use both hands to seal the mask while a helper squeezes the bag. A two-handed seal better advances the mandible and lifts obstructing tissue off the larynx. This is especially helpful in heavier patients and children with enlarged adenoids or tonsils.
Adjust your fingers to improve the seal. Place your thumbs on top of the mask and index fingers below, bunching the cheeks under the mask. With the remaining fingers along the jawline beneath the angle of the mandible, lift the jaw firmly upward.
Grip only the bone. Pressure on the soft tissue under the jaw can worsen obstruction.
Good communication is essential when a helper squeezes the bag because you can no longer feel bag compliance. Have your helper report any obstruction or leak immediately. Watch for chest rise and mask condensation, and have someone listen for breath sounds. This is a team effort. Look for chest movement and fogging of the mask, listen for breath sounds, and of you have it monitor end-tidal-CO2.
5. Key Takeaways on Mask Ventilation
- Mask ventilation is crucial, and achieving a good mask seal is key for effective ventilation.
- Select the correct mask size, ensuring it fits from the nose bridge to the chin, and securely positions on the face.
- Use proper finger placement: thumb and index form a ‘C’ while the other three form an ‘E’ for optimal sealing.
- Regularly reassess ventilation effectiveness and adjust techniques, including repositioning the mask and using appropriate airflow maneuvers.
- In challenging situations, consider two-person ventilation for better support and communication during the process.
Note: Illustrations from Basic Airway Management: A Step-by-Step Guide
Free Youtube training video on Airway Management
Links to other articles on mask ventilation:
- Assisting Ventilation With Bag-Valve-Mask
- Exhaling During Manual Ventilation Is As Important As Inhaling
- Mask Ventilation: Avoiding Hand Fatigue
- Difference In Manual Ventilation: Self Inflating Ventilation Bag vs. Free Flow Inflating Bag
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