We pick up the ventilation bag and start manually bagging our patients without a second thought. Something so simple yet there is a science behind it. If not used correctly, we as providers could cause additional harm. Are we hyperventilating, over-ventilating, hypoventilating, giving a 300cc VT or an 800cc VT? Ineffective manual ventilation can result in cardiopulmonary instability. Low volume and low pressure are key. These are some of the things we should be thinking about.
Recognizing the need to manually ventilate a patient.
- Hypercapnic respiratory failure
- Altered mental status
- Total upper airway obstruction
Let’s talk about the self-inflating ventilation bag.
*** Use caution when holding the self-inflating ventilation bag on the patients’ face without bagging. There is no free-flowing oxygen. More of this topic HERE ***
Do you know how to bag a patient?
- Self-inflating adult ventilation bag can deliver up to 1900ml VT (each package states the ml VT). It is easy to hyperventilate and over-ventilate patients as there is limited ability to gauge tidal volumes delivered. Compressing the ventilation bag too much can cause high delivered airway pressures and tidal volumes. When over-ventilating we do not allow for exhalation. This is sure to cause volutrauma and or barotrauma. To avoid this, ideally bag with two people. One provider to squeeze the bag over one second until the chest rises while keeping the pressures low. The other provider holds a good seal of the mask on the face. *This will also help to reduce hand fatigue. You can switch off between the two providers. It’s a team sport.
- You can ideally use an adult mask with a pediatric ventilation bag to prevent over bagging. The pediatric ventilation bag can usually deliver up to 1L of volume. Using a pediatric ventilation bag will also lower the ventilation pressures.
- If the patient has spontaneous respirations, try to squeeze the ventilation bag along with the patient as much as possible to achieve best ventilation. Bagging against the patient will cause possible coughing and gastro-distention. It can also result in poor ventilation and accelerate hypoxia.
- When paying attention to the bag dynamics you may be able to detect and feel the patient’s respiratory effort and lung compliance when an advanced airway is in place.
Let’s talk about the use of a pediatric ventilation bag with adult mask to manually ventilate adults
Both adult and pediatric ventilation bags exceed the maximum lung protection volumes, however the pediatric ventilation bag provides safer and more consistent lung protective ventilation volumes and pressures. High pressures and volumes are contributed with alveolar damage. Studies have suggested that manually ventilating adults with a pediatric ventilation bag is possible.
What’s a good seal?
- Proper positioning is vital
- Make sure the mask is covering both the nose and the mouth. How many times have you seen the nose smashed or the bottom lip hanging out?
- Head tilt, chin lift maneuver or jaw thrust in sniffing position.
- There are different ways to hold the mask. You can hold the mask on the patients’ face using your two thumbs (V-E technique) or one handed (C-E technique).
- Make sure with the remaining fingers you’re pulling up on the posterior mandible.
Unable to obtain a proper seal?
- Try an oropharyngeal and/or nasopharyngeal airway
- Reposition the head making sure sniffing position is obtained.
How do you know if ventilation is effective?
- Adequate chest rise
- Breath sounds over lungs
- Waveform capnography
Effective ventilation is crucial. So are you bagging your patient correctly?
- Make sure your BMV has a reservoir and at least 15LPM of oxygen flow.
- Do not use 2 hands to bag! Consider using a pediatric BVM for adults.
- Get a good seal! Use the C-E technique when you can only use one hand to hold the seal. Use the V-E technique when you can use 2 hands to hold the seal.
Dafilou B, Schwester D, Ruhl N, Marques-Baptista A. It’s In The Bag: Tidal Volumes in Adult and Pediatric Bag Valve Masks. West J Emerg Med. 2020 Apr 27;21(3):722-726. doi: 10.5811/westjem.2020.3.45788. PMID: 32421525; PMCID: PMC7234703.
Whitten, Christine. “Difference in Manual Ventilation: Self-Inflating Ventilation Bag vs. a Free Flow Inflating Bag.” The Airway Jedi, 23 Sept. 2019, airwayjedi.com/2017/03/26/manual-ventilation-self-infalting-vs-free-flow-bag/.