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Steve Haywood
Former Respiratory Therapist working to de-mystify the ventilator through hands-on workshops and online education. Additional interests include HFNC in CHF and COPD, Medical Education, and Tupperware.

Caleb Harrell MD
Emergency Medicine by day, Critical Care by night. Trained at The University of Tennessee and The University of Florida. Hobbies include hiking, biking, liking, and pyrex portables.
The Pre-brief
Can a Bag-Valve-Mask (BVM) be used to pre-oxygenate without squeezing the bag? Will oxygen come through the mask to the patient? Will room air be entrained through the exhalation port lowering the FiO2 in your admixture? With some experimentation, we will definitely answer these questions.
The Debrief
You can use a BVM for pre-oxygenation without squeezing the bag with the following caveats.
- The BVM must be attached to high flow oxygen (>15LPM) and have a reservoir attached.
- The patient must have adequate respiratory effort. If not, you should be squeezing the bag.
- You must hold a tight seal against the patient’s face. This tight seal is necessary to open the valve from the bag to the mask.
- You must use a PEEP valve. Depending on the brand of BVM, the patient may be able to entrain room air through the exhalation valve. A PEEP valve assures no air will come in through the exhalation port.
PEER Reviewed by
Dr. Matt Siuba
PEER Reviewed by
Dr. Haney Mallemat
We use adult flow inflating bags in our shop. Great for preoxygenation (I’d say better than an NRB) with the added CPAP benefit.
Hello Ivan, are those similar or identical to anesthesia bags?