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.
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.