A few days ago I discussed how the resuscitator, BVM, aka “the ambu” could provide extremely high volumes, up to 1600cc if you get every last cc of O2 out of there, and therefore cause harm to your patient. A new buddy of mine via instagram, Matt, sent me a link to this article discussing this study where the authors wanted to know if our neighborhood EMS crews could ventilate patients appropriately using the smaller bags (450-500cc’s) like those used in pediatric patients. After all, that’s the what we are striving for with lung protective ventilation nowadays in the ICU, right? Why not get a head start on this in the field? That was also a secondary endpoint for the study. They also wanted to compare the volumes that patients would receive with a variety of different airway instruments. 

The authors went to their neighborhood EMS and fire stations and put the crews to the test. One thing to consider of course is that they’re going to perform their absolute best because they’re being watched. You’d do this, too, and so would I. Ultimately, they found that using the Ambu Spur II pediatric BVM, you can get a median tidal volume ranging from 570 to 664ml using an oropharyngeal airway, subglottilc airway and an endotracheal tube. That actually surprised me because I figured they would get less! Utilizing the Adult Ambu SPUR II BVM they got median volumes from 796 to 994.5ml utilizing the same three airway devices. That’s a lot of volume. 

This study surprised me on a number of levels where I did not expect to be surprised. First, the pediatric bags provided more volume than I expected. I expected a max of 500cc.  Second, these EMS personnel must’ve gotten some good seals on those dummies to get those volumes into them. They must’ve also been pumped that they were involved in a study and squeezed the crud out of those bags. Lastly, this makes me consider how I roll because sometimes the adult sized BVM is large, obstructive, and could be challenging to hold for someone with smaller hands than myself. I’ve had to bag patients in some tight spots (don’t ask) and having a pediatric bag would’ve definitely helped out the situation. 

I’m fortunate in that I usually have a second set of hands with me when I’m working on an airway but in the OR world, I’m sure there is an anesthetist or two out there who wouldn’t mind having a smaller device to handle. I know this study was performed on dummies but I can see one of my anesthesiology colleagues trying this out at an academic center. Any takers? Could be a great project for an aspiring and ambitious CRNA. I can write the trial protocol and potentially be the 6th author of 12. Figure out how to use a pediatric BVM for adults.
A 🎩 tip to the authors!
-EJ

Citation for Using a Pediatric BVM for Adults:

Siegler J, Kroll M, Wojcik S, Moy HP. Can EMS Providers Provide Appropriate Tidal Volumes in a Simulated Adult-sized Patient with a Pediatric-sized Bag-Valve-Mask? Prehosp Emerg Care. 2017 Jan-Feb;21(1):74-78. doi: 10.1080/10903127.2016.1227003. Epub 2016 Oct 3. PMID: 27690714.
Link to Article