"I don't think I'm very good at this intubation thing..."
Those were my thoughts as I left my first operating room clinical experience. It had been a long day, but mostly because of pure boredom. I had waited in the staff break room for about 7.5 hours of my 8-hour clinical shift. Almost all of the patients that day were receiving supraglottic airways, and I was only allowed in the room for endotracheal tubes. Finally, the last patient of the day needed an endotracheal tube - this was my shot! After hours of sitting in the waiting room reading my paramedic textbook, I was finally going to have my first shot at intubating a real human! I was incredibly nervous. I was escorted back, and the anesthesiologist handed me a Miller blade (which made me even more nervous).
me: "It is possible for me to use a mac blade?"
them: "I only ever use a straight blade, and that's what you'll be using as well."
I barely remember the next part, except a few things. The mouth was really difficult to open, and I barely got a view of anything. I thought I saw the interarytenoid notch, so I entered the airway with my ETT and stylet. I immediately lost my view of the airway. My tube had completely obscured my view, and I wasn't even sure where I was aiming anymore. I tried to reposition the blade, and I flailed the tube around for about 15 seconds before the anesthesiologist told me enough was enough. They took control, bagged the patient for a few seconds, and placed the tube themselves with extreme ease. I was excused and thanked for my time. It was a long car ride home.
Fast forward to field clinics and I was attempting to intubate a coded patient. I was using one of those old Glidescopes with the black and white screen. Guess what happened? I obscured my view of the airway with my tube again and got the camera full of crud from the airway in the process. Failed intubation. Again. Unreal.
You would think that I would have figured out the problem by now and fixed it in simulation, and I did try that. The problem was I was able to intubate the manakin with no problem at all. I wasn't able to figure out what the disconnect was between the manakin and a real patient. Eventually, with lots of practice and help from much better preceptors at my second OR clinical experience, I finally figured out what my problems were (problemS - plural).
It would take a long time to describe all the issues I had with my intubation technique, so I'll just focus on one problem for this blog that relates to bougie use.
Problem / Solution
The problem was that I was trying to go down the channel of the blade with my tube, almost like playing darts. I had no idea that you were supposed to approach the airway from the bottom right and aim up into the airway from there. This information helped, but I still wasn't completely satisfied. The anesthesiologists at my second OR clinical shift introduced me to the bougie, and I was blown away. (They also taught me about airway anatomy, positioning, and a progressive approach to the airway which helped a lot.) I felt like an intubating machine when I used a bougie because there was no issue of my tube obscuring my view. If the bougie could get an 18-year-old paramedic student with no experience some first-pass successes, it can work for anyone.
It's easy to see how you can obscure your own view with an ETT, especially if you're using direct laryngoscopy.
Back then I had never seen a bougie pre-loaded onto a tube - only the bougie introduced first, and then the endotracheal tube advanced over the bougie afterward by an assistant. It wasn't until years later that I saw people preloading their bougie in various ways. This seemed more suited to EMS where you usually don't have a lot of help at the head during intubation and space can be extremely limited.
Was the increase in the first-pass success that I experienced an isolated phenomenon? Let's take a look, and then we'll check out some bougie tips and tricks!
Does it actually work?
1988
We won't go any further back than the 80s, but in 1988, Kidd et al looked at the occurrence of clicks and bougie hold-up in difficult airways. The authors noted that "clicks were recorded in 89.7% of tracheal placements of the bougie. Hold up at between 24–40 cm occurred in all tracheal placements." It's good to know that there are other ways that the bougie can suggest you're in the trachea other than just being easier to visualize when it enters the glottic opening. This also tells us that the bougie has been thought to be a difficult airway adjunct for longer than many of us have been intubating. We'll touch on that 'hold-up sign' again in a second.
1996
Gataure, Vaughan, & Latto, did a study in 1996 that compared the bougie to stylet use in simulated difficult airways (grade 3 Cormack-Lehane view). The authors note that "after two attempts the tube was correctly placed in the trachea in 96% of cases in the Bougie First Group compared to only 66% of cases in the Stylet First Group (p < 0.001)." That's a pretty large gap, which resulted in a statistically significant difference in endotracheal intubation.
Cormack-Lehane Grades
2003
Heegaard et al performed a small study in 2003 that was published in the air medical journal. The authors note that the "overall success rate for first intubation attempt was 70% for the ETTI and 65% SOTI (P =.67). Total intubation time was 62 seconds (95% CI = 16-108) for the ETTI versus 62 seconds (95% CI = 38-86) for SOTI (P =.4). The ETTI group had a higher percentage of intubating difficult laryngeal views (grade 3 and 4) on first attempts than SOTI." ETTI = Endotracheal tube Introducer (bougie). SOTI = Standard orotracheal intubation. Even though the overall success rates were not very good (and the sample size was small), we see again that the bougie was associated with better success rates than the standard approach.
2008
Detave, Shiniara, & Leborgne conducted evaluated intubations over 8 years and looked at over fifteen thousand intubations (observational study). The authors noted that "out of 15,657 intubations, 301 of them were difficult. Eschmann's gum elastic bougie was used 276 times with a rate of success of 99%."
2012
Trouble in bougie paradise? Sahin et al published a couple of case reports in 2012 that looked at the damage caused by bougies. These were kind of special cases. One involved a Muallem ET Tube Stylet, which is a more rigid and malleable version of a bougie, and the other case report involved a standard Eschmann bougie. These were somewhat specialized cases, but they likely show that we have to be careful with the length and rigidity of a bougie since it can cause airway damage.
2014
Again with the complications??? Marson et al performed a simulation study in 2014 that evaluated the force needed to cause airway trauma while using the hold-up sign (lodging the bougie into a small bronchiole and feeling the resistance). This is a popular method of confirming placement into the trachea because the small bronchioles will provide resistance against the boogie while the esophagus is very unlikely to provide that same resistance. They express caution with this sign due to the potential for airway trauma, and in some cases (product specific) recommend directly against the use of this sign.
2017
Driver et al performed a study in 2017 that evaluated emergency department intubations with and without the use of a bougie. The authors note that "first-pass success was greater with than without bougie use (95% versus 86%; absolute difference 9% [95% confidence interval {CI} 2% to 16%]). The median first-attempt duration was higher with than without bougie (40 versus 27 seconds; difference 14 seconds [95% CI 11 to 16 seconds]). Bougie use was independently associated with greater first-pass success (adjusted odds ratio 2.83 [95% CI 1.35 to 5.92])." So, although the bougie took a little longer, it was still associated with higher first-pass success rates.
2018
Driver, Prekker, & Klein performed a study in 2018 evaluating intubations with at least one difficult airway characteristic, comparing the bougie and stylet. The authors note that "first-attempt intubation success was higher in the bougie group (96%) than in the endotracheal tube + stylet group (82%) (absolute between-group difference, 14% [95% CI, 8% to 20%])."
The authors continue with describing all-comers: "Among all patients, first-attempt intubation success in the bougie group (98%) was higher than the endotracheal tube + stylet group (87%) (absolute difference, 11% [95% CI, 7% to 14%]). The median duration of the first intubation attempt (38 seconds vs 36 seconds) and the incidence of hypoxemia (13% vs 14%) did not differ significantly between the bougie and endotracheal tube + stylet groups."
2020
Latimer et al performed a study in 2020 that evaluated paramedic performance across the Cormack-Lehane grades. The authors note that "paramedics attempted intubation in 823 patients during the control period and 771 during the bougie period. The first-attempt success rate increased from 70% to 77% (difference 7.0% [95% confidence interval 3% to 11%])."
A higher first-attempt success rate was observed during the bougie period across Cormack-Lehane grades.
No Bougie: 91%, 60%, 27%, and 6% (for grades 1, 2, 3, and 4 respectively).
Bougie: 96%, 85%, 50%, and 14% (for grades 1, 2, 3, and 4 respectively)
That's an absolute difference of 5% for Grade 1, 25% for Grade 2, 23% for Grade 3, and 8% for Grade 4.
The literature on bougie use is really not lacking. I recommend you read the literature for yourself and make your own decision. However, I will say that, I personally am convinced that bougie use improves first-pass success and is applicable to EMS.
The thought has traditionally been that you only break out the bougie only when you have a difficult airway. But... why wait? We are aware that as the number of airway attempts increase, so does the occurrence of complications. We should be doing everything we can to optimize first-pass success the first time we enter the airway. That sounds obvious, but it's frequently overlooked. Never assume the airway will be easy - go in thinking this will be the most difficult airway you've encountered yet.
Knowing what you know about the literature above, would you want intubation performed on you by a paramedic that wanted to 'give the stylet a shot' first? I'll pass - give me the bougie. But, how are we supposed to use this thing?
Tips
#1. Whatever grip you're planning on using (illustrated below), you should practice it in simulation many, many times before you attempt to use it on a real patient. Also, you'll want to add a level of realism to the simulation. Many people will simply grab the bougie, position it in their hand, and then intubate the manakin. However, is that how it goes in a real scenario? Not usually. Start with your hands occupied with a BVM, and then transition to your initial airway devices. Or if you normally have someone else bagging and then you come in to intubate, how are you opening the mouth and suctioning prior to tube placement? Get your rhythm down and try to be realistic about how these scenarios actually play out, because the method in which you plan to use your bougie might actually be more difficult than you thought.
#2. Know how to handle ETT advancement issues. The bougie is great, but it has an annoying habit of getting held up on the right-sided airway structures. The fix is simple - pull the ETT back slightly (while leaving the bougie in the glottic opening), and turn the bevel down, advancing it over the interarytenoid notch. This is accomplished by performing a counter-clockwise turn of the ETT, but I prefer just to speak about this method in terms of bevel direction (it clicks with people better). If you get stuck trying to advance the tube after it's in the glottic opening, you might want to try turning the bevel up if you're stuck on the anterior tracheal wall. This creates an obtuse angle between the ETT and the anterior tracheal wall.
#3. The front goes out front. I've seen in simulation that clinicians will often accidentally place the coude tip in the back. This isn't the end of the world, but it does leave you without the ability to use tactile feedback from dragging the bougie over the tracheal rings. It also might be more difficult to aim the bougie into the glottic opening without the coude tip out front. There is one exception to this rule that I've seen. If you're using a VividTrac VL, having the coude tip out front seems to land the bougie in the vallecula, which is an unusual problem. All other channeled blades I've used can have the coude tip out front and do not require flipping the bougie. Also, if you are using a channeled blade, make sure you have the tube in the channel along with the bougie - not having the tube in the channel can angle the bougie posterior and make aiming the bougie unnecessarily difficult.
Tricks
Here are all the methods I've tried so far for pre-loading the endotracheal tube onto the bouge (which I definitely recommend). If you guys know of any others, let me know and I'll try to include them! If you do choose not to pre-load your bouge and to simply use a Seldinger technique, keep a few things in mind:
Watch the tube advance, do not remove the laryngoscope after you pass the bougie into the trachea.
Position the patient properly - do not make the tube take a right or acute angle turn to get down to the airway. Use the ear-sternal notch / sniffing position in order to make the angle obtuse. (Easing the angle is also why you should keep the laryngoscope in the mouth.)
Advance gently - especially if you don't have a good view of what's occurring at the glottic opening.
Again, I personally don't think the Seldinger technique is a very good method. This is because of what I've witnessed in simulation. Clinicians tend to do the opposite of those three points above. They remove the laryngoscope, turn this into a blind technique, do not use a sniffing position/ear to sternal notch, and violently advance the tube when hold-up is felt. This is when I feel the pre-loaded options below are a better choice. However, as always, you should evaluate the literature yourself, and practice in simulation to see what works for you and is safest for your patients.
Simple Grip
This is an easy method to learn, but some people will criticize it because you're touching the cuff. The important part of this grip is to keep some tension on the bougie with your finger. This is because if you don't have any tension on the bougie, once you go into the airway and start bumping into things, the bougie will start coming out of the back of the ETT. This will leave you with no bougie on the front of the tube, which totally defeats the point.
Kiwi Grip
The Kiwi/Pistol grip is great if you practice with it. It looks simple, but I've had a lot of people struggle to learn it. To obtain this grip, you start off like the 'Hang Loose' grip above and then bend the back end of the tube into your hand. This makes the bougie pretty easy to steer, and the bend creates a decent amount of torque on the bougie that prevents it from slipping out of the back. Doctor Richard Levitan coined this one.
D-Grip
A closer look at the Murphy Eye
This is a nice setup if you're wanting something stable that you can be tucked back into the ETT package until you're ready to use it. Doctor James DuCanto stated using this adaptation of the kiwi/pistol grip. Depending on the length of the bougie, you might have to synch the adapter pretty close to the murphy eye in order to have enough bougie out front.
Smoke and a Drink
Side-by-side
I think I came up with this one, but someone else probably already does this and calls it something else. Either way, it's the smoke and a drink to me, and I'm sticking with it. This is a simple grip that doesn't require much dexterity. The pinky and the bend in the tube provide torque on the bougie so you don't lose it, and the grip itself provides a large range in motion for the wrist. Plus it has a cool name.
Conclusion
Regardless of what type of setup you use, practice with bougie-first intubation to give yourself the best shot at securing the airway on the first attempt. There are lots of options when you're using a bougie, but don't try any of them for the first time on a patient. You'll want to run these tips and tricks through in simulation many times prior to trying them in a real-life scenario.
I was going to end this blog in what I thought was a clever play on words...
"Is the airway bad? use a bougie."
But let's just leave it at... "Use a bougie."
Be sure to check out our EMS and Nursing Refresher as well!
References
Kidd, J. F., Dyson, A., & Latto, I. P. (1988). Successful difficult intubation. Use of the gum elastic bougie. Anaesthesia, 43(6), 437–438. https://doi.org/10.1111/j.1365-2044.1988.tb06625.x
Gataure, P. S., Vaughan, R. S., & Latto, I. P. (1996). Simulated difficult intubation. Comparison of the gum elastic bougie and the stylet. Anaesthesia, 51(10), 935–938. https://doi.org/10.1111/j.1365-2044.1996.tb14961.x
Heegaard, W. G., Black, C., Pasquerella, C., & Miner, J. (2003). Use of the endotracheal tube introducer as an adjunct for oral tracheal intubation in the prehospital setting. Air medical journal, 22(1), 28–31. https://pubmed.ncbi.nlm.nih.gov/12522361/
Detave, M., Shiniara, M., & Leborgne, J. M. (2008). Utilisation d'un mandrin d'Eschmann dans l'intubation orotrachéale difficile, évaluation d'une pratique professionnelle sur huit ans [Use of Eschmann's gum elastic bougie in difficult orotracheal intubation, an audit over eight years of clinical practice]. Annales francaises d'anesthesie et de reanimation, 27(2), 154–157. https://doi.org/10.1016/j.annfar.2007.11.006
Sahin, M., Anglade, D., Buchberger, M., Jankowski, A., Albaladejo, P., & Ferretti, G. R. (2012). Case reports: iatrogenic bronchial rupture following the use of endotracheal tube introducers. Canadian journal of anaesthesia = Journal canadien d'anesthesie, 59(10), 963–967. https://doi.org/10.1007/s12630-012-9763-z
Marson, B. A., Anderson, E., Wilkes, A. R., & Hodzovic, I. (2014). Bougie-related airway trauma: dangers of the hold-up sign. Anaesthesia, 69(3), 219–223. https://doi.org/10.1111/anae.12534
Driver, B., Dodd, K., Klein, L. R., Buckley, R., Robinson, A., McGill, J. W., Reardon, R. F., & Prekker, M. E. (2017). The Bougie and First-Pass Success in the Emergency Department. Annals of emergency medicine, 70(4), 473–478.e1. https://doi.org/10.1016/j.annemergmed.2017.04.033
Driver, B. E., Prekker, M. E., Klein, L. R., Reardon, R. F., Miner, J. R., Fagerstrom, E. T., Cleghorn, M. R., McGill, J. W., & Cole, J. B. (2018). Effect of Use of a Bougie vs Endotracheal Tube and Stylet on First-Attempt Intubation Success Among Patients With Difficult Airways Undergoing Emergency Intubation: A Randomized Clinical Trial. JAMA, 319(21), 2179–2189. https://doi.org/10.1001/jama.2018.6496
Latimer, A. J., Harrington, B., Counts, C. R., Ruark, K., Maynard, C., Watase, T., & Sayre, M. R. (2021). Routine Use of a Bougie Improves First-Attempt Intubation Success in the Out-of-Hospital Setting. Annals of emergency medicine, 77(3), 296–304. https://doi.org/10.1016/j.annemergmed.2020.10.016
Upcoming:
Driver B, Semler MW, Self WH BOUGIE Investigators# and the Pragmatic Critical Care Research Group, et al
BOugie or stylet in patients UnderGoing Intubation Emergently (BOUGIE): protocol and statistical analysis plan for a randomised clinical trial
BMJ Open 2021;11:e047790. doi: 10.1136/bmjopen-2020-047790
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