Preoxygenation

[E tank]

Well yeah, that's all basic stuff in any trauma center or tertiary facility ED. Our ED has most of that stuff (minus the bronchoscopes). But on the medical / surgical floor in a rural 30-bed hospital…..not so much.

Well, with the advent of disposable bronchoscopes (Ambu...they suck, but for gross anatomy identification and tube placement, they're a C+) bronchoscopes are in everyone's wheel house now...you ought to look into them. Not anywhere near actual fiber optic scopes (a processed image, not an actual view/picture) but, like cold pizza, better than no pizza.

 

[Carlos Danger]

Well, with the advent of disposable bronchoscopes (Ambu...they suck, but for gross anatomy identification and tube placement, they're a C+) bronchoscopes are in everyone's wheel house now...you ought to look into them. Not anywhere near actual fiber optic scopes (a processed image, not an actual view/picture) but, like cold pizza, better than no pizza.

That’s pretty cool. I’ll look into it. What I’d give my left testicle for is the C-Mac system with the flexible scope. But with those being so pricey and our whole system being on Glidescope, I’ll never get the C-Mac.

We have an old Storz that I get out and play with every once in a while, but getting it cleaned is a PITA so I don’t practice with it nearly as much as I’d like to.

 

[Colt45]

Pre-oxygenation before an intubation attempt is mandatory and the most important part of intubation besides landing the tube itself. It's amazing to see just how long a patient will stay in the upper and mid 90,s iv you do it properly. And dont worry about giving a few breaths to quickly. Obviously dont sit there and bag them every second for a full 30 seconds, but 5-10 seconds at the end of your pre oxygenationwill increase the amount of time you have to land the tube significantly. This last tidbit was per multiple Anesthesiologists I've worked with.

 

[Carlos Danger]

Pre-oxygenation before an intubation attempt is mandatory and the most important part of intubation besides landing the tube itself. It's amazing to see just how long a patient will stay in the upper and mid 90,s iv you do it properly. And dont worry about giving a few breaths to quickly. Obviously dont sit there and bag them every second for a full 30 seconds, but 5-10 seconds at the end of your pre oxygenationwill increase the amount of time you have to land the tube significantly. This last tidbit was per multiple Anesthesiologists I've worked with.

That does not apply to the emergent RSI. It is only true of patients who are NPO.

 

[VFlutter]

Also most of the time they are bagging through a circuit and are much more skilled at giving appropriate TV at appropriate pressures. Not true of many other providers.

 

[E tank]

Pre-oxygenation before an intubation attempt is mandatory and the most important part of intubation besides landing the tube itself. It's amazing to see just how long a patient will stay in the upper and mid 90,s iv you do it properly. And dont worry about giving a few breaths to quickly. Obviously dont sit there and bag them every second for a full 30 seconds, but 5-10 seconds at the end of your pre oxygenationwill increase the amount of time you have to land the tube significantly. This last tidbit was per multiple Anesthesiologists I've worked with.

Hand ventilating after induction/paralyzing agents is most usually for the purposes of gas exchange while waiting for full effects of the agents to occur. But you're right, not hand ventilating during that period of apnea will most definitely shorten the time to desaturation during DL attempt(s). As stated above, not for RSI type scenarios.

 

[Colt45]

Hand ventilating after induction/paralyzing agents is most usually for the purposes of gas exchange while waiting for full effects of the agents to occur. But you're right, not hand ventilating during that period of apnea will most definitely shorten the time to desaturation during DL attempt(s). As stated above, not for RSI type scenarios.

Good to know. I should have been more specific, but RSI is something that isn't common where I'm from as a medic. Currently only one or two departments do it. So I have not had much experience with it, especially with the paralytic.

 

[MSDeltaFlt]

What's your protocol requirement for preoxygenation and/or apneic oxygenation (if any) prior to and/or during intubation attempts?

What ought it be?

To not let SAT's drop below 90% or drop more that 5 points if already less than 90%

 

[CWATT]

OPA + 2 NPAs + NRB (15 lpm) + N/C (15 lpm) or BVM (15lpm) + N/C (15 lpm) for 2-3mins to achieve SpO2 >95% (target 100%) terminating attempt @ 93%.

I'm not personally sold yet that using NC during the intubation helps in the patients we are most likely to need it to help with, but it may help and isn't going to hurt, so I think it is probably a good practice.

Can you elaborate more on this please?




- C

 

[CWATT]

*double post*.

 

[Bullets]

My BLS agency: OPA/NPAx2 + NRB/NC @ 15lpm for the 1st 10 minutes on scene then BVM/PEEP until ALS gets there or ALS tells them to do something different.

ALS gig: BVM/PEEP + NC 6-15lpm for intubation

 

[E tank]

My BLS agency: OPA/NPAx2 + NRB/NC @ 15lpm for the 1st 10 minutes on scene then BVM/PEEP until ALS gets there or ALS tells them to do something different.

ALS gig: BVM/PEEP + NC 6-15lpm for intubation

Very surprised at the liberal use of NPA's in patients being prepared for intubation. With so many patients on some type of "blood thinners", that is asking for a very bloody airway. Not sure you gain that much more than with just a properly sized OPA alone.

 

[Carlos Danger]

Can you elaborate more on this please?

- C

Tl:dr; I think leaving a NC in place at high flows during airway management attempts is a good practice because it may help significantly, but I wouldn't count on it doing much in a sick patient, which means it's utility when you need it the most is possibly very limited.

What I mean is that apneic oxygenation only works if the oxygen can flow passively into the lungs, and then diffuse readily across the alveolar-cappilary membrane into the blood. When those things happen, apneic oxygenation works well. The thing is, if those things are happening it means the patient has reasonably normal anatomy and lungs that are working well, which means the airway was probably not going to be difficult to manage in the first place, which means apneic oxygenation probably didn't make any difference.

The patients who we really need apneic oxygenation to work in are the ones who are going to be difficult to manage. An airway can be difficult because of anatomical or physiological factors. Anatomy-wise, I'm not even talking about people with severely abnormal anatomy due to facial trauma or a a congenital syndrome like Pierre-robin. I'm talking about obesity, which will result in passive airway obstruction and physically prevent the oxygen from flowing into the trachea. Physiologically, anything that inhibits gas exchange for any reason (advanced COPD, severe pneumonia, severe OSA, ARDS, or any other cause of v/q mismatch) or causes atelectasis will limit the effectiveness of apneic oxygenation.

 

[TXmed]

Very surprised at the liberal use of NPA's in patients being prepared for intubation. With so many patients on some type of "blood thinners", that is asking for a very bloody airway. Not sure you gain that much more than with just a properly sized OPA alone.

@E tank, While yes i do agree with you that it can create bleeding for patients on blood thinners, and in your anatomically simple airway patient, may be overkill. I actually am an advocate for this and am pleased to hear other people do this as well. This is great preparation on patients that are overweight to obese. Dual use NPAs coupled with OPA can have a huge benefit on proper ventilation of these patients in the pre-hospital setting where positioning, # of hands, and overall situation can be difficult. Just my opinion though.

 

[E tank]

Dual use NPAs coupled with OPA can have a huge benefit on proper ventilation of these patients in the pre-hospital setting where positioning, # of hands, and overall situation can be difficult. Just my opinion though.

Hard to argue with increasing airway diameter with more conduit. It is simple math. I'd just say that a careful review of the med list would be warranted and a good risk/benefit determination made. You might do that with a patient on warfarin if you thought it would better than not doing it. You'd just have weighed the consequences with your objectives.

 

[CWATT]

@TXmed @E tank — My ‘objection’ to the OPA + dual NPA ethos is the NPA by its very nature and the way we size it terminates in the upper oropharynx which anatomically contains bony supporting structures. My understanding is the upper airway obstruction seen in obese persons are in areas lacking these supporting structures, namely the lower oropharynx / laryngopharynx where the weight of adipose tissue collapses the airway during times of decreased muscle tone. The only airway adjunct we use to maintain patency of this area is the OPA.

The NPA inarguably presents benefits in situations of lower facial trauma or trismus where manipulation of the mandible may not be possible and the mouth opening insufficient to allow insertion of an NPA, but as routine practice I think the ‘benefits’ outweigh the costs.

*I’m fully open to discussion here*

 

[E tank]

@TXmed @E tank — My ‘objection’ to the OPA + dual NPA ethos is the NPA by its very nature and the way we size it terminates in the upper oropharynx which anatomically contains bony supporting structures. My understanding is the upper airway obstruction seen in obese persons are in areas lacking these supporting structures, namely the lower oropharynx / laryngopharynx where the weight of adipose tissue collapses the airway during times of decreased muscle tone. The only airway adjunct we use to maintain patency of this area is the OPA.
The NPA inarguably presents benefits in situations of lower facial trauma or trismus where manipulation of the mandible may not be possible and the mouth opening insufficient to allow insertion of an NPA, but as routine practice I think the ‘benefits’ outweigh the costs.

*I’m fully open to discussion here*

I don't at all disagree with you here. I agree that in some patients, NPA's superimposed on a properly sized OPA is kind of redundant and not worth a very bloody and therefore more difficult airway. That said, in those patients with a history of obstructive sleep apnea, a lot redundant airway tissue, thick neck, excessive head fat (yeah, thats a thing) NPA's could present an advantage when combined with an OPA

 

[TXmed]

@CWATT a properly placed NPA will terminate a where the oropharynx begins to turn into the laryngopharynx, usually right before. This helps facilitate ventilation past the tongue mainly.

People often forget that OPAs in its self is obstructing some ventilation (still use OPA's when indicated). What i am advocating, is for the occasional intubator to use NPA+OPA+ jaw thrust+ 2 hand seal on BVM+ PEEP valve + NC@15lpm in an effort to maximize oxygenation and ventilation. I emphasize the term maximize because you want more than "just good enough" if you have to BVM someone in case of a missed attempt. Just creating good habits for people who do not do this very often.

 

[CWATT]

appropriate

@CWATT ...in an effort to maximize oxygenation and ventilation.

What do you mean by ‘maximize’? If you are achieving adequate tidal volumes with an OPA and SPO2 is 100% (or whatever standard your protocols call for or patient pathology allows for), what is there to ‘maximize’ with the addition of an NPA? I can see an argument being made for ensuring nasal patency for the N/C, but those hemoglobin aren’t about to get any more saturated than 100% if you’re already there. Or are you thinking it’s better to run NPAs and know you have flowing O2 than find out 2-minutes into an unanticipated difficult airway that you’re desating quicker than you thought because it isn’t patent.... Hrm...

If this is where you’re coming from, I could see it being ‘routine’ for perceived difficult airway, obese patients, or underlying pulmonary pathologies where desaturation would occur more rapidly. But for an otherwise healthy person, I’m just not sold on the practice. Then again, you did state ‘routine for people who do not do this very often’... Argh. Medical discussions. So many considerations to make.


*side note — that NPA drawing you posted is demonstrating the procedure incorrectly. The NPA should be inserted along the floor of the nasal passage at a downward 10-15deg angle, where that drawing shows it going upward, directly into the area of the middle turbinates.

 

[TXmed]

@CWATT I think you are reading more into this than what i mean.

Im just advocating for good habits and preparedness. Once you start going down hill on the dissociation curve its hard to climb up it.