This is the post version of a talk in the airway workshop for PACSA 2019 in Johannesburg. A lot of the references and thinking underpinning this came from this post.
We talk about the risky bits of anaesthesia all the time. We talk about the take-off, and the landing. I guess the middle bit where the surgeons are doing the clever ‘nothing heals like steel’ routine is just a given.
The literature does not talk about this. The literature talks about take-off. Take-off, take-off. Launch, take-off, giddy up. Video, cric, needle, take-off, fatigue. Landing. Take-off, biomarkers of questionable clinical utility, THRIVE, take-off.
It’s a failing.
It’s sort of a failing of evidence to line up with what we actually need in practice. Perhaps it’s because it’s just not really that cool. The end bit is sometimes a little messy and generally a little, well, less controlled than the start. Safe, but not always smooth.
Plus it’s harder to measure *cool things*. There’s no POGO score or airway grading. There’s no stopwatch that makes the A+ ticking noise like when the bomb is counting down on the midday movie. Measuring bits that are real world meaningful is sometimes a bit inelegant and just not cool.
So we sit here. Waiting. Take-off. THRIVE.
Patients want us to do the end bit well though.
So maybe we should think about a plan.
Plans for the End Times
Yes the apocalypse is coming because we’re all burning coal so you should plan for that. No one wants to carry around a welping demon on their shoulder for eternity because they forgot to plan.
Oh, also extubation. We should plan for extubation.
Actually the adults DAS types have already got an extubation plan. It looks pretty good.
For today let’s forget about adults at the end times. (Particularly seeing as in my tenuous ‘End Times’ construction adults are responsible for the disintegration of our potential future society so really screw all of us.)
So we should plan whenever it seems like we need a plan. When’s that? Well probably just when the patient has any version of a difficult airway. That includes difficulty with face-mask ventilation and difficulty with intubation and difficulty with any other technique or part of the clinical scenario. Even if it was just difficult for the first time today. A plan will help.
So how do we make that stick?
The memorable bit
Well at the paeds airway course we now run this is pretty much what we’re going with.
Definitely don’t look at the first letter of each of those words and put them together. Also don’t think about robots on wheels. No robots on wheels. If you do picture a robot on wheels, it’s definitely a robot that speaks an intelligible language you can easily pick up. There would not be random electro-noises. No.
So let’s take them one-by-one:
It is what it says. First step is to understand the risk plus any things we can do about that risk.
So with this step it’s worth looking at:
- What pre-existing conditions or information suggest the patient could be challenged by the whole extubation process?
- Again these relate to things that might increase the risk of difficulties with oxygen or ventilation by any means, or things that would make you say this is a ‘difficult airway’ at the start.
- Such factors obviously include failed extubation on previous occasions, patients who require non-invasive ventilation in their usual care, patients who can’t manage secretions well and anyone with neuromuscular, cardiovascular, or respiratory illnesses.
- Are there risk factors that have just become an issue with this episode of care?
- This therefore includes patients who have just declared themselves as having a difficult airway for the first time.
- Any new airway pathology counts (including any iatrogenic trauma, airway oedema or other thing that makes that airway narrower). So does any acute respiratory pathology that might make maintaining oxygen targets at the end.
- Prolonged mechanical ventilation likewise can be considered as contributing new issues.
- What about access to the airway? If you have a patient with a new thing challenging access to the airway (say halo traction or mandibular fixation) then that counts as a new issue to make life difficult.
- Do you need more information? Would knowing more influence your consideration of how risky things are? This may be as simple as exploring the patient’s history an prior experiences more. Perhaps information from another practitioner would help you understand things. Or is it necessary to look in the forms of invesigations, or endoscopy, or even just checking the oropharyngeal and nasopharyngeal structures with a quick look with a nasendoscope or laryngoscope?
- Finally think about the reversible factors. Is there scope to make the airway less narrow with steroids or time? Can you optimise respiratory status in a meaningful way. Is there neuromuscular weakness or oversedation to think about?
OK. Once we know the risk profile we can get ready to do the actual thing. So at this point:
- What people are required?
- The team involved might need modification (hello ENT friends and hello friendly other anaesthetist).
- What location should the extubation occur in?
- Maybe the theatres is the natural environment you’d like to work in.
- What time should be on the clock?
- It seems pretty sensible, wherever feasible, to do this earlier in the day so that if issues arise later, it’s still the day.
- What equipment is required?
- This applies both to special equipment for any planned supports after extubation, and for the next bit. It also includes simple things like suction, working IV access, the right face-mask and circuit, airway adjuncts and maybe a nebulilser mask in case you need a little adrenaline.
- What is the reintubation plan?
- If it’s difficult enough to plan for the extubation, a plan to put that tube back in is really sensible.
Crunch time. Given the planning that has already happened this should be a walk in the park. At least part of the ‘do’ bit is also communicating so everyone involved shares the same plan. So for this bit we should think about:
- Any planned procedures happening at the same time. The classic here is rigid airway endoscopy by ENT which then proceeds to extubation.
- Go/No Go. This just means declaring up front how you’ll assess that the patient is ready for a trial of extubation (and with recent work showing the value of things like grimace, purposeful movement, conjugate gaze, eye opening or adequate tidal volumes there is actual evidence that helps here), or the things that would say ‘Stop. Turn back. You are going the wrong way. At least right now.’
- What’s your first support option? Is it you with a way of delivering CPAP. Is it humidified high flow nasal cannulae running oxygen? Is it the patient’s usual non-invasive ventilation. It’s part of ‘do’.
- What targets do you want to maintain to be happy that you’re in a good place and reintubation isn’t necessary? Is there a specific saturations number, or a particular clinical sign to look out for, or blood gases you’ll be checking? Declare it early and make sure everyone knows what it is.
You got this far? High fives. Leave the building. Smash that coffee, you earned it.
Except the patient needs a comprehensive plan to keep them going well and your colleagues need things tidied up both for now and later.
So where will the patient be looked after once you’ve got the extubation done? Will there be enough people around to keep an eye on them?
How are you going to get them there? Safe transfer is really important.
Who is going to be looking after them and who do you need to hand over to? Handovers should be person-to-person and undertaken both with the patient who will be looking after the patient out there, and whichever one of your colleagues is likely to get a call about them if there are issues later.
What’s the ongoing respiratory plan? What other elements of care do you need to sort as well (things like analgesia, fluids or post-surgical things).
Finally document everything. Colleagues will be pleased you did.
And that’s pretty much it for a suggested plan. It doesn’t replace the need for more evidence but it does turn up the volume on the bit we claim matters, that we just don’t chat about enough. The end.
Most of the references underpinning this thing on extubation can be found on this thing related to an older talk.
There is the additional one about extubation signals which you can find here:
Templeton TW, Goenaga-Diaz EJ, Downard MG, et al. Assessment of Common Criteria for Awake Extubation in Infants and Young Children. Anesthesiology. 2019;131:801-8.