I apologize for cross posting, since this has come up a lot recently on some of those "other" EMS networking websites, but there's a great discussion about the King Airway at EMS Garage, episode 11. Download and fast forward to 26:05. Apparently Wake County EMS uses the King LT airway as the advanced airway of choice (not mandate) in up to 80% of their cardiac arrest patients. They can also claim a 37% rate of neurologically intact survival to hospital discharge (49% in the City of Raleigh). Obviously they're doing something right!
We use an ETT for all advanced airways. If an ETT is unsuccessful we switch to the King. In my opinion it is alot better due to only one tube to vent through. I have intercepted BLS units and they were venting through the wrong tube. Without frequent use and/or frequent training, some people forget how it works. This could be said about any skills that are allowed though.
I'm not convinced a simpler airway is the best way to solve a training problem. If your EMT's are not smart enough to use a Combitube, should they be using a simpler airway or be better trained on the dual-lumen type airway?
The King airway is really little more than an updated EOA. The only difference is it has an pharyngeal balloon instead of an external mask. They are both SINGLE lumen airways - which translates into fewer options.
For example, if once inserted the King does not work - you are done. Time to pull it out. But if the Combitube or Easytube does not produce ventilation on the primary port - you have a backup. You then can try the second lumen and likely take your WORST possible airway scenario (a plugged trachea), and turn it into the OPTIMAL airway - an intubated and tracheal ventilated airway.
Another way to phrase the same observation is that if your EMT's are too stupid to use an EOA - do you need a simpler airway or a better EMT? The Combitube and Easytube both afford EMT's an important second option when the primary option fails.
The real surprise to me - is that so many Paramedics seems to want fewer options too. Is the dual-lumen type rescue airway really too sophisticated for today's Medics?
When theory collides with reality, I'll take reality every time. The reality is that Wake County EMS has validated the King airway as an extremely effective primary advanced airway for cardiac arrest patients. Again, not of mandate, but of choice. They can intubate the trachea if they want to, and their skills monitoring and quality control are superior to most. Speaking for myself, I don't want fewer options. What I want is compliance with evidence based guidelines. I don't think the problem is stupid paramedics. I think the problem is inadequate oversight. Even if the problem of poor medical direction is solved, if your patients do better with the King than with a tube in the trachea, why would you put a tube in the trachea? The truth is that most EMS systems don't measure their clinical performance, so they don't know whether or not their helping or harming their patients. So they fall back on how they feel or what their theory is. I personally think it's time for EMS to grow up and start measuring.
Then the reality that the King Airway is not an "advanced airway" (it's a rescue airway), PLUS the fact that there is no evidence that it is better than an ETT - should make a positive impact on your clinical practice.
The fact that the Combitube and Easytube provide an important second ventilation option is not a theory. It's a reality based on these devices physical structure. Your statement that because Paramedics in one geographic location find the King airway "better" is not a reality - it's a theory based on anecdote.
Do they think it's better because it does a better job of protecting the lungs from aspiration? Or do they think it is better because it's "easier"? WHY do they choose to use it so much?
I've met a few Medics from Wake County, and every single one of them can run circles around me. So I will keep my mind open, should they ever publish a study of their findings on this important aspect of patient care.
Until then, the reason I will continue to advocate for the gold standard of airway management is because the anecdotal evidence supporting one regions use of the King is not enough to undo decades of evidence substantiating the clinical efficacy of endotracheal intubation.
Why would I put a tube in the trachea? Because the evidence says it as the best airway.
To quote their EMS Chief in a recent EMS Garage podcast:
"I will tell you that based on the data that in our service the medics themselves are using the King airway as the airway of choice in cardiac arrest 80% of the time because they can have the airway in and the patient ventilated in the time that it takes to unfold the laryngoscope and put air in the syringe for the ET tube. Of choice; not of mandate, and not throwing the laryngocope and ET tubes off the ambulance. Same thing -- low and behold -- in cardiac arrest with IV access. You come to our system and run the next 25 cardiac arrests and if you see somebody with a catheter in their hand, you'll be with somebody who's probably a very tenured paramedic, because the rest of the folks will have two EZ-IOs in before you can unwrap the manual catheter. So, when you said you think it's an inferior airway method, our belief is that the data shows to the contrary; that patients who get a King airway have better outcomes, and our data shows that."
The gold standard is the neurologically intact survivor walking out of the hospital. Wake County EMS can claim a 37% survival rate (Utstein template) and 49% in the City of Raleigh.
To clarify, the evidence based guidelines state:
"Tracheal intubation, once the "gold standard" of assisted ventilation, remains the advanced airway of choice only for experienced providers who working in programs with careful performance monitoring, defined requirements for skills maintenance (e.g., establishment of minimal number of intubations to be accomplished per year), and an atmosphere of continuing quality improvement [...] In the absence of quality improvement programs, the probability of lethal complications from tracheal intubation become unacceptably high."
I have no problem with ETI. If you follow the ECC guidelines. Does your EMS system observe careful performance monitoring? Do you QA/QI every intubation attempt? Is there a defined requirement for skills maintenance? Do you rotate through the OR if necessary? Are you breathing in the sweet atmosphere of continuing quality improvement? In that case, ETI may be the best airway.
Then again, maybe not for out-of-hospital cardiac arrest.
Incidentally, the AHA refers to the LMA and Combitube as alternative advanced airway devices. You don't think the King qualifies? Why not?
So then they like it better because they think it's faster. Not because it is better, by the quotation you provided. Faster does not automatically make it better.
Evidence of improved outcomes in the EMS System overall, is not evidence on the airway device by itself. Are you claiming that the King Airway is why this system has experienced improved outcomes? Or was the the EZ IO that reduced mortality? Or could it be because they improved their scene response times? Or implemented an improved first-responder program? Only when all variables are carefully controlled, can one draw any reasonable conclusions.
Incidentally, the AHA refers to the LMA and Combitube as alternative advanced airway devices. You don't think the King qualifies? Why not?'>>
Because it is an simple single-lumen obturator airway, long-held as a BLS level airway device. It was the first airway (other than an OPA) that I used as an EMT in the 1970's. If it was an ALS device, almost every state in the union would not have already classified EOA's as an EMT level skill. Remember, the King Airway is by it's very structure and design, an esophageal obturator airway.
The plain truth is that it's more likely because the King was still pretty new when this was written. It often takes a while for these things to trickle into the AHA guidelines. I actually don't think that the LMA or Combitube are by their design - advanced airways either. Neither use a rigid instrument of insertion or is intended for placement into the trachea. In many states the Combitube is a BLS skill, since it's a simple blind technique. The LMA is a type of "mask" that is placed inside the mouth rather than around the outside of the mouth.
You don't really drill 200$ worth of IO holes in every dead guy you meet do you? Who pays for this "convenience"? The poor mans family? I know the insurance carriers won't. I honestly think I CAN unwrap an IV catheter faster than you can place two IO's. In fact, I would bet a considerable sum of money I can drop an EJ line faster most of the time, and for 99$ less money with 99% fewer potential complications. C'mon, admit it - you do it because it's a cool new toy, right?
Please ask any anesthesiologist what the "Gold Standard of Airway Care" is. If even one tells you it's about patient discharge outcomes, please let me know?
I don't mind a guy having a different opinion than mine, as long as he or she can argue the case with some intelligence. You certainly have and I have really enjoyed it.
I just looked up the King's FDA 510K at FDA.gov. The manufacturer seems to agree with me. They do not claim this is an advanced airway. In fact, quite the opposite. They claimed that it is substaintially equivalent to an oropharyngeal airway.
I don't mind a guy having different opinions either, Dan! Honestly, I think terms like "basic" and "advanced" are pretty meaningless in this day and age. In some areas of the country, EMT-basics are allowed to intubate. Does that make tracheal intubation a "basic" skill or a "basic" procedure? I don't think so. If the fact that the King LT is a blind insertion device makes it a basic airway, I can live with that. The only question that matters is whether or not it works.
I don't personally drill IO holes in anyone. My EMS service just got the EZ-IO in the last 12 months, and I have not had occasion (or need) to use it yet. In fact, I saw no need for the device in the beginning, and wished we had spent our money on something else (like CPAP). You don't know me, but I don't use anything "because it's cool" and I think less of paramedics who do. However, I'm giving it a second look based on the results in Wake County. I'm quite aware that no medications have been proven to change 30 day mortality in the cardiac arrest patient. On the other hand, only the most elite EMS systems in the world can claim a survival rate of 37-49%. If they're dropping a King and a couple of IOs in the first minute or two of the arrest without interrupting compressions, who am I to criticize them? The last thing I want my mother or father's paramedic to consider when treating a life threatening emergency is how much the equipment costs.
I'm not sure why you ignored the part where I conceded that tracheal intubation was the airway of choice for experienced providers with strict quality controls and defined requirements for skills maintenance and an atmosphere of continuing quality improvement, but that's the vital piece of information that makes your comparison of paramedics to anesthesiologists irrelevant. Unless, of course, you're claiming that there's no difference between the average paramedic and the average anesthesiogist when it comes to airway management.
Regardless, paramedics and anesthesiologists have different jobs. Out of hospital cardiac arrest is a unique animal, and the gold standard of resuscitation success is survival to hospital discharge. If the King LT helps minimize interruptions to chest compressions, and if continuous chest compressions are the key to saving people in cardiac arrest, then the King LT may be superior to tracheal intubation for this set of patients, even if you concede that the paramedics are skilled at laryngoscopy.
As for the survival rates in Wake County, I agree that it can't all be attributed to the King LT airway, and I never said that it could. I'm paying attention to everything they're doing right. What I see Wake County EMS doing is taking the evidence based guidelines to their logical conclusions, whether it's the reduced emphasis on tracheal intubation, the importance of uninterrupted chest compressions, the impedence threshhold device, induced hypothermia, and so on.
What I see many other EMS systems doing is fighting the guidelines. When I say fighting the guidelines, I'm talking about resistance to change. In the last analysis, there is no higher standard than whether or not an EMS system returns patients to their families. I hope we can agree on that!
I held off on adding to this section...but wanted to look at the theory and physiology that may be behind the higher success rates in Wake County...and others that have started using the King Airway in cardiac arrest.
During cardiac arrest patients enter a state of low-flow (no flow) of blood and acid builds up, placing the person in acidemia. When acid builds up cardiac contractile function is decreased, probably due to impaired oxidative phosphorylation (decreased ATP production) and intracellular acidosis. Acidosis causes the VF threshold to fall, increasing the likelihood that this rhythm or asystole will be the initial presenting rhythm during cardiac arrest, and subsequently acidosis increases the defibrillation threshold. This is the reason that a one shock scenario is in the algorithm and no longer 3 stacked shocks. If they do not convert on the first shock, then they are probably in acidemia. High quality CPR is needed to correct the blood flow issue, and quality ventilations (without hyperventilation) are needed to begin the process of correcting the acidemia. In cardiac arrest we are combating three known issues; 1) Respiratory insufficiency 2) No flow state (blood) 3) Respiratory acidosis (pre arrest metabolic could be an issue).
The treatment of acidosis reflects that of the underlying disorder, but particularly emphasis should be on restoration of normal tissue perfusion and oxygenation. In the case of cardiac arrest, many places are taking a simple, logical and sensible approach. They are providing "high quality CPR" for tissue perfusion, and oxygenation through placement of a quickly established airway (King Airway). Intubation takes time and skill, as much as 30-90 seconds goes by without adequate compressions in the best case scenario. Then you have many more issues with dislodgement during compressions and movement (if you transport cardiac arrest with CPR in progress).
The treatment with placement of a King Airway begins the treatment for primary respiratory acidosis, therefore increasing the VF threshold, and lowering the defibrillation threshold....
Boy...am I glad we are no longer in the days of "Sodium Bicarb" as the first line drug..... although some swear by it.....there were never results like we are seeing in Wake County...but buffer therapy is another discussion.
You are correct; HIGH QUALITY CPR is best thing we can do for the cardiac arrest patient. CPR, electricity, and airway management, in that order. As for the Sodium Bicarb,
We all know what happens when you shock a patient in "fine fib", Asystole follows shortly. When you shock a patient with course V-Fib you are more likely to have a viable rhythm post shock. The only two things that are proven to "coarsen fib" are high quality CPR and vasoconstrictors.
(Hence the reason we use an IO for quick initial vascular access and a King, for airway control if the BVM isn’t sufficient, (so no one stops CPR to intubate) in a cardiac arrest in Wake County.)
Since we, first responders to ED Doc's, now know how to do CPR, "Hard, Fast and Uninterrupted" we are getting more patients with ROSC and therefore more patients discharged neurologically intact.
If you think about it, in the "days of Sodium Bicarb" we where stopping CPR to intubate immediately, then hyperventilating the snot out of the patient, filling the thorax with air and decreasing blood flow from the Vena Cava, stopping CPR before and after each shock to "see what we had" and shocking the patient 3 times as much with "stacked shocks".
Also we were giving Sodium Bicarb for the wrong reasons, yes acidosis is a bad thing but 1-2 amps of Sodium Bicarb is going to fix that much, nor should we be worried about it that much with in the first 24 hours after the initial arrest. Now that we know how to do CPR, Sodium Bicarb may not be such a bad idea; obviously it contains a significant amount of sodium, which is a GREAT vasoconstrictor, and an electrolyte that cells need to function properly.
I said all that just to say, don’t be surprised if you begin seeing the old ways come back again, (High dose Eppi, first line Sodium Bicarb, Etc.)
Now that we are doing the basics right, we don’t know don’t know if the "advanced" stuff we tried in years past didn’t work because it truly didn’t work, or if it was because we didn’t know how to do CPR.
PS. If anyone has any questions as to why Wake County does what we do feel free to contact me at email@example.com