The Great Prehospital Airway Debate

… is over! With another 12,000 patients included in two prospective, randomized trials, we’ve finally arrived at unassailable conclusions regarding optimal airway management in the context of out-of-hospital cardiac arrest.

Or, as usual, not.

These two trials, AIRWAYS-2 from the United Kingdom and PART from the United States, randomized paramedics and emergency medical services agencies to routinely providing either endotracheal intubation or a supraglottic airway. The details of both trials are a little bit different, but they are both effectively pragmatic approaches directing the first attempt at airway management in patients deemed eligible in non-traumatic OHCA.

AIRWAYS-2 enrolled over 9,000 patients while PART enrolled over 3,000, and their results were similar, but not precisely the same. The primary outcome for AIRWAYS-2 was “good outcome” (0-3) on the modified Rankin Scale at 30 days, which was achieved by the ETI cohort in 6.8% versus 6.4% with SGA. The primary outcome for PART was 72-hour survival, which was 15.4% in their ETI cohort versus 18.3% with SGA. For rough comparison’s sake, PART also recorded mRS at hospital discharge, which was 5.0% with ETI and 7.1% with SGA.

These are both incredibly messy trials with regard to delivery of the intervention. Substantial fractions of both cohorts in the AIRWAYS-2 trial did not ultimately receive an attempt at an advanced airway, including over a quarter of those randomized to ETI. Then, the success rate for ETI in PART was only 51%, as compared with 90% with SGA. It is an imposing task to parse through their flow diagrams of randomization, patient interventions, and outcomes in both the main body of the articles and in the supplemental material.

Ultimately, while these can be argued back-and-forth due to substantial underlying uncertainty, there is little evidence to suggest ETI should be favored over SGA. This ought not be terribly surprising, as we’ve already seen a trial of ETI versus bag-valve mask ventilation which was unable to conclusively support one method over the other. While these findings probably could be used to substantially affect paramedic training and procedures with respect to ETI, the better, remaining question is whether any advanced airway should be routinely attempted at all.

“Effect of a Strategy of a Supraglottic Airway Device vs Tracheal Intubation During Out-of-Hospital Cardiac Arrest on Functional Outcome: The AIRWAYS-2 Randomized Clinical Trial”

https://jamanetwork.com/journals/jama/fullarticle/2698493

“Effect of a Strategy of Initial Laryngeal Tube Insertion vs Endotracheal Intubation on 72-Hour Survival in Adults With Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial”

https://jamanetwork.com/journals/jama/fullarticle/2698491

6 thoughts on “The Great Prehospital Airway Debate”

  1. We continue to have no evidence that ventilation improves outcomes from cardiac arrest – except when the arrest has a respiratory origin.

    People providing chest compressions do not appear to have any trouble telling when the arrest has a respiratory origin.

    We continue to make excuses for using a harmful, rarely practiced, invasive procedure, with only one benefit – it makes the medic feel good.

    We need to stop pretending we know what we are doing, because the evidence keeps showing us that we don’t know what we are doing.

    We need to start doing what is best for the patient, which is supposed to be the reason for everything we do.

    .

    1. I agree – I think securing the airway in OHCA is probably not the most important of actions to be taken in the context of limited personnel resources. CPR, transport, and other medical interventions as indicated seem to be more likely to contribute to favorable survival.

      That said, the evidence supporting any one particular airway management strategy over another is weak and these opinions are subject to change!

      1. All opinions are subject to change, based on valid evidence.

        Our biggest problem appears to be assuming that we should continue to use “standards of care” without adequate evidence, because they were made “standards of care” when our standards were pathetically low.

        Our “standards of care”, which are not based on valid evidence of greater benefit than harm, should have expiration dates. If we do not come up with valid evidence that each “standard of care” is better than other treatments and better than no active treatment, that “standard of care is removed and can only be reinstated if valid evidence that it is better than other treatments and better than no active treatment.

        If nothing else, this would inspire these opponents of research to insist on studying their sacraments, rather than rally the gullible to shut down research as they did with the Jacobs study and attempted to with the Paramedic2 study.

        https://www.ncbi.nlm.nih.gov/pubmed/21745533

        https://www.bbc.com/news/uk-wales-north-east-wales-43516136

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  2. When are people like yourself going to stop doing this ? Picking one small element of a range of interventions and pretending that such commentary has meaning ?
    If our systems cannot get CPR started and a defibrillator on the patient within four minutes, the rest is largely moot as we do not yet possess the technology to resuscitate severely damaged end organ tissue with any degree of reliability or regularity.
    I have been hearing this type of specious nonsenses debated backwards and forwards for thirty years, I think of it as fiddling while Rome burns. Most systems in this country cannot improve things with any one particular intervention or similarly the withholding of one.
    As an example, I have seen this particular argument put forward so EMS systems can avoid deploying CPR devices, despite the improved CPR effectiveness during transport and movement, the reduced cognitive and physical load on the providers and MOST significantly the improved end organ perfusion they provide. Improved in ways that is evidenced by the emergence of Systems now needing to have ‘sedation during cpr’ guidelines to manage the immediate results of the improved perfusion – All put aside as survival to discharge is not significantly improved by such devices, according to those recalcitrant people.
    The solutions we are seeking are multifactorial, any argument that wishes to limit options in the field based on such untidy, non-homogenous data especially where the differences are so small and poorly reflected, is simply specious and wasteful of people’s time and resources and is advanced, I think without recognition of the weightier matters at hand.

    1. Unclear precisely what is meant by “When are people like yourself going to stop doing this”.

      These are publications in JAMA. Prehospital care is, as you say, tremendously muddy, with many other confounding interventions and devices. Regardless, systems of care making significant investments in training and technology based on the outcomes of these studies – and while I certainly agree, when you whittle it down, response time, defibrillation, and CPR matter vastly more, this airway debate continues.

    2. “I have seen this particular argument put forward so EMS systems can avoid deploying CPR devices, despite the improved CPR effectiveness during transport and movement,”

      We do not have any good reason to be transporting dead people, so you are advocating a treatment that is not needed.

      “now needing to have ‘sedation during cpr’ guidelines to manage the immediate results of the improved perfusion”

      The same is true for high quality CPR by humans.

      “All put aside as survival to discharge is not significantly improved by such devices, according to those recalcitrant people.”

      First, survival to discharge with good brain function is the thing that matters to patients.

      Those of us not doing this for patients, should be forced out of medicine before they do more harm. There is no reason to believe they are not causing harm.

      You use the word “recalcitrant”, which is defined as “having an obstinately uncooperative attitude toward authority or discipline” – as if these are problems with medicine. We have too many people going along and harming patients by just following orders.

      We need to eliminate the corruption of harming patients with the “standards of care”.

      We need to provide care that is best for patients, not for appearances.

      We need to stop harming patients with magical interventions that do not provide more benefit than harm.

      .

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