Advanced airways and worse outcomes in cardiac arrest

January 20, 2013 by  
Filed under Acute Med, All Updates, EMS, Resus

A new study demonstrates an association between advanced prehospital airway management and worse clinical outcomes in patients with cardiac arrest. Done in Japan, the numbers of patients included are staggering: this nationwide population-based cohort study included 658 829 adult patients. They found that CPR with advanced airway management (use of tracheal tubes and even supraglottic airways) was a significant predictor of poor neurological outcome compared with conventional bag-valve-mask ventilation.

Association of Prehospital Advanced Airway Management With Neurologic Outcome and Survival in Patients With Out-of-Hospital Cardiac Arrest
JAMA 2013;309(3):257-66


Importance It is unclear whether advanced airway management such as endotracheal intubation or use of supraglottic airway devices in the prehospital setting improves outcomes following out-of-hospital cardiac arrest (OHCA) compared with conventional bag-valve-mask ventilation.

Objective To test the hypothesis that prehospital advanced airway management is associated with favorable outcome after adult OHCA.

Design, Setting, and Participants Prospective, nationwide, population-based study (All-Japan Utstein Registry) involving 649 654 consecutive adult patients in Japan who had an OHCA and in whom resuscitation was attempted by emergency responders with subsequent transport to medical institutions from January 2005 through December 2010.

Main Outcome Measures Favorable neurological outcome 1 month after an OHCA, defined as cerebral performance category 1 or 2.

Results Of the eligible 649 359 patients with OHCA, 367 837 (57%) underwent bag-valve-mask ventilation and 281 522 (43%) advanced airway management, including 41 972 (6%) with endotracheal intubation and 239 550 (37%) with use of supraglottic airways. In the full cohort, the advanced airway group incurred a lower rate of favorable neurological outcome compared with the bag-valve-mask group (1.1% vs 2.9%; odds ratio [OR], 0.38; 95% CI, 0.36-0.39). In multivariable logistic regression, advanced airway management had an OR for favorable neurological outcome of 0.38 (95% CI, 0.37-0.40) after adjusting for age, sex, etiology of arrest, first documented rhythm, witnessed status, type of bystander cardiopulmonary resuscitation, use of public access automated external defibrillator, epinephrine administration, and time intervals. Similarly, the odds of neurologically favorable survival were significantly lower both for endotracheal intubation (adjusted OR, 0.41; 95% CI, 0.37-0.45) and for supraglottic airways (adjusted OR, 0.38; 95% CI, 0.36-0.40). In a propensity score–matched cohort (357 228 patients), the adjusted odds of neurologically favorable survival were significantly lower both for endotracheal intubation (adjusted OR, 0.45; 95% CI, 0.37-0.55) and for use of supraglottic airways (adjusted OR, 0.36; 95% CI, 0.33-0.39). Both endotracheal intubation and use of supraglottic airways were similarly associated with decreased odds of neurologically favorable survival.

Conclusion and Relevance Among adult patients with OHCA, any type of advanced airway management was independently associated with decreased odds of neurologically favorable survival compared with conventional bag-valve-mask ventilation.

Comments

3 Responses to “Advanced airways and worse outcomes in cardiac arrest”

  1. Christian Winship on January 21st, 2013 19:29

    Is it that the actually advanced airway is harmful to patients or is it the fact that the advanced airway detracts from the optimal performance of CPR that reduces the odds of a positive outcome?

  2. Per P. Bredmose_VIKING ONE on January 23rd, 2013 08:17

    These numbers are fascinating……
    First the size of the study population – more than 600.000 patients included !
    Next – You are deemed proffficient in intubating after 30 intubations in theatre…
    In my work, both in the ED, in theatre as aneasthetist and in prehospital care, I have trained a lot of paramedics and technicians in intubating… only because I have been told that I have to… I to be frankly honest, it does take MUCH MORE that 30 intubations before one can do that prehosp in an effective SMOOTH, FAST, RELIABLE way without interrupting chestcompressions. I, my self can struggle with that… with several thousand intubations behind my… S how can anoone serious believe that 30 intubations is enough…
    Furthermore – apparently the Japanese team consist of 3 people, of whon ONE, and only ONE can CANNULATE, INTUBATE and DEFIBBRILATE…. which means that this persons is doing the most…..
    SO what does this study actually tell us… NOT MUCH…
    I dont see how the authors can make a conclusion on Advanced airinterventions and outcome….

    This, again, shows us that this debate has little to do with the intervention – but it is about WHO does it – and especially HOW THE INTERVENTION IS DONE that matters…..

    What a piece of SH…..T……..

  3. Cliff on January 24th, 2013 05:07

    This comment is from my friend Matthew MacPartlin, the Rollcage Medic:

    Really interesting study. HUGE dataset!!

    My first query was whether there was a survival bias that would make BVM appear superior, but there doesn’t appear to be. In fact, it looks like the data would tend to bias Advanced airway management. Ad given that EGAs contribute the vast majority of Advanced airway population, things look bad for the EGAs. (Resuscitation of arresting pigs anyone?)

    The next query was baseline characteristic difference and indeed there are some interesting ones. People treated with BVM-only were more likely to have had a heath care practicioner as their bystander, rather than a lay rescuer. They were also more likely to have had no bystander intervention at all and to have had a secondary contributer to their cardiac arrest, both of which one would imagine should lead to a worse outcome; yet they seem to have done better.

    Additionally, the BVM-only group were less likely to have had an EMT in the ambulance with them and waaaaay less likely to have had an IV canula placed and adrenalin (epinephrine) given, prompting consideration of delays to transport and again questioning the role of adrenalin in cardiac arrest.

    There may be other confounders embedded within the paper that more clever people than I can spot, but it makes me think a bit more about nonchalantly sinking an EGA. I also wonder about the apparent ease of placing an EGA but the potential for unrecognised misplacement leading to complications such as a folded EGA tip causing problems. Who was placing these devices and with what training? This recent review of available EGAs contains some insights into their use and is worth a read: Review Article: Evolution of the Extraglottic Airway: A Review of Its History, Applications, and Practical Tips for Success. Anesth Analg February 2012 114:349-368 (For some reason WordPress won’t let me paste the link to the free full text article, so you’ll have to Google it)
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