Airway Management Research Update
A recent quarterly update on airway management research from Airway World discussed four new studies concerning the management of patient airways in the prehospital and in-hospital settings.
During the hour-long March 18 webinar, Calvin A. Brown III, MD, discussed a study from the December 2014 edition of Annals of Emergency Medicine, “Apneic Oxygenation Was Associated With Decreased Desaturation Rates During Rapid Sequence Intubation by an Australian Helicopter Emergency Medicine Service.” In this retrospective study, the Greater Sydney Area Helicopter Emergency Medical Service looked at prospectively collected airway registry data. A total of 728 patients who underwent rapid sequence intubation (RSI) between September 2009 and July 2013 were examined, with 310 of those patients receiving RSI prior to the introduction of apneic oxygenation and 418 receiving RSI after its introduction. Patients were evaluated to see if there was an association between the introduction of apneic oxygenation and incidences of desaturation.
What researchers found was the introduction of apneic oxygenation was followed by a decrease in desaturation rates from 22.6% to 16.5%—a difference of 6.1%. Brown said this indicates apneic oxygenation should be used for predicted rapid desaturations in the prehospital setting.
A second study, published in the November 2014 edition of the British Journal of Anaesthesia, looked at intubating obese patients. “Difficult intubation in obese patients: incidence, risk factors, and complications in the operating theatre and in intensive care units” studied the complication rate of intubating obese patients in France and noted difficult intubations were twice as common in the ICU as they were in the OR (16.3%–8.2%) and severe complications were 20 times more common in the ICU (41%–2%). Brown said what providers can learn from this is obese patients present unique complications for intubation, but those can be dealt with via robust pre-oxygenation, lean body weight induction agent dosing, and early and frequent use of airway adjuncts in the event the first attempt at intubation fails.
From December 2014’s Annals of Emergency Medicine comes another study, “Techniques, Success, and Adverse Events of Emergency Department Adult Intubations,” which looked at 17,583 adult intubations in the emergency department from 13 centers across a decade, from 2002–2012. What researchers found were trends in emergency intubation from this period changed significantly. Emergency intubations had a high success rate, which was only increasing over time as providers adopted video laryngoscopy. Additionally, etomidate was still the induction agent of choice, but both ketamine and propofol were increasing in use, which Brown noted had a lot to do with shortages of etomidate beginning around 2010.
Finally, a study just published in the March 2015 edition of the Journal of Emergency Medicine, “The C-MAC® Video Laryngoscope Is Superior to the Direct Laryngoscope for the Rescue of Failed First-Attempt Intubations in the Emergency Department,” compared the effectiveness of the C-MAC video laryngoscope to the direct laryngoscope (DL) when used to rescue a failed first attempt intubation in the emergency department. During the five-year study period, there were 460 adult orotracheal intubation attempts by emergency physicians that were not successful on the first attempt. In 398 (86.5%) of these cases the same operator performed the second attempt. The C-MAC was utilized for the second attempt in 141 cases and was successful in 116 (82.3%) and the DL was utilized in 94 cases and was successful in 58 (61.7%). Researchers concluded that after a failed first intubation attempt in the ED, regardless of the initial device used, the C-MAC was more successful than the DL when used for the second attempt, suggesting that the CMAC is the preferred rescue device after an initial intubation attempt in the ED fails.
Brown took this a step further and said what this really points to is providers should start intubations with a video laryngoscope rather than a direct laryngoscope. If you do start with a Dl and fail, switch to a VL, Brown added. And if you start with the VL and fail, try again with the VL and don’t switch back to a DL.
The next Airway World quarterly airway management research update will be held June 26, from 2–3 p.m. EST.
