medwireNews: Research in JAMA adds to suspicions that advanced airway management techniques may do more harm than good in patients with out-of-hospital cardiac arrest.
The study, which involved 649,359 patients from the All-Japan Utstein Registry, found any type of advanced airway management to be associated with a reduced chance for neurologically favorable survival, defined as a cerebral performance category of 1 or 2.
In a related editorial, Henry Wang (University of Alabama School of Medicine, Birmingham, USA) and Donald Yealy (University of Pittsburgh, Pennsylvania, USA) say that the observational study is subject to a number of weakness, most notably confounding by indication if advanced airway management is simply a marker for other predictors of poor outcome.
But they stress that rigorous trials are now essential, although they may prove problematic. "Much like intravenous epinephrine for treating cardiac arrest, endotracheal intubation has high perceived value among health care personnel involved in resuscitation," they comment. "Convincing practitioners to alter these beliefs is a challenge."
To minimize confounding by indication, the researchers, led by Kohei Hasegawa (Massachusetts General Hospital and Harvard Medical School, Boston, USA), used a propensity score representing the likelihood for patients receiving advanced airway management.
Among 357,228 patients with propensity-score matching, endotracheal intubation was associated with a 55% reduction in the odds for a neurologically favorable outcome and use of supraglottic airways with a 64% reduction, relative to bag-valve-mask ventilation.
In the whole cohort, 6% of patients underwent endotracheal intubation and 37% were ventilated with a supraglottic airway. Favorable neurologic outcome occurred in 1.0% and 1.1% of patients who were ventilated with endotracheal intubation and supraglottic airways, respectively, compared with 2.9% of those given bag-valve-mask ventilation, and the difference persisted after accounting for multiple confounders, including bystander cardiopulmonary resuscitation.
Although advanced airway management may be favored by some paramedics, both the study authors and the editorialists stress that emergency medical personnel struggle to achieve and maintain expertise in the techniques because of the rare opportunities to learn and practice in emergency situations. This may increase the risk for adverse effects such as unrecognized esophageal intubation, tube dislodgement, iatrogenic hypoxemia, and bradycardia.
Also, use of advanced airway techniques may disrupt the delivery of basic life support.
"Emergency medical services professionals across the world must engage in the scientific process," say Wang and Yealy.
They stress: "Absent this investment, the emergency medical services community risks turning a blind eye and embracing ineffective or harmful airway interventions."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013