From a recent review:
Purpose of review
Cardiac arrest mortality remains high, and the impact on outcome of most advanced life support interventions is unclear. The optimal method for managing the airway during cardiac arrest remains unknown. This review will summarize and critique recently published evidence comparing basic airway management with the use of more advanced airway interventions [insertion of supraglottic airway (SGA) devices and tracheal intubation].
Systematic reviews generally document an association between advanced airway management and worse neurological outcome but they are subject to considerable bias. A recent observational study of tracheal intubation for in-hospital cardiac arrest that used time-dependent propensity matching showed an association between tracheal intubation during the first 15 min of cardiac arrest and a worse a neurological outcome compared with no intubation in the first 15 min. In a recent randomized clinical trial, tracheal intubation was compared with bag-mask ventilation (with intubation only after return of spontaneous circulation) in 2043 patients with out-of-hospital cardiac arrest. There was no difference in favorable neurological outcome at 28 days.
Most of the available evidence about airway management during cardiac arrest comes from observational studies. The best option for airway management is likely to be different for different rescuers, and at different time points of the resuscitation process. Thus, it is common for a single patient to receive multiple ‘stepwise’ airway interventions. The only reliable way to determine the optimal airway management strategy is to undertake properly designed, prospective, randomized trials. One randomized clinical trial has been published recently and two others have completed enrollment but have yet to be published.