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For many years airway management received emphasis in cardiac arrest care, and ALS rescuers placed high priority on endotracheal intubation of cardiac arrest patients. However, the results of several studies question the wisdom of intubation during out‐of‐hospital cardiac arrest resuscitation. Some of the adverse events noted were tube misplacement, tube dislodgement, multiple laryngoscopy efforts, and failed intubation efforts [34–37]. Inadvertent hyperventilation often occurs after intubation, raising intrathoracic pressure and compromising CPP [38]. Perhaps most important is the frequent and often prolonged interruption of chest compressions [39].

The application of these findings to EMS practice presents important challenges. Although bag‐valve‐mask ventilation is theoretically adequate for resuscitation, the technique is difficult to execute in the prehospital setting where EMS clinicians may need to deliver ventilations with the patient situated on the floor, in the back of a moving ambulance, or on a moving stretcher [40]. Many EMS agencies still perform intubation for cardiac arrest but try to limit the number and duration of attempts [37]. Capnography should be used to verify endotracheal tube placement [41]. Although dependent on the quality of chest compressions, capnography waveforms in low‐flow states are still useful for ensuring endotracheal tube position.

The use of supraglottic airways such as the King LT^® and iGel^® for airway management in cardiac arrest is becoming more widely adopted. These devices are inserted blindly in the airway without the need for direct laryngoscopy and can typically be placed very quickly without pausing compressions (see Chapter 3). Several EMS agencies have chosen this method for the initial approach, reasoning that they cannot perform traditional intubation without compromising chest compressions. Others may make an initial attempt at intubation and if unsuccessful turn to a supraglottic device [42]. A subanalysis of the ROC PRIMED trial demonstrated a higher rate of survival with good functional status in patients receiving endotracheal intubation rather than supraglottic airway placement (OR 1.40; 95% CI 1.04, 1.89) during the resuscitation [42]. The AIRWAYS trial compared endotracheal intubation with the iGel supraglottic airway. There was no difference in survival or favorable neurologic outcome [43]. A second randomized trial comparing the King LT with endotracheal intubation demonstrated higher survival and higher survival with good neurologic outcome in the King LT group [44]. It is important to note that in the latter trial, intubation success was low (52%). Based on these findings, EMS agencies with high intubation success rates may favor endotracheal intubation for airway management while agencies with low intubation success rates (or infrequent intubation attempts) should favor supraglottic airway use.