What is an advanced airway in patients at risk of respiratory failure or cardiac arrest?

What is an Advanced Airway?

An advanced airway is a device inserted beyond the oropharynx to secure the airway during cardiac arrest or respiratory failure, specifically including endotracheal tubes (ETT) and supraglottic airway devices (SGA), which allow for controlled ventilation without the need for continuous bag-mask seal. 1

Definition and Device Types

Advanced airways are distinguished from basic airway adjuncts (oropharyngeal and nasopharyngeal airways) by their ability to provide a more definitive airway management solution:

Endotracheal Intubation (ETT)

• Provides the most secure airway with best protection against aspiration by directly accessing the trachea below the vocal cords 2
• Requires direct visualization of the glottis, which typically necessitates interruption of chest compressions during cardiac arrest 1, 2
• Enables delivery of a selected tidal volume and provides an alternative route for drug administration 2
• Demands higher skill level and more frequent training to maintain competency 1

Supraglottic Airways (SGA)

• Include devices such as the laryngeal tube, i-gel, and esophageal-tracheal tube (Combitube) that sit above the glottis 1, 2
• Can be inserted without visualization of the vocal cords, making placement easier and faster 2, 3
• Can be successfully placed without interrupting chest compressions during CPR, a critical advantage over ETT 1, 3
• Provide some protection from aspiration compared to bag-mask ventilation, though not as complete as ETT 4
• Require less initial training and skill maintenance compared to endotracheal intubation 3

Clinical Application During Cardiac Arrest

Ventilation Strategy After Placement

Once an advanced airway is in place during cardiac arrest, the resuscitation approach fundamentally changes:

• Providers should give continuous chest compressions at 100-120 per minute without pauses for ventilation 1
• Ventilation is delivered asynchronously at 10 breaths per minute (1 breath every 6 seconds) 1, 2
• Excessive ventilation must be avoided as it compromises venous return, cardiac output, and cerebral blood flow 1

Confirmation of Proper Placement

• Continuous waveform capnography is the most reliable method for confirming and monitoring ETT placement (Class I, LOE A) 1
• Capnography should be used in the field, during transport, on hospital arrival, and after any patient transfer to detect tube misplacement or displacement 1
• For SGAs, effective ventilation should produce a capnograph waveform during CPR and after return of spontaneous circulation, though this has undergone limited evaluation 1
• Physical examination includes visualizing bilateral chest expansion and auscultating the epigastrium (no breath sounds) and lung fields bilaterally (equal breath sounds) 1

Current Evidence-Based Recommendations

Choice of Advanced Airway Strategy

The 2019 American Heart Association guidelines provide nuanced recommendations based on setting and provider expertise:

• Either bag-mask ventilation OR an advanced airway strategy may be considered during CPR (Class 2b, LOE B-R) 1
• In settings with low ETI success rates or minimal training opportunities, SGAs are preferred for out-of-hospital cardiac arrest (Class 2a, LOE B-R) 1, 3
• In settings with high ETI success rates or optimal training opportunities, either SGA or ETT can be used (Class 2a, LOE B-R) 1
• For in-hospital cardiac arrest by expert providers trained in these procedures, either SGA or ETT is acceptable (Class 2a, LOE B-R) 1

Critical Timing Considerations

• If advanced airway placement will interrupt chest compressions, providers may consider deferring insertion until the patient fails to respond to initial CPR and defibrillation attempts or demonstrates return of spontaneous circulation (Class IIb, LOE C) 1
• There is inadequate evidence to define the optimal timing of advanced airway placement relative to other interventions 1
• Recent research from the PART trial found no association between timing of advanced airway insertion attempt (whether laryngeal tube or ETI) and survival to hospital discharge 5

Common Pitfalls and Caveats

Provider Skill Requirements

• Frequent experience or frequent retraining is mandatory for providers who perform ETI (Class 1, LOE B-NR) 1
• EMS systems performing prehospital intubation must provide ongoing quality improvement programs to minimize complications and track overall placement success rates (Class 1, LOE C-EO) 1
• Unrecognized esophageal intubation is a catastrophic complication that dramatically increases aspiration risk and mortality 2, 3

Hospital-Level Variation

• Observational data from in-hospital cardiac arrest shows an inverse association between hospital rates of ETI use during CPR and survival to discharge, particularly in patients without pre-arrest respiratory failure 6
• This suggests that indiscriminate use of advanced airways, especially ETI, may be harmful when bag-mask ventilation would suffice 6

Physiological Risks

• Critical airway management itself can precipitate cardiac arrest in patients with preload-dependent cardiovascular systems through sedation, paralysis, and positive pressure ventilation effects 7
• All interventions that decrease preload (sedatives, paralytics, mechanical ventilation) can cause cardiovascular decompensation 7

Contraindications to Specific Devices

• Nasopharyngeal airways should be used with caution in severe craniofacial injury or suspected basilar skull fracture due to risk of intracranial placement 1
• In the presence of known or suspected basal skull fracture or severe coagulopathy, an oral airway is preferred over nasopharyngeal airway (Class IIa, LOE C) 1