The Airway Algorithm

Background: Airway management is a critical skill at music festivals (MFs) due to the presence of potential full stomachs and altered mental status (AMS). Although airway complications and aspiration are rarely reported as primary causes of death, they are likely contributors in the context of recreational drug toxicity as a secondary precipitant of respiratory and/or cardiac arrests. Specific guidance for airway management and mitigation of aspiration risk at MFs is limited; most evidence is based on the toxicology and anesthesia literature, with extrapolations from prehospital data, ED sedation and postanesthetic care experience.

Basic Airway: The evaluation of AB (Airway and Breathing) in the festival environment is challenging due to factors like loud music, lack of / strobing of lights, crowds and AMS. The Look Listen* and Feel approach (see Figure 1) can be tailored to this unique space. Basic airway skills are paramount. Often underrated in the hospital environment, they are likely one of the most effective diagnostic and pathway-defining tools; this AB process often occurs at a critical (and brief) window for intervention. Luckily, attendees by and large are young and healthy, with normal BMI, airway anatomy and cardiorespiratory physiology at baseline. The vast majority of intoxicated patients are still breathing spontaneously and need little beyond supportive monitoring. Application of a painful stimulus (trapezius squeeze or finger pressure behind the angle of the jaw) is great for initial evaluation of the AV*PU scale; it also provides potential resuscitation if either A or B are found to be abnormal. See Table 1 for interventions. Overall, experience shows that advanced interventions are needed only in a small minority of patients.

Aspiration: Aspiration is a major risk at MFs. Like pregnant women – the quintessential patients at risk of aspiration – intoxicated patients at MFs require adapted and reasoned care. True aspiration requires alignment of a “swiss cheese” series of events where stomach contents, regurgitation and loss of airway reflexes result in entry into the bronchial tree with clinically significant pneumonitis and/or loss of ventilatory volume. The combination of potential full stomachs, altered mental status (AMS) and our own therapeutic interventions means that the risk of this complication can be minimized through careful selection of interventions and avoidance of emetic stimuli. This is reflected by unpublished field experience where stimulation, recovery position and airway repositioning are used an order of magnitude more than airway adjuncts; furthermore the use of nasopharyngeal over oropharyngeal airways, the avoidance of gag reflex testing and bag valve mask / positive pressure ventilation entirely – and gentle low pressures when used at all – all aid in decreasing the risk. There is some suggestion that deep loss of consciousness is protective, with the middle range of Glasgow Coma Scales (GCS 5-13, especially while upward on emergence) being the most risky period.

Intubation: The decision to intubate is a risk/benefit evaluation that must be made for each individual patient. In general at MFs, less is more in people who are stable and spontaneously breathing recognizing that intubation has associated risks particularly in an out of hospital, austere or remote setting. In select patients, intubation is often not indicated or necessary despite GCS < 8 and provider apprehension. Evidence and experience is emerging in support for selective non-intubation and close continuous monitoring in select patients. Research has postulated the advantages to avoiding intubation in case series and emergency department practice.

Management: The focus is on (a) promptly identifying and correcting abnormalities of A&B, (b) treating and minimizing patient and provider risk factors for aspiration, and (c) identifying appropriate patients for close and continuous monitoring and observation. See Figure 1 for an algorithm outlining this approach.

Ensure to consider an approach for these key questions:

1. Is this patient making respiratory efforts?

2. Is this patient moving air?

3. Does this patient need basic interventions?

4. Is this patient likely to benefit from intubation?

The Recovery Position

References

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