Airway management is a core component of effective patient care in the pre-hospital setting. All patients, regardless of their emergency, require a structured airway assessment during their initial evaluation.

Essentials

1. Oxygenation and ventilation are the ultimate goals of airway management. Effective oxygenation depends on the fraction of inspired oxygen (FiO2), the capacity for gas to diffuse across the alveolar membrane, the ability (and availability) of hemoglobin to transport oxygen through the body, and the propensity of oxygen to diffuse into tissues. Effective ventilation depends on sufficient tidal volume and respiratory rate.
2. The effectiveness of airway management is measured by a variety of clinical endpoints. Oxygenation is most readily measured by SPO2. Ventilation is quantitatively measured by EtCO2. Chest rise, breath sounds, and consciousness are all important clinical assessments of effective ventilation.
3. A thorough assessment and reassessment of the respiratory system should be undertaken with all patients. Airway patency and respiratory mechanics should be continuously reconsidered and documented. Ominous airway sounds include stridor, snoring, stertorous, or wet characteristics.
4. Airway interventions progress from minimally to maximally invasive. The simplest and safest form of respiration is spontaneous ventilation by the patient themselves. With each necessary tier of airway intervention, there are progressively more harmful effects of intervention (such as the effects of positive pressure ventilation on the cardiopulmonary system and medications used for induction).
5. Field intubations are high risk invasive procedures. Although they may be clinically necessary, the goals of airway management should be attained by less invasive means whenever possible.

General Information

• Functional airway obstruction is the displacement of the airway anatomy into the passageway due to loss of airway tone, secondary to impaired consciousness from various means.

• Jaw thrust is the most effective manual maneuver to open an airway when airway muscle tone is lost. The jaw thrust moves the tongue and epiglottis away from the posterior oropharynx, maximizing space for air passage.

• Jaw thrust and head-tilt chin-lift are not mutually exclusive maneuvers. In the absence of cervical spinal injury, the two maneuvers should occur in tandem to maximize airway patency.

• The oropharyngeal airway (OPA) and nasopharyngeal airway (NPA) are equally effective at creating an air passage and should be used in conjunction with manual maneuvers where appropriate. Ease and speed of OPA insertion is advantageous, whereas the ability of the NPA to bypass the gag reflex may be more appropriate depending on circumstances.

• Bag-valve mask (BVM) ventilation is a difficult skill that requires positive feedback (chest rise) to determine efficacy with the chest appropriately exposed. Optimal BVM ventilation is performed by two providers. Only a slight (but definite) amount of chest rise is necessary to achieve safe ventilation.

• Application of a nasal cannula at 10-15L/min from a second oxygen source may be appropriate underneath a BVM to increase available FiO2 in critically ill hypoxic patients (referred to as high-flow nasal cannula, or NO DESAT)

• Positive end-expiratory pressure (PEEP) valves enhance alveolar recruitment and are an effective means of improving oxygenation. The application of PEEP is generally safe at low levels (starting at 5cmH2O) but can be harmful at any level, particularly in patients experiencing shock physiology and those experiencing dynamic hyperinflation.

• Paramedics should have a low threshold to apply a PEEP valve in the management hypoxic patients.

• Continuous positive airway pressure (CPAP) is not a means of airway management. In dyspnea, CPAP is an effective means of recruiting alveoli and improving oxygenation. BCEHS utilizes fixed flow-dependent CPAP devices that pair oxygen flow rates to CPAP. This means that we may see a transient drop in SPO2 on the initiation of CPAP before alveoli are recruited, as we often deliver a lower FiO2 than we may have previously been providing via non-rebreather (NRB). Supplemental oxygen can be applied where appropriate.

• CPAP is not capable of providing forced ventilation and should not be used for patients who have questionable airway integrity or lack the ability to spontaneously trigger ventilation.

• Indications for intubation include:

  • Oxygenation and ventilation when unable to achieve with maximal supraglottic airway management.
  • Protection of airway patency when not adequately managed with suction and severely soiled by fluid
  • Rapid progression of airway compromise from inflammation due to burns or angioedema with prolonged transport time.

Interventions