Always consider the presence of concurrent cervical spine

injury in victims of trauma and immobilize as appropriate.

Carefully examine the face, noting any signs of significant

facial trauma and the presence of a beard, both of which

frequently impair adequate BVM ventilation. Inspect the

oropharynx, noting the presence of dentures; the size of

the teeth and presence of a significant overbite; visibility of

the soft palate, uvula, and tonsillar pillars (ie, Mallampati

classification); and the presence of significant airway swelling. The pooling of blood or secretions in the oropharynx

indicates an inability to properly protect the airway. A good

adage to remember when assessing the airway is the 3-3-2

rule. The inability to open the mouth 3 finger breaths, a

distance from the tip of the chin to the base of the neck less

than 3 finger breaths, or a distance between the mandibular floor and the prominence of the thyroid cartilage of less

than 2 finger breaths all predict more difficult ETT place ­

ment. Assess the range of motion of the cervical spine,

provided there is no concern for occult injury.

DIAGNOSTIC STUDIES

..... Laboratory

Although abnormalities on either blood gas analysis (hypercapnia) or pulse oximetry (hypoxemia) may be indicative of

an inadequate airway, normal values on either of these studies should not j ustify the delay of definitive intervention in

the appropriate clinical scenario. Progressive abnormalities

on serial testing (increasing PaC02

, decreasing Pa02

) in

patients who are clinically decompensating indicates the

need for airway intervention.

..... Imaging

Imaging studies should not be used to predict the need for

airway intervention. Obtain a chest x-ray (CXR) in all

patients after intubation to confirm proper ETT placement.

The tip of the ETT should be visualized approximately

2 em above the carina. Deeper insertion results in placement into the right mainstem bronchus.

MEDICAL DECISION MAKING

Consider all rapidly reversible causes of airway compromise

(eg, hypoglycemia, opioid overdose) before pursuing endotracheal intubation. Proper intervention may transform a

comatose patient with a rather tenuous airway into an awake

coherent individual with adequate airway protection.

Identify patients who are likely to present a difficult airway

and those who require specialized approaches ( eg, head

trauma precautions, hypotension, cervical spine injury) and

proceed accordingly (Figure 1 1-1).

PROCEDURES

..... Bag-Valve-Mask Ventilation

Proper BVM ventilation requires an open airway and an

airtight seal between the mask and the patient's face. Use

the head-tilt chin-lift technique (jaw-thrust maneuver in

trauma victims) to open the airway and insert oropharyngeal or nasal adjuncts as necessary to maintain patency.

Avoid the use of oral adjuncts in patients with intact gag

reflexes and nasal adjuncts in patients with significant

mid-face trauma. With proper technique and a high-flow

oxygen source, this method can provide an Fi02 of

approximately 90% ( Figure 1 1-2).

..... Rapid-Sequence Intubation

Preoxygenate all patients with a high-flow oxygen source

(eg, nonrebreather [NRB] mask) for several minutes as

time permits before RSI. Avoid positive pressure ventilation

(eg, BVM) to prevent insufflation of the stomach, which

can increase the patient's risk for aspiration. Use this time

to prepare and check your equipment. Ensure adequate N

access and proper function of the suction device. Remove