Advanced Trauma Life Support ATLS Student Course Manual 2018

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CHAPTER 2 n Airway and Ventilatory Management
have associated cribriform plate fractures, and the
insertion of any tube through the nose can result in
passage into the cranial vault.
A patient wearing a helmet who requires airway
management must have his or her head and neck held
in a neutral position while the helmet is remo-ved
(n FIGURE 2-3; also see Helmet Removal video on MyATLS
mobile app). This is a two-person procedure: One person
restricts cervical spinal motion from below while the
second person expands the sides of the helmet and
removes it from above. Then, clinicians reestablish
cervical spinal motion restriction from above and
secure the patient’s head and neck during airway
management. Using a cast cutter to remove the helmet
while stabilizing the head and neck can minimize
c-spine motion in patients with known c-spine injury.
Predicting Difficult Airway
Management
Before attempting intubation, assess a patient’s airway
to predict the difficulty of the maneuver. Factors
that indicate potential difficulties with airway
maneuvers include:
••
C-spine injury
••
Severe arthritis of the c-spine
••
Significant maxillofacial or mandibular trauma
••
Limited mouth opening
••
Obesity
••
Anatomical variations (e.g., receding chin,
overbite, and a short, muscular neck)
••
Pediatric patients
When such difficulties are encountered, skilled
clinicians should assist.
The mnemonic LEMON is a helpful tool for assessing
the potential for a difficult intubation (n BOX 2-1; also see
LEMON Assessment on MyATLS mobile app). LEMON
has proved useful for preanesthetic evaluation, and
several of its components are particularly relevant
in trauma (e.g., c-spine injury and limited mouth
opening). Look for evidence of a difficult airway
(e.g., small mouth or jaw, large overbite, or facial
trauma). Any obvious airway obstruction presents an
immediate challenge, and the restriction of cervical
spinal motion is necessary in most patients following
blunt trauma, increases the difficulty of establishing
an airway. Rely on clinical judgment and experience
in determining whether to proceed immediately with
drug-assisted intubation.
Airway Decision Scheme
n FIGURE 2-4 provides a scheme for determining the
appropriate route of airway management. This
box 2-1 lemon assessment for difficult intubation
L = Look Externally: Look for characteristics that are known
to cause difficult intubation or ventilation (e.g., small mouth
or jaw, large overbite, or facial trauma).
E = Evaluate the 3-3-2 Rule: To allow for alignment of the
pharyngeal, laryngeal, and oral axes and therefore simple
intubation, observe the following relationships:
• The distance between the patient’s incisor teeth should
be at least 3 finger breadths (3)
• The distance between the hyoid bone and chin should be
at least 3 finger breadths (3)
• The distance between the thyroid notch and floor of the
mouth should be at least 2 finger breadths (2)
M = Mallampati: Ensure that the hypopharynx is adequately
visualized. This process has been done traditionally by
assessing the Mallampati classification. In supine patients,
the clinician can estimate Mallampati score by asking the
patient to open the mouth fully and protrude the tongue; a
laryngoscopy light is then shone into the hypopharynx from
above to assess the extent of hypopharynx that is visible.
O = Obstruction: Any condition that can cause obstruction of
the airway will make laryngoscopy and ventilation difficult.
N = Neck Mobility: This is a vital requirement for
successful intubation. In a patient with non-traumatic
injuries, clinicians can assess mobility easily by asking
the patient to place his or her chin on the chest and
then extend the neck so that he or she is looking toward
the ceiling. Patients who require cervical spinal motion
restriction obviously have no neck movement and are
therefore more difficult to intubate.
Continued
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