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Awake intubation provides many
advantages over the anesthetic state:
 maintenance
of spontaneous ventilation in the event that the airway cannot be
secured rapidly,
increased
size and patency of the pharynx,
relative
forward placement of the base of the tongue,
posterior
placement of the larynx,
and
patency of the retropalatal space.
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Contraindications to elective
awake intubation include:
patient
refusal,
inability
to cooperate (e.g., child, profound mental retardation, dementia,
intoxication),
allergy
to local anesthetics. |
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the patient must be
prepared
both physically and
psychologically |
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Most adult patients
will appreciate an explanation of the need for an awake airway
exam and will be more cooperative once they realize the
importance of any uncomfortable procedures.
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supply supplemental
O2 |
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Medication used to allay anxiety |
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sedatives
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producing
obstruction or apnea |
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overly sedated
patient may not be able to protect the airway from
regurgitated gastric contents, or cooperate with procedures.
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Small doses of benzodiazepines
(diazepam, midazolam, lorazapam) are commonly used to alleviate
anxiety without producing significant respiratory depression.
Opioid receptor agonists (e.g.,
fentanyl, alfentanil, remifentanil) can also be used in small,
titrated doses for their sedative and antitussive effects, although
caution must be exercised.
Administration of antisialagogues
is important to the success of awake intubation techniques.
Clearing of airway secretions is
essential to the use of indirect optical instruments (e.g.,
fiberoptic bronchoscope, rigid fiberoptic laryngoscope) because
small amounts of any liquid can obscure the objective lens.
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atropine (0.5–1 mg im or iv)
glycopyrrolate
(0.2–0.4 mg, im or
iv)
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other significant effects |
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by reducing
saliva production, these drugs increase the effectiveness of
topically applied local anesthetics by removing a barrier to
mucosal contact and reducing drug dilution. |
Vasoconstriction of the nasal
passages: is needed for fiberoptic-aided intubation.
Risk for gastric regurgitation and
aspiration: prophylactic measures should be undertaken.
Local anesthetics
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areas to local anesthetic therapy |
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the nasal cavity / nasopharynx, the pharynx
base of tongue
the
larynx / trachea. |
Lidocaine, topically applied, peak onset is within 15 minutes.
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Lidocaine
preparations |
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injectable / topical solution |
1%, 2% 4% |
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viscous solution |
1%, 2% |
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ointment |
1%, 5% |
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aerosol |
10% |
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Tips for Success |
Patient cooperation enhanced by adequate explanation and
preparation
Control secretions (use of antisialogogue)
Give adequate sedation to alleviate anxiety
Give adequate anesthesia to ensure patient comfort
To Avoid Complications:
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Measure/calculate all drugs
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Suction excess volume of oral spray
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Cautious application of L.A. in patients with sepsis or
traumatized mucosa
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Monitor carefully
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Provide supplemental Oxygen
Signs & Symptoms of L.A. Toxicity:
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Seizures
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CV collapse
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Methemoglobinemia
N.B. = nerve
block; L.A. = local anesthesia; RR = Respiratory Rate;
S.E. = Side
Effects
Local
Anesthesia & Sedation for Airway Management in the Awake
Patient
Developed from:
Osborn I,
Gooden C, Follmer J, Perez A. A Taste of Anesthesia:
Improving Airway Topicalization (Brochure),
Department of Anesthesiology, Mount Sinai School of
Medicine, Bronx, NY, 2006. |
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