Airway Block

Question 1

What nerve provides sensation to the larynx below

the vocal cords?

Answer 1

The recurrent laryngeal nerve provides sensation to the larynx
below the vocal cords.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 310.

Question 2

What nerve provides sensory innervation to the

airway between the epiglottis and the vocal cords?

Answer 2

The airway between the epiglottis and the vocal cords derives
sensory innervation from the internal branch of the superior
laryngeal nerve.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 310.

Question 3

What nerves provide sensation to the mucous

membranes of the nose?

Answer 3

The mucous membranes of the nose are innervated by the
opthalmic division of the trigeminal nerve (V1) anteriorly and the
maxillary division of the trigeminal nerve (V2) posteriorly.
These nerves are also known as the anterior ethmoidal and
sphenopalatine nerves respectively.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 311.

Question 4

What is the only laryngeal muscle that does not
receive its motor innervation from the recurrent
laryngeal nerve?

Answer 4

The cricothyroid muscle, which is innervated by the external
laryngeal nerve.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 310.

Question 5

How is a glossopharyngeal block performed?

Answer 5

The glossopharyngeal block is performed by having the patient
open their mouth, then using a 25-gauge needle to inject 2 mL
of local anesthetic bilaterally at the base of the palatoglossal
arch (also called the anterior tonsillar pillar). This blocks the
lingual and some of the pharyngeal branches of the
glossopharyngeal nerve that provide sensation to the posterior
third of the tongue and oropharynx.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 1064-1065

Question 6

How is a transtracheal block performed?

Answer 6

A transtracheal block is performed by injecting 4 mL of 4%
lidocaine through a needle penetrating the cricothyroid
membrane into the trachea. The needle is advanced until air is
aspirated. At the end of expiration, the lidocaine is injected.
This will usually precipitate a cough, which will spread the
anesthetic throughout the airway.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 338.

Question 7

How would you anesthetize the posterior 1/3 of the

tongue?

Answer 7

The posterior 1/3 of the tongue and tonsillar pillars can be
anesthetized by blocking the lingual and pharyngeal branches
of the glossopharyngeal nerve with 2 mL of local anesthetic at
the base of the palatoglossal arch.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 1064-1065.

Question 8

How would you anesthetize the superior laryngeal

nerve?

Answer 8

Injection of 3 mL at the cornu on either side of the hyoid bone
anesthetizes the superior laryngeal nerve, which supplies
sensation to the airway below the epiglottis.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 338-339.