Airway Nerve Innervation

Question 1

what nerve is the nasal cavity innervated by?

Answer 1

trigeminal (5)

Question 2

anterior parts of nasal cavity and septum innervation

Answer 2

opthalmic –> anterior ethmoidal nerve

Question 3

remaining portion of nasal cavity/septum

Answer 3

maxillary nerve

Question 4

three prominent branches of maxillary nerve

Answer 4

lateral posterior superior
inferior posterior
nasopalatine

VIA SPHENOPALATINE GANGLION

Question 5

what does the sphenopalatine ganglion carry

Answer 5

1. sensory fibers of maxillary nerve
2. symp. fibers from carotid plexus
3. petrosal nerve (including glossopharyngeal nerve)
4. pharyngeal & palatine branches

Question 6

Pharynx innervation

Answer 6

glossopharyngeal

Question 7

Glossopharyngeal innervation

Answer 7

posterior 1/3 tongue
fauces & tonsillae
epiglottis
pharynx sensory
posterior 1/2 & soft palate taste
mucous glands
carotid sinus

Question 8

Sympathetic fibers derivation

Answer 8

carotid plexus & cervical sympathetic trunk

Question 9

Efferent motor fibers of pharynx -

Answer 9

innervate stylopharyngeus and join pharyngeal plexus

Question 10

where does the glossopharyngeal nerve emerge

Answer 10

jugular foramen and curves forward between jugular vein and ICA

Question 11

Motor innervation pharynx

Answer 11

vagus nerve

Question 12

Larynx innervation

Answer 12

SLN slants forward to cornu major of the hyoid bone

Question 13

SLN internal

Answer 13

enters through foramen in thyrohyoid membrane

-visceral sensory and secretomotor innervation to larynx above cords

Question 14

SLN external

Answer 14

descends along outside of thyrohyoid membrane beneath sternothyroid muscle to cricothyroid muscle (motors)

Question 15

Vagus nerve track extrathoracic

Answer 15

descends in carotid sheath to thoracic inlet

first: lies behind IJV and ICA
later: between IJV and ICA

Question 16

vagus nerve track intrathoracic

Answer 16

RLN
R - subclavian - up
L - aorta - up

ascends in a groove formed by the trachea and esophagus to the larynx

join cervical sympathetic chain - passing under the lower border of the inferior constrictor of the pharynx - it enters the larynx

Question 17

gag reflex

Answer 17

mechanical/chemical stimulation of areas innervated by glossopharyngeal area

efferent motor arc provided by vagus nerve

Question 18

how to block gag reflex

Answer 18

bilateral glossopharyngeal nerve block to eliminate the afferent arc of the gag reflex

Question 19

glottic closure reflex

Answer 19

selective stimulation of SLN

efferent arc encompasses superior as well as RLN

Question 20

glottic clossure exaggeration reflex

Answer 20

laryngospasm

via SLN stimulation

Question 21

cough receptors in larynx and trachea

Answer 21

afferent and efferent fibers via vagus nerve

Question 22

abolish cough reflex

Answer 22

topical anesthesia of subglottic larynx and trachea