Basic Sciences - Anatomy of Airway

Question 1

Formal name for ‘pillars of the fauces’ in mouth

Answer 1

Palatoglossal arch (anterior)
Palatopharyngeal arch (posterior)

Question 2

Functions of nasal passage / nasopharynx

Answer 2

Warm air
Humidify air
Filter inspired air
Olfaction
Speech resonation

Question 3

Nasal cavity epithelium

Answer 3

Pseudostratified ciliated columnar epithelium
(respiratory mucosa)

Question 4

Bones which form the hard palate

Answer 4

Palatine process of the maxilla
Horizontal part of the palatine bone

Question 5

Afferent nerve for gag reflex

Answer 5

Glossopharyngeal nerve

Question 6

Efferent nerve for gag reflex

Answer 6

Vagus nerve

Question 7

Components of the pharynx

Answer 7

Nasopharynx
Oropharynx
Laryngopharynx

Question 8

Lateral recesses either side of larynx

Answer 8

Piriform fossae

Question 9

Adenoids definition

Answer 9

Collection of lymphoid tissue on roof and posterior wall of pharynx

Question 10

Adenoids age group

Answer 10

Develop in early childhood
Regress at puberty

Question 11

Sensory supply to the tonsils

Answer 11

Branches of:
- Glossopharyngeal
- Maxillary
- Mandibular

Question 12

Tonsillar anaesthesia technique

Answer 12

Infiltration of analgesia into tonsillar bed is more effective than nerve blockade

Question 13

Swallowing reflexes to prevent aspiration

Answer 13

• Closure of the laryngeal sphincter
• Upward movement of the larynx behind the base of the tongue
• Reflex inhibition of breathing and channelling of liquid or food laterally by the epiglottis into the piriform fossae
• Epiglottis may also act as a ‘lid’ to the larynx to prevent substances entering the trachea

Question 14

Articulating cartilages forming larynx

Answer 14

Thyroid
Cricoid
Epiglottis

Question 15

Paired cartilages forming larynx

Answer 15

Arytenoid
Corniculate
Cuneiform

Question 16

Formal name for false vocal cords

Answer 16

Vestibular folds
Superior to true vocal cords

Question 17

Formal name for true vocal cords

Answer 17

Vocal folds
Inferior to false vocal cords

Question 18

Gap between vocal cords

Answer 18

Rima glottidis (aka ‘the glottis’)
Narrowest part of the airway

Question 19

Space above epiglottis where tip of laryngoscope is placed

Answer 19

Vallecula

Question 20

Name of posterior ‘nodules’ visible at posterior aspect of larynx

Answer 20

Arytenoid complex

Question 21

Muscle groups of the larynx

Answer 21

Extrinsic
Intrinsic

Question 22

Functions of extrinsic muscles of the larynx

Answer 22

Work with other muscles attached to the hyoid to move the larynx up and down during swallowing

Question 23

Functions of intrinsic muscles of larynx

Answer 23

Move vocal cords

Question 24

Diagram of intrinsic muscles of larynx

Answer 24

Question 25

Function of posterior cricoarytenoids muscles

Answer 25

Abduct vocal cords on inspiration Pulls posterior ends of arytenoid cartilages together medially to achieve abduction

Question 26

Function of lateral cricoarytenoids muscles

Answer 26

Adduct vocal cords to close them

Question 27

Function of aryepiglottics and thyroepilottics muscles

Answer 27

Laryngeal sphincters Close the laryngeal inlet during swallowing

Question 28

Function of cricothyroid muscles

Answer 28

Tensors of the cords Act by tilting the cricoid cartilage on the thyroid cartilage

Question 29

Function of the thyroarytenoids muscles and vocalis muscles

Answer 29

Relax the vocal cords Vocalis muscle responsible for fine adjustment of the cords

Question 30

Nerve supply to the larynx

Answer 30

Question 31

Sensory supply to larynx

Answer 31

Superior laryngeal nerve - internal laryngeal nerve branch superior to vocal cords Recurrent laryngeal nerve inferior to vocal cords

Question 32

Motor supply to larynx

Answer 32

Superior laryngeal nerve - external laryngeal branch supply to cricothyroid muscle Recurrent laryngeal nerve to all intrinsic muscles of larynx except cricothyroid muscle

Question 33

Path of right recurrent laryngeal nerve

Answer 33

Passes under right subclavian artery to ascend to larynx

Question 34

Path of the left recurrent laryngeal nerve

Answer 34

Passes under the aortic arch to ascend to the larynx

Question 35

Symptoms of damage to superior laryngeal nerve damage

Answer 35

Temporary hoarse voice due to loss of cricothyroid muscle function - muscle on other side compensates Increased aspiration risk due to loss of sensation above cords

Question 36

Symptoms of Unilateral recurrent laryngeal nerve damage

Answer 36

Hoarse voice with potential partial compensation from other side Glottis cannot close tightly so cannot generate positive intrathoracic pressure to cough effectively Aspiration risk - loss of infraglottic sensation

Question 37

Symptoms of Bilateral recurrent laryngeal nerve damage

Answer 37

Bilateral vocal cord palsy Severe respiratory distress Stridor as flaccid vocal cords flap together

Question 38

Management of Bilateral recurrent laryngeal nerve palsy

Answer 38

Urgent intubation acutely Tracheostomy likely to follow

Question 39

Why cricothyroidotomy should only be used as temporary airway

Answer 39

Vocal cords in close proximity and may be damaged Risk of subglottic stenosis

Question 40

Approximate vertebral level of larynx

Answer 40

C4-C6 Cricoid cartilage ~ C6