Airway Anatomy

Question 1

Muscles that tense the vocal cords?

elongates

Answer 1

Cricothyroid
(“cords tense”)

think of the cricothyroid as the tuning fork for the vocal cords :)

Question 2

Muscles that relax the vocal cords?

Answer 2

Thyroarytenoids

“They Relax”

Question 3

Muscles that ABduct the vocal cords?

Answer 3

Posterior Cricoarytenoid

“pull cords apart”

Question 4

Muscles that ADduct the vocal cords?

Answer 4

Lateral Cricoarytenoids

“let’s close airway”

Question 5

The superior laryngeal nerve branches off what nerve?

Answer 5

Vagus nerve

Question 6

The superior laryngeal nerve divides into what two branches?

Answer 6

internal and external branch of the SLN.

Question 7

The internal branch of the SLN penetrates what membrane?

Answer 7

The internal branch penetrates the thyrohyoid membrane.

Question 8

The external branch of the SLN enters which muscle?

Answer 8

The external branch enters the cricothyroid muscle.

Question 9

The RLN branches off of the vagus nerve inside of what structure?

Answer 9

inside the thorax

Question 10

What does the right RLN loop under and what does the L RNL loop under?

Answer 10

The right RLN loops under the subclavian artery.

The left RNL loops under the aortic arch.

Question 11

Which RLN is more susceptible to injury?

Answer 11

The left due to looping under the aortic arch.

Question 12

Which branch of the SLN innervates the cricothyroid muscle?

Answer 12

external branch (motor)

Question 13

Which nerve innervates the posterior side of the epiglottis to the top side of the vocal cords?

Answer 13

SLN internal branch

Question 14

Which nerve innervates the cricothyroid muscle?

Answer 14

SLN external branch

Question 15

4 nerves that innervate the sensory portion of the airway?

Answer 15

trigeminal
glossopharyngeal
SLN
RLN

Question 16

Injury to the trunk of the SLN or the external branch can cause what and why?

Answer 16

can cause hoarseness, because the vocal cords can not tense.

Question 17

Unilateral injury to the RLN results in what kind of paralysis? Does it cause Respiratory distress?

Answer 17

results in paralysis of the ipsilateral vocal cord abductors, this does not cause respiratory distress.

Question 18

Explain acute bilateral injury to the RLN and what must be done?

Answer 18

Results in bilateral paralysis of the vocal cord abductors. This allows for unopposed tensing action by the cricothyroid muscle. Therefore a patient with an acute injury to BOTH RLNs is at risk for stridor and respiratory distress.

Patient requires intubation or surgical airway.

Question 19

Chronic injury to the RLN, tell me about it?

Answer 19

well tolerated and does not cause respiratory distress.

Question 20

What are some conditions that can cause Left side only RLN injury?

Answer 20

Aortic arch aneurysm
Thoracic tumor
Left atrial enlargement (mitral stenosis)
PDA ligation

Question 21

Glossopharyngeal Block, how to tell when you are too deep, when to redirect, how much LA is injected, and what are the risks?

Answer 21

aspiration of air = too deep

when you aspirate blood you should withdrawal and redirect medially.

1-2ml of LA on both sides injected

5% incidence of intracarotid injection with a risk of seizures

Question 22

Where do you inject for a glossopharyngeal block?

Answer 22

needle is inserted at the base of the palatoglossal arch (anterior tonsillar pillar) depth of 0.25-0.5 cm.

Question 23

Insertion direction of the needle during a transtracheal block?

Answer 23

needle is advanced in a caudal direction as it penetrates the cricothyroid membrane.

Question 24

During a transtracheal block what should the patient do before injection of LA, and what does this cause?

Answer 24

After aspiration and before injection the patient should take a deep breath, during the deep breath 3-5ml of LA is injected to the tracheal lumen this causes the patient to cough and sprays LA up through the cords.

Question 25

The adult larynx extends from what vertebrae to what vertebrae?

Answer 25

C3-C6

Question 26

name the three paired cartilages and the three unpaired cartilages

Answer 26

Paired are : corniculate arytenoid cuneiform unpaired are: Thyroid cricoid Epiglottis

Question 27

Can you see the arytenoids during direct laryngoscopy?

Answer 27

No

Question 28

What two diseases can significantly decrease the movement of the arytenoids and possibly cause airway obstruction?

Answer 28

rheumatoid arthritis and Lupus | the arytenoids create a ball and socket joint with the cricoid cartilage allowing the vocal cords to move and function

Question 29

What membrane is punctured during a cricothyroidotomy for emergent securement of the airway?

Answer 29

cricothyroid membrane | know the location for a hotspot question, below the thyroid and above the cricoid

Question 30

What is the largest cartilage in the larynx?

Answer 30

Thyroid

Question 31

What is the the only complete cartilaginous ring in the airway?

Answer 31

Cricoid

Question 32

What is the narrowest part of the pediatric airway? (controversial answer)

Answer 32

The answer will be either vocal cords or cricoid ring. In the anesthetized child the narrowest region is the vocal cords BUT they are soft and can be stretched by an ETT placed between them. The cricoid ring is fixed and can not be stretched or increased in diameter, it can however be reduced by edema that results from an ETT that is too large, multiple intubations, prolonged intubation etc. So hopefully both will not be listed on boards as an answer and if they are maybe the question will clue you in.

Question 33

Narrowest region in the adult airway?

Answer 33

vocal cords

Question 34

If a patient has a laryngospasm what outcomes may it result in?

Answer 34

``` complete airway obstruction negative pulmonary edema gastric aspiration cardiac arrest death ```

Question 35

Risk factors for laryngospasm previous to anesthesia?

Answer 35

active or recent upper airway infection (<2 weeks) exposure to 2nd hand smoke reactive airway disease GERD age less than 1 year

Question 36

Risk factor for laryngospasm in the OR?

Answer 36

light anesthesia concurrent with airway manipulation saliva or blood in the upper airway hyperventilation hypocapnia surgical procedures involving the airway

Question 37

Reflex pathway: what is the afferent limb?

Answer 37

SLN internal branch

Question 38

Reflex pathway: what is the efferent limb?

Answer 38

SLN external branch + recurrent laryngeal nerve

Question 39

ADDuction of the vocal cords is by?

Answer 39

lateral cricoarytenoid and thyroarytenoid

Question 40

Tensing of the vocal cords is by?

Answer 40

cricothyroid

Question 41

Signs of a laryngospasm?

Answer 41

inspiratory stridor suprasternal and supraclavicular retraction during inspiration "rocking horse" appearance of chest wall increased diaphragmatic excursion lower rib flailing

Question 42

factors that reduce the likelihood of laryngospasm?

Answer 42

avoidance of airway manipulation during light plane CPAP 5-10 during inhalation induction as well as immediate post extubation removal of pharyngeal secretions and blood before extubation. deep or awake extubation, not in between Laryngeal lidocaine (only last 30 min.) IV lidocaine before extubation hypercapnia/hypoventilation PaO2 < 50 mmHg

Question 43

What natural mechanism tends to break laryngospasm? (but you do not want to wait around for it)

Answer 43

hypercapnia and hypoxemia

Question 44

If a child is less than five years of age you should administer what with your succinylcholine and why?

Answer 44

atropine 0.02 mg/kg with succinylcholine to prevent bradycardia

Question 45

What is/how do you perform Larson's Maneuver?

Answer 45

It is not a simple jaw thrust. Larson's maneuver is application of firm pressure to the laryngospasm notch located just behind the earlobe. Pressure is applied bilaterally towards the skull base. pressure should be applied for 3-5 seconds then released for 5-10 seconds. Repeat until relief of laryngospasm

Question 46

What does Larson's maneuver accomplish?

Answer 46

1. displaces the mandible anteriorly to help open the airway. 2. it often breaks laryngospasm by causing the lightly anesthetized patient to sigh.

Question 47

What is the difference between Valsalva's maneuver and Muller's maneuver?

Answer 47

Valsalva is exhalation against a closed glottis Muller's is inhalation against a closed glottis The risk of Muller's is sub atmospheric pressure in the thorax that can cause negative pressure pulmonary edema

Question 48

During anesthesia relaxation of the Tensor Palatine muscle will most likely cause airway obstruction at which level?

Answer 48

soft palate

Question 49

During anesthesia relaxation of the Genioglossus muscle will most likely cause airway obstruction at which level?

Answer 49

Tongue

Question 50

During anesthesia relaxation of the hyoid muscle will most likely cause airway obstruction at which level?

Answer 50

Epiglottis

Question 51

Where does the lower airway begin and end?

Answer 51

Begins at the trachea and ends at the alveoli.

Question 52

The trachea begins at what vertebrae and ends at what vertebrae?

Answer 52

begins at C6 and ends at T4-5

Question 53

Sensory innervation of the trachea is by what nerve?

Answer 53

Vagus

Question 54

The carina is at located at what vertebrae?

Answer 54

T4-5

Question 55

The R mainstem bronchi has an angel of?

Answer 55

25 degrees

Question 56

The L mainstem bronchi has an angle of?

Answer 56

45 degrees

Question 57

How long is the R mainstem bronchi and the L mainstem bronchi?

Answer 57

R is 2.5 cm long | L is 5 cm long

Question 58

Which type of cells in the lungs produce surfactant?

Answer 58

Type II cells

Question 59

Which type of cells in the lungs provide surface for gas exchange?

Answer 59

Type I cells

Question 60

Which type of cells in the lungs can produce another type of cells in the lungs?

Answer 60

type II cells can produce type I cells

Question 61

Which cell type in the lungs is resistant to oxygen toxicity and capable of cell division?

Answer 61

Type II cells

Question 62

Which cell type in the lungs are macrophages?

Answer 62

Type III cells

Question 63

Which cell type in the lungs cover 80% of alveolar surface and form tight junctions?

Answer 63

Type I cells

Question 64

Which cell type in the lungs fights infection and produces inflammatory response?

Answer 64

Type III cells

Question 65

True or False | Neutrophils are present in all normal lungs alveoli?

Answer 65

False, neutrophils are present in the alveoli in smokers and patients with acute lung injury.

Question 66

What is the distance between the incisors and the larynx and then the distance from the larynx to the carina?

Answer 66

13 cm and 13cm for a total of 26 cm (variability can exist)

Question 67

What is different about the take off degree of the mainstem bronchi in children up to 3 years of age?

Answer 67

both bronchi take off at 55 degrees

Question 68

Does airflow velocity speed up or slow down as you move down the tracheobronchial tree?

Answer 68

slows down This is because at each division the diameter of the the new branches become smaller, however the total cross sectional area of all the airways in the division increases.

Question 69

What two things does the trachea contain that the terminal bronchioles do not have?

Answer 69

``` C shaped rings goblet cells (mucus secretion) ```

Question 70

The anterior tongue (2/3) is innervated by which nerve?

Answer 70

Trigeminal nerve

Question 71

The vallecula is innervated by which nerve?

Answer 71

Glossopharyngeal

Question 72

The Trachea is innervated by which nerve?

Answer 72

RLN

Question 73

The posterior epiglottis is innervated by which nerve?

Answer 73

SLN

Question 74

What three nerve blocks provide anesthesia for oral fiberoptic intubation?

Answer 74

glossopharyngeal, superior laryngeal, and recurrent laryngeal blocks.

Question 75

What block would you perform for a patient to tolerate a scope in the oropharynx?

Answer 75

glossopharyngeal block which is 1-2ml of LA at the tonsillar pillars bilaterally.

Question 76

If a patient can not tolerate a scope for awake intubation just beyond the epiglottis but before the vocal cords then what regional technique will increase the patients ability to tolerate the rest of the procedure?

Answer 76

3 ml at the inferior aspect of the greater cornu of the hyoid bone bilaterally. (SLN nerve block)

Question 77

The infant larynx is located?

Answer 77

C2-C4

Question 78

Tensor palatine dilator muscle opens the a. oropharynx b. nasopharynx c. hypopharynx

Answer 78

b. nasopharynx

Question 79

Genioglossus dilator muscle opens the a. oropharynx b. nasopharynx c. hypopharynx

Answer 79

a. oropharynx

Question 80

hyoid dilator muscles open the a. oropharynx b. nasopharynx c. hypopharynx

Answer 80

c. hypopharynx

Question 81

What are the three landmarks for Larson's maneuver?

Answer 81

Mastoid process skull base Ramus of mandible

Question 82

Lung cells are called pneumocytes, which type of pneumocytes are present where gas exchange occurs?

Answer 82

Type I