airway anatomy

Question 1

what cranial nerve is trigeminal

Answer 1

CN 5

Question 2

what are the 3 branches of trigeminal

Answer 2

V1- opthalmic
V2- maxillary
V3- mandibular

Question 3

V1 branch of trigeminal

Answer 3

opthalmic

sensory to nares and anterior 1/3 of nasal septum

Question 4

v2 branch of trigeminal

Answer 4

maxillary

sensory to turbinates and nasal septum

Question 5

v3 branch of trigeminal

Answer 5

mandibular

sensory to anterior 2/3 of tongue

Question 6

what nerve is glossopharngeal

Answer 6

CN9

-sensory for soft palate, oropharynx-> anterior side of epiglottis (valecula)
-afferent limb of gag reflex
-motor for swallowing and phonation

Question 7

what nerve is vagus

Answer 7

cn 10

Question 8

what does vagus divide into

Answer 8

SLN (internal and external)
RLN

Question 9

where does SLN divide into branches

Answer 9

at level of hyoid bone

Question 10

SLN internal branch

Answer 10

SENSORY to posterior side of epiglottis-> vocal cords

penetrates thyrohyoid membrane

Question 11

SLN external branch

Answer 11

motor to cricothyroid membrane (tenses vocal cords)

bilateral injury-> hoarseness but no resp distress

Question 12

RLN

Answer 12

sensation and motor

sensory from below VC-> trachea

motor: all intrinsic muscles of larynx (thryoarytenoid, lat cricoarytenoid, post cricoarytenoid)

Question 13

what happens with unilateral injury to RLN

Answer 13

no respiratory distress

Question 14

what happens with acute bilateral injury to RLN

Answer 14

respiratory distress from unopposed action of cricothyroid m

Question 15

what happens with bilateral chronic injury of RLN

Answer 15

no respiratory distress

Question 16

risk factors for bilateral RLN injury

Answer 16

-overinflation of ETT/LMA
-excessive neck stretching
-neck surgery (thyroidectomy most common)

Question 17

risk factors for specific L sided RLN injury

Answer 17

-PDA ligation
-L atrial enlargement (mitral stenosis
-aortic arch aneurysm
-thoracic tumor

Question 18

what side of RLN is more susceptible to injury

Answer 18

Left! loops around aortic arch

Question 19

how to do a glossopharyngeal block

Answer 19

inject at base of palatoglossal arch (anterior tonsillar pillar) to depth of 0.25-0.5 cm

inject 1-2 cc local

Question 20

risks with glossopharyngeal block

Answer 20

seizure from accidental intracarotid injection

Question 21

how to do sueprior laryngeal injection

Answer 21

inject at inferior border of greater cornu of hyoid bone (1 mL outside of thyrohyoid membrane) and 2 mL deep to this structure

Question 22

how to block RLN

Answer 22

transtracheal block- insert needle through cricothyroid membrane in CAUDAL direction

pt takes deep breath- inject 3-5 cc of local into tracheal lumen

Question 23

landmarks for larynx

Answer 23

anterior to c3-c6

Question 24

tensor palantine role

Answer 24

opens nasopharynx

obstruction at level of soft palate

Question 25

genioglossus role

Answer 25

opens oropharynx obstruction at level of tongue

Question 26

hyoid muscle role

Answer 26

opens hypopharynx

Question 27

what are the unpaired cartilages

Answer 27

thyroid, cricoid, epiglottis

Question 28

what are the paired cartilages

Answer 28

arytenoid, corniculate, cuneiform

Question 29

what is the narrowest region in the airway for adults

Answer 29

glottic opening

Question 30

trachea begins and ends at

Answer 30

cricoid cartilage (c6)- carina (t4/5)

Question 31

trachea rings open posterior or anterior

Answer 31

posterior

Question 32

what cells produce mucus in the trachea

Answer 32

goblet

Question 33

where is carina located

Answer 33

t4/5 angle of louis

Question 34

R vs L bronchus

Answer 34

L bronchus 5 cm 45 degrees R bronchus 2.5 cm 25 degrees

Question 35

how are bronchi different in children

Answer 35

children up to 3 - both bronchi take off at 55 degrees

Question 36

whats different in airway bifurcations

Answer 36

decreased airflow velocity, cartilage, cilia, and goblet cells

Question 37

type 1 pneumocytes

Answer 37

provide surface for gas exchange

Question 38

type 2 pneymocytes

Answer 38

produce surfactant- can also produce type 1

Question 39

type 3 pneumocytes

Answer 39

macrophages, fight infection

Question 40

laryngospasm reflex arc

Answer 40

afferent limb: internal branch of SLN efferent limb: external branch of SLN (cricothyroid m.) and RLN (lateral cricoarytenoid and thyroarytenoid m.)

Question 41

complications from laryngospasm

Answer 41

airway obstruction, neg pressure pulm edema, pulm aspiration of gastric contents, cardiac dysrhythmias, cardiac arrest, death

Question 42

s/s of laryngospasm

Answer 42

inspiratory stridor, suprasternal/ supraclavicular retractions, "rocking horse", apperance of chest wall, increased diaphragmatic excursion, lower rib flailing, absent/ altered etco2 waveform

Question 44

causes of laryngospasm

Answer 44

airway manipulation (light anesthesia), secretions, airway surgery, active or recent resp infeciton (<2 weeks), age < 1 yr

Question 45

tx of laryngospasm

Answer 45

fio2 100% remove stimuli, deepen anesthesia, larsons, chin lift, cpap 15-20, succ

Question 46

succ dose adult/child

Answer 46

IV 0.1-1 mg/kg IM=4 mg/kg

Question 47

succ neonate/ infant dosing

Answer 47

IV = 2 mg/kg IM = 5 mg/kg

Question 48

succ give with atropine ___ mg/kg in children < _ yrs

Answer 48

0.02 mg/kg in children < 5 yrs old

Question 49

larsons maneuver is also called

Answer 49

laryngospasm notch pressure applied backward bilateral toward skull base for 3-5 seconds than released 5-10 sec

Question 50

borders for larsons

Answer 50

superior= skull base anterior= ramus of mandible posterior= mastoid process