Airway Anatomy & Management

Question 1

Pharynx Divisions and Borders (3 items)

Answer 1

1. Nasopharynx (nose => soft palate)
2. Ororpharynx (mouth => uvula)
3. Laryngopharynx (includes epiglottis)

Question 2

Nasopharynx Structures and Innervation

Answer 2

1. Septum, Turbinates, Adenoids

2. Trigeminal (CN V)

Question 3

Oropharynx Structures and Innervation

Answer 3

1. Teeth, tongue, hard palate, soft palate
   2 a. Trigeminal CN V (hard/soft palate, ant 2/3 tongue)
   b. Glossopharyngeal CN IX (soft palate, posterior 1/3
   tongue)

Question 4

Larynx Location

Answer 4

C4-C6

Question 5

9 Larynx Cartilages (6 items)

Answer 5

3 Paired Cartilages
    a. Arytenoid
    b. Corniculate
    c. Cuneiform
3 Unpaired    
    a. Thyroid  
    b. Cricoid  
    c. Epiglottis

Question 6

3 Unpaired Larynx Cartilages

Answer 6

1. Thyroid: anterior attachment for vocal chords
2. Epiglottis: covers opening to larynx
3. Cricoid: narrowest part of pediatric airway

Question 7

3 Paired Larynx Cartilages

Answer 7

1. Arytenoid: posterior attachment for vocal chords
2. Corniculate: posterior portion of aryepiglottic fold
3. Cuneiform: lateral to corniculates on aryepiglottic fold

Question 8

Glottic Opening

Answer 8

Triangular fissure between vocal chords; narrowest portion of adult airway

Question 9

Lateral Cricoarytenoid Muscle

Answer 9

Controls glottic opening, adducts the vocal cords (Let’s Close the Airway)

Question 10

Arytenoid Muscles

Answer 10

Control glottic opening; has oblique and transverse components; adducts the vocal cords

Question 11

Posterior Cricoarytenoid Muscle

Answer 11

Control glottic opening; only vocal cord abductors (Please Come Apart)

Question 12

Cricothyroid Muscle

Answer 12

Controls vocal cord length; tenses/elongates cords

Question 13

Thyroarytenoid Muscle

Answer 13

Controls vocal cord length; relaxes/shortens vocal cords

Question 14

Vocalis Muscle

Answer 14

Controls vocal cord length; relaxes/shortens vocal cords

Question 15

Innervation of Laryngeal Muscles

Answer 15

1. Cricothyroid: Superior Laryngeal Nerve (branch of Vagus CN X)
2. All Others: Recurrent Laryngeal Nerve (Vagus CN X)

Question 16

Lower Airway: Anatomical Deadspace (5 items)

Answer 16

1. Trachea
2. Carina
3. Bronchi
4. Bronchioles
5. Terminal Bronchioles

Question 17

Lower Airway: Anatomical Respiratory (2 items)

Answer 17

1. Respiratory Bronchioles

2. Alveoli

Question 18

Trachea Anatomy:

1. Length
2. Diameter
3. Cartilage #
4. Carina Location
5. Right Bronchi (Length/Angle)
6. Left Bronchi (Length/Angle)

Answer 18

1. 10-20cm
2. 22mm
3. 16-20 U shaped rings (no cartilage posterior)
4. C4
5. 2.5cm long, 25 degrees (short/fat)
6. 5cm long, 45 degrees (long/lean)

Question 19

Mallampati Classification:

1. Technique
2. 4 Classes (PUSH)

Answer 19

1. Pt sits upright, head neutral, mouth open/tongue protruded maximally (no Ahhhhh)
2. Classifications:
   Class 1: Faucial pillars, entire Uvula, Soft and Hard palate Class 2: Uvula tip masked by tongue, Soft and Hard palate
   Class 3: Soft and Hard palates (uvula base only)
   Class 4: Hard palate

Question 20

Cormack and Lehane Score (4 Grades)

Answer 20

Grade 1: most of glottis visible
Grade 2: Only posterior portion of glottis visible
Grade 3: Only epiglottis visible
Grade 4: No airway structures visible(Grades 3/4 must use video assisted intubation)

Question 21

Thyromental Distance:

1. Technique
2. Indications

Answer 21

1. Fully extend next; measure from lower border of mandible till the thyroid notch; normal is 6-6.5cm or 4 fingerbreadths
2. <3 fingerbreadths indicates receding mandible or “anterior airway”; difficult intubation

Question 22

Mandibular Protrusion Test (3 Classes)

Answer 22

Class A: lower incisors can be protruded anterior to upper incisors
Class B: lower incisors brought edge to edge with upper
Class C: lower incisors cannot be brought edge to edge with upper incisors*Test indicates how easy it is to jaw thrust

Question 23

MSMAID of Induction

Answer 23

Monitors on and calibratedSuction at head of bedMachine checkAirwayIVDrugs (emergency and case specific)

Question 24

Airway Setup Components (12 items)

Answer 24

1. Face mask (appropriate size)
2. Ambu bag (or PPV in APL)
3. Suction
4. Tongue Depressor
5. Oral/Nasal Airways (appt. size)
6. Laryngoscope Handle (check battery)
7. 2 different blades
8. 2 ETT tubes (different sizes)
9. Stylet
10. Syringe
11. LMA
12. Tape

Question 25

Face Masks: 1. Sizes 2. Holding technique

Answer 25

1. Size 1 (neonate) => Size 6 (large adult) | 2. C/E grip with left hand; put 4/5th finger at angle of mandible for chin lift/ jaw thrust

Question 26

Pre-oxygenation Goal/Techniques

Answer 26

Goal: complete washing out of nitrogen Technique: 1. 3-5 minutes @ 100% >6L/min flow (10 mins safe apnea) 2. 4 VC breaths within 30 sec @ 100% >6L/min flow (5 mins safe apnea)

Question 27

Oral Airways: 1. Types 2. Sizes 3. Measurement 4. Complications

Answer 27

1. Berman (BOA) or Guedel 2. a. Small: BOA 80mm = Guedel #3 b. Medium: 90mm = #4 c. Large: 100 = #5 3. Measure from corner of mouth to earlobe 4. Unconscious patients only; soft tissue damage, laryngospasm

Question 28

Nasal Airway: 1. Types 2. Sizes 3. Measurement 4. Complications

Answer 28

1. Measured in French 2. 24-36; diameter depends on ease of insertion 3. Measure from nares to meatus of ear 4. Don't push if too much resistance; lubricate; can cause epistaxis/fractures; can be used on conscious patients

Question 29

Laryngoscope Blades: 1. Types 2. Sizes 3. Usage

Answer 29

1. Mac and Miller 2. Mac 1-4 (M 3,4/ F2,3) Miller 0-4 (M 3,4/ F 2,3) 3. Mac: scoop R => L, wrist straight, tip @ vallecula (depression behind root of tongue) Miller: straight back, better for anterior airway/ peds; tip on epiglottis

Question 30

Enodtrachial Tubes: 1. Types (6) 2. Typical sizes 3. Ideal Position

Answer 30

1. Cuffed, uncuffed, Oral RAE, Nasal RAE, Double Lumen, Reinforced 2. F: 6.5-7mm, M: 7.5-8mm 3. 4cm above carina; 2cm below vocal cords; M=23mm, F=21 cm; IDx3 for appx peds

Question 31

Sniffing Position: 1. Landmarks 2. 3 Axis

Answer 31

1. Tragus even with sternum | 2. Aligns oral, pharyngeal, laryngeal axis

Question 32

Laryngeal Mask Airway: 1. Sizes 2. Insertion 3. Advantages 4. Disadvantages

Answer 32

1. a. LMA 3 (30-50kg) b. LMA 4 (50-70kg) c. LMA 5 (70-100kg) d. LMA 6 (>100kg) 2. Have 20-50cc syringe; lubricate; hold w/ black line facing away and insert till resistance; inflate, ventilate, auscultate, tape 3. Speed/ease, improved hemodynamic stability, reduced anesthetic requirements, lower coughing 4. No positive pressure, increase risk of gastric insuflation/aspiration, can't use mechanical ventilation (must be spontaneously breathing)

Question 33

Mask Case Indications (6 items)

Answer 33

1. No difficult airway 2. No access to head needed 3. No excess secretions 4. Short duration 5. No position changes 6. No NMB (spontaneous ventilation)

Question 34

LMA Case Indications (6 items)

Answer 34

1. No difficult airway 2. No access to head needed 3. No excess secretions 4. Short duration 5. Need hands free during case 6. No NMB (spontaneous ventilation)

Question 35

ETT Case Indications (6 items)

Answer 35

1. Airway compromise/inaccessible 2. Long cases 3. Access to head needed 4. Controlled ventilation needed 5. Aspiration risk 6. NMB use