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Intro To Anesthesia > Airway > Flashcards

Flashcards in Airway Deck (46):
1

Cormack and Lehane Score

Laryngoscopic view of the glottis

Grade I: most of the glottis visible

Grade II: Only the posterior portion of glottis visible

Grade III: Only epiglottis visible

Grade IV: No airway structures visualized

2

carina

where trachea bifurcates.

Left and right sides come off at different angles. 

right bronchi is 2.5 cm long with 25 degree angle

left bronchi is 5cm long with a 45 degree angle

 

3

Thyroarytenoid

shortens and relaxes the vocal cords

4

Pharynx

  • nasopharynx
    • border is soft palate
  • oropharynx
    • border is the epiglottis
    • includes tonsils, uvula

Glossopharyngeal (CN IX)

Vagus (CN X)

5

Oral airways

measure from the corner of the mouth to the earlobe

  • use tongue depressor to insert
  • Complications:
    • laryngospasm
    • bleeding
    • soft tissue damage
  • 2 types: Berman (BOA) and Guedel (hollow)
    • small- BOA 80mm / Guedel 3
    • medium- BOA 90mm / Guedel 4
    • large - BOA 100mm / Guedel 5

6

MAC case

Monitored Anesthesia Care 

  • Spontaneously breathing patient
  • Always have COMPLETE airway setup ready to go
  • Nasal Cannula (everybody gets O2)
    • 2L NC = 28% FiO2
    • 6L NC = 45% FiO2
  • Nasal airway if snoring

7

Nasal airways

measure from distance of nare to meatus of ear

  • Tolerated better than oral airway with light sedation
  • lubricate
  • complications:
  • epistaxis (nose bleed), nasal or basal scull fractures, adenoid hypertrophy

8

lower airway

trachea

carina

bronchi

bronchioles

terminal bronchioles

respiratory bronchioles

alveoli

 

9

Glossopharyngeal Nerve (CN IX)

 

  • Posterior 1/3 of tongue
  • soft palate
  • oropharynx

10

Airway set up

  1. appropriately sized face mask
  2. ambu bag, circuit (for pos pres)
  3. suction
  4. tongue depressor
  5. oral and nasal airways
  6. laryngoscope handle
  7. 2 different blades
  8. ETT, 2 sizes
  9. stylet
  10. syringe
  11. LMA
  12. tape

11

Larynx

Located at C4-C6 in an adult

 

Functions: airway protection, respiration, phonation

12

Macintosh blade

  • Inserted in vallecula above epiglottis

13

Optimal intubating position

"sniffing"

Oral, pharyngeal, and laryngeal axis

Most optimal for visualization of vocal cords and most effective mask ventilation

14

Mallampati score

Pt sitting upright, head neutral mouth open as wide as possible and tongue maximally protruded.  No AAAH!

  • Correlates the oropharyngeal space with the ease of direct laryngoscopy and tracheal intubation.
    • When the base of the tongue is disproportionately large, the tonge overshadows the larynx resulting in difficult exposure of the vocal cords during laryngoscopy. 

No AAAH!

 

15

Pre- Oxygenation

  • Goal to increas O2 concentration in functional residual capacity (FRC) by "washing out" nitrogen in the FRC with O2
    • 3-5 minutes of tight mask with normal breathing and 100% FiO2
      • = 10 minutes of safe apnea time
    • 4 vital capacity breaths within 30 seconds with 100% FiO2
      • =5 minutes safe apnea time. 

16

glottic opening

triangular fissure between the cords

*Narrowest portion of the adult airway

 

17

Miller blade

  • Inserted below epiglottis 

18

ETT

*always have two sizes available

  • Female: 6.5-7.0 mm (depth ≈ 21 cm)
  • Male: 7.5-8.0 mm (depth ≈23 cm)

 

  • Ideal position: 4 cm above carina and 2 cm below vocal cords
  • All ETT have 15mm outer diameter universal connector

19

Trachea

Fibromuscular

10-20 cm length, 22 mm diameter

no cartilage on posterior side

bifurcates at T-4 (carina)

20

Lateral Cricoarytenoid

Closes the glottis

21

just remember where all that shit is

22

3 paired cartilages of Larynx

Arytenoid

Corniculate

Cuneiform

23

arytenoids

closes the glottis, especially posterior

24

Intrinsic Laryngeal muscles

  • Control the movements of the laryngeal cartilages
    • length and tension of cords and size of glottic opening
  • Cricothyroid muscle innervated by the external branch of the superior laryngeal nerve, a branch of the Vagas nerve (CN X)
  • All others innervated by the recurrent laryngeal nerve, a branch of the Vagus nerve (CN X)
  1. posterior cricoarytenoid
  2. lateral cricoarytenoid
  3. arytenoids
  4. cricothyroid
  5. thyroarytenoid

25

3 unpaired cartilages of the Larynx

Thyroid

Cricoid

Epiglottis

26

Thyromental Distance

  • Distance from lower border of mandible to thyroid notch with neck fully extended
    • Normal 4 fingerbreadths (6-6.5 cm)
  • Difficult intubation <3 fingers

27

Nasal passage innervation

Branches of the trigeminal nerve (CN V)

28

Laryngospasm

Sever, sudden, sustained contraction of the glottic opening in response to stiumlus.  Causes complete airway obstruction!!

Treatments:

Jaw life and mask

O2 with positive pressure

removal of stimulus

small dose of muscle relaxant Succinylcholine

29

Pre-op airway assessment

  1. general appearance
  2. Malampati classification
  3. range of motion of neck
  4. thyromental distance
  5. dentition
  6. mouth (lips, gums, tissues)
  7. mouth oppening (2-3 fingers)
  8. teeth (missing, protrusions, overbite, bridges out)
  9. size and mobility of tongue
  10. body habitus
  11. Hx of difficult intubation

*aspiration risk (hiatal hernia, GERD, recently ate, OSA)

 

30

Vocal cords

  • formed by the thyroarytenoid ligaments
  • appear pearly white
  • attached anteriourly to the thyroid cartilage and posteriourly to the arytenoid cartilages

31

Nasal passage includes:

  • septum
  • turbinates
  • adenoids
  • paranasal sinuses

32

Cricoid cartilage

Complete cartilaginous ring

Narrowest point of the pediatric airway

inferior to thyroid cartilage and cricothyroid membrane

33

Trigeminal Nerve (CN V)

sensory and motor

  • Hard and soft palate
  • anterior 2/3 of tongue

34

Mallampati classes

  1. faucial pillars, entire uvula, soft and hard palates.
  2. Uvula tip masked by tongue, soft and hard palates
  3. Soft and hard palates, uvula base only
  4. Hard palate only

 

PUSH

pillars, uvula, soft palate, hard palate

35

Ensuring airway patency

  1. Airway maneuvers (heat tilt/chin lift, jaw thrust)
  2. Adjuncts (Nasal or oral airway)
  3. Two handed mask with bagging assistance. 

**obstruction usually caused by tongue and epiglottis due to the relaxation of the genioglossus muscle

36

Function of nasal passage

  • humidification
  • filter
  • warm
  • *accounts for 2/3 of total upper airway resistance

37

posterior cricoarytenoid

muscle of the Larynx

*Separates the vocal cords and opens the gottis

38

LMA

  • Supraglottic airway device
  • used for routine AND difficult airway management
  • can be used as conduit for ETT placement
  • sizing based on weight
    • 30-50kg--> LMA 3
    • 50-70kg --> LMA 4
    • 70-100kg --> LMA 5
    • >100 kg --> LMA 6
  • Can be used for positive pressure but is not meant for it
    • only positive pressures below 15.

39

General anesthesia Mask case

  • Can be used when:
    • no difficult airway
    • surgeon does not need access to head/neck
    • no airway bleeding/secretions
    • short case
    • no position changes and easy access to head
    • obstruction easily relieved with oral or nasal airway
    • no neuromuscular blocker used--spontaneous breathing

40

Tracheal intubation indications

  1. airway compromise
  2. airway inaccessible
  3. long surgical time
  4. surgery of head, neck, cheek, or abdomen
  5. need for controlled venticalion and/or PEEP
  6. Inability to maintain airway with mask/LMA
  7. aspiration risk
  8. airway/lung disease

41

LMA insertion

  1. position head: neck flexed and head extended
  2. hold LMA with right hand like a pen, black line facing you
  3. Insert lubricated LMA into mouth, follow palate centrally, push into oropharynx until resistance is felt, then stop
  4. release right hand, grasp upper aspect of LMA, and attempt further advancement
  5. inflate the cuff (LMA will move)
  6. ventilate: observe, listen
  7. secure with tape

42

LMA advantages over ETT

  1. increased speed and ease of placement
  2. improved hemodynamic stability at induction and emergence
  3. reduced anesthetic requirements
  4. lower frequency of coughing during emergence
  5. lower incidence of sore throats
  6. avoids "foreigh body" in trachea
  7. pt can be fully emerged before removal. (good for asthma patients)

43

LMA disadvantages

  1. lower seal pressure
  2. high frequency of gastric insufflation
  3. esophageal reflux more likely
  4. inability to use mechanical ventilation

44

Potential hazards in airway management

  1. dental damage
  2. soft tissue/mechanical injury
  3. laryngospasm
  4. bronchospasm
  5. vomiting/aspiration
  6. hypoxemia/hypercarbia
  7. SNS stimulation
  8. esophageal/endobronchial intubation
  9. sore throat

45

General anesthesia LMA case

  1. difficult airway not present ??
  2. surgeon does not need access to head/neck
  3. no airway bleeding/secretions
  4. case of short duration
  5. more reliable patent airway than mask
  6. want hands free

46

General Anesthesia ETT case use when:

  1. airway compromise
  2. airway inaccessible
  3. long surgical time
  4. alternate surgical positions
  5. surgery of head, neck, cheek, or abdomen
  6. need for controlled ventilation and PEEP
  7. inability to maintain airway with mask/LMA
  8. aspiration risk
  9. airway/lung disease