Airway Flashcards
1
Q
Where are the turbinates?
A
nasal passages
2
Q
What are the turbinates?
A
hard ridges of cartilage bottom turbinate is a bone in itself
3
Q
Function of nasal passages
A
warms, humidifies, and filters air
(air becomes “turbinate” and creates non linear flow, which is what heats up air)
accounts for 2/3 total upper airway resistance
4
Q
When the pharyngeal tonsils become inflamed, what are they referred to as?
A
Adenoids
5
Q
Components of nasal passage anatomy
A
septum
turbinates
adenoids
6
Q
Innervation of nasal passages
A
Branches of the trigeminal nerve (CN V)
7
Q
Components of oral cavity anatomy
A
teeth
tongue
hard palate
soft palate
8
Q
Hard and soft palate innervation
A
trigeminal nerve (CN V)
9
Q
Innervation of anterior 2/3 tongue
A
Trigeminal nerve (CN V)
10
Q
Innervation of posterior 1/3 tongue
A
glossopharyngeal nerve (CN IX)
11
Q
Innervation of soft palate (mostly uvula)
A
glossopharyngeal nerve (CN IX)
12
Q
Innervation of oropharynx
A
glossopharyngeal nerve (CN IX)
13
Q
What is the pharynx and what are its components?
A
Portion of the upper airway that connects the nasal and oral cavities to larynx and esophagus
- nasopharynx
- oropharynx
- hypopharynx/laryngopharynx
14
Q
components of nasopharynx
A
- starts posterior to turbinates, includes adenoids, ends at the tip of the uvula and soft palate
- Border is the soft palate
15
Q
Components of the oropharynx
A
- Border is the epiglottis
- Tonsils, Uvula
16
Q
Components of the laryngopharynx
A
Tip of epiglottis down to cricoid cartilage. It leads to the glottic opening.
17
Q
Innervation of superior components of the pharynx
A
Glossopharyngeal (CN IX)
18
Q
Innervation of inferior components of the pharynx
A
Vagus (CN X) (laryngopharynx)
19
Q
Where is the larynx located in regard to the spine?
A
C4-C6 in the adult
20
Q
Functions of larynx
A
Airway protection (with epiglottis)
Respiration
Phonation (with air passing through vocal cords)
21
Q
Unpaired cartilages of the larynx
A
- Thyroid
- Cricoid
- Epiglottis
22
Q
Paired cartilages of the larynx
A
- Arytenoids
- Corniculates
- Cuneiforms
23
Q
Describe the thyroid cartilage
A
Unpaired cartilage of the larynx
Large and most prominent
Anterior attachment for vocal cords.
24
Q
Describe the epiglottis
A
Unpaired cartilage of the larynx
Cartilaginous flap that serves as the anterior border of the larygneal inlet
Covers opening to the larynx during swallowing
25
Describe the cricoid cartilage
Unpaired cartilage
Only complete cartilaginous, signet - shaped, ring
Narrowest portion of the pediatric airway
26
Describe the arytenoids
* Paired cartilages of the larynx
* Attach directly to the cricoid cartilage
* Posterior attachment for vocal cords
* Falsely identified in an anterior airway
27
What attaches posteriorly and anteriorly to the vocal cords?
Anterior: thyroid cartilage
Posterior: arytenoids
28
Describe the corniculates
Paired cartilages of the larynx
Posterior portion of the aryepiglottic fold
29
Cuneiforms
Paired cartilages of the larynx
Located lateral to the corniculates in the aryepiglottic fold; not always present
30
Describe the vocal cords
Appear pearly white
Formed by the thyroartyenoid ligaments
Attached anteriorly to the thyroid cartilage and posteriorly to the arytenoid cartilages
31
Describe the glottic opening
Opening leading to trachea
Triangular fissure between the cords
Narrowest portion of the adult airway
32
Function of lateral cricoarytenoids
Intrinsic laryngeal muscle that adducts the vocal cords
"Lets close the airway"
33
Arytenoid Muscles
Intrinsic laryngeal muscle (oblique arytenoids and transverse arytenoids) that adduct the vocal cords
34
Function of the posterior cricoarytenoid
Intrinsic laryngeal muscle that abducts the vocal cords
"Please come apart"
35
Function of the cricothyroid muscle
Intrinsic laryngeal muscle that tenses/elongates vocal cords
"**c**ords **t**ense"
36
Function of thyroarytenoid muscle
Intrinsic laryngeal muscle that relaxes/shortens vocal cords
"**t**hey **r**elax"
37
What is the vocalis?
Intrinsic laryngeal muscle that relaxes/shortens vocal cords
38
Function of the intrinsic laryngeal muscles
* Control the movements of the laryngeal cartilages
* Control the length and tension of the vocal cords and the size of the glottic opening
39
Except for the cricothyroid muscle, what is the innervation for the other intrinsic larygeal muscles?
The recurrent laryngeal nerve, a branch of the vagus nerve (CN #10)
40
Describe the innervation of the cricothyroid muscle.
Innervated by the **_external branch_** of the **_superior laryngeal nerve_**, a branch of the **_Vagus nerve_** (CN X)
41
True or False: the _internal laryngeal nerve_, of the _superior laryngeal nerve_ is purely sensory.
True.
the _external laryngeal nerve_ is motor and innervates the cricothyroid muscle.
42
Function of extrinsic laryngeal muscles
Move larynx up or down as a whole
43
What is the suprahyoid group of the extrinsic laryngeal muscles responsible for?
Raising larynx cephalad (or up towards the head)
44
What is the infrahyoid group of the extrinsic laryngeal muscles responsible for?
Moving the larynx caudad (or down)
45
Components of lower airway
* Trachea
* Carina
* Bronchi
* Bronchioles
* Terminal bronchioles
* Respiratory bronchioles
* Alveoli
46
Describe the anatomy of the trachea
Fibromuscular tube
10 - 20 cm length; 22 mm diameter (adult)
16-20 U shaped cartilages *(non-complete cartilages)*
Posterior side lacks cartilage *(cartilage on anterior side only; posterior side is muscle)*
Bifurcates at lower border of T4--carina
47
Where does the trachea birfuctate?
The carina, at the lower border of T4
48
What happens to the trachea at the carina?
It bifurcates, dividing the trachea into right and left mainstem bronchi
49
Compare and contrast the right and left bronchus
Right bronchus is 2.5 cm long and branches off at an angle of 25°
Left bronchus is 5 cm long with an angle of 45º
50
Who should get an airway assessment?
EVERYONE
regardless of whether you work with the for 5 minutes or \>12 hours.
regardless of types of procedure taking place.
51
What is the greatest predictor of a difficult airway?
"No single test has been devised to predict a difficult aiway accurately 100% of the time"
\*previous difficult intubation should *always* raise suspicion\*
\*\*It is not one factor but a combination oof factors that create the difficult airway\*\*
52
Questions/factors to consider for airway assessment
* Radiation or burn to head/neck
* Abscess or tumor
* Prior intubation or tracheostomy (old trach scar?)
* Dysphagia, stridor, hoarse voice quality
* Snoring or sleep apnea
* TMJ pain
* C spine pain or LROM
* Rheumatoid arthritis
* Ankylosing spondylitis
53
Airway Assessment
* General appearance (head, neck size and fullness)
* Range of motion
* Mouth (tongue, lips, tissues, gums/bleeding or friable tissue?)
* Mouth opening (30-40 mm or 2-3 fingers)
* Dentition
* Body habitus (pregnancy, large breasts)
* Diagnosis
* Planned surgery
* Mallampati classification
* Mandibular Protrusion test
* Thyromental distance
54
What is the Mallampati Classification?
* Correlates the oropharyngeal space with the ease of direct laryngoscopy and tracheal intubation
* Hypothesis: when the base of the tongue is disproportionately large, the tongue overshadows the larynx resulting in difficult exposure of the vocal cords during laryngoscopy
55
How do you assess the Mallampati Score?
Pt sitting upright, head neutral, mouth open as wide as possible and tongue maximally protruded. _No AAAAHH!_
56
What can be seen with Mallampati Class I?
faucial Pillars, entire Uvula, Soft and Hard palates
## Footnote
Generally associated with easy intubation.
"Think "P.U.S.H."
**P**illars, **U**vula, **S**oft Palate, **H**ard Palate
57
Which component of the mouth is the predominate cause of airway resistance in the oral cavity?
Tongue
58
In the oral cavity, the glossopharyngeal nerve (CN IX) innervates which structures?
* posterior 1/3 tongue
* soft palate (mostly uvula)
* oropharynx
59
In the oral cavity, the trigeminal nerve (CN V), innervates which structures?
* hard and soft palate
* anterior 2/3 tongue
60
Laryngospcopic view of the epiglottis
61
Anatomy of the larynx
62
Mallampati Class II
**U**vula tip masked by tongue, **S**oft and **H**ard palates
63
Mallampati Class III
**S**oft and **H**ard palates; uvula base only
64
Mallampati Class IV
**H**ard palate only
65
When is the best time to try a new airway technique?
Novel techniques for difficult AW management must be learned and practiced in a controlled environment with non-challenging airways.
_***\*\*AN EMERGENCY IS NOT THE TIME TO A TRY A NEW TECHNIQUE\*\****_
66
What is the pharynx?
A muscular tube that extends from the base of the skull down to the level of the cricoid cartilage and connects the nasal and oral cavities with the larynx and esophagus.
67
(From the book) The pharyngeal musculature in the awake patient helps maintain airway patency; loss of pharyngeal muscle tone is one of the primary causes of\_\_\_\_\_\_\_ ________ \_\_\_\_\_\_\_\_\_\_ during anesthesia.
upper airway obstruction
68
A chin lift with mouth closure increases longitudinal tension in the _________ muscles, counteracting the the tendency of the _________ airway to collapse.
pharyngeal; pharyngeal
69
What is the larynx?
complex structure of cartilage, muscles, and ligaments that serves as the inlet to the trachea and anterior commisure
70
The space between the vocal cords is termed the \_\_\_\_\_\_\_\_.
glottis (book p 1378)
71
Describe the Cormack and Lehane Score
The actual laryngospic view of the glottis
The Mallampati class is correlated to what can be seen on direct laryngoscopy.
Grade I: most of the glottis visible
Grade II: Only the posterior portion of the glottis visible
Grade III: Only epiglottis visible
Grade IV: No airway structures visualized
72
Cormack and Lehane Score: Grade I
Most of the glottis visible
73
Cormack and Lehane Score: Grade II
only the posterior portion of the glottis visible
74
Cormack and Lehane Score: Grade III
Only epiglottis visible
75
Cormack and Lehane Score: Grade IV
No airway structures visualized, no visualization of epiglottis or larynx
76
Describe thyromental distance
Distance from lower border of mandible to thyroid notch with neck fully extended *(mentum to thyroid cartilage)*
**Normal**: _6-6.5 cm_ (or 4 fingerbeadths)
Difficult intubation with \< 3 fingers = receding mandible or reduced mandibular space
- termed "anterior larynx" or "anterior airway" (larynx actually moves up closer to head)
- angle of intubation is more difficult
77
Describe the classes of the mandibular protrusion test and the significance of each class.
78
Describe the pneumonic for preparing for induction
* **M**onitors on and settings appropriate (*VS alarms appropriate, always have beep associated with pulse and sat probe so you can monitor for changes immediately*)
* **S**uction ON and at *_head of bed_* (ON + continuous + HOB)
* **M**achine checked, means of positive pressure ventilation - ambu bag ALWAYS
* **A**irway - complete airway set up (multiple ETTs-one of same size and half size smaller, LMA, oral airway, nasal airway, laryngoscope handle, multiple laryngoscope blades)
* **I**V access, 1 or 2 sufficient working IVs, blood tubing? fluid warmer?
* **D**rugs (emergency and case/patient specific)
* **S**pecial equipment (i.e. positioning aids)
79
Describe the components of an airway set up
* Means of PPV - ambu bag, machine circuit, O2 source
* Appropriate sized face mask
* Appropriate sized laryngeal mask airway (LMA) - (either planned airway for case or difficult airway adjunct) - this is a supraglottic airway
* Appropriate sized oral and nasal airways
* Tongue depressor (aids with oral airway insertion)
* Endotracheal tube (ETT) - 2 sizes, appropriate size + 1/2 to full size smaller
* Laryngoscope handle
* 2 different blades
* Suction ON and _easily accessible_
* Stylet
* Syringe
* Tape
80
What are some patient characteristics that may predict a difficult anesthetic mask fit?
Beard
Edentulous (no teeth) - easy intubation, difficult masking
Short mandible
81
True or false: head straps can cause potential nerve injuries.
True
Can also be difficult for patients with claustrophobia
82
Describe the technique for masking
* Hold mask in left and resevoir bag in right.
* Put thumb on upper aspect of the the mask, index and middle fingers on lower aspect, and 4th/5th fingers under chin for chin lift/jaw thrust.
* Try to keep fingers on bridge of the jaw bone, not soft tissue
83
Placement of fingers on the soft tissues of the neck while masking can occlude the airway of which population?
Pediatric population
84
How do you mask ventialte someone if the masking requires you to use both hands?
Utilize a resource in the OR to squeeze the bag to ventilate while you hold the mask in place with both hands.
85
Why do we use mask ventilation?
Preoxygentaion for induction
Post induction
86
What is the goal of pre-oxygenation?
Increase O2 concentration in functional residual capacity (FRC - volume of air left in the lung at end of passive expiration) by "washing out" nitrogen (79% in RA) in the FRC with oxygen.
87
How do we accomplish pre-oxygenation?
3-5 minutes of "tight" mask during normal tidal breathing with 100% FiO2 at \> 6L/min flow
This will equal 10 minutes of safe apnea time
88
If we don't have 3-5 minutes to pre-oxygenate, like in an emergency, what do we do?
4 vital capacity breaths within 30 seconds with 100% FiO2 at \>6L/min
Equal to 5 minutes of safe apnea time
89
How can we measure the effectiveness of our mask ventialtion?
* Chest rise
* Exhaled tidal volumes
* Pulse oximetry - readings and sound
* Capnography - ETCO2
90
For mask ventilation, adequate tidal volumes should be achieved with peak inspiratory pressures less than ____ cm H2O. Why should we avoid higher pressures?
**20 cm H2O**
Closing the APL (adjustable pressure limiting) to achieve higher volumes may be indicative of an airway obstruction (possibly the tongue).
**Note**: higher pressures don't necessarilly push air into the *lungs*, but rather into the *stomach →* causing gastric insufflation→putting the patient at higher risk for aspiration.
91
During mask ventilation, if we cannot achieve adequate tidal volumes at \< 20 cm H2O, what kinds of things should we assess?
Airway patency
Pulmonary compliance
92
List some predictors of difficult mask ventilation
* OSA or hx of snoring
* age \>55 years
* male
* BMI \> or = 30 kg/m2
* Mallampati class III or IV
* presence of a beard
* edentulousness
93
A common problem during induction of anesthesia is airway obstruction by the ______ and ______ due to relaxation of the ____________ muscle.
tongue; epiglottis; genioglossus
94
Name the two types of oral airways. Describe the difference in shapes and sizes.
**Berman (BOA)** and **Guedel**
**Guedel** has a hollow center - passageway for suction catheter if necessary
**Berman (BOA)** - solid, no passageway for catheter
Adult sizes:
* small BOA (80 mm) = Guedel #3
* medium BOA (90 mm) = Guedel #4
* large BOA (100 mm) = Guedel #5
95
How do you measure for proper sizing of an oral airway?
Center of the mouth to the angle of the jaw
OR
Corner of the mouth to the ear lobe
96
Should you use an oral airway for a patient that is semi conscious?
Why or why not?
No, oral airways are not well tolerated in awake or moderately awake patients. The patient should be "deep."
97
How do you measure proper sizing for a nasal airway?
Length - estimated as distance from nares to meatus of ear
Diameter - french sizes 24, 26....36
98
Visual steps of proper insertion of nasal airway. INFO CARD.
99
Discuss the uses for a nasal airway/nasal trumpet.
* Used to provide passageway, nose to pharynx, beneath the relaxed and obstructing tongue
* Used in series (small to large) to dilate prior to elective nasal intubation
* Usually tolerated better than oral airway during light anesthesia/possibly during emergence
100
Precautions/complications for a nasal trumpet
* Is the patient on anticoagulation?
* epistaxis
* nasal or basal skull fractures
* adenoid hypertrophy
101
Describe the differences between the laryngoscope handles discussed.
102
What components of the laryngoscope handle and blade need to be checked before use?
**Handles** - check the battery!
**Blades** - check the light! (to see if it's working _AND_ to make sure the light bulb is tight so it does not fall into the patient's airway!)
Connect handle and blade to ensure proper fit and working
Want one of each macintosh and miller blade for set up
103
Distinguish between a MAC blade and a Miller blade.
* MAC - Mactinosh
* sizing (1-4)
* Curved
* Miller
* sizing (0-4)
* straight
104
Discuss the intubation technique and how technique differs between using a MAC or Miller blade.
* A great time to test out using a miller blade is with an edentulous patient
* MAC base of blade sits in vallecula
* Miller is longer and picks up the epiglottis, but this makes the angle much smaller, so need to be careful of cracking teeth
105
Describe the proper way to open a mouth before inserting the blade.
* The scissors technique
* Should feel the jaw pop when opened
106
INFO CARD
Various ETT options
* Double Lumen ETT
* Lung isolation - deflate right, ventilate left(vice versa)
* Tubes with place for nerve monitoring
* could be used in thyroid surgery
107
What is the ideal postion for placement of ETT?
_4 cm_ above the *carina* and _2 cm_ below the *vocal cords*
**Males**: approximately 23 cm
**Females**: approximately 21 cm
If unsure (peds population): ID (internal diameter) x3
i.e. 4.0 mm = 12 cm
108
In general, which size ETTs should we use for adult males and females?
\*Want **TWO** sizes available\*
**Female**: 6.5-7.0 mm id (internal diameter)
**Male**: 7.5-8.0 mm id (internal diameter)
\*Consideration: if patient is planned to go back to ICU and remain intubated, consider larger ETT (8.0) for both males and females, unless notably small\*
109
How do we ALWAYS check for proper placment of our ETT?
* Bilateral breath sounds
* Bilateral chest rise
* Presence of etCO2
* note fogging breaths in tube
110
Gold standard for AW management.
Endotracheal Tube
111
Absolute indications and "other" indications for use of ETT.
* **Absolute indications**
* full stomach
* high risk for aspiration of gastric secretions or blood
* critically ill
* significant lung abnormalities (i.e. low lung compliance, high airway resistance, impaired oxygenation)
* surgery requiring lung isolation
* otorhinolaryngologic surgery (ENT, head/neck) where an SGA would interfere with surgical access (AW managment discussed with surgeon)
* anticipated need for post-operative ventilatory support
* failed SGA placement
* **Others**
* surgical requirement for NMBDs (neuromuscular blockade)
* positioning that does not allow quick access to the AW (i.e. prone)
* predicted difficult airway
* prolonged procedures
112
List and discuss the common features of an ETT.
* **Murphy eye******
* Additional distal opening in the side wall that acts as back-up portal for ventilation should the distal end of the lumen become obstructed
* **standard 15 mm adaptor**
* *common place of disconnect, needs tightening*
* **high volume, low pressure cuff**
* purpose: creates a seal to protect against gastric aspiration
* ensures tidal volume delivered reaches the lungs
* design decreases necrotic tissue occurence
* **Beveled tip**--facilitates passage through the vocal cords
* **Pilot balloon with one-way valve**
* needed for cuff inflation & assessment of cuff pressure
* minimal inflation volume to attain air leak
* ~20 - 25 cm H2O
113
What is the "Murphy's eye" of an ETT?
* Additional distal opening in the side wall of the ETT
* Back - up portal for ventilation should the distal end of the lumen become obstructed by either soft tissue or secretions
114
What is a stylet and how do we use it optimally?
* Helps to add rigidity to ETT
* Can use malleable stylet to shape ETT into *hockey stick shape*
* 60 degree angle formed 4 - 5 cm from distal end
* Removed when the tip of the ETT is right at the _level of the vocal cords_
* limits trauma to tracheal mucosa
* \*\*have someone help you remove stylet as you are still becoming comfortable with managing intubation\*\*
115
Describe the optimal intubating position.
* "Sniffing" position - aligns the 3 axis
* oral axis
* pharyngeal axis
* laryngeal axis
* provides the most optimal visualization of the *vocal cords*
* allows for the most effective mask ventilation
* positioning is _key_ for success, especially for the novice practitioner
116
Optimal Intubating Position
* "sniffing" positions aligns the 3 axes (oral, pharyngeal, and laryngeal)
* provides the most optimal visualization of the vocal cords
* allows for the most effective mask ventilation
* positioning is key for success (esp for novice practitioner)
Confirming horizontal alignment of the external auditory meatus with the sternal notch is useful for ensuring optimal head elevation in both obese and non-obese patients
117
Potential difficulty with intubation/Predictors of difficult laryngoscopy.
* Mallampati class III or IV
* Small mouth opening
* High, arched palate
* Long upper incisors
* Prominent overbite
* Inability to protrude mandible
* Short thyromental distance
* Short, thick neck
* Limited cervical mobility
118
In a general overview of the ASA Difficult AW Algorithm: if we can mask ventilate our patient, do we have an emergency on our hands?
No, if you can successfully mask ventilate your patient, you have time to decipher what is the problem, and try interventions, as long as you can continue to mask ventilate if interventions don't work.
The second you can no longer mask ventilate, you have an emergency.
You would then condsider SGA.
If SGA unsuccessful→EMERGENCY (may consider surgical airway)
119
What is a Laryngeal Mask Airway (LMA) and what is it used for?
* _Supraglottic_ airway device (SGA)
* Used for *routine* AND **difficult airway managment**
* Can be used as a conduit for ETT placement
* Appropriate size is based on patient _weight_
* adult sizes
* 30-50 kg → LMA 3
* 50-70 kg → LMA 4
* 70-100 kg → LMA 5
* \>100 kg → LMA 6
120
Equipment needed and steps of LMA insertion
* **Equipment**
* 20 or 50 cc syringe
* lubricant, suction, stehoscope, tape
* \*\*lubricate posterior/top side only\*\*
* if lubricated on bottom, lube can fall on to vocal cords, causing laryngospasm
* **Steps of Insertion**
* Position head - neck flexed and head extended
* Hold LMA with right hand like a pen with black line facing you
* Insert LUBRICATED LMA into mouth, follow palate centrally, push into oropharynx until resistance is felt, and then stop.
* Release right hand, grasp upper aspect of LMA, and attempt further advancement of the LMA
* Inflate cuff (LMA will move)
* Ventilate - observe, listen (stomach, lungs)
* Secure with tape
121
INFO CARD
Visual steps of LMA insertion.
122
Types of LMAs: Classic vs Supreme LMA
LMA supreme: modified cuff design, a drainage tube that allows for gastric access, and an integrated bite block
123
Additional SGA options
LMA fast-trach and I-Gel
124
Discuss the advantages of using an LMA
* Increased speed and ease of placement by inexperienced personnel
* Improved hemodynamic stability at induction and during emergence
* Reduced anesthetic requirements for airway tolerance
* Lower frequency of coughing during emergence
* Lower incidence of sore throats in adults (10% to 30%)
* Avoids "foreign body" in the trachea
125
Discuss the disadvantes of using an LMA
* NOT a definitive airway
* *Lower* seal pressure
* Higher frequency of gastric insufflation
* Esophageal reflux more likely
* _Inability_ to use mechanical ventialtion
* \*\*patient should be spontaneously breathing\*\*
* CANNOT use NMBD (neuromuscular blockade)
126
List the potential hazards to airway management.
* Dental damage
* Soft tissue/mechanical injury (i.e. bleeding)
* Laryngospasm
* Bronchospasm
* Vomiting/aspiration
* Hypoxemia/hypercarbia
* Esophageal/endobronchial intubation
* SNS stimulation
* *Intubating is the most stimulating stimulus you can do to the human body/more stimulating than surgery*
127
What is a "MAC" case?
**Monitored Anesthesia Care**
* Complete airway set up and ready to go
* Nasal cannula - EVERYONE GETS O2
* Spontaneously breathing patient
* Nasal airway if snoring (partially obstructed breathing)
128
General Anesthesia - Mask Case: When do we use?
* Difficult airway not present
* Surgeon does **not** need access to head/neck
* **No** airway bleeding/secretions
* Case of *short* duration
* No table position changes - head available
* Obstruction easily relieved with oral nasal airway/chin lift
* _Patient will spontaneously breathe_ - no neuromuscular blocker used
129
General Anesthesia - LMA Case: When do we use?
* Difficult airway **not** present
* Surgeon does **not** need access to head/neck
* _No_ airway bleeding/secretions
* Case of *short* duration
* More reliable patent airway than mask
* Want hands free
130
General Anesthesia - Tracheal Intubation: When do we use?
* Airway compromise
* Airway inaccessible
* *Long* surgical time
* Alternate surgical positions
* Surgery of head, neck, chest, or abdomen
* Need for controlled ventilation and/or PEEP
* Inability to maintain airway with mask/LMA
* Aspiration risk
* Airway/lung disease
* Surgery requiring NMBD/muscle relaxation
131
What parts of the upper airway are innervated by the trigeminal nerve?
* Branches of the trigeminal nerve innervate the nasal passages
* Hard and soft palate
* Anterior 2/3 of the tongue
132
What parts of the upper airway is innervated by the glossopharyngeal nerve?
* Posterior 1/3 tongue
* Soft palate (mostly uvula)
* Oropharynx
133
What/where is the valleculae?
Paired spaces bound by the glossoepiglottic folds (connection point of tongue and epiglottis in the oropharynx).
## Footnote
*(between epiglottis and tongue)*
134
What is the narrowest portion of the pediatric airway?
The cricoid cartilage
135
What is the narrowest portion of the adult airway?
The glottic opening
136
What are the intrinsic laryngeal muscles that control the opening and closing of the glottic opening?
* Lateral Cricoarytenoid
* Arytenoid muscles (oblique and transverse)
* Posterior Cricoarytenoid
137
What are the intrinsic laryngeal muscles that control vocal cord length?
* Cricothyroid
* Thyroarytenoid
* Vocalis
138
What muscles adduct the vocal cords?
The lateral cricoarytenoid and the arytenoid (oblique and transverse) muscles. *(intrinsic laryngeal muscles)*
139
What muscle(s) abduct the vocal cords?
The posterior cricoarytenoid muscle--an intrinsic laryngeal muscle
140
What intrinsic laryngeal muscle(s) tense/elongate the vocal cords?
Cricothyroid muscle
141
What intrinsic laryngeal muscle(s) relaxes/shortens the vocal cords?
The thyroarytenoid and vocalis muscles
142
What are the groups of the extrinsic laryngeal muscles that are responsible for moving the larynx as a whole?
* Suprahyoid group
* Infrahyoid group
143
What raises the larynx cephalad?
The suprahyoid group of the extrinsic laryngeal muscles
144
What moves the larynx caudad?
The infrahyoid group of the extrinsic laryngeal muscles
145
What are the main components of the upper airway?
* Nasal passages
* Oral cavity
* Pharynx
* Larynx
146
Which mainstem bronchus has a greater likelihood of foreign bodies or ETT's entering and why?
The right mainstem bronchus due to its branching off at a more vertical angle than the left mainstem bronchus
147
As part of your airway assessment, what are the different tests for oropharyngeal evaluation?
* Mallampati classification
* Thyromental distance
* Mandibular protrusion test
148
When performing the mallampati test, why do you not want the patient to say "AHH"?
This will cause the uvula to go up and give you false hope. So, you want the uvula in the resting position since that is how it will be when you induce anesthesia.
149
What mallampati classification is generally associated with an increase in difficulty for direct laryngoscopy?
III & IV
150
What is the mandibular protrusion test assessing?
The ability to do a good jaw thrust, which can help to move soft tissues in back of throat up and out of the way, making it easier for direct laryngoscopy.
151
What class(es) of the mandibular protrusion test is associated with difficult laryngoscopy?
B & C
152
The technique for mask ventilation is dependent on what two key elements?
* Maintenance of a seal between the face mask and the patient's face
* An unobstructed upper airway
153
What are the complications/precautions for an oral airway?
laryngospasm
bleeding
soft tissue dammage
154
What can happen if the oral airway is too large?
If too long, it can push down the epiglottis
155
Describe the scissors technique of mouth opening
The right thumb pushes caudally on the right lower molars while the index or third finger of the right hand pushes on the right upper molars in the opposite direction.
156
Gold standard for confirming ETT placement
Seeing 3 wave forms for etCO2
157
