Airway Anatomy Flashcards
(102 cards)
1
Q
What are the components of successful airway management?
A
requires in depth knowledge of the anatomy, physiology and pathophysiology of the airway
2
Q
What is imperative to successes in airway management?
A
Preparation
3
Q
What are some key components for successful airway management?
A
- Thorough assessment
- Diligent pre-planning and detailed knowledge of the difficult airway algorithm
- Technical skills that allow for adept use of airway adjuncts
4
Q
What are the divisions of the airway?
A
The airway can be divided into the upper and lower airways.
5
Q
What makes the upper airway?
A
Structures above the cricoid cartilage, including the nose, mouth, pharynx, hypopharynx and larynx
6
Q
What makes the lower airway?
A
Structures below the cricoid cartilage, including the trachea, bronchi, bronchioles, terminal bronchioles, respiratory bronchioles and alveoli
7
Q
Describe the structure of nasopharynx and oropharynx.
A
- The nasopharynx and oropharynx are the two passages into the airway
- The nasopharynx and oropharynx are initially separated by the hard and soft palate, but join together posteriorly
- The epiglottis is located at the base of the tongue
- The epiglottis separates the naso/oropharynx from the laryngopharynx (aka the hypopharynx)
- The vallecula is located between the base of the tongue and the anterior border of the epiglottis
8
Q
Define the pharynx.
A
Forms the common pathway for the respiratory and alimentary tracts. Divided into three components: nasopharynx, oropharynx, and hypopharynx.
9
Q
How long is the pharynx.
A
Approximately 12-16cm long in adults (extends from the skull to C6)
10
Q
Define the nasopharynx.
A
Bound superiorly by the base of the skill and inferiorly by the soft palate
11
Q
Define the oropharynx.
A
Bound superiorly by the soft palate and inferiorly by the epiglottis
12
Q
Define the hypopharynx.
A
Bound by the superior border of the epiglottis and the inferior border of the cricoid cartilage
13
Q
What is the characteristics of the larynx?
A
- Three Divisions
- Nine Cartilages (3 Paired, 3 Unpaired)
14
Q
Where does the larynx begin?
A
Begins with the epiglottis and extends to the cricoid cartilage
15
Q
What are the three divisions of the larynx?
A
Supraglottic, Glottic & Subglottic
16
Q
What are the characteristics of the supraglottic division (5)?
A
Epiglottis, ariepiglotic folds, arytenoid cartilages, false vocal cords, ventricle
17
Q
What are the glottic divisions?
A
Vocal cords
18
Q
Whare are the characteristics of the subglottic division?
A
Below the vocal cords to the inferior border of the cricoid cartilage
19
Q
Where do the vocal cords attach?
A
are attached to the thyroid cartilage at the anterior commisure
20
Q
Where do the vocal cords become mobile?
A
mobile as the vocal cords attach to the arytenoids
21
Q
What are the components of the unpaired cartilage (3)?
A
Thyroid, Cricoid, Epiglottis
22
Q
What is the only circumferential cartilage in the larynx?
A
Cricoid
23
Q
What are the components of the paired cartilage (3)?
A
Arytenoid, Corniculate, Cuneiform
24
Q
Where does the epiglottis attach?
A
Thyroid membrane
25
What happens when the epiglottis is elevated?
the vocal cords come into view
26
What are the functions of the epiglottis?
protect the airway
27
What is the vallecula?
is the depression between the epiglottis and root of the tongue
28
Where does the mac blade go during intubation?
vallecula
29
What are the characteristics of the thyroid?
- Adams apple
- Largest cartilage
- Anterior attachment of vocal cords
- V-shaped
30
What are the characteristic of the cricoid?
- Complete ring
- Narrowest part of a child’s airway*
- Selleck’s Maneuver (cricoid pressure) is applied here to prevent aspiration
31
What is the narrowest part of a child's airway (<5 years old) ?
Cricoid
32
What is the largest cartilage in adults?
Thyroid
33
What is the characteristics of arytenoid?
Tenses the vocal cords
34
What are the characteristics of corniculate (2)?
- Posterior part of aryepiglottic folds
| - Yellow elastic cartilage
35
What are the characteristics of cuneiform (2)?
Located on either side of aryepiglottic fold
| Small whitish elevation on mucous membrane
36
What is the narrowest part of the adult airway?
Vocal cords
37
What are the false cords?
Two thick ventricular folds next to true cords
38
What are the rima glottis?
The opening between the cords
39
What are the true cords?
Two strong bands of yellow elastic tissue
40
What is the cricothyroid membrane? Why is it important?
Cricothyroid membrane extends from the cricoid cartilage to the thyroid cartilage. Access to the airway may be accomplished by entering through this membrane. This structure is key for both entering the airway emergently, as well as for regional anesthesia of the airway
41
Where is the airway blood supply derived from?
branches of the carotid arteries, especially the thyroid artery
42
Where does the cricothyroid artery arise?
from the superior thyroid artery and crosses the upper cricothyroid membrane
43
Where does the superior thyroid artery line across?
Along the lateral edge of the cricothyroid membrane
44
What intervates the internal nose? What does this do for the tongue?
nasopalantine and nasociliary nerves- branches of the trigeminal (V)
also general sensory to tongue
45
What can Depression of the sympathetic nervous system (as w/ GA) cause to nasal tissues?
may cause engorgement of the nasal tissues increasing the likelihood of bleeding with manipulation
46
What does the facial nerve (VII) innervate (4)?
taste to anterior tongue (small amount sensory to oropharynx), parasympathetic to the nasal sinuses; salivary & lacrimal glands
47
What innervates the larynx (2)?
IX (Glossopharyngeal) & X (Vagus)
48
What does the CN IX (glossopharyngeal) innervate? (5)
- Posterior 2/3 of the tongue
- Roof of the pharynx
- Tonsils
- Undersurface of the soft palate
- Vallecula
49
What are the two components of the Vagus nerve (X)?
Superior Laryngeal Nerve
| & Recurrent/Inferior Laryngeal Nerve
50
What is the internal branch of the Superior Laryngeal Nerve innervate?
Sensory input to hypopharynx above the vocal cords
51
What is the external branch of the Superior Laryngeal Nerve innervate?
Motor function to the cricothyroid muscle of the larynx
52
What does the Recurrent/Inferior Laryngeal Nerve innervate?
- Sensory innervation to the subglottic area and the trachea
| - Motor function to all of the muscles of the larynx except the cricothyroid muscle
53
What type of innervation is occurring by the Recurrent/Inferior Laryngeal Nerve innervate?
Both motor and sensory
54
SLN and RLN innervate both the ________ and the _______
hypopharynx and the larynx
55
The right RLN recurs around the
| ____________________
brachiocephalic (innominate) artery
56
The left RLN loops around the _____
The left RLN loops around the aorta
57
What causes hoarseness or stridor during thoracic surgery?
Traction on either of these structures during thoracic surgery can cause injury to the RLN, causing hoarseness or stridor.
58
What can happen in the acute phase of bilateral injury to the RLN?
In the acute phase of b/l injury to the RLN, unopposed tension and adduction of the vocal cords result in stridor, which may deteriorate into severe respiratory distress and possibly death.
59
Patients with chronic RLN injury develop ____________.
compensatory mechanisms.
60
Injury to the SLN does not usually cause ____________.
respiratory distress.
61
What is the most common damage after subtotal thyroidectomy?
Unilateral recurrent laryngeal nerve damage
62
What is the common sign/symptom of Unilateral recurrent laryngeal nerve damage?
Hoarseness
63
What is the position of the Unilateral recurrent laryngeal nerve damage?
Cord maintains midway position
64
What is the position of the each cord with (Acute) Bilateral recurrent laryngeal nerve damage?
Each cord assumes midway position, Cords prone to close and obstruct during inspiration
65
(Acute) Bilateral recurrent laryngeal nerve damage: unopposed adduction leads to _______
stridor
66
What is another symptom of (Acute) Bilateral recurrent laryngeal nerve damage?
Aphonia
67
What is the treatment for (Acute) Bilateral recurrent laryngeal nerve damage?
Intubation
68
What muscle is involved in respiration?
Posterior cricoarytenoids
| recurrent laryngeal n.
69
What is the main function of the Posterior cricoarytenoids
| (recurrent laryngeal n.)?
Abduction of vocal cords
70
What is the muscles involved for phonation?
Lateral cricoarytenoids, Lateral thyroarytenoids, Medial cricoarytenoids, Cricothyroids
(external of sup. laryngeal), Vocalis
71
What is the main function of the Lateral cricoarytenoids?
Adduction of vocal cords
72
What is the main function of the Lateral thyroarytenoids?
Shortening and adduction of vocal cords
73
What is the main function of the Medial cricoarytenoids?
Shortening of vocal cords
74
What is the main function of the Cricothyroids
| (external of sup. laryngeal)?
Lengthening and increasing tension of vocal cords (tensor muscle of larynx)
75
What is the main function of the vocalis?
Tense and thicken the vocal cords
76
What are the muscles involved in sphincteric function?
Interarytenoid & Arytenoepiglottics
77
What is the main function of the Interarytenoid?
Closing of posterior commissure of the glottis
78
What is the main function of the Arytenoepiglottics?
Closing of laryngeal vestibule
79
Which muscle would be implicated in larygospasm (adduction)?
lateral cricoarytenoid and the lateral thyroarytenoid
80
What are the major cranial nerves that make up the nasal anatomy?
CN I (Olfactory), V (Maxillary and ophthalmic branches of trigeminal nerve) , VII (Facial (parasympathetic lacrimal and sinus functions)
81
What are the main structures of the nose? (3)
Bones, Cartilage covered by skin & Lined by mucous membrane
82
What divides the nose?
septal cartilage
83
What are some components of the nose?
Right and left nares, Turbinates and Sinuses
84
What is important component of the turbinates?
Very vascular
85
What is important component of the sinuses?
Ciliation begins
86
Deviated septum occurs in ______ population (trauma related)
75%
87
Why is a sniff test important for nasal intubation?
Deviated septum occurs in 75% population (trauma related), one side is bigger then the other
88
What components of the nose help to Humidifies and warms inspired air?
Turbinates and sinuses
89
What are the main functions of the nasal cavity?
-Primary orifice for air entry
-Vocal resonance
-Olfactory sense (CN I)
-Barrier against bacteria
(Cilia)
90
The nose is responsible for _______ of airway resistance
2/3
91
Why can issues occur with the nose? What may this require?
Vascular: issues with anesthesia/epitaxis (nasal intubations, nasal airways, NGT, anticoagulation, etc.) - may require ENT consults
92
What is a technique to assist with nasal intubation?
Lub the tube and warm the plastic tube with sterile NS- plastic warmed makses it more movable
93
What is an important characteristics of the nasal vascular supply?
Some arteries communicate with the frontal lobe of the brain (sinus infection pathway to the brain)
94
Pediatric Airway: What head anatomical characteristics of the head is found in the pediatric patients?
Large occiput
95
Pediatric Airway: Obligate _____ breathers
nasal
96
Pediatric Airway: What anatomical characteristics of the mouth is found in the pediatric patients?
Large tongue
97
Pediatric Airway: What anatomical characteristics of the vocal cords is found in the pediatric patients?
Anteriorly angled
98
Pediatric Airway: What anatomical characteristics of the epiglottis is found in the pediatric patients?
shaped differently – longer, narrower and stiffer
99
Pediatric Airway: What anatomical characteristics of the larynx is found in the pediatric patients?
Funnel shaped larynx that is proportionally smaller
100
Where is the larynx located in infants?
C3-C5
101
Where is the larynx located in adults?
C4-C6
102
What are two disorders associated with pediatric difficult airways?
Pierre-Robin Sequence & Goldenhar’s Syndrome
