Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Head, neck and introduction to neuroanatomy > Session 10 > Flashcards

Session 10 Flashcards

1
Q

What are the functions of the larynx?

A
  • Airway protection
  • Ventilation
  • Key role in cough reflex (rapidly expels anything inadvertently entering airway)
  • Role in production of sound
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Outline the location of the larynx in the body

A
  • Suspended from hyoid bone
  • Lies below hyoid bone
  • Begins at laryngeal inlet
  • Ends at lower border of cricoid cartilage (C6)
  • Continues as trachea
  • Sits in front of pharynx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which system is the larynx a part of?

A
  • Upper respiratory system
  • Transmits air in and out of lower respiratory tract
    DO NOT CONFUSE WITH PHARYNX (part of GI system)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What facilitates communication between the larynx, oropharynx and laryngopharynx?

A
  • Laryngeal inlet
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a piriform fossa?

A
  • Recesses
  • Part of laryngopharynx
  • Formed because pharynx hugs around the back of the larynx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Outline the framework of the larynx

A
  • Consists of series of cartilages and connective tissue membranes
  • Epiglottis (leaf-like cartilage)
  • Arytenoid cartilages - pyramid-shaped, sit on top of cricoid cartilage, swivel to allow action of vocal cords
  • Cricoid cartilage (only complete ring-shaped cartilage)
  • Thyroid cartilage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where are connective tissue membranes found in the pharynx?

A
  • Quadrangular sheet between arytenoid cartilage and epiglottis
  • Sheet of connective tissue between hyoid bone and thyroid cartilage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the relationship between the epiglottis and the thyroid cartilage?

A
  • Epiglottis connected by its stalk to inner surface of thyroid cartilage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What joints are found in the larynx?

A
  • Synovial joints
  • Thyroid-cricoid
  • Cricoid-arytenoid
  • Allows opening and closing of parts of larynx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What suspends the larynx from the hyoid bone?

A
  • Thyrohyoid membrane
  • Whenever hyoid bone moves, larynx also moves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which cartilages and membranes of the pharynx are palpable?

A
  • Hyoid bone
  • Laryngeal prominence
  • Cricothyroid membrane
  • Cricoid cartilage
  • 1st tracheal ring
  • Isthmus and lobes of thyroid gland
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a cricothyroidotomy?

A
  • Provides emergency access to airway beneath vocal cords
  • Done when patient cannot be intubated or ventilated
  • Temporary device inserted into airway via cricothyroid membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What makes up the laryngeal inlet?

A
  • Aryepiglottic folds x2 (upper free edges of quadrangular membrane)
  • Upper edge of epiglottis
  • Form oval-shaped opening of larynx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What creates the aryepiglottic fold?

A
  • Free upper border of quadrangular membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What creates the false vocal cord?

A
  • Free lower border of quadrangular membrane = vestibular ligament
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What creates the true vocal cord?

A
  • Free upper border of cricothyroid membrane = vocal ligament
  • Inserts into internal surface of thyroid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What lines the larynx?

A
  • Mucous membrane
  • Internal anatomy is shaped by folds formed by various ligaments/membranes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 3 regions of the larynx?

A
  • Supraglottis - epiglottis up to and including false cords
  • Glottis - narrowest part and includes true vocal cords until about 1 cm below
  • Infraglottis - below true vocal cords to inferior boundary of cricoid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What type of epithelium lines the larynx?

A
  • Pseudostratified ciliated columnar epithelium
  • Except true vocal cords, which are lined with stratified squamous epithelium (protects against abrasive forces of air)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is flexible nasoendoscopy?

A
  • Insert flexible endoscope via nasal cavity and pharynx to then visualise larynx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What should be seen on a laryngoscopic view?

A
  • Need to see vocal cord to ensure tube does not go through pharynx and oesophagus
  • Tip of laryngoscope is inserted in vallecula (space between back of tongue and epiglottis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the 2 main actions of the intrinsic laryngeal muscles?

A
  1. Alter size and shape of laryngeal inlet:
    - muscles within aryepiglottic folds can contract
    - narrow laryngeal inlet
    - flatten position of epiglottis
    - protects larynx during swallowing
  2. Alter tension in and position of true vocal cords
    - muscles within larynx alter position of arytenoid cartilages
    - vary position of vocal cords
    - adduction of vocal cords protects larynx during swallowing
    - enables phonation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What nerve supplies the intrinsic laryngeal muscles?

A
  • Recurrent laryngeal nerve of vagus nerve
  • Except for cricothyroid muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

When do we need to alter the size and shape of laryngeal inlet?

A
  • Direct food away from laryngeal inlet and into piriform fossae
  • When swallowing
  • Epiglottis is flattened
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Where are the vocal cords located?

A
  • Run from arytenoid cartilages to inner surface of thyroid cartilage at level of laryngeal prominence
26
Q

How is the position of the arytenoid cartilages altered?

A
  • Arytenoid cartilages move to alter position of vocal cords
  • Widens and narrows rima glottidis
  • Majority of muscles narrow rima glottidis by adducting vocal cords together
  • Only one muscle abducts vocal cords to widen rima glottidis
27
Q

What is the position of the vocal cords when breathing?

A
  • Abducted
  • Laryngeal inlet open
28
Q

What is the position of the vocal cords when swallowing?

A
  • Adducted
  • Laryngeal inlet also narrowed by muscles in aryepiglottic folds
29
Q

What is the position of the vocal cords during phonation?

A
  • Closely adducted but with a slight gap between them
  • Expired air forced through closely adducted vocal cords
  • Vibration of vocal cords creates sound waves
30
Q

What is the position of the vocal cords during a cough?

A
  • Vocal cords adduct and create a tight seal so no air escapes
  • Pressure builds until vocal cords snap open
  • Air is expelled
31
Q

How do the vocal cords change pitch?

A
  • High-pitched sounds = vocal cords taut
  • Low-pitched sounds = vocal cords less taut
  • Contraction of both cricothyroid muscles increases tension in vocal cords
  • Muscle located outside of larynx
32
Q

What is the action of the cricothyroid muscle?

A
  • Tilts thyroid cartilage forward on cricoid
  • Increases tension in vocal cords
  • Allows higher pitches to be reached
33
Q

Which nerve innervates the cricothyroid muscles?

A
  • External branch of superior laryngeal nerve (branch of CN X)
  • Closely related to superior thyroid artery
  • Risk of injury in thyroid surgery
  • Causes hoarseness of voice when attempting higher pitched sounds
34
Q

What happens to the epiglottis during swallowing?

A
  • Tongue pushes epiglottis posteriorly
  • Aryepiglottic muscles contract
  • Laryngeal inlet narrows
  • Epiglottis positioned horizontally
35
Q

Where is food directed towards on swallowing?

A
  • Directed over curved upper surface of epiglottis into piriform fossae of laryngopharynx
36
Q

What happens to the hyoid bone during swallowing?

A
  • Hyoid bone elevated and moved anteriorly
  • By suprahyoid muscles
  • Larynx moves and forward (away from pharynx, makes it more open for receiving food)
37
Q

What happens to the vocal cords during swallowing?

A
  • True vocal cords are adducted
  • Closure of rima glottidis
38
Q

What are the sensory and motor nerves that supply the larynx?

A
  • Sensory only to supraglottis and glottis = internal branch of superior laryngeal nerve
  • Motor only to cricothyroid muscle = external branch of superior laryngeal nerve
  • Recurrent laryngeal nerve supplies motor to intrinsic muscles and sensory to infraglottis
39
Q

Which artery does the superior laryngeal nerve run to?

A
  • Superior thyroid artery
40
Q

Outline the route of the right and left recurrent laryngeal nerves

A
  • Innervates all intrinsic muscles of larynx
  • Passes anteriorly to and then loops under right subclavian artery and arch of aorta on left
  • Ascends in tracheo-oesophageal (behind lobes of thyroid gland)
41
Q

Which nerve is at risk of damage during thyroid surgery?

A
  • Right and left recurrent laryngeal nerves
  • Close anatomical relationship with thyroid gland and inferior thyroid arteries
  • Results in paralysis of muscles moving a true vocal cord
42
Q

What can cause injury to the recurrent laryngeal nerve?

A
  • Disease or surgery involving larynx, oesophagus or thyroid
  • Aortic arch aneurysm (left RLN)
  • Cancer involving apex of lung (right RLN)
43
Q

What does a unilateral RLN lesion lead to?

A
  • Unilateral true vocal cord palsy
  • Hoarse voice
  • Ineffective cough
  • No significant impairment to airflow during breathing
44
Q

What happens to a vocal cord affected by a RLN injury?

A
  • Affected VC assumes a resting paramedian position
  • Paramedian = between fully abducted and fully adducted
45
Q

Why are bilateral RLN injuries so dangerous?

A
  • Both vocal cords assume a resting paramedian position
  • Bilateral RLN lesions are rare
  • Narrow rima glottis significantly
  • Significant airway obstruction
  • Emergency surgical airway needed
46
Q

What is laryngitis?

A
  • Inflammation of larynx often involving true vocal cords
  • Can have infectious cause or non-infectious
  • E.g. due to repetitive strain on voice
47
Q

How is laryngitis diagnosed?

A
  • Diagnosed clinically from history
  • Hoarse/weak voice and sore throat (oedema affects pliability vocal cords and increases their bulk)
  • History of URTI
  • Infectious and non-infectious aetiology
  • Usually self-limiting: fully resolves in 2-3 weeks
48
Q

Outline laryngeal nodules

A
  • Benign growth on vocal cords
  • Acute trauma or chronic irritation
  • Hoarseness of voice (>3 weeks)
  • Requires visualisation of cords +/- biopsy
49
Q

What is laryngeal oedema?

A
  • Due to allergic reaction or swallowed foreign body
  • Acute presentation
50
Q

What is epiglottitis?

A
  • Rare (more common in children)
  • Potentially airway threatening
  • Inflammation secondary to infection (usually Haemophilus Influenza type B)
  • Cellulitis of epiglottis and surrounding tissues
  • Child will be sitting forward in sniffing position, drooling, with stridor
  • Don’t upset the child, don’t place anything in the mouth
51
Q

What is croup?

A
  • Acute laryngotracheobronchitis
  • Barking cough
  • Inspiratory stridor
  • Classically caused by parainfluenza
  • Can be managed at home with steroids (reduce inflammation)
  • If stridor present at rest, give adrenaline/budesonide nebulisers and admit
52
Q

How do patients with a compromised upper airway present?

A
  • Stridor
  • Raised respiratory rate
  • Distress
  • Hypoxia
  • May or may not have cyanosis
53
Q

How is the airway maintained?

A
  • Actions and general tone in muscles of upper pharynx/larynx/tongue
  • Protective reflexes e.g. gag, cough, swallow
  • Complex neural pathways and reflexes involved to keep airway patent and safe
54
Q

What happens to the airway when a person is unconscious?

A
  • Decreased muscle tone
  • Suppression of reflexes
  • Airway at risk
  • Tissues can relax and fall back onto upper airway resulting in occlusion
55
Q

When do we need to manage a person’s airways?

A
  • Can be planned e.g. in preparation for surgery involving general anaesthetic
  • Can be emergency as there is an acute/immediate threat to airway e.g. laryngeal oedema/unconscious patient
56
Q

What simple manoeuvres can be done to manage the airways?

A
  • Head tilt
  • Chin lift
57
Q

When are airway adjuncts used?

A
  • If patient is breathing spontaneously
  • Can be oropharyngeal airway (Guedel) though this is contraindicated if minimal depression of consciousness (illicits gag reflex)
  • Or nasopharyngeal airway
58
Q

What are the pros and cons of airway adjuncts?

A
  • Allow for spontaneous ventilation
  • But offer no protection of lower respiratory tract from vomit/secretions
59
Q

What are the pros and cons of supraglottic airways?

A
  • E.g. iGel
  • Maintains airway and affords some protection
  • Minimal technical skills required to insert
  • Often first line in cardiac arrest
  • Not for long-term ventilation e.g. if in ITU
60
Q

How is a definitive airway inserted?

A
  • Endotracheal tube (oral cavity, oropharynx, pharynx, trachea)
  • Technical skill
  • Requires use of laryngoscope to visualize vocal cords
  • Secures and protects lower respiratory tracts from secretions/vomit
  • Patient anaesthetised prior to insertion

Head, neck and introduction to neuroanatomy (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions