Session 10 Flashcards
What are the functions of the larynx?
Preventing food/fluid entering the airway
Ventilation (air into lungs)
Phonation
Cough reflex if something inadvertent entering airways
What lies superiorly to the larynx?
What lies posteriorly?
How does it continue?
From where to where?
Hyoid bone (supra/infra hyoid)
As the trache
From laryngeal inlet to lower border of cricoid cartilage (C6)
Laryngopharynx
Role of larynx stalk?
Different cartilages making up the framework of larynx?
What splits tracheal rings? Relevance?
Attaches larynx to thyroid cartilage
Arytenoid
Cricoid
Thyroid
Cricothyroid ligament, in an emergency where patient can’t be ventilated due to swelling of vocal cords it provides access into airway (cricoidthyroidotomy).
What does the quadrangular membrane form?
Describe the two important ligaments on the larynx
What lies between these folds?
The folds split the larynx into what regions?
2 Aryepiglottic folds which form a laryngeal inlet
Vestibular ligament/fold (fixed)-free lower border of quadrangular membrane
Vocal ligament/fold (mobile)-free upper border of cricothyroid membrane
A small recess (ventricle) that moves up into a saccule containing the mucos glands that keep vocal folds moist.
Supraglottis, glottis, infraglottis
What lines the larynx?
What is used in intubation to view vocal cords?
How else can you get a good view of larynx?
Mucous membrane
Endotracheal tube in subglottic region
Flexible nasoendoscopy
Main two actions of laryngeal muscles?
Their role in swallowing?
In/exhalation?
Phonation and cough reflex?
How do the muscles cause this?
Size/shape of laryngeal inlet
Tension/position of vocal cords
Close inlet and vocal cords to protect resp tract
Open vocal cords thus inlet allowing flow. ABDUCTION.
ADDUCT/close vocal cords. Air forces through tight VC’s and sound waves are created.
They move arytenoids cartilage position to cricoid which determines position of vocal cords thus size of glottis.
What nerve supplies intrinsic muscles?
Describe process of coughing?
Vital for coughing and phonation?
Recurrent laryngeal nerve of vagus (right to right). Apart from cricothyroid muscles-branch of sup laryngeal nerve
VC’s Aduct after inspiration. Expiratory muscles contact so Intrathoracic pressure builds then suddenly abduct so explosive outflow.
VC’s meet at midline
What determines pitch of sound?
What can increase tension?
Where is this muscle found?
Innervated by?
Injury to nerve?
Near by artery?
Tension of VC’s.more taught=higher pitch.
Bilateral contraction of cricothyroid muscle, tilting thyroid cartilage forward onto cricoid.
Outside the larynx.
External branch of superior laryngeal nerve (branch of cnX)
Hoarseness of voice especially on high pitch.
Sup thyroid artery
How does the larynx close in swallowing?
Role of internal superior laryngeal nerve?
Suprahyoid moves bone up. Larynx moves up and anterior. tongue moves epiglottis posteriorly and aryepiglottic muslces contract narrowing inlet as epiglottis now more horizontal. Vocal cords are also closed.
Sensory for supraglottis and glottic thus VC’s
Path of Recurrent laryngeal?
Any sensory?
Why might it be injured in thyroid surgery?
Others potential threats?
Anteriorly then on the right loops under right subclavian artery and on left the Arch of the aorta.
Infraglottis
Close relationship with thyroid gland and inf thyroid arteries.
Aortic arch aneurysm or apex of lung on Right recurrent.
What happens in unilateral RLN injury?
Position of VC’s when paralysed?
Bilateral lesion?
Laryngitis?
Unilateral VC failure so hoarseness and ineffective cough. Contra lateral side can eventually compensate.
Paramediam position.
Very small glottis so surgery required.
Inflammation of vocal cords.
What forms the true vocal cords?
False?
The superior edge of the cricothyroid membrane
Inferior edge or quadrangular membrane
What lines true vocal cords?
Rest of larynx?
Stratified squamous epithelium
Pseudostratified ciliated columnar epithelium
