The flashcards below were created by user
on FreezingBlue Flashcards.
Describe the anatomy of the larynx. Where does it lie? How many cartilages? Where does the blood supply come from?
- The larynx extends vertically from the tip of the epiglottis to the inferior border of the cricoid cartilage. It lies in the anterior neck, at the level of C3-C6 vertebrae, in the adult, C4-6 and child is C3-5. The laryngeal skeleton consists of 9 cartilages joined by ligaments and membranes. The blood supply the larynx: arterial supply comes from the subclavian
- artery to the inferior thyroid artery to the inferior laryngeal artery & then venous drainage to the inferior laryngeal vein from there to the brachial cephalic vein and from there to the SVC.
what are the cartilages of the larynx?
- 3 single cartilages: thyroid, cricoid
- & epiglottic
- 3 paired: arytenoids, corniculate, and
- the cuneiform.
- Hyoid bone is connected to but not part
- of the larynx.
What shields the cartilages of the larynx and the epiglottis?
- the thyroid cartilage shields the smaller
- cartilages of the larynx just as the hyoid bone shields the superior part of
- the epiglottis.
What is the largest of the laryngeal cartilages? What attaches the thyroid cartilage to the hyoid bone?
The thyroid cartilage is the largest of the laryngeal cartilages and the inferior 2/3 of the thyroid cartilage is that plate like laminae that fuse anteriorly and this is what forms the laryngeal prominence (aka Adams apple)The V shaped superior thyroid notch(thyroid notch) is above the laryngeal prominence. The thyrohyoidmembrane will attach to the superior horn of the posterior border of thethyroid cartilage. It attaches the thyroid cartilage to the hyoid bone.
Tell me about the cricoid cartilage? how does it articulate with the thyroid cartilage?
- The inferior horns of the thyroid
- cartilage then articulate w/the lateral surfaces of the cricoid cartilages.
- Cricoid cartilage is shaped like a signet
- ring, band facing anteriorly and is much smaller than thyroid cartilage but it is also thicker and stronger and only complete ring of cartilage to encircle any part of the airway, narrowest part of airway in pediatric patients.
How is The cricoid is attached to the thyroid cartilage?
- The cricoid is attached to the thyroid
- cartilage inferiorly by the median cricothyroid
- ligament. Attached to the 1st tracheal ring by the cricotracheal
- The cricothyroid ligament can be felt as the soft spot on the neck inferior to the thyroid
- cartilage, this is where the larynx is closest to skin and most accessible.
The epiglottic cartilage gives flexibility to the epiglottis which is a heart shaped cartilage covered w/mucus membrane, posterior to the root of tongue and hyoid bone andanterior to laryngeal inlet. The epiglottis functions to cover the glottis when swallowing to prevent food and liquids from getting into lungs when we’re eating. Epiglottis is the first cartilage seen on direct laryngoscopy.
- The arytenoid cartilages are
- pairs of 3 sided pyramid like structures. They sit on the cricoid, each one has
- an apex superiorly, a vocal cord process anteriorly, and a large muscular
- process that projects laterally from it’s base. The apex will bear the corniculate cartilage
what cartiage is on top of the arytenoids?
And the corniculate cartilages have been described as looking like party hats sitting on top of the arytenoids
where are the cuneiform cartilages?
The cuneiforms are elongated sitting a bit behind the corniculates on the base of the epiglottis.
The cricoarytenoid joints. What do they do?
- The cricoarytenoid joints are between the bases of the arytenoids and the superior lateral surfaces of the laminar of the cricoid cartilage. These permit the arytenoids
- to slide toward or away from one another to tilt anteriorly, posteriorly, and also to rotate. These movements are important to proximate, tensing, and relaxing the vocal cords.
the 3 single cartilages of the larynx?
The three paired?
Then from top to bottom, there’s the..........
- the 3 single cartilages of the larynx are
- thyroid, cricoid, and the epiglottis. The three paired are the arytenoid, the cuneiform, and the corniculate. Then from top to bottom, there’s the hyoid bone, the thyrohyoid membrane, the thyroid cartilage, the cricothryomembrane, the
- cricoid cartilage, the cricotracheal
- ligament and the 1st tracheal ring.
where is a tracy done?
trach is usually done midway between the thyroid notch and the suprasternal notch, through a vertical incision through the 2nd and 3rd tracheal rings with the thyroid (something) divided and retracted
The Rima glottis?
The Rima glottis is the opening between the vocal cords and this slide will show the variations in this opening that is associated with the normal physiology of the larynx. So the shape of the rima varies according to the position of the cords.
- •During ordinary breathing as you can see
- in A, the opening is narrow and wedge shaped.
- •With forced respiration in B, it’s wide
- and kite shaped,
- • during phonation (c) the vocal cords are
- closely approximated so the rima is slit like.
- •The voice will change in pitch according
- to the tension and length of the vocal cords, the width of the rima
- glottis and the intensity of the expiratory effort.
3 Functions of the larynx
The 3 functions of the larynx are protection of the airway, respiration, and vocalization.
- The protective function is by both reflex
- and involuntary processes primarily. The glottis closes by a reflex that gets activated when we swallow and it’s a basic primitive reflex that gets elicited by many different sensory stimuli that effect the superior laryngeal nerve.
Intrinsic and extrinsic muscles of the larynx?
•the muscles of the larynx are divided into the intrinsic and extrinsic routes.
•the Extrinsic Laryngeal muscles moves the larynx as a whole, there are 8 extrinsic muscles that get divided into 2 groups:
•Infrahyoid: depress hyoid and larynx
•Suprahyoid and Stylopharyngeal muscles: elevate hyoid and and larynx
- •Intrinsic muscles: move laryngeal parts, makes changes in length and tension of vocal chords. Essentially the opening of the glottis. They essentially have 3 functions: open vocal chores during inspiration, close vocal chords during swallowing, and changes
- tensions of vocal chords during speech.
•the intrinsic can be grouped according to their actions:
- •1.the adductors and abductors ( adductions toward midline, abduction away from
•3. the tensors
•4. the relaxors
- •want to star this, all but one of the intrinsic muscles is supplied by the recurrent
- laryngeal nerve.