airway A&P Flashcards
what structures are included in the upper airway?
- nose
- mouth
- pharynx
- hypopharynx (laryngopharynx sometimes just called larynx)
- larynx
- vocal cords
- above cricoid
what structures are included in the lower airway?
- trachea
- bronchi
- bronchioles
- terminal bronchioles
- respiratory bronchioles
- alveoli
- below cricoid
what are the 3 sections of the pharynx?
- nasopharynx
- oropharynx
- hypopharynx
what is the location of the nasopharynx?
- C1 level
- skull to soft palate
what is the location of the oropharynx?
- C2-C3 level
- soft palate to epiglottis
what is the location of the hypopharynx?
- C5-C6 level
- epiglottis to cricoid
where is the larynx located?
- between levels C4, C5, C6
* usually higher in females
what makes up the larynx?
-9 cartilages (3 single and 3 paired)
describe the 3 single cartilages that are found in the larynx
- thyroid cartilage (adam’s apple)
- cricoid cartilage (forms a complete ring or signet ring; start of tracheal rings)
- epiglottis (protects airway from aspiration
what level is the cricoid cartilage usually found?
C6
describe the 3 paired cartilages found in the larynx
- corniculate cartilages (horn shaped)
- cuneiform cartilages (wedge shaped)
- arytenoid cartilages
what are the functions of the arytenoid cartilages?
attached to the abductor and adductor intrinsic muscles allowing anterior, posterior, and lateral vocal cord tissue movement
what are the 3 main functions of the larynx?
- protection of the lower airway
- facilitate respiration
- facilitate phonation
what makes up the anterior and lateral border of the upper airway?
thyroid cartilage
what makes up the posterior border?
posterior cricoid cartilage
describe the epiglottis
single, leaf-like cartilage above the glottis opening; closes during swallowing
where is the vallecula located?
area between the tongue and epiglottis
what is the function of the intrinsic muscles?
vocal cord tension, opening, and closing
what is the function of the extrinsic muscles?
- position
- phonation
- swallowing
describe the hyoid bone
- anchors and suspends larynx
- U shaped
- does not articulate with any other bone
- indirectly attaches to the styloid processes of the temporal bone via stylohyoid ligament
- indirectly attaches to the thyroid cartilage by the thyrohyoid membrane and muscle
- attached to intrinsic tongue muscles and pharyngeal constrictors
what are the laryngeal joints?
- cricothyroid joint
- cricoarytenoid joint
describe the cricothyroid joint and its function
- synovial joint
- articulation of inferior cornua of thyroid cartilage
- anterior/posterior sliding
- lengthens and tenses cords
- controls pitch
describe the cricoarytenoid joint and its function
- articulation between the base of the arytenoid cartilage and cricoid cartilage
- adducts and abducts the arytenoids while simultaneously rotating anterior and posterior
what common disease can affect airway joints?
any joint disease or progressive disease (rheumatoid arthritis)
- may present with raspy voice, hoarseness; joints may become inflamed and can narrow area between vocal cord ligaments leading to distress; changes airway anatomy
- know to suspect if affected fingers are noticed
what is the glottic opening?
- glottis: opening/inlet to trachea
- triangle in shape
what is the narrowest segment of the laryngeal opening in an adult?
glottis
what are the landmarks for finding the glottis?
- anterior landmark: vallecula
- posterior landmark: posterior aspect of arytenoid cartilage
what are the false vocal cords?
vestibular folds which are narrow bands of fibrous tissue on each side of the glottis
what are the true vocal cords?
pale, white ligament bands that attach to the thyroid anteriorly and the arytenoids posteriorly
describe the trachea
- C6, lower border of cricoid, to T5 carina
- 10-15 cm in length
- 16-20 horseshoe-shaped cartilage rings branching into the right and left bronchi at the 5th thoracic vertebra level
- *flattened posteriorly (rings open posteriorly)
- cross-section of the trachea is larger than the glottis opening
describe the main bronchi in comparison to each other
-Rt main bronchus has less of an angle (25 degrees) than the left main bronchus (45 degrees)…..this is usually why tube will migrate to rt main bronchus
what can shorten trachea?
- in between each ring, soft collapsible ligaments
- trendelenburg may cause trachea to shorten
what nerves innervate the airway structures for sensory?
- 3 branches of the trigeminal nerve
- glossopharyngeal nerve
- facial nerve
- internal branch of superior laryngeal nerve (SLN) (one of the two branches of the Vagus
what nerve innervates upper airway for motor?
recurrent laryngeal nerve (RLN)
what does the RLN innervate?
*all muscles of larynx except the cricothyroid muscle
what nerve innervate the cricothyroid?
-external branch of the SLN innervates cricothyroid muscle
describe the pharyngeal reflex
- posterior wall of pharynx is touched causing the gag reflex (suppression in Stage 3, age 1)
- gag reflex
describe laryngeal reflex
- touching or irritating mucosa results in a cough reflex
- suppression in Stages 3, plane 2
describe glottis closure reflex
-laryngeal closure, exaggeration of this is laryngospasm
what is the innervation and function of posterior cricoarytenoid muscle?
- opens (abducts) the glottis
- RLN
what is the innervation and function of the lateral cricoarytenoid muscles?
- closes the glottis (adducts)
- RLN
what is the innervation and function of the arytenoid muscles?
- closes (adducts) glottis, mainly posterior
- RLN
what is the innervation and function of the cricothyroid muscle?
- tension and elongation of cords (adducts)
- SLN (external branch)
what is the innervation and function of the thyroarytenoid muscles?
- relaxes/shortens vocal cords
- RLN
describe the laryngeal arterial supply
- branches of superior and inferior thyroid artery
- close proximity to RLN, which may be damaged during thyroidectomy
- superior laryngeal artery: internal surface of larynx
- cricothyroid artery: cricothyroid muscle
- inferior laryngeal artery: mucous membranes and laryngeal muscles
describe the laryngeal venous supply
-superior and inferior laryngeal vein
