Larynx and Thyroid Gland Flashcards
What vertebrae does the larynx extend from
from the 4th, 5th and 6th vertebra
What is the larynx attached to superiorly and inferiorly
- Superiorly it is attached to Hyoid Bone and opens into the laryngopharynx
- Inferiorly it is continuous with trachea.
What are the functions of the larynx
- Provides a patent airway
- Routes air and food into proper channels
- Voice production
Name the cartilages of the larynx
– Hyaline cartilage except for the epiglottis
– Thyroid cartilage with laryngeal prominence (Adam’s apple)
– Ring-shaped cricoid cartilage
– Paired arytenoid, cuneiform, and corniculate
cartilages
Which cartilage of the larynx is the largest
Thyroid Cartilage
Describe the thyroid cartilage and what structure it forms in the larynx
2 rectangular lamina fuses in the midline (thyroid notch)
Forms the adam’s apple
What is the strongest cartilage of the larynx
Cricoid
Describe the location of the cricoid cartilage in the larynx
Immediately below the thyroid cartilage.
Joins the first tracheal ring inferiorly.
Describe the shape of the cricoid cartilage
Ring shaped - only laryngeal cartilage to completely encircle airway
What structure articulates the arytenoid cartilage with the cricoid cartilage
The cricoarytenoid joint
Which cartilage has processes for the attachment of vocal cords
Arytenoid
Which laryngeal cartilages are probs for structural support
Cuneiform and Corniculate
Describe the shape of the epiglottis and state its function
Leaf shaped (fibrocartilage) Prevents aspiration during swallowing
What is a cricothyrotomy
An incision made through the skin and cricothyroid membrane to establish a patent airway during certain life-threatening situations, such as airway obstruction by a foreign body, angioedema, or massive facial trauma.
Describe the features of the Thyroid gland
Largest Endocrine gland
Lobes are cone shaped (pear shaped)
Highly vascular
What are the functions of the thyroid gland
- Produce thyroid hormones (TH)
- Vital for growth & metabolism - Iodine storage
- Essential for T3/T4 syntheses
What are the functions of the T3/T4 hormones
Increased metabolic rate
Increased protein synthesis
Increased energy production
Most important hormone in regulation of metabolic rate
What stimulates the release of T3/T4 from the thyroid gland
Decreased metabolic rate
What are the functions of the thyroid hormone calcitonin
Decreased blood calcium concentration
Decrease in the reabsorption of Ca and Ph from bones to blood
Calcitonin “tones” down serum Ca levels
What stimulates calcitonin release
Increased blood Ca levels
What are the general effects of the thyroid hormones on the cardiovascular system
- Increase heart rate
- Increase force of cardiac contractions
- Increase Cardiac output
What is the general effect of the thyroid hormones on oxygen carrying capacity
• Increase oxygen dissociation from hemoglobin
What is the general effect of the thyroid hormones on the intermediary metabolism
- Increase glucose absorption from the GI tract
* Increase carbohydrate, lipid and protein turnover
What are the general effects of the thyroid hormones on the nervous system
- Critical for normal CNS neuronal development
- Enhances wakefulness and alertness
- Enhances memory and learning capacity
- Required for normal emotional tone
Describe the location of the thyroid gland
anterior and lateral to the larynx and trachea. base is located at the 4th/5th tracheal cartilages
What are the lobes of the thyroid gland connected by
An isthmus that crosses tracheal cartilages 2-4
How many parathyroid glands are there
Usually four on the thyroid glands, two on each side
Where on the thyroid gland can parathyroid glands be found
posterior surface, can be embedded the thyroid gland
What is the role of the parathyroid glands
regulate calcium/phosphate levels
Where are the lobes of the thyroid gland attached
- Attached to cricoid cartilage by ligaments
2. Medial surface adapted to larynx and trachea
What supplies blood to the thyroid gland
- Highly vascular gland supplied by four large arteries a. R & L inferior thyroid artery
b. R & L superior thyroid artery
