Structure of the Airway Flashcards
How can you increase the size of the thorax? What does this do?
Contraction of the diaphragm (causing it to lower) and raising the ribs creates a negative intra-thoracic pressure which sucks air in through conductive passages. (Inhalation/inspiration)
How is exhalation/expiration achieved?
Decreasing the size of the thorax which is achieved by muscle relaxation. This doesn’t usually require energy.
What are nasal cavities lines by?
A highly vascularised mucosal membrane lined with Respiratory Epithelium (pseudostratified, ciliated, columnar, interspersed with goblet cells)
What is the nasal septum?
Midline structure made of cartilage and bone which seperates the left and right nasal cavities.
What can occur from a deviated septum?
Clinical issues, for example, sinus drainage may be compromised or a predispose to sinusitis.
What are the boundaries for the nasal cavities
Medial is the nasal septum
On the floor are hard and soft palates
On the roof is bone (ethmoid, frontonasal and sphenoid)
What do conchae/turbinates do and where are they found?
Found on the lateral walls of the nasal cavity. They provide turbulence, and increase the surface area for air flow and warming of air.
What is under/lateral to conchae/turbinates? and what is their function
Meatus. They have adjacent air sinuses which open up into the meati, communicating between the sinus and air cavity.
Name the fours nasal sinuses. What is their general function?
Maxillary, Ethmoidal, Sphenoidal and frontal. They assist in the warming of incoming air.
What drains tears to the nasal cavity?
Nasolacrimal
Why is the Nasal mucosal membrane a common area for epistaxis (nose bleeds)
It is highly vasularised with vessels that anastamose between branches of the external and internal carotids
Where are the nerves for sense of smell and the olfactory bulb located?
In the roof and upper parts of the lateral wall.
Name the three parts of the pharynx
1 - Nasopharynx
2 - Oropharynx
3 - Laryngopharynx
Name some of the features of the nasopharynx
It transports air and is divided from the oropharynx by soft palate.
Name some of the features of the oropharynx
It transports air, fluid and food. These must be separated to the air passes into the larynx while food and fluid passes into the laryngopharynx
What is the epiglottis?
It is a flap that prevents food and fluid from entering the lungs
What is the ary-epiglottis fold?
Muscles that close the epiglottis.
Changing the laryngeal diameters can allow what?
Passage of air only, control of airflow for speech and raising intra-abdominal pressure.
What are the different types of laryngeal cartilages?
From the top you have the epiglottic, then thyroid, then arytenoid (sitting on the very top of this are two peaks called corniculate cartilage) and then cricoid.
Name two sights that are used for an emergency airway
The cricothyroid membrane and three rings down the trachea.
What is the quadrangular membrane?
It is a membrane which is part of the ary-epiglottic fold. (seals off airway)
What is the vestibular fold?
It is formed by the lower edge of the quadrangular membrane and it aids the prevention of food and fluid entering the airway.
What is the vocal fold?
The vocal chords. They are found at the upper edge of the cricothyroid membrane.
What do the aryepiglottic folds form?
The laryngeal inlet, a protective sphincter. The muscles in the fold aid opening and closing of the laryngeal inlet . Closure of the inlet is by elevation of the larynx, occurs during swallowing.
Where is the saccule found and what is found there?
It is located in the opening of the laryngeal ventricle, there are mucosal glands which help lubricate the vocal folds.
What do the vocal folds control?
The laryngeal diameter for; speech, coughing, sneezing and raising intra-abdominal pressure which is vital in mictrurition (urinating), and lifiting heavy objects.
Muscles within or adjacent to the vocal folds control the?
Narorwing or widening of the rima glottidis (the opening of the vocal folds) or alter their tension.
What are the functions of the larynx muscles?
- Open and close the ary-epiglottic folds (laryngeal inlet)
- Close and open the rima glottidis
- Shorten and lengthen the vocal folds
What nerve supplies the one muscle and sensation above the vocal cords?
The superior laryngeal nerve.
What nerve supplies all other muscles and sensation below the vocal cords?
The recurrent laryngeal nerve
The trachea lies where?
Medial between the left and right carotid arteries and jugular veins, inferior to the larynx and anterior to oesophagus and the thyroid glands surrounds the upper portion.