RE1: Chapter 23: Airway Management II Flashcards
Upper airway consists of
nose, mouth, pharynx, hypopharynx and larynx
Difficult ventilation is the inability of a trained anesthetist to maintain the O2 sat > _______% using a facemask for ventilation and ________FiO2 provided pre-op sats was w/in normal range.
92%
100%FiO2
The nose provides almost ______ of the resistance to breathing?
2/3
What 3 arteries supply blood to the nasal mucosa?
Maxillary (sphenopalatine),
Ophthalmic, &
Facial
Parasympathetic innervation to the nose arises from _______________ & _______________.
7th CN (Facial) and pterygopalatine ganglion
Sympathetic innervation to the nose is derived from ____________
superior cervical ganglion
At day _____, is the development of the pharyngeal arches.
22
6 arches develop from 5 structures (1-4 & 6 develop airway structures and 5 dissapears)
What separates the mouth from the nasal passages?
Hard and soft palate
The soft palate covers the posterior ____ to ____ of the oral cavity
1/3 to 2/3
The pharynx is divided into what 3 compartments?
Nasopharynx, oropharynx and hypopharynx
The nasopharynx lies anterior to ____
C1
The oropharynx lies anterior to ______. It is bounded superiorly by the ________ and inferiorly by the _______.
C2-C3
Soft palate
Epiglottis
The hypopharynx lies posterior to the larynx at ______ level. It is bounded superiorly by the _______ and inferiorly by the __________.
C5-C6
Epiglottis
Cricoid cartilage
What separates the upper and lower airway?
Cricoid cartilage
The larynx lies anterior to _______. It begins with the ______ and extends to the _______.
C3-C6 (Begins at C3-C4 & ends at the cricothyroid muscle at C6 in adults)
Epiglottis
Cricoid cartilage
The larynx is composed of three single cartilages and three paired cartilages. What are they?
Single
- Epiglottis
- Thyroid
- Cricoid
Paired
- Arytenoids
- Corniculates
- Cuniforms
What acts as a barrier to regurgitation in the conscious pt?
Cricopharyngeus muscle
What arises from the cricopharyngeus muscle?
Upper esophageal spincter
What is the role of the intrinsic muscles in the larynx?
Control tension of vocal cords and the opening and closing of the glottis
What does the posterior cricoarytenoid do?
Separates the vocal cords and opens the glottis (abducts)
What does the lateral cricoarytenoid muscles do?
Closes the cords (adducts)
“Lets Close Airway”
What does the cricothroid muscles do?
Tenses the vocal cords
What does the thyroarythenoid muscles do?
Relaxes the vocal cords
What nerves innervates all the muscles of the pharynx, larynx and soft palate?
Glossopharyngeal (afferent stimuli)
Vagus (efferent response - gag reflex)
Spinal accessory nerve
What two branches of the vagus nerve innervate the hypopharynx?
SLN and RLN
What does the SLN divide into?
Internal and external branches
What does the internal branch of the SLN provide?
Sensory innervation ABOVE the vocal cords
What does the external branch of the SLN provide?
Motor fnx to the CRICOTHYROID MUSCLE of the larynx
What does the RLN provide?
Sensory intervention BELOW the vocal cords
Motor intervention to all muscles of the larynx EXCEPT the cricothyroid muscle
Where does the right RLN travel?
Right RLN loops around the innominate artery
Where does the left RLN travel?
Left RLN loops around the aorta
What does unilateral injury to the RLN do? Bilateral injury?
Unilateral - hoarseness
Bilateral - Acute: respiratory distress or death
Chronic: develops comp. mechanisms, gruff/husky speech
What consists of the lower airway?
trachea, bronchi, bronchioles, terminal bronchioles, & resp bronchioles
What develops from the foregut and becomes the primitive lung bud?
Laryngotracheal groove