Quiz 1- Respiratory System Flashcards
2 goals the respiratory system achieves?
1- oxygenation
2- ventilation
Purpose of epiglottis
Positioned upright, covers the larynx to prevent food from entering trachea/lungs
What are conchae/ their purpose?
folds in nasal cavity that increase the surface area to warm
and humidify air to body temp/ 95% water vapor saturation
3 Functions of the nose
1- Warm & humidify air
2- Filter & obstruct foreign particles from entering lungs with nasal hair and ciliated epithelium
3- Assist phonation & sensation of smell (CN1)
Vallecula?
Space anterior to the epiglottis at root of tongue that the MAC blade slides into.
Pressure on hyoepiglottic ligament lifts epiglottis
Palatine Tonsils Location & Function
- b/l tonsils in pharynx
- Defense against infectious pathogens
What is Waldeyer’s Ring?
- Ring of Tonsils/lymphoid tissue in pharynx.
- includes palatine tonsil (what we normally think of tonsils) and lingual tonsil (at back of tongue)
MP Class 1
full uvula, tonsillar pillars, soft palate
MP Class 2
partial view uvula/tonsils, soft palate
MP Class 3
soft palate only
MP Class 4
hard palate only
Glossoptosis
collapse of oropharynx
macroglossia
large tongue
micrognathia
small jaw, mandible
prognathism
protrouding jaw, mandible
microgenia
small chin
microstomia
small mouth
malocclusion
upper protrusion (buck teeth)/ overbite
Location of larynx- adult
C3-6
Location of larynx- birth
C3-4
Normal atlas- occiput extension
35 degrees
5 Functions of Larynx
1- protective airway sphincter 2- seals off airway during swallow 3- supports vocal cords 4- modulates speech 5- provides autoPEEP
Rima glottidis
space between cords
What is the narrowest portion of the upper airway in adults?
Rima glottidis
What is the narrowest portion of the upper airway in children?
Cricoid cartilage until age 5
Cartilages of Larynx
9 Total:
3 Unpaired
Epiglottis
Thyroid
Cricoid
3 Paired:
Arytenoid
Corniculate
CuneiformPurpose of Hyoid bone
to suspend the larynx
Function of Arytenoids
Rotate to open and close vocal cords
Extrinsic muscles of larynx- where/function?
- They attach to bone or pharynx
- move larynx during swallowing
Intrinsic muscles of larynx- 2 functions
2 sets, different fx:
1- alter shape and size of larynx
2- move vocal cords
Larynx muscles that alter size and shape- names
Aryepiglottic
Thyroepiglottic
Oblique Arytenoid
Larynx muscles that move the vocal cords
Cricothyroid Thyroarytenoid Lateral Cricoarytenoid Posterior Cricoarytenoid Traverse Arytenoid Vocalis
What nerve innervates the muscles of the larynx?
Motor/Sensory?
Recurrent Laryngeal Nerve - motor for all EXCEPT Cricothyroid (external SLN)
Superior Laryngeal Nerve
- Internal SNL= Sensory to infraglottis
- External SNL= Motor to Cricothyroid muscle
What nerve innervates the cricothyroid muscle and what does it do?
Tenses vocal cords, innervated by the External Superior Laryngeal Nerve
What are the 3 compartments of the larynx?
Supraglottis Compartment: above cords -epiglottis -false vocal cords Glottis (ventricle): at cords -true vocal folds -rima glottidis -arytenoids Infraglottis Compartment: below cords -cricoid cartilage -trachea
What happens to the epiglottis and larynx during swallowing?
epiglottis moves down to cover glottis
larynx moves upward by muscles
epiglottis pressed downward by base of tongue
3 important laryngeal membranes?
1- Thyrohyoid membrane 2- Quadrangular Membrane 3- Cricothyroid Membrane** - inferior to true VC -emergency airway for cric
Where do the Recurrent Laryngeal Nerve and Superior Layrngeal Nerve stem from?
The Vagus Nerve branch (CNX)
What does stimulation to the RLN do?
abduction of vocal cords
What does damage to the RLN cause?
VC adduction
What structure does the left RLN pass?
Aortic arch
What are the 2 branches of the SLN and what do they do?
1- Internal SLN: sensory
2- External SLN: motor
What is the Sphenopalatine Ganglion and what does it innervate?
- middle division of CN V (trigeminal)
- nasal mucosa, superior pharynx, uvula, tonsils
What is the Glossopharyngeal nerve and what does it innervate?
- CN IX
- lingual back 1/3, pharyngeal, tonsillar nerves, (oral pharynx, supraglottic region)
What does the Internal branch of the Superior Lyrangeal Nerve innervate?
Where does this nerve stem from?
What happens when this nerve is stimulated?
Sensory nerve: mucous membrane of supraglottis and glottis
Stimulation causes laryngospasm- reflex to protect airway
Stems from CN X
What does the External branch of the Superior Lyrangeal Nerve innervate?
Where does this nerve stem from?
External SLN: motor innervation of cricothyroid muscle- tenses VC
Stems from CN X
What does the RLN innervate?
trachea below VC’s:
innervates muscles of the larynx that move the true VCs (except cricothyroid) and those that move the larynx itself
What makes up the glottis?
The vocal folds: 2 pairs of horizontal membrane folds
1- False vocal cords
- upper vestibular folds that close during swallowing
2- True vocal cords: produce vocal sound
-vocal ligament within, mobile elastic fibers
Direct Laryngoscopy (DL) Grade 1
full view of vocal cords, glottis
This is the only abductor muscle of the vocal cords
Posterior Cricoarytenoid
Innervated by RLN
Direct Laryngoscopy (DL) Grade 2
partial view of VC, arytenoid and corniculate cartilages
Direct Laryngoscopy (DL) Grade 3
only epiglottis
Direct Laryngoscopy (DL) Grade 4
only soft palate
VC abduction- muscles and nerves?
ONLY the Posterior Cricoarytenoid Muscle
via stimulation of the RLN
VC adduction- muscles and nerves?
Intrinsic muscles close & tense VCs:
Close- RLN via Intrinsic muscles
Tense- External SLN via cricothyroid muscle
How is sound produced via VCs? What is VC position?
1-air forced between closed cords- causes vibration
2- vibratory sound waves formed to words by upper airway movement
3- sound modification by upper airway structures (pharynx, oral cavity, tongue, lips)
How is pitch of VC sound determined?
By VC tension:
more tension= higher sound
less tension= lower sound
What is the cricoid cartilage?
Cartilage ring located below larynx and thyroid cartilage
Between cricothyroid membrane & trachea
What is a Sellick Maneuver?
- aka cricoid pressure
- Pressure on the cricoid posteriorly to close the esophagus
When do you use a Sellick Maneuver?
- during RSI, trauma, full stomach, GERD, obesity, pregnancy, gastroparesis (DM), SBO, pyloric stenosis, etc…
- prevent gastric regurgitation into trachea
- Aligns glottic opening during intubation
- Prevents ventilation of air into stomach
What are the 2 differences in upper airways between adults and children?
1- level and shape of larynx: adults: C3-6, cylinder children: C3-4, cone shape (why we use uncuffed ETT in peds) 2- narrowest portion of airway -adults= rima glottidis -children= cricoid ring
What is the level of the carina?
T5-7
25cm from teeth*
What is the trachea and where does it extend?
Flexible cylindrical tube supported by 20-25 C-shaped cartilages
extends from C6 to T5
Functions of the bronchial tree
- distribute air to alveoli
- warm & humidify air
- filter & transport particles from lungs, ciliated
As bronchial divisions occur, what happens to airway resistance?
Airway resistance decrease because the overall cross-sectional area increases (even though the airway diameter decreases with branching)
What is the purpose of conducting airways?
Ventilation, but NO perfusion as they do not participate in gas exchange
Anatomical Dead Space? How much % of each breath?
-A portion of each breath is wasted ventilation- 30%
What does an ETT reduce dead space to?
-ETT bypasses upper airway and reduces dead space to 100mL
Estimate of dead space
2cc’s/Kg
What is an acinus?
The gas exchange segment that includes all respiratory structures:
- respiratory bronchiole
- alveolar ducts & sacs
- alveoli
Where does gas exchange start to occur?
respiratory bronchiole
By what means does gas exchange occur?
simple diffusion allows gaseous exchange between airspace & pulmonary capillaries
What are PS-CC and where are they found?
Pseudostratified Ciliated Columnar Epithelium- found from larynx to bronchi (mucociliary elevator)
What does smoke do to PS-CC?
Stuns/disables them and disrupts mucociliary elevator)
What are goblet cells & 3 functions?
Cells that release mucous into the airway (mucous blanket)
- moisten inspired air
- prevent drying of airway
- traps particles
Where & what are Clara Cells? 2 functions?
Clara cells are located in bronchioles (which lack goblet cells) & produce a mucus-poor, watery proteinaceous material that combines with surfactant & mucus.
Functions:
- assist with cleaning small airways
- reduce surface tension in bronchioles
What are Type I Pneumocytes?
Squamous epithelial cell is
flat & thin designed to increase alveolar surface area to facilitate gas exchange
They control fluid movement between interstitium & airspace
What are Type II Pneumocytes?
Cuboidal cells that repair alveolar epithelium after injury & secrete surfactant
What is surfactant?
- Mix of proteins, phospholipids, & ions
- decreases cohesiveness of water molecules= reduces surface tension/ force necessary to inflate alveoli
- preventions alveolar collapse during expiraton
What type of alveolar cell is unable to regenerate self?
Type I pneumocyte, but Type II pneumocytes can regenerate as type I
