pulmonary anatomy - exam 3 Flashcards
How much CO2 would you expect to be in the beginning of expiration?
none - anatomical dead space
When is expired CO2 highest during expiration?
at the end
why is expired CO2 sloped?
still passing deoxygenated blood the whole time (continuous blood flow) - averaged out at 40 mmHg
How do you calculate PCO2 after inspiration?
- calculate fraction of CO2 = 40/760 = 5.263%
- multiple by FRC (5.263% * 3L = 158 mL = between breaths)
- calc new volume in lungs = 3.35 L
- new concentration of CO2 (158/3.35 = 4.7%)
- new PCO2 = 4.7%*760 = 36 mmHg
What would an inverted slope of mixed expired CO2 mean?
late stage emphysema - small airway collapse, base collapses 1st, CO2 higher at base and lower at top compared to normal - CO2 higher at first bc base expired first
How is alveolar dead space calculated?
Bohr equation: arterial CO2 - end-tidal CO2
How would alveolar dead space impact end title CO2?
lower end-title CO2
What is the Bohr equation?
VDCO2/VT = (PaCO2 - PECO2)/PaCO2
end-title CO2 should equal ______ CO2 as long as there’s no _______
arterial, shunting
what is the total compliance equation?
1/compliance = 1/lung compliance + 1/chest wall compliance
are the lungs and chest wall in series or parallel?
series
what is the normal compliance at FRC of the chest wall? of the lung? total compliance?
0.2 L/cmH2O each
total = 0.1 L/cmH2O
the chest wall wants to recoil _____, while the lung wants to recoil ______
outwards
inwards
both outward recoil and inward recoil will determine _______ and ________
pleural pressure and lung volume
how does barrel chest occur in COPD?
loss of elastic recoil; chest recoils outward and more positive pleural pressure; inc lung volume
what is the pulmonary compliance at FRC?
compliance = ΔV/ΔP
0.5L/2.5 cmH2O = 0.2 L/cmH2O
ΔP = (-5) - (-7.5)= 2.5 = 2.5 cmH2O
What is the difference between lung volumes supine vs upright/standing?
Supine has dec FRC and ERV, inc IRV
What is the FiO2 of humidified air? Dry air?
19-20%, 21%
how much oxygen is in the lungs between breaths?
PAO2 = 100 mmHg/760 = 13.16% * 3L = 0.395 L O2
How long can you go without breathing?
a little less than 2 minutes
0.395 L O2 between breaths
use 250 mL/min
What are the differences between the R and L lungs?
R - larger, heavier, 3 lobes
L - taller, 2 lobes
what structure divides the lobes of the lungs?
fissures
What are the 2 fissures of the right lung called?
horizontal and oblique
What are the segments within the lobes of the lungs called?
Bronchopulmonary segments
How many bronchopulmonary segments are in the right lung? Left lung?
10 - R
8 - L
The connective tissue on the organ itself is the ______ pleura, while the connective tissue lining on the inside of the chest is the _____ pleura
visceral, parietal
What is the pocket of air in the pleural space called on the side of the diaphragm?
Costodiaphragmatic recess
The heart sits on the _______
central tendon
The ______ side of the diaphragm sits lower than the other side
left
Where is the diaphragm anchored in the spine?
L spine vertebral bodies
Which muscles when contracting pull the rib cage down during forced expiration?
rectus abdominis and internal intercostals
Which accessory muscles increase the diameter of the chest cavity during exercise and thus assist with inspiration?
scalene muscles (3)
sternocleidomastoid muscle
external intercostal muscles
Where does the sternocleidomastoid muscle attach?
mastoid process (bone behind the ear) and sternum (midline)
Where do the scalene muscles attach?
neck vertebrae and first 2 ribs
Which muscles help stabilize the position of the thorax? Where are they connected?
pec muscles - major and minor
shoulder blades (coracoid process) and top of ribcage
What are the 3 parts of the pharynx?
nasopharynx, oropharynx, laryngopharynx
The larynx attaches ______ to ______
the pharynx to the trachea
What kind of muscle is the tongue?
Striated skeletal muscles
What are the bony projections in the nose? What are their purposes?
conchae/turbinates (superior, middle, inferior)
purposes: porous for blood vessels, create turbulence with curves to help filter inspired air, smell sensors
What are the purposes of the nose?
heat and humidify inspired air
filter air
How much air is inspired through the nose?
1/2
Which bones do the conchae project from?
ethmoid bone - top two conchae (superior and middle)
maxillary bone - inferior concha
What is the ideal route for nasal intubation?
The floor of the nose along the inferior concha - more stable bones
The projection off of the ethmoid bone is the ________. It attaches to the connective tissue that separates the L/R hemispheres of the brain called ______
crista galli
- falx cerebri
The cranial nerve responsible for facial sensory function is the ______. What are the 3 divisions?
trigeminal nerve (CN 5) - ophthalmic, maxillary, mandibular
Smell sensors/olfactory neurons in the nose are routed through the _______
cribriform plate of the ethmoid bone
The _______ nerve innervates the nasopharynx
trigeminal
The _______ nerve innervates the back of the mouth/tongue, anterior to the epiglottis
glossopharyngeal (CN 9) - both somatic and taste
The _______ nerve innervates the oropharynx to the larynx and the trachea
vagus (CN 10)
Which nerve innervates the epiglottis?
vagus (CN 10)
Which cranial nerves are responsible for the front 2/3 of the tongue?
somatic - CN 5 (trigeminal) mandibular division (3)
taste - CN 7
What structure typically makes people snore?
soft palate
What are the 3 types of tonsils?
pharyngeal (behind soft palate), palatine (back of tongue), lingual (base of tongue)
Which tonsils if enlarged can restrict breathing?
pharyngeal
What are the 3 types of salivary glands?
sublingual (front), submandibular (rear), parotid (each side of face)
Which salivary gland gets engorged during the international slapping competition?
parotid gland
The topmost piece of cartilage of the larynx is the ________
epiglottis
What is the space called between the lingual tonsils and the epiglottis?
Valeculla - where you want to put the tip of the MAC blade
Which blade is best for repositioning large tongues?
MAC blade
When swallowing, how does the epiglottis cover the airway?
Epiglottis moves back and the larynx (voice box) moves up
The ______ bone attaches to muscles in the mouth and cartilage in the larynx
hyoid
The _____ cartilage is the largest piece fo cartilage in the larynx
thyroid - connects hyoid bone to trachea
Which cartilage is ringed in the trachea?
Cricoid
Which structure allows the thyroid cartilage to pivot down?
cricothyroid joint
The portion of the thyroid cartilage that connects to the cricothyroid joint is the ________
inferior horns (processes)
The sides of the thyroid cartilage where the thyroid sits is called the ______
laminae
Which portion of the thyroid cartilage connects to the hyoid bone?
superior horns
The technical term for the Adam’s apple is the ________
laryngeal prominence
Where are the vocal cords attached? How does the length of the vocal cords change the pitch of voice?
laryngeal prominence
- longer = deeper
The divots of the cricoid cartilage where the inferior horns of the thyroid cartilage sit are called the ______
articular facets for thyroid cartilage
The area of the cricoid cartilage where the vocal cords sit is called the ______
articular facets for arytenoid cartilage
The ________ cartilage attaches to the vocal cords. What shape are they?
arytenoid - diamond-shaped
The small appendage on the arytenoid cartilage is called the _______ cartilage
corniculate
What are the unpaired cartilages of the larynx?
thyroid and cricoid
What are the unpaired cartilages of the larynx?
arytenoid and corniculate
Which muscles are responsible for determining the tension of and how open/closed the vocal cords are?
laryngeal muscles
- cricothyroid muscle (external, pulls thyroid cartilage down/forward, tightening the vocal cords)
What is the most narrow part of the airway in patients under 10 yoa?
cricoid cartilage
What is the most narrow part of the airway in patients over 10 yoa?
transglottic space - space between vocal cords
What is a potential issue with using cricoid pressure?
goal is to prevent aspiration by occluding the esophagus, but the increased pressure can cause the esophageal sphincter to blow out, causing permanent damage
