Pulmonary Physiology Flashcards
respiratory centers affect ___ & ____ of ventilation
rate
depth
respiratory centers are influenced by: (3)
higher brain centers
peripheral mechanorecptors
peripheral & central chemoreceptors
muscles of inspiration
diaphragm external intercostals SCM anterior serratus scaleni serratus posterior superior levator costarum
muscles of expiration
rectus abdominis external and internal obliques transverse abdominis internal intercostals serratus posterior inferior transversus thoracis pyramidal
all muscles of inspiration _____ rib cage, EXCEPT ____
lift
diaphragm
muscles that when contract INCREASE thoracic cage volume (by 3% of TBE)
muscles of inspiration
muscles that when contract PULL rib cage DOWN and DECREASE thoracic cage volume
muscles of expiration
under resting conditions, expiration is ______ and associated with the _____ of lungs
passive
recoil
3 types of pressure that are considerations for movement of air in/out of lungs
pleural pressure
alveolar pressure
transpulmonary pressure
NEGATIVE pressure btwn parietal and visceral pleural that keeps lung inflated against chest wall
pleural pressure
subatmospheric during INSPIRATION
supra-atmospheric during EXPIRATION
alveolar pressure
difference btwn alveolar and pleural pressure
measure of RECOIL tendency of lung
transpulmonary pressure
transpulmonary pressure peaks at _____ of _____
end of INSPIRATION
at onset of INSPIRATION, ____ pressure > _______, which is called ______
pleural pressure > lung volume
hysteresis
it is easier to inflate saline filled lung than air filled lung bc ________ forces have been _______ in saline filled lung
surface tension
eliminated
thoracic cage REDUCES compliance by _____ at the END of a normal ______
1/2
expiration
3 types of work of INSPIRATION
compliance work
tissue resistance work
airway resistance work
work required to expand lung against lung and chest forces
compliance (elastic) work
work required to overcome viscosity of chest wall and lung
tissue resistance work
_____% of TBE is used during normal quiet respiration
3-5
lungs have natural tendency to _____; surface tension forces are _____ cause and elastic fibers are _____ cause
collapse
2/3
1/3
_________ pressure keeps lungs against chest wall = “SUCTION”
Negative pleural pressure
if ____ pressure = ______ pressure, lung will COLLAPSE
pleural
atmospheric
causes of lung collapse
puncture of parietal pleural
erosion of visceral pleura (or blockage)
thin layer of mucoid fluid
pleural fluid
pleural fluid provides ____ & is considered a ______; excess is removed through _____
lubrication
transudate (ISF + protein)
lymphatics
collection of large amounts of free fluid in pleural space; edema of pleural cavity
pleural effusion
possible causes of pleural effusion
blockage of lymphatic drainage
cardiac failure-increased capillary filtration P
reduced plasma colloid osmotic P
infection/inflammation of pleural surfaces
reduces surface tension forces by forming a monomolecular layer btwn aqueous fluid lining alveoli and air, preventing a water-air interface
surfactant
surfactant is produced by ________ epithelial cells, specifically made of:
dipalmitoyl lecithin
surfactant apoproteins
Ca++ ions
type II alveolar epithelial cells
Surfactant OFFSETS the physical tendency of ______ alveoli having increased ______ pressure and would tend to empty into _______ alveoli
smaller
collapsed
larger
(“big get bigger, small get smaller”)
As the alveolar size ________, surfactant is concentrated which _____ surface tension forces, offsetting the _____ in ______
decreases
decreases
decrease
radius
__, ____ & ____ CANNOT be determined with basic spirometry, and instead use _____ method
RV
FRC
TLC
helium dilution method
___,____ & _____ DECREASE with restrictive lung conditions
VC
IRV
IC
___ generations of branching in lungs
BRONCHI have ___ generations
BRONCHIOLES have _____ generations
RESPIRATORY BRONCHIOLES have ______ generations
20
11
5
4
_______ give rise to alveolar sacs, which give rise to ______, 300 million with SA of ______
alveolar ducts
alveoli
50-100 m2
area where gas exchange cannot occur; 150 mL
*Calculated using pure O2 inspiration and measuring N in expired air
dead space
physiological dead space = ____ + ____
anatomical + non-functional alveoli
equation for alveolar volume
FRC- dead space
3 parts of EFFERENT ANS neuronal control of airways
SNS-beta receptors
parasympathetic -muscarine receptors
NANC nerves
SNS-beta receptors cause ______; DIRECT effect is _____; INDIRECT effect predominates via circulating ______
dilation
weak
epinephrine
parasympathetic-muscarine receptors cause
constriction
inhibitory NANC nerves release ___ and ___ –> ______
stimulatory –> _____ , mucous secretion, vascular ______, cough, vaso_____ and “neurogenic inflammation”
VIP and NO bronchoDILATION bronchiCONSTRICTION vascular HYPERpermeability vasoDILATION
-stretch receptors
-smooth muscle of proximal airways
are _____ nerves of ANS control of airways
afferent
in ANS control of airways, _____ contain neuropeptides, and are selectivity + by _____
c-fibers
capsaicin
local factors for ANS control of airways that cause DILATION
histamine –> H2
prostaglandins E series
local factors for ANS control of airways that cause CONSTRICTION
histamine –> H1
prostaglandins F series
smoke, dust, sulfur dioxide, acidic elements in smog are considered _____ and elicit constriction of airways mediated by ____ & ____
environmental pollution
parasympathetic reflex
local constrictor responses
normal level of HCO3 is ____; metabolic ACIDOSIS will cause ___ ventilation; metabolic _____ will cause ____ ventilation
organ that regulates is _____
24 mEq/L
+
-
kidney
normal level of CO2 is _____; respiratory ACIDOSIS will cause ____ ventilation; respiratory ALKALOSIS will cause _____ ventilation
organ that regulates is ____
40 mm Hg
+
-
lung
pulmonary artery wall is ____x as thick as aorta
RV is ____x as thick as LV
1/3
1/3
all pulmonary arteries have larger ______, which is more COMPLIANT, operates under _____ pressure and can accommodate ___ of SV from RV
- pulmonary veins are ____, but similar compliance compared to _____ veins
lumen lower pressure 2/3 shorter systemic
total pulmonic blood volume= ____ mL
-shifts have a ____ effect on pulmonary circulation
450
greater
supplies oxygenated blood to the supporting tissue and airways of the lung
-drainage is into exiguous or pulmonary veins
systemic bronchial arteries
only organ that receives blood flow in excess of cardiac output because it receives BOTH total pulmonic flow and some systemic flow simultaneously
lung
RV output + bronchial artery flow
total flow to the lungs
___ =100% of cardiac output, while ____ is only a SMALL % of systemic blood flow
right ventricular output
bronchial artery flow
