Term
|
Definition
gas exchange
phonation
pulmonary defense
blood filter
acid-base balance
substrate conversion |
|
|
Term
|
Definition
trachea, bronchi, bronchioles, terminal bronchioles (generations 0-16)
anatomic dead space
receives blood from bronchial arteries
functions to condition air and has mucociliary escalator |
|
|
Term
|
Definition
respiratory bronchiole, alveolar duct, alveolar sac alveoli (generations 17-23)
receive blood from pulmonary circulation
functions as gas exchange location
surface area is huge
silent zone |
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Term
|
Definition
| respiratory unit including respiratory bronchioles and all of its divisions |
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|
Term
|
Definition
size > 5um, large
swallowed after being caught in mucus |
|
|
Term
| particles in bronchi/airways |
|
Definition
size 1-5um, medium
trapped in mucus and transported via synchronous beating of cilia to esophagus to be swallowed |
|
|
Term
|
Definition
size <0.1um
macrophages engulf and degrade and deliver to lymphatics |
|
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Term
|
Definition
aka radial traction
stabilizes alveoli by interconnectedness
if alveolus in center begins to collapse --> increases in wall stress of adjacent alveoli, which then tend to hold the collapsing one open |
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Term
|
Definition
P(A)-P(pl) = pressure of alveolus - pressure of intrapleural space
determines volumes of inspirationa nd expiration and is affected by pathological states |
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|
Term
|
Definition
rupture/puncture of chest wall causes air flow into pleural space
P(pl) equalizes with atmospheric --> lung collapses, mediastinum shifts, chest wall expands
tx: chest tube, seal, suck air, re-establish negative pressure around lung, lung reinflates |
|
|
Term
| functional residual capacity |
|
Definition
set by chest wall expansion and lung recoil balancing
volume in lungs after normal expiration
~2.5L
measure with He dilution technique or body plethysmography |
|
|
Term
|
Definition
end volume after biggest inhalation possible
~6L |
|
|
Term
| expiratory reserve volume |
|
Definition
maximal volume of air that can be exhaled from the end-expiratory position
~1.2L |
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Term
|
Definition
volume of air that subject can move in and out of lungs (TLC-RV)
~4.8L |
|
|
Term
|
Definition
volume of air remaining in the lungs after a maximal exhalation
~1.2L |
|
|
Term
|
Definition
total volume of air that can be inhale
~3.6L |
|
|
Term
| inspiratory reserve volume |
|
Definition
volume of air that can be inhale above normal tidal volume
~3.1L |
|
|
Term
|
Definition
normal volume of air move in and out in resting breathing
~0.5L |
|
|
Term
| standing: effects on lung volumes |
|
Definition
increase FRC and ERV; decrease IRV and IC
b/c diaphragm has lower resting position |
|
|
Term
| supine: effects on lung volumes |
|
Definition
decrease FRC and ERV; increase IRV and IC
b/c diaphragm has higher resting position |
|
|
Term
|
Definition
meaures anatomic dead space
involves 100% gas inhalatin and monitor of N2 exhaled
midpoint of N2 rise gives volume of dead space |
|
|
Term
|
Definition
| air that is brought into lungs but is not exposed to blood for gas exchange |
|
|
Term
|
Definition
used to measure physiologic dead space
based on CO2 only coming from gases being exchange at alveoli
normal ~165mL
VD/VT = [P(A)CO2-P(E)]CO2/P(A)CO2 |
|
|
Term
|
Definition
| anatomic dead space + wasted ventilation volume |
|
|
Term
|
Definition
physiolgocical condition (exercise, body position)
size of human (dead space volumes)
gender
age
disease states |
|
|
Term
| restrictive disease characteristics |
|
Definition
trouble getting air into lungs
ventilation movements are compromised by pulmonary, chest wall or diaphragmatic pathologies
decreased TLC, higher FEV1/FVC
x-ray: hypoinflated lungs, small contracted lungs, raised diaphragm
lung elastic recoil is overtaking chest expansion |
|
|
Term
|
Definition
interstitial lung disease
pulmonary edema
pneumonia
sarcoidosis
pleuritis
neuromuscular disease
thoracic cage defects
obesity |
|
|
Term
| obstructive disease characteristics |
|
Definition
trouble getting air out of lungs
increases RV and TLC, lower FEV1/FVC
ice-cream scoop Q-V curve
x-ray: hyperinflated lungs, lower level of diaphragm, mediastinum flattened
chest expansion is overtaking lung elastic recoil |
|
|
Term
|
Definition
| COPD, asthma, obliterative bronchiolitis, bronchiectasis, cystic fibrosis, upper airway obstruction, chronic bronchitis, emphysema |
|
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Term
|
Definition
| total volume of expired air in forced expiration |
|
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Term
|
Definition
| volume of air expired in first second of forced expiration |
|
|
Term
|
Definition
forced mid-expiratory flow rate, found using slope of FEV vs. time curve
normal is 4-5L/sec |
|
|
Term
|
Definition
volume of air expired in first second of forced expiration expressed as % of total volume expelled in forced expiration
normal 78-83% |
|
|
Term
| pulmonary artery, normal gas values |
|
Definition
|
|
Term
| alveoli, normal gas values |
|
Definition
|
|
Term
| respiratory airways, normal gas values |
|
Definition
|
|
Term
| pulmonary veins, normal gas values |
|
Definition
|
|
Term
|
Definition
ease with which an obeject can be deformed
distensibility
C = V/P
normal 200ml/cmH2O |
|
|
Term
|
Definition
| lung volume, lung size, elasticity/fibrosis of tissues, alveolar surface tension |
|
|
Term
| lung compliance decreases with |
|
Definition
high lung volume
fibrotic disease
alveolar edema that dilutes surfactant
vascular congestion |
|
|
Term
| lung compliance increases with |
|
Definition
low lung volumes
destruction of elastic tissue (emphysema)
more surfact, lower surface-tension |
|
|
Term
|
Definition
opposition of an object to deformation
inverse of compliance
E = P/V = 1/C |
|
|
Term
| airway resistance factors |
|
Definition
| airway size, smooth muscle tone, gas density, and dynamic compression |
|
|
Term
| dilation of airway smooth muscle |
|
Definition
sympathetics, epinephrine, beta-2 receptors
nitric oxide
increased PCO2 and decrease PO2 in small airways |
|
|
Term
| constriction of airway smooth muscle |
|
Definition
parasympathetics, ACh
histamines, leukotrienes, thromboxane A2
norepinephrine, alpha-receptors
decrease in PCO2 in small airways |
|
|
Term
| gas density + airway resistance |
|
Definition
| high gas density --> tubulence --> increase resistance |
|
|
Term
| effort dependent expiration |
|
Definition
| airflow determined by degree of effort subject makes during expiration |
|
|
Term
| effort independent expiration |
|
Definition
| airflow determined by degree of pulmonary elastic recoil and dynamic compression of airway |
|
|
Term
highest airflow resistance
lowest airflow resistance |
|
Definition
highest = medium bronchi
lowest = alveoli |
|
|
Term
|
Definition
inflation of lung follows a different curve than deflation of lung on V-P loop
due to variability in surface tension during breathing cycle |
|
|
Term
|
Definition
obstructive disease
loss of alveolar interdependence
increases TLC, FRC and compliance
lung is easily distended like a floppy balloon |
|
|
Term
|
Definition
restrictive disease
thickened alveolar membrane
decreases TLC, FRC and compliance
need higher pressures to reach certain volumes |
|
|
Term
|
Definition
diseases that increase resistance or decrease compliance force PT to use accessory muscles
dramatically increases oxygen cost of breathing
decreases efficiency of breathing |
|
|
Term
|
Definition
special phospholipids produced by Type II alveolar cells
acts to decrease surface tension on alveoli during inspiration
stabilizes lung by giving alveoli variability in surface tension
minimizes intrapleural pressure needed for inspiration |
|
|
Term
|
Definition
stabilize and prevent collapse of alveoli
decreases muscular effort needed to expand lungs by increasing compliance during inspiration
plays a role in host defense |
|
|
Term
| respiratory distress syndrome |
|
Definition
deficiency of amount or function of surfactant
shifts VP curve right, need higher P to get to set V
stabilization of alveoli lost, atelectasis
more work required through contraction of muscle to breath |
|
|
Term
|
Definition
| total pressure in gas mix is equal to sum of partial pressures of all the gases in mix |
|
|
Term
| total (minute) ventilation |
|
Definition
tidal volume x respiration rate
~7500 ml/min normally |
|
|
Term
|
Definition
(tidal volume - anatomic dead space) x respiration rate
~5250ml/min normally
measures air actually capable of gas exchange
measured by PaCO2 = VCO2/VA |
|
|
Term
|
Definition
measure of alveolar ventilation
if high, due to decreased VA, from hypoventilation
if low, due to increased VA, from hyperventilation |
|
|
Term
| why is P(A)O2 lower than P(atm)O2 |
|
Definition
saturation in water
dilution of % with FRC
continuous uptake of air |
|
|
Term
|
Definition
P(A)O2 = P(I)O2-P(a)CO2/RQ
= [P(atm)-P(H2O)]*%O2-VCO2/VA/RQ
normal ~100mmHg |
|
|
Term
|
Definition
|
|
Term
|
Definition
commonly used to identify defect in pulmonary gas exchange
normal 12-15mmHg |
|
|
Term
|
Definition
arises from aorta and intercostal arteries
perfuses to level of terminal bronchioles
venous drainage to azygous and hemiazygous and some to pulmonary veins (normal R-L shunt) |
|
|
Term
|
Definition
pulmonary flow = cardiac output
total blood volume ~500ml (serves to buffer changes in LV filling with changes in VR) |
|
|
Term
|
Definition
smallest cardiac veins
minute valveless veins in walls of heart that empty to many areas of heart including left heart |
|
|
Term
| normal right-left shunting |
|
Definition
venous admixture from bronchial and thesbian drainage
decreases PO2 and O2 content of blood |
|
|
Term
|
Definition
no affect on arterial Po2
increase venous PO2
less common than R-L, usually due to congenital abnormality |
|
|
Term
| pulmonary circulation characteristics |
|
Definition
| thinner walled vessels, greater diameter vessels, more distensible vessels, lower intravascular pressures, less work for RV |
|
|
Term
| pulmonary vascular resistance |
|
Definition
= [PAP-LAP]/PulmFlow = [PAP-LAP]/CO
normally ~2mmHg |
|
|
Term
|
Definition
| lung volume, right ventricular output, gravity, alveolar hypoxia, vasoactive factors |
|
|
Term
| lung volume: effect on PVR |
|
Definition
PVR is lowest at FRC
significant effect on lung volumes
TLc and RV have super high PVR |
|
|
Term
|
Definition
| increase PAP from increased pulmonary blood flow causes vessels to reach threshold of opening pressure and opens more vessels for perfusion |
|
|
Term
|
Definition
| increase in PAP from increased pulmonary flow increases the transmural pressure of vessels, causes increase in diameter of vessels |
|
|
Term
| alveolar hypoxia: effect on PVR |
|
Definition
P(A)O2 primary active regulator of PVR
smooth muscles are bathed in this O2
decrease in P(A)O2 --> constriction (avoids sending blood to poorly ventilated areas) |
|
|
Term
| vasodilators in pulmonary vessels |
|
Definition
| ACh, PGE2, PGI2, bradykinin, nitric oxide |
|
|
Term
| vasoconstrictors in pulmonary vessels |
|
Definition
| serotonin, histamine, norepinephrine, thromboxane, antiotensin II, alveolar hypercapnia, low pH mixed venous blood |
|
|
Term
|
Definition
PA > Pa > Pv
physiological dead space
normally little to none in healthy PT
potential increase with hemorrhage or general anesthesia |
|
|
Term
|
Definition
Pa > PA > Pv
usually upper 1/3rd of lung
potential increase with hemorrhage or general anesthesia |
|
|
Term
|
Definition
Pa > Pv > PA
usually lower 2/3rd of lung
increased transmural pressure in veins due to gravity effect
increase in exercise/exertion |
|
|
Term
| Henry's Law of Dissolved Gas |
|
Definition
| concentration of gas dissolved in liquid is proportional to partial pressure of gas in liquid |
|
|
Term
|
Definition
occurs when decrease in pH (increase in [H+] and PCO2)
decreases Hb affinity for O2 |
|
|
Term
decreased affinity of Hb for O2
(cause, effect) |
|
Definition
causes: Bohr effect, increase in temperature, increase in 2,3 DPG
effects: increase P50, good for delivery to tissues, right shift of dissociation curve |
|
|
Term
increased affinity of Hb for O2
(cause, effect) |
|
Definition
causes: decrease [H+] or PCO2, increase pH, decrease temperature, decrease 2,3DPG
effects: decrease P50, good for pickup in lungs, left shift of dissociation curve |
|
|
Term
|
Definition
= [Hb gm*1.34ml/gm*%sat]+[PO2*0.003]
Hb amount in blood has greater influence on content that PO2 |
|
|
Term
|
Definition
decreases HB, decreases O2 conetent, decrease PvO2
PaO2 remains same
does not effect Hb(sat) vs. PO2 curve |
|
|
Term
|
Definition
huge, rapid decrease in O2 content
normal PO2 and Hb
decreases P50, left shift, large decrease in PvO2 |
|
|
Term
|
Definition
Hb has higher affinity for CO2 in deoxygenated blood
ability of Hb to bind CO2 increases as PO2 decreases |
|
|
Term
|
Definition
increased PCO2, hypoventilation
decreased HCO3/PCO2 ratio
decrease pH
kidney compensates by retaining of HCO3 |
|
|
Term
|
Definition
decreased PCO2, hyperventilation
increase HCO3/PCO2 ratio
increases pH
kidney compensates by retaining H+ or excreting HCO3 |
|
|
Term
|
Definition
for each 10mmHg increase in PCO2
changes pH about 0.8 |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
abnormally low PO2 in arterial blood
<80mmHg |
|
|
Term
|
Definition
| any state in which the availability or utilization of oxygen is impaired |
|
|
Term
|
Definition
anemic
hypoperfusion
histotoxic
overutilization |
|
|
Term
|
Definition
decreased RBC or Hb
decrease O2 content
maintain normal P(A)O2 and P(a)O2 |
|
|
Term
|
Definition
low blood flow
local or systemic |
|
|
Term
|
Definition
cell machinery not using O2
maintain normal P(A)O2 and P(a)O2 |
|
|
Term
|
Definition
| tissue demand exceeds O2 delivery capacity |
|
|
Term
|
Definition
| hypoventilation, diffusion impairment, RL shunting, V/Q mismatch |
|
|
Term
| hypoventilation - hypoxemia |
|
Definition
increases P(a)CO2
decreases P(A)O2 and P(a)O2
tx: increase % oxygen inspired air |
|
|
Term
| causes of hypoventilation |
|
Definition
drugs supressing respiratory center
injury/disease to medulla
diseased respiratory muscles/nervous system to
upper airway obstruction
disease of myoneural junction |
|
|
Term
| diffusion impairment - hypoxemia |
|
Definition
equilibration does not occur between PO2 in pulmonary capillary and alveolus
decrease in DL(CO) [normal is 25 ml/min/mmHg] |
|
|
Term
|
Definition
deoxy blood passes into oxygenated blood of pulmonary veins
decreases PaO2
Dx: 100% inspired oxygen does not relieve hypoxemia |
|
|
Term
|
Definition
most common cause
deviation of V/Q indicates impaired efficiency of CO2/O2 exchange
could be obstructed ventilation or obstructed perfusion |
|
|
Term
| obstructed ventilation - hypoxemia |
|
Definition
alveolar and arterial gases will equalize to normal venous levels
decreased V/Q
lower P(A)O2 and higher P(A)CO2 |
|
|
Term
| obstructed perfusion - hypoxemia |
|
Definition
alveolar gases equalize with atmosphere, arterial gases equalize to normal venous levels
increased V/Q
higher P(A)O2 and lower P(A)CO2 |
|
|
Term
| regional gas exchange characteristics |
|
Definition
perfusion, ventilation, gas exchange: greatest at base
perfusion>ventilation at base (low V/Q)
ventilation>perfusion at apex (high V/Q) |
|
|
Term
|
Definition
highest V/Q
intrapleural pressure more negative -> greater transmural pressure -> larger alveoli -> less compliant, less ventilation
lower intravascular pressure -> less recruit and distend -> increase VR, less blood flow |
|
|
Term
|
Definition
lowest V/Q
intrapleural pressure less negative -> smaller transmural pressure -> smaller alveoli -> more compliant, more ventilation
greater intravascular pressure -> more recruit and distend -> lower VR, more flow |
|
|
Term
| wasted ventilation compensation |
|
Definition
local decrease in PCO2, lower [H+], increase pH
muscle constriction around airway
shift ventilation away from poorly perfused area |
|
|
Term
| wasted perfusion compensation |
|
Definition
local decrease in PO2 leads to hypoxia
induces vasoconstriction
shunts blood away from poorly ventilated areas |
|
|
Term
|
Definition
| pneumonia, asthma, pulmonary edema, regional compliance changes, body position (esp. PT with unilateral lung disease) |
|
|
Term
|
Definition
volume in the lungs at which its smallest airways, the alveoli, collapse
increased CV with diseases of airway
measure using 100% inspired oxygen and monitor N2 of exhale |
|
|
Term
| increased A-a gradient causes |
|
Definition
diffusion impairment
R-L shunting
V/Q mismatch |
|
|
Term
| hypoxemia + normal A-a gradient |
|
Definition
hypoventilation
would also see high PaCO2 |
|
|
Term
|
Definition
| characterized by progressively deeper breaths followed by period of apnea |
|
|
Term
| acute response to altitude |
|
Definition
hypoxemia -> increase ventilatino -> PCO2 decrease -> resp. alkalosis
Cheyne-Stokes breathing |
|
|
Term
| chronic response to altitude |
|
Definition
renal comp for resp. alkalosis (decrease plasma HCO3-)
kidney -> erythropoietin -> increase RBC -> polycythemia
increase 2,3 DPG -> shift Hb curve -> help unload at tissues |
|
|
Term
| most important regulating factor of ventilation |
|
Definition
P(A)CO2
40 to 45 mmHg change --> double V(A) |
|
|
Term
|
Definition
peripheral chemoreceptors mediate
hyperventilation induced
decreases PaCO2 and H2CO3 |
|
|
Term
| peripheral chemoreceptors |
|
Definition
respond to changes in pH, PO2 and PCO2
innervate by CN IX and X
carotid stronger than aortic |
|
|
Term
|
Definition
located in carotid peripheral chemoreceptor
respond to low PO2 -> decrease K+ durrent -> depolarize cell -> release NTs |
|
|
Term
|
Definition
respond to changes in pH brought about by changes in PCO2
CO2 readily diffuses across BBB -> inc PCO2 -> inc [H+] -> stimulate breathing
located near medulla, but separate from respiratory centers |
|
|
Term
| Hering-Beuer inflation reflex |
|
Definition
opposes overinflation of lungs via mechano-stretch-receptors in airways
innervated by CN X
slow adaptation, located in small airways |
|
|
Term
| Hering-Breuer deflation reflex |
|
Definition
collapse of lungs leads to prompt inspiration and increases respiratory frequency
irritant receptors in large and small airways help to mediate
innervated by CN X |
|
|
Term
| C-fiber irritant receptors |
|
Definition
located in pulmonary capillaries and interstitium
sensitive to chemical agents and stretch
reflexes: bradycardia, hypotension, bronchoconstriction, increase mucus secretion, apnea then rapid shallow breathing |
|
|
Term
|
Definition
mediated by receptors in upper airways, tracheobronchial tree
afferents from CN X |
|
|
Term
|
Definition
mediate by receptors in nasal mucosa
afferents from CN V and I |
|
|
Term
|
Definition
induced by immersion of face (esp. in cold water)
produces apnea, profound bradycardia and increased SVR
afferent fibers from CN V |
|
|
Term
| pain fibers + resp. effect |
|
Definition
somatic -> hyperventilatin
visceral -> decreased ventilation or apnea |
|
|
Term
| temperatures sensors + resp. effect |
|
Definition
located in brain and skin
increase -> increase breath freq.
decrease -> deep inspiration |
|
|
Term
| muscle/joint receptors + resp. effect |
|
Definition
provide resp. centers with info about work of breathing
reinforce hyperpnea of exercise |
|
|
Term
|
Definition
located in medulla
neurons active during inspiration
receives inhibitory effects from CN IX and X |
|
|
Term
| ventral respiratory group |
|
Definition
located in medulla
inspiratory and expiratory neurons |
|
|
Term
|
Definition
located in medulla
neurons that inhibit inspiratory cells in DRG and phrenic motor neurons
pacemaker that establishes respiratory rhythm |
|
|
Term
|
Definition
located in lower 2/3 of pons
reinforces inspiratory drive
prolong inspiratory effect
receives inhibitory afferents from vagus |
|
|
Term
| pontine respiratory center (groups) |
|
Definition
pneumotaxic center
located bilaterally in upper 1/3 of pons
periodically inhibtis apeneustic center (cutting short inspiration to give normal, ordered breathing) |
|
|
Term
|
Definition
normal breathing maintained
voluntary control of breathing lost |
|
|
Term
| lesion 1/3 down into pons |
|
Definition
unchecked apneustic center
with vagus: normal breathing
without vagus: apneusis (deep gasp inspriation, pause, small exhale)
loss of voluntary control |
|
|
Term
| lesion between pons and medulla |
|
Definition
breathing maintained, but irregular
w/ or w/o vagus
loss of voluntary control |
|
|
Term
| lesion below medulla respiratory centers |
|
Definition
| breathing ceases, total apnea |
|
|
Term
| hypothalamus + resp. control |
|
Definition
exerts effects
changes breathing pattern in various emotional states |
|
|
Term
| cerebral cortex + resp. control |
|
Definition
profound influence
voluntary breath-holding
highest pulmonary ventilation |
|
|
Term
|
Definition
voluntary respiratory pathway
dorsally located in spinal cord |
|
|
Term
| automatic tonic respiration pathway |
|
Definition
anterior located
deep to rhythmic pathway |
|
|
Term
| automatic rhythmic respiratory pathway |
|
Definition
expiratory medial, inspiratory lateral
anterior and superficial to tonic pathway |
|
|
