| Question |
Answer |
| measuring lung function |
compare's subject to normal range; identify diseases |
| compliance |
measure of the ease with which the lungs & thorax expand |
| levels of compliance |
expressed in LITERS (volume of air) per centimeter of water (pressure) |
| what is normal compliance? |
0.13L/cm H2O- for every 1 cm H2O change in alveolar pressure, the volume changes by 0.13L |
| the greater the compliance |
the easier it is for a change in pressure to cause EXPANSION of lungs & thorax |
| Example of greater compliance |
emphysema destroys elastic lung tissue; therefore, lungs expand (nothing to bring them back like an overstretched rubber band) and higher than-normal compliance |
| lower-than normal compliance (example) |
pulmonary fibrosis - (non-elastic fibers in lung) so that lungs cannot expand |
| list of conditions that DECREASE compliance |
pulmonary fibrosis - respiratory distress syndrome and pulmonary edema (both collapse alveoli) airway obstructions such as ashtma, bronchitis and lung cancer & deformities of thoracic wall such as scoliosis & khyphosis (wall cannot expand) |
| pulmonary volumes are measured by |
spirometry - process of measruing volumes of air that move in & out of respiratory system |
| tidal volume (TV) |
air inspired or expired with each breath |
| inspiratory reserve volume (IRV) |
amount of air forcefully inspired (after quiet inspiration) |
| expiratory reserve volume (ERV) |
volume of air forcefully expired (after a normal expiration) |
| Residual volume (RV) |
volume of air remaining in the lungs after forceful expiration |
| Vital capacity (VC) |
greatest extreme in air volume between inspiration & expiration |
| pulmonary capacities |
sum of two or more pulmonary volumes |
| Inspiratory capacity |
Tidal Volume TV plus Inspiratory reserve volume (IRV) - amount of air that a person can inspire maximally (after normal breath) |
| Functional residual cpacity |
Expiratory reserve volume plus resideula volume, which is amount of air remaining in the lungs at the end of normal respiration |
| Vital capacity |
IRV plus TV plu ERV |
| Total lung capacity |
TLC - normal 6000-7500 mL |
| FEV - forced expiratory vital capacity |
subject inspires maximally & then exhales maximally into a spirometer - as quickly as possible |
| FEV one |
amount of air expired during the first second of the FEV test |
| minute volume |
amount of air moved into & out of respiratory system each minute |
| minute volume is calculated |
respiratory rate times TV tidal volume - normal about 12-18 breaths per minute |
| Average minute volume calculation |
TV usually equals 500 mL times 12 breaths per minute or about 6 L/min |
| does minute ventialtion measure the amount of air available for gas exchange? |
no, because some parts of lungs don't actually exchange gas - only the alveoli & alvolar ducts & respiratory bronchioles |
| dead space |
where gas exchange does NOT take place-- |
| anatomic dead space |
nasal cavity, pharynx, larynx, trachea, bonchi bronchioles & terminal bronchioles |
| physiologic dead space |
all of the anatomic dead space PLUS any alveoli where gas exchange is not normal |
| conditions which increase physiologic dead space |
lung cancer, strep throat, emplysema (which degenerate alveolar walls) |
| dalton's law of partial pressure |
in a mixture of gas, the "partial pressure" of each gas is added to make 100%; add nitrogen, oxygen, carbon dioxide to get total pressure |
| what adds to partial pressure? |
water vapor pressure |
| what effect does water vapor pressure have on lungers? |
affect pressure of total gases & absorption in body--remember that air is humidified in nasal conchae- |
| partial pressure are affected by |
1. humidified air 2. oxygen diffusing from alveoli into blood along with carbon dioxide diffusing from pulmonary capillaries into alveoli and then - air within alveoli is only partially replaced with atmospheric air during respiration |
| Henry's law (effecting lungs) |
concentration of dissolved gas = partial pressure of each gas times the solubility coefficient |
| Henry's law in liquids |
gases move from areas of higher to areas of lower partial pressure |
| solubility coefficient |
physical characteristic of each gas-whcih cannot be altered |
| henry's law - decompression sickness "the bends" |
increased depth means increased pressure; nitrogen bubles come out of blood if pressure changes too quickly |
| hyperbaric oxygenation |
increase pressure to force more oxygen into the blood |
| how is diffusion of bases, ventilatio & pulmonary blood flow affected |
respiratory membrane thickness, change in surface area, or diffusion coefficient of gas |
| respiratory membran thickness |
increased in diseases tuberculosis, pneumonia, advanced silicosis - also plumonary edema casuded by failure of left side of heart causes increase in thicckness of respiratory membrane |
| surface area of lungs |
normally 70m2-however, emphysema (destroys alveolar walls) lung cancer or tuberculosis decrease surface area |
| diffusion coeficient of gas |
"diffusion coefficient" of oxygen is rate "one" and of carbon dioxide is "20" therefore carbon dioxide diffuses through respiratory membran 20 times more readily than oxgen does |
| when respiratory membrane becomes damaged |
capacity to move oxygen into blood is impaired- causes oxygen deprivation |
| relationship between ventilation & pulmonary capillary blood flow |
2 ways to disrupt-ventilation exceeds blood (in heart attack) or ventilation not great enough to oxygenat blood (asthma) |
| anatomic shunt |
normal for some deoxygenated blood to mix with oxygenated blood in lungs |
| physologic shunt |
blood from anatomic shunt & any blood NOT oxygenated in pulmonary capillaries (for instance if there is a blocked bronciole) |
| gravity affects regional blood flow |
pressure at lung base is greater; therefore more blood flows at base |
| regional blood flow increases |
with exercise - more blood at apex & greater gas exchange |
| smoking |
decreases lung capacity-smokers have less gas exchange |
| carbonic anhydrase |
buffering system in blood - carbon dioxide & water are changed w/enzyme into carbonic acid |
| bohr effect |
as pH of blood declines, oxygen is released for use in tissues; |
| during exercise, your temperature goes up |
this also decreases tendency of oxygen to bind to hemoglobin; therefore it is released where needed |
| effects of 2,3-bisphosphglercerate BPG |
BPG binds to hemoglobin & increases its ability to release oxygen |
| fetal hemoglobin |
fetus is able to absorb more oxygen from mother - 50% greater in fetal hemoglobin |
| double Bohr effect |
in fetal hemoglobin, this means that baby gets maximum oxygen |
| medullary respiratory center |
consists of dorsal respiratory group & ventral respiratory group |
| dorsal respiratory group |
stimulate the inspiration |
| ventral respiratory |
stimulate experiration |
| pontine (pneumotaxic) |
pons is involved in switching between expiration & inspiration |
| modification of ventilation - 7 factors |
1. change in ways you breathe 2. emotions 3. chemoreceptors 4. exercise 5 pain 6. sneeze-cough reflex 7. increase in body temperature |
| herring-breuer reflex |
in infants, prevents overinflation of lungs & regulates basic breathing - 2. in adults, important when tidal volume is high during exercise. |
| where does the lining of the respiratory tract change? |
In oropharynx - where food also must pass--the epithelium is stratified squamous epithelium (like oral cavity) |
| what is lining of nasal cavity and superior portion of pharynx? |
pseudo stratified ciliated columnar epihtelium |
| what is lining of lower respiratory system? |
pseudo stratified ciliated columnar epithelium |
| what is lining in smaller bronchioles? |
cuboidal epithelium with scattered cilia |
| what is lining of alveoli? |
very delicate simple squamous epithelium |
| lamina propria |
underlying layer of tissue of a mucous membrane |
| hard palate is made up of what bones |
maxillary and palatine bones |
| soft palate marks the end of the |
nasopharynx |
| what bones form bridge of nose? |
nasal bones plus extensions of the frontal (forms small attachment) and maxillary bones |
| nasal septum |
the anterior is cartilage and the posterior is the vomer bone and the perpendicular plate of the ethmoid bone |
| external nares |
external opening of the nose |
| internal nares |
choanae - openings into the pharynx |
| what two special bones constitute the bony part of the nasal septum? |
vomer bone and the perpendicular plate of the ethmoid bone |
| paranasal sinuses (4) |
named for bones they are located in; frontal, maxiallary, sphenoidal & ethmoid |
| what is ethmoid sinus also called? |
the ethmoid labyrinth (near eyes) |
| what supports the nsal concahe? |
part of ethmoid bone |
| where is crista galli? what is on either side of crista galli? |
olfactory fossa |
| what forms the floor of the olfactory fossa? |
the cribiform plate of the ethmoid bone |
| conjunctivitis |
inflammation of thin membrane covering eye -also called "pink eye" |
| sinusitis |
inflammation of mucou membrane of any sinus, especially paranasal sinuses |
| rhinitis |
inflammation of the nasal mucous membrane |
| two major bones that make up hard palate |
maxillary and palatine bones |
| function of soft palate & uvula |
prevents swallowed material from entering the nasal cavity & nasopharynx |
| palatine process of maxillary bone |
anterior portion of hard palate |
| palatine bones |
posterior portion |
| nasal conchae are connected to |
ethmoid bone - |
| nasal chonchae consist of |
"turbinates" and "meatus" tunnels |
| purpose of turbinates |
clean air, warm air, & humidifying incoming air |
| tonsils in nasopharynx and oropharynx |
|
| swallowing |
opening & closing of glottis involves rotational movement of arytenoid cartilages that move vocal folds; epiglottis is bent over glottis; bolus glides over it |
| eustachian tube opening |
in nasopharynx-below pharyngeal tonsil |
| cartilaginous rings -how many in trachea? what is distinctive feature? |
15-20 C-shaped rings - with cartilage onANTERIOR wall-posterior wall has NO CARTILAGE |
| what is in the space on the trachea where there is no cartilage? |
trachealis muscle - causes coughing reflex? |
| what is posterior to the trachea? |
the esophagus - trachea can move to allow large bolus to pass |
| tissue lining trachea |
dense regular connective tissue with pseudo stratified ciliated epithelium |
| remember - what is TISSUE |
dense regular connective tissue |
| Re-absorptionand filtration of proximal & distal tubule |
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