Phys 37

Front 1

Respirations 4 major functions

Back 1

1) pulmonary ventilation 2) diffusion of O2 and CO2 btwn alveoli and blood 3) transportation of O2 and CO2 in blood and body fluids 4)regulation of ventilation

Front 2

how are lungs expanded

Back 2

downward movement of diaphragm and elevation of ribs

Front 3

what causes slight suction btwn parietal pleura and lung

Back 3

lymphatic channels

Front 4

Pleural pressure definition

Back 4

pressure of fluid btwn lung pleura and chest wall pleura (slight neg pressure)

Front 5

pleural pressure at beginning of inspiration and end inspiration

Back 5

negative 5 cm of water and negative 7.5 cm of water

Front 6

zero reference pressure in the airways

Back 6

atmospheric pressure (0 cm h2o)

Front 7

alveolar pressure during inspiration and expiration

Back 7

negative 1 cm water and positive 1 cm water

Front 8

transpulmonary pressure

Back 8

difference btwn alveolar and pleural pressure - measure of elastic forces in lungs

Front 9

compliance of lungs

Back 9

extent to which the lungs will expand for each unit increase in transpulmonary pressure (~200 mL of air per cm of water)

Front 10

inspiratory compliance curve

Back 10

slow to fill lungs at first, then more rapid

Front 11

expiratory compliance curve

Back 11

rapidly exits at first, then slower

Front 12

Tissue elastic forces

Back 12

represents 1/3 of the total lung elasticity

Front 13

Fluid-air surface tension

Back 13

represents 2/3 of the total lung elasticity

Front 14

surfactant

Back 14

reduces surface tension of water

Front 15

what secretes surfactant

Back 15

type II alveolar cells

Front 16

what is in surfactant

Back 16

phospholipids, proteins, and ions (most important are dipalmitoylphospatidylcholine, surfactant apoproteins, and calcium ions)

Front 17

How does dipalmitoylphospatidylcholine work?

Back 17

partially dissolves - part remains on surface (surface has 1/12 to 1/2 tension of pure water)

Front 18

pressure in occluded alveoli

Back 18

2 times surface tension/radius of alveolus (about 4 cm of water in average alveolus with surfactant)

Front 19

alveolar pressure in premature infants

Back 19

double normal due to small radius, also less/no surfactant production

Front 20

compliance of lungs including thoraxic cage

Back 20

half the compliance of lungs alone

Front 21

Work of inspiration-3 components

Back 21

1) expand lungs against elastic forces 2) overcome viscosity of lung and chest structures - tissue resistance 3) overcome airway resistance

Front 22

Quiet respiration energy expenditure

Back 22

3 to 5 percent total energy

Front 23

Tidal volume

Back 23

volume inspired/expired with each noraml breath (~500 mL in adult male)

Front 24

Inspiratory reserve volume

Back 24

extra volume of air that can be inspired above tidal volume with full force (~3000 mL)

Front 25

expiratory reserve volume

Back 25

max extra volume of air that can be expelled by forceful expiration (~1100 mL)

Front 26

residual volume

Back 26

volume air remaining in lungs after most forceful expiration (~1200 mL)

Front 27

Inspiratory capacity

Back 27

tidal volume plus inspiratory reserve volume (~3500 mL)

Front 28

functional residual capacity

Back 28

expiratory reserve volume plus residual volume (~2300 mL); amount left in lungs after normal expiration

Front 29

vital capacity

Back 29

inspiratory reserve volume plus tidal volume plus expiratory reserve volume (4600); max amount of air that can be expired

Front 30

total lung capacity

Back 30

vital capacity plus residual volume; max expansion with greatest possible effort (~5800 mL)

Front 31

capacity in men vs woman

Back 31

20-25 percent less in women than men

Front 32

measuring functional residual capacity (FRC)

Back 32

helium dilution (FRC = (initial He concentration/final He concentration -1)*initial volume spirometer

Front 33

minute respiratory rate

Back 33

total amount of new air entering respiratory passages each minute; about 6L/min normal…can go up to 200L/min (tidal volume times resp rate/min)

Front 34

alveolar ventilation

Back 34

rate at which new air reaches alveoli

Front 35

dead space

Back 35

air that enters respiratory passage, but never enters alveoli (generally ~150 mL)

Front 36

measuring dead space

Back 36

measure changes in nitrogen concentration after taking deep breath of pure O2

Front 37

calculating dead space

Back 37

Vd = (VO2*Vexpired)/(VN2+VO2)

Front 38

physiological dead space

Back 38

dead space + alveolar dead space

Front 39

alveolar ventilation rate

Back 39

resp frequency * (tidal volume - physiologic dead space); noramal about 4200 mL/min

Front 40

composition of trachea and bronchi btwn catilage plates

Back 40

Smooth muscle

Front 41

walls of bronchioles

Back 41

almost entirely smooth muscle

Front 42

walls of respiratory bronchioles

Back 42

pulmonary epithelium plus few smooth muscle fibers

Front 43

Many obstructive diseases result in narrowing of what

Back 43

smaller bronchi and larger bronchioles

Front 44

Where is the greatest amount of resistance to airflow

Back 44

larger bronchioles and bronchi near trachea (few in comparison to terminal branches)

Front 45

Smaller bronchioles are easily occluded by…

Back 45

1) muscle contration in walls 2) edema in walls 3) mucus collection in lumens

Front 46

sympathetic stimulation location

Back 46

few fibers penetrate central portions of lungs, but respond to norepinephrine and epinephrine released by adrenal medulla into blood

Front 47

sympathetic stimulation effect

Back 47

dilation of bronchial tree (beta-adrenergic receptors)

Front 48

parasympathetic stimulation

Back 48

penetrate lung parenchyma, cause mild/moderate constriction

Front 49

What can be used to block parasympathetic acetylcholine release

Back 49

atropine

Front 50

Substances in lungs that cause bronchiolar constriction

Back 50

histamine and slow reactive substance of anaphylaxis (released by mast cells)

Front 51

where does ciliated epithelium end

Back 51

as far down as terminal bronchioles

Front 52

carina

Back 52

point where trachea splits into bronchi

Front 53

cough reflex caused mainly by what nerve

Back 53

vagus

Front 54

cough sequence

Back 54

2.5 L air rapidly inspired; epiglottis closes and vocal cords shut tight; abdominal muscle contract forcefully; vocal cords and epiglottis open widely

Front 55

sneeze reflex

Back 55

like cough reflex except through nasal passageways

Front 56

nerve mainly responsible for sneeze reflex

Back 56

trigeminal

Front 57

function of nasal passageways

Back 57

1) warm air 2) moisten air 3) filter air

Front 58

Size of particles that can pass normal nasal passageways

Back 58

almost no particles greater than 6 um (smaller than RBCs)

Front 59

where do most small dust particles settle in the lungs

Back 59

smaller bronchioles (result of gravitational precipitation) - unless smaller than 0.5 um (go to alveoli)