quotes from rosens notes.... lecture 7

Question 1

which divisions of the lung conduct zone

Answer 1

bronchi
bronchioles
terminal bronchioles

Question 2

what is the conduction zone for?

Answer 2

BULK movement of air
no respiratory function
helps defend the lungs

Question 3

which divisions of the lung are respiratory (aka transitional)

Answer 3

respiratory bronchioles
alveolar ducts
alveolar sacs

Question 4

what is the respiratory zone for?

Answer 4

gas exchange via the acinus

Question 5

how does branching of bronchioles affect surface area?

Answer 5

it durastically increases surface area and thus, the air VELOCITY SLOWS down

Question 6

what provides circulation in the alveolus

Answer 6

pulmonary artery, capillary bed and pulmonary vein

Question 7

distance between blood and air in an alveolus

Answer 7

<0.5 microns. tiiiiny

Question 8

what are some lung/respiratory system functions

Answer 8

humidification
warming
filtration

Question 9

if your lung dries out, what happens

Answer 9

“dessication of respiratory surface … could lead to infection”

Question 10

the URT filters air. what are the four sizes of particles?

where are those particles trapped?

Answer 10

larger than 10 microns ==> hairy nose
5-10 microns ==> sinuses, pharynx
2-5 microns ==> bronchioles
alveoli (this is where smoke goes)

Question 11

where is mucous not present

Answer 11

mucous only goes as far as terminal bronchioles. this makes suspension of very fine particles in the acini very troublesome

Question 12

how do you get rid of particulates

Answer 12

cilia ==> they beat and propel the mucous suspension toward pharynx
alveolar macrophages ==> phagocytic destruction of debris, microbes
sneezing and coughing

Question 13

sneezing and coughing is effective for?

Answer 13

the first 12 ish branch points of the R. system

Question 14

what space allows for lung mvmt

Answer 14

the intrapleural space couples the lung surface to the chest wall and diaphragm

Question 15

what does the lung natrually wants to __ but we prevent it by __

Answer 15

collapse; the recoil force of the chest wall and diaphragm give it a slightly negative INTRAPLEURAL pressure, and zero INTRAPULMONARY pressure

Question 16

how does a lung collapse

Answer 16

by exposing the chest cavity to atmospheric pressure
or
introducing air into the intrapleural space (pneumothorax)

Question 17

majority of inspiration is due to? the rest is?

Answer 17

diaphragm (75%)

the rest is external intercostals, scalene, sternomastoid…. (thats not a muscle?)

Question 18

why can you breathe without much resistance

Answer 18

there is a large cross sectional area of the LRT, (therefore, low TOTAL resistance to flow).
this set-up allows you to move large amounts of air with very small pressure differences

Question 19

expiration at rest

Answer 19

due solely to recoil of elastic elements in lungs

they recoil until their force equals the force of the chest wall

Question 20

inadequate expiration results in

Answer 20

limited USEFUL lung capacity

Question 21

airway resistance =

Answer 21

how easily does air go throuigh the tracheo-bronchial tree?
> asthma
> CF

Question 22

thoracic resistance examples

Answer 22

fractured rib

obesity

Question 23

surface tension tries to minimize?

Answer 23

surface area of the lyng

Question 24

compliance =

Answer 24

change in volume / change in pressure

Question 25

in alveoli what does DECREASED compliance try to do to your lungs? Compliance is inversely proportional to?

Answer 25

it tries to keep them closed (tries to collapse them). Compliance inversely related to surface tension. (increased tension= decreased compliance)

Question 26

what does surfactant do to the lung?

Answer 26

induces an AREA DEPENDANT effect on tension, which changes how water molecules interact as a chemist, my (more accurate) definition is... "it helps water attract to other surfaces, thereby reducing waters attraction to itself... lowering tension"

Question 27

relationship between radius and pressure

Answer 27

a small R needs more pressure to blow up an alveolus

Question 28

what does surfactant do to: | work, compliance, tension

Answer 28

``` reduces work increases compliance (aka decreases resistance) decreases tension (compensates for small radius of alveoli) ```

Question 29

how do you get preemies to breathe

Answer 29

positive pressure vent. | > surfactant production begins @ 32 wks

Question 30

tidal volume=

Answer 30

NORMAL breath volume | aka TV

Question 31

expiratory reserve volume=

Answer 31

ERV; maximum volume of forced exhale AFTER NORMAL breathing

Question 32

inspiratory reserve volume =

Answer 32

IRV; maximum volume of forced inspiration AFTER NORMAL breathing

Question 33

vital capacity=

Answer 33

MAX volume you can INHALE and EXHALE | VC = TV + IRV + ERV

Question 34

residual volume =

Answer 34

RV; volume of air left in lungs AFTER MAXIMUM EXHALE

Question 35

functional residual capacity=

Answer 35

- volume of air in lungs AFTER NORMAL EXHALE | - describes the balance of force between lung collapse and chest wall recoil

Question 36

downfall of vital capacity measurements

Answer 36

they are only static numbers, they don't tell you anything about the flow of air in a lung

Question 37

how do you measure dynamic properties of a lyng? whats normal

Answer 37

- forced expiratory volume (over 1 sec) and forced vital capacity; ** we did this in lab. - FEV / FVC should be about 0.8 - useful for COPD and asthma

Question 38

what causes airway resistance

Answer 38

- due to frictional loss of energy from walls of airways

Question 39

obstructive diseases

Answer 39

increased airway resistance and CO2 retention

Question 40

Asthma is an example of

Answer 40

bronchospastic or reversible obstructive condition because the increase in resistance is due to bronchocontriction

Question 41

exercise induced asthma

Answer 41

- cough, wheezing, chest tightness - may be due to heat and water loss during rapid respiration - (or maybe just that it doesn't bother you until you try do exercise)

Question 42

emphysema is an example of

Answer 42

- irriverible obstructive condition - forced residual capacity increases and elastic work decreases - airway ressitance increases - tendency to retain co2

Question 43

what happens to FEV/FVC in obstructed airway

Answer 43

- decreased ratio - result of increased airway resistance - in some cases you also have a loss of lung elasticity/recoil

Question 44

examples of restrictive diseases

Answer 44

- atelectisis - consolidation - pleural effusion - respiratory distress syndrome - pneumothorax - ** i would add scoliosis and broken rib

Question 45

atelectesis =

Answer 45

collapse of part or entire lung

Question 46

cnosolidation =

Answer 46

filling of alvolar spaces with inflammatory exudates

Question 47

pleural effusion=

Answer 47

- heart failure, - hypoproteinemia - infection - neoplasm - thoracocentesis

Question 48

respiratory distress syndrome

Answer 48

most common example of restrictive disease usually in premature babies, but also in : - near drowning - acid aspiration

Question 49

restrictive disease=

Answer 49

- reduction of total lung capacity - although FEV/FVC increases, the absolute movement of be air decreases because the functional residual capacity decreases

Question 50

dead space =

Answer 50

volume of air in first 16 segments that does nothing for oxygen absorbtion.... only for air condutiobn

Question 51

to live, __ must be greater than ___

Answer 51

TV must be larger than dead space

Question 52

compare rapid shallow breaths to deep slow ones

Answer 52

volume wise, the two may move the same amount of air. | rapid breathing does not overcome the DEAD SPACE, so alveoli don't oxygnate as well

Question 53

good analogy for dead space?

Answer 53

think about snorkeling with suuper long tube.... it wouldn't work. you'd keep breathing the same air