resp 3- ventialtion and pressure changes

Question 1

what are static properties of the lung

Answer 1

mechanical properties when no air is flowing

Question 2

why are static properties of the lung necessary

Answer 2

necessary to maintain lung and chest wall at a certain volume

Question 3

what are the 4 static properties

Answer 3

intrapleural pressure (PIP)
transpulmonary pressure (PTP)
static lung compliance
surface tension of lung

Question 4

what are dynamic properties of the lung

Answer 4

mechanical properties when the lungs are changing volume and air is flowing in and out

Question 5

why is dynamic lung properties necessary

Answer 5

necessary to permit airflow

Question 6

3 dynamic properties of the lung

Answer 6

alvoelar pressure (PALV)
dynamic lung compliance
airway and tissue resistance

Question 7

what is bulk flow

Answer 7

exchange of air between the atmosphere and the alveoli due to gas moving from high to low pressure

Question 8

what is boyles law

Answer 8

pressure and volume are inversly proportional at contrant T

p1v1=p2v2

Question 9

which direction does air flow when alveolar pressure is LARGER than atmospheric pressure

Answer 9

air flow out

expiration

Question 10

which direction does air flow when alveolar pressure is SMALLER than atmospheric pressure

Answer 10

air flow in

inspiration

Question 11

bulk flow formula

Answer 11

(alv.press. - atm.press)/resistance

change in pressure/ resistance

Question 12

what are the pleurae

2 types

Answer 12

thin double-layered envelope

parietal and visceral

Question 13

parietal pleura

Answer 13

covers thoracic wall (inside of rib cage)

Question 14

visceral pleura

Answer 14

covers the external surface of the lungs

Question 15

what does intrapleural fluid do

Answer 15

reduces friction of lungs against thoracic wall during breathing

Question 16

what is lung elastic recoil (what does it do)

Answer 16

lung have a tendency to collapse

Question 17

what determines lung volume

Answer 17

the interaction between the lungs and the thoracic cage

Question 18

what is chest wall elastic recoil

Answer 18

pull thoracic cage outward

Question 19

how does elastic recoil equilibriate

Answer 19

inward elastic recoil of lungs balances outward elastic recoil of chest wall

Question 20

what is PIP (definition)

Answer 20

the pressure within the pleural cavity

Question 21

what is PIP like

Answer 21

a vaccuum because it is always subatmospheric (negative pressure)

Question 22

what would happen if PIP=PALV

Answer 22

lungs would collapse

Question 23

what is PALV

Answer 23

the pressure of air inside the alveoli

Question 24

what is PALVs role

Answer 24

directly producing air flow, it is dynamic
it governs the gas exchange between lungs and atmosphere
maintain lung expansion in thorax

Question 25

what is PTP

Answer 25

force responsible for keeping the alveoli open | the pressure graident across the alveolar wall

Question 26

PTP formula

Answer 26

PTP=PAVL-PIP

Question 27

what does PTP determine

Answer 27

lung volume

Question 28

is PTP static or dynamic

Answer 28

static, it does not cause airflow | determines lung volume

Question 29

is PALV static or dynamic

Answer 29

dynamic, determines air flow

Question 30

flow formula

Answer 30

change in pressure/resistance

Question 31

what are the resistive forces in the airway

Answer 31

inertia (negligible) | friction

Question 32

how does friction affect the airway

Answer 32

lung tissue past itself during expansion lung&chest wall tissue surface gliding past eachother (interpleural fluid significantly reduces friciton tho) flow of air through the airways (80%!)

Question 33

when is airflow resistance more sensitive to changes in radius

Answer 33

when its not laminar

Question 34

what are the three different types of airflow

Answer 34

laminar, transitional, turbulent

Question 35

what is laminar airflow

Answer 35

little airflow resistance

Question 36

what is transitional airflow

Answer 36

resistance increases, extra energy to produce vertices

Question 37

where is most transitional airflow

Answer 37

bronchial tree

Question 38

where is most laminal airflow

Answer 38

small airways that are distal to terminal bronchioles

Question 39

what is turbulent airflow

Answer 39

where the effective resistance to airflow is the highest

Question 40

where is most turbulent airflow

Answer 40

in large airways (trachea, larynx, pharynx) large radius large linear air velocities

Question 41

what kind of airflow in small airways

Answer 41

laminar

Question 42

what kind of flow in trachea, larynx and pharynx

Answer 42

turbulent

Question 43

what kind of airflow in bronchial tree

Answer 43

transitional

Question 44

which kind of airflow does poiseuilles law

Answer 44

laminar flow

Question 45

what is poiseuilles law

Answer 45

R=viscocity x length / radius^4

Question 46

what is resistance to airflow most sensitive to (poiseuille)

Answer 46

change in radius

Question 47

what is the total airway resistance in healthy subjects usually

Answer 47

1.5cm H2O/(L/s)

Question 48

why is the resistance lower with bronchioles aligned rather than a few large ariways

Answer 48

because resistance in less in parallel than in a series

Question 49

where does COPD have a dramatic increase in resistance (or other diseases)

Answer 49

in the smalllll airways (<2mm diameter)

Question 50

why is there more resistance in small than large airways in disease states

Answer 50

smooth muscles contraction in walls edema in walls of alveoli and bronchioles mucus in bronchioles