Respiratory phys. Lung Vol and capacities 1 of 2

Question 1

what are the four main funcitonso f the respiratory sytstem?

Answer 1

1. exchange gases between the atmosphere and the blood
2. homeostatic regulation of blood pH
3. Protection from inhaled pathogens and irritating substances
4. vocalization

Question 2

differentiate between external and celluar respiration

Answer 2

1. external
   
   1. movement of gases between the enviornment and the bodys cells
2. cellular respiration
   
   1. intracellular reaction of O2 with organic molecules to prduce CO2, water andATP

Question 3

what are the four phases of external respiration?

Answer 3

1. exchange of air between the atmosphere and the lungs
   
   1. ventilation/breathing
      
      1. inspire/exspire
2. exchange of O2 and CO2 between the lungs and the blood
3. transport of O2 and CO2 by the blood
4. exchange of gases between blood and the cells

Question 4

what organizes the flow of air into and out of the lungs?

Answer 4

Conducting zone

Question 5

what division is lined with alveoli and facilitates gas exchange?

Answer 5

respiratory zone

Question 6

what temp and humidity does the conducting zone act on the inspired air?

Answer 6

warm: 37C
humidify: 100%

Question 7

trachea and bronchi are lined by two major cell types

1. function
2. secretions of each

Answer 7

Epithelial cells/ goblet cells

1. filtration and ciliated respritory epithelium
   
   1. goblet- secret mucus
   2. epithithelial- secrete dilute saline
2. cilia move the mucus layer toward the phrynx, removing trapped pathogens and particulate matter

Question 8

what does smoking do?

Answer 8

paralyzed cilia, increasing mucus-> smokers cough

Question 9

explain the difference between cilliary dyskenesia and cystic fibrosis.

how can you test some one for cystic fibrosis?

Answer 9

1. ciliary dyskenesia
   
   1. genetic disorder where person has malformed cillia and they do not funciton properly, males are sterile (sperm)
2. Cystic fibrosis
   
   1. mustated CFTR: cyteic fibrosis transmembran conductance regulator
   2. water does not move into airways with osmosis
   3. lack of slaline layer make thick sticky mucuc
   4. mucus remains in the airway
   5. recurring lung infection
   6. test
      
      1. sweat test
         
         1. normal sweat ducts use the CFTR to reabsorb water as the isotonic solution travels down the duct. this generates a hypotonic
         2. Mutation in the CFTR leads to hypotonic - isotonic sweat.

Question 10

what is the location of dead space?

Answer 10

150mL in the conducting zone - do not participate in gas exchange

Question 11

What are the important layers on the respiratory epithelium

Answer 11

watery layer in contact with the cilia, mucos layer superficial to the watery layer.

This watery layer is important b/c the cilia cannot beat in the mucus layer.

patietns with cystic fibrosis have no watery layer and cannot remove the mucus, b/c the cilia cannot beat

Question 12

______ leads to the Activation of what receptor leads to muscle relaxation and dilatino of the airway

Answer 12

sympathetic adrenergic neurons activate B2 receptors

1. B2 adrenergic agonists
   
   1. epinephrine
   2. albuterol

Question 13

_____ activates this receptor leading to contraction and constriction

Answer 13

parasympathetic cholinergic neurons activate muscarinic receptor

1. muscle contraction and constriction of airways

Question 14

what is included in the respiratory zone?

Answer 14

1. respiratory bronchioles
2. alveolar ducts
3. alveolar sacs
4. alveoli

Question 15

how many alveoli are present in each lung?

Answer 15

300 million

Question 16

Blood flow with respect to the lungs is

• highest in the
• lowerst in the

Answer 16

• hiest at the base (bottom)
• lowest at the apex(top)

laying down decreases this affect

Question 17

how is blood flow regulated with respect to resistance?

Answer 17

pulmonary blood flow is regulated by alterin the resistance of the pulmonary arterioles

• O2 is the main factor

Question 18

descrive the respriration

• O2 molecules react to produe CO2, water and ATP

Answer 18

cellular respiration: intracellular reaction of O2 with organic molecules to produce CO2, water and ATP

Question 19

describe the type of respiration

• movement of gases from eviornment and the bodys cells

Answer 19

external respiration: movement of gases between the environment and the body’s cells

Question 20

what two items make up a respiratory cycle?

Answer 20

inspiration + expiration

Question 21

define the following terms

1. Vt
2. IRV
3. ERV
4. RV

Answer 21

1. tidal volume
   
   1. the volume of air fluctuating the most of the time. during normal, quiet breathing
   2. 500ml
2. inspiritory reserve volume
   
   1. the maximum amount of air that can be added to normal tidal volume
   2. 3000ml
3. expiratory reserve volume
   
   1. amount of air that can be expired in addition to norma ltidal expiration, just following normal breathing
   2. 1200ml
4. residual volume
   
   1. volume of air remaining in the lungs after a max forced expiration
   2. NOT MEASURABLE ON SPIROMETER

Question 22

Define the inspiritory capacity

Answer 22

inspiratory capacity = Vt + IRV

Question 23

define Vital Capacity

Answer 23

Vital capacity = Vt + IRV +ERV

• ~4700ml
• the maximum amount of air that can be moved through the lungs
• increases with body size, male gender and physical conditioning

Question 24

define

total lung capacity

Answer 24

total lung capacity = Vt + IRV + ERV +RV

• TLC is the toal volume of air that the lungs can hold
• since RV cannot be measured by spirometry, TLC cannot be measured by spirometry

Question 25

define the functional residual capacity

Answer 25

Functional residual capacity = ERV +RV

• this is the volume remaining in the lungs after a normal tidal volume is expired; it can be though of as the equilibrium volume of the lungs
• Since RV cannot be measured via spirometry, FRC cannot be measured by spirometry

Question 26

Of the volumes used to describe the lungs which can and cannot be measured by spirometry.

Answer 26

• can be measured
  
  • inspiratory capacity = Vt + IRV
  • Vital capacity = VT +IRV + ERV
• CANNOT BE MEASURED- b/c RV cannot be measured
  
  • ​total lung capacity = Vt +IRV +ERV +RV
  • Functional residual capacity = ERV + RV

Question 27

Answer 27

Question 28

volume of the airways and lungs that does not participate in gas exchange?

Answer 28

dead space = anatomic dead space is the volume of the conducting airways

• 150ml
• accounting for the space in the nose/mouth, trachea, bronchi, and bronchioles

Question 29

for a typeical Vt of 500ml, how much actually meet the alveoli?

Answer 29

500ml

dead space = 150ml

500-150=350

350ml

this freshly inspired air is mixed with alveolar air from the precious breath

Question 30

pulmonary embolism blocks the alveoli and is equivilent to generating more

Answer 30

dead space

normally ventilation and perfusion are well matched, but certain pathologies cause an increase in physiologic dead space.

Question 31

how can you calculate the physiologic dead space?

• how much CO2 is estimated to be inspired
• location of CO2 from expired air
• Dead space contribution to CO2
• formula
• What is needed for the above formula?

Answer 31

• almost no CO2 in inspired air
• CO2 in expired air comes from exhange in functioning alveoli
• presence of dead space dilutes the CO2
  
  • Dead space neither exchanges nor contributes CO2
• Volume of the physiologic dead space = Vt x ((PaCO2-PeCO2)/PaCO2)
  
  • fraction represents the dilution of alveolar CO2 be dead space
• since alveolar air can’t be sampled directly, the CO2 in systemic arterial blood is used to estimate the CO2 in air

Question 32

minute volume =

*

Answer 32

Total pulmonary ventilation = minute volume

• determines the efficiency of breathing
• volume of air moved into and out of the lungs/min
• TPV = ventilation rate x Vt
  
  • Normal adult
    
    • 12-20breaths/min
    • ave Vt = 500 ml
  • ~TPV = 12 breathes/min x 500mL/breaths
    
    • = 6000mL/min->6L/min
• But this is not the amount of fresh air reaching the alveoli b/c anatomic dead air space ~150mL, so subtract 150mL per breath?

Question 33

compare TPV to AV

Answer 33

Total pulmonary ventilation- does not take into account of dead space

• 6000mL

Alveolar Ventilation - makes adjustment for the anatomic dead space

• 4200mL
• Va =(Vt-Vd) x breathes per minute

Question 34

Answer 34

check values

Question 35

Answer 35

Question 36

Define FVC and FEV

Answer 36

1. FVC= forced vital capacity
   
   1. this is the total volume of air that can be forcefully expired after a maximal inspration
2. FEV = Forced expiratory volume
   
   1. is the volume expired in the first second

Question 37

describe the following charts. Determine the ratios

Answer 37

1. normal
   
   1. FEV/FVC
      
      1. 4/5=0.8
      2. 80%
2. obstructive disease
   
   1. asthma
   2. FEV/FVC
      
      1. 2/3 = 0.67
      2. below80%
3. restrictive disease
   
   1. fibrosis
   2. FEV/FVC
      
      1. 4/4=0
      2. above 80%

Question 38

interpret the following charts.

Answer 38

Question 39

Normal/resting state

Answer 39

end of tidal volume

Question 40

what is the volume of dead space?

Answer 40

150mL

Question 41

what is the resting location of the lung?

Answer 41

FRC= where the lung collapse and chest wall are equal in pressure.