Ventilation and gas exchange

Question 1

What is the definition of hyperventilation

Answer 1

excessive ventilation of the lungs atop of metabolic demand (results in alkolysis )

Question 2

What is the definition of tachypnoea

Answer 2

abnormally fast breathing

Question 3

Describe what happens in maximum inspiratory effort

Answer 3

rapid increase in lung volume that then plateaus

Question 4

Describe what happens in maximum expiratory effort

Answer 4

rapid decrease in lung volume, then that plateaus

Question 5

What is residual volume

Answer 5

Residual volume (RV) is the volume of air remaining in the lungs after maximum forceful expiration. In other words, it is the volume of air that cannot be expelled, thus causing the alveoli to remain open at all times.

Question 6

Why can some volume of air not be expelled from the lungs and what is this called (maybe use an analogy)

Answer 6

called residual volume and held together by mucus and surfactant etc
Analogy - if you lick a bank card and stick it on a surface you cant pick it up bc the water is stuck between the bank card and the table

Question 7

what is inspiratory reserve volume

Answer 7

total air that can be inspired minus tidal volume

Question 8

what is expiratory reserve volume

Answer 8

total air that can be expelled minus tidal volume

Question 9

How is total lung capacity defined

Answer 9

residual volume + expiratory reserve volume + tidal volume +inspiratory reserve volume

Question 10

What is vital capacity and how do you remember this

Answer 10

vital - how much do you have to live

vital cacpity = total lung capacity - residual volume

Question 11

What is a feature of the lung volumes

Answer 11

NEVER OVERLAP

Question 12

how do you calculate minute ventilation (L/minute)

Answer 12

tidal volume (L/breathe) * breathing frequency (breathes/ minute)

Question 13

How do you calculate alveolar ventilation (L/min)

Answer 13

(tidal volume - dead space)* breathing frequency

Question 14

Describe what the conducting zone is made out of

Answer 14

1) 16 generations (from the nose/ mouth thru the oro and lasopharynx and the laryngopharynx and the trachea and the bronchus and bronchioles)
2) no gas exchange
3) typically 150ml
4) equivalent to anatomical dead space

Question 15

what is another name for anatomical dead space

Answer 15

conducting zone

Question 16

Give characteristics of the alveolar dead space

Answer 16

1) non perfused parenchyma
2) no gas exchange
3) typically 0ml in healthy adults

Question 17

How do you calculate physiological dead space

Answer 17

physiological dead space = anatomical dead space + alveolar dead space

Question 18

Describe the respiratory zone

Answer 18

1) 7 generations
2) gas exchange
3) typically 350 ml in adults
4) air reaching here is equivalent to alveolar dead space