Resp

Question 1

What are the anatomical components in the respiratory pump?

Answer 1

Muscles - diaphragm + intercostals
Pleura -parietal and visceral
Nerves - C 3,4,5 diaphragm alive, sensory, motor, autonomic
Airways - incl dead space

Question 2

How much anatomic and alveolar dead space is there in airways?

Answer 2

Anatomic - 150 ml

Alveolar - 25 ml

Question 3

At rest when is Hb fully saturated?

Answer 3

25% of the way through Hb is fully saturated at rest

Question 4

What factors does alveolar perfusion depend on?

Answer 4

Pulmonary alveolar pressure, pulmonary arterial pressure, alveolar pressure

Question 5

What do pulmonary artery smooth muscle do during hypoxia

Answer 5

Smooth muscle in pulmonary arteries contract, constricting pulmonary arteries. For a V/Q match

Question 6

At rest what percentage of pulmonary vessel total capacity is used?

Answer 6

30%

Question 7

Arterial CO2 pressure equation

Answer 7

PaCO2 = k VCO2 / VA

Question 8

Alveolar Oxygen pressure equation

Answer 8

PACO2 = PiO2 - PaCO2/ R

Question 9

3 ways CO2 is carried in blood

Answer 9

1) Bound to Hb protein chain (23%)
2) CO2 dissolved in plasma
3) As HCO3-

Question 10

Causes of increased CO2

Answer 10

Less ventilation, more dead space ventilation (rapid shallow breathing), increased dead space by V/Q mismatch
More CO2 production

Question 11

4 causes for hypoxaemia

Answer 11

1) Alveolar hypoventilation
2) Reduced PiO2
3) V/Q mismatch
4) Diffusion abnormality

Question 12

Layers for gas exchange

Answer 12

7 layers
alveolar epithelium, tissue interstitium, capillary endothelium, plasma layer, red cell membrane, red cell cytoplasm, Hb binding forces