Respiratory Pt. 2

Question 1

What are the three steps of Respiratory Physiology?

Answer 1

1) Pulmonary Ventilation
2) Gas Exchange
3) Gas Transport

Question 2

What is Pulmonary Ventilation?

Answer 2

Physical movement of air into and out of lungs

Question 3

What is Gas Exchange?

Answer 3

Diffusion of gasses across the respiratory membrane into alveolar capillaries, and from capillaries into other tissues

Question 4

What is Gas Transport?

Answer 4

Movement of oxygen and carbon dioxide b/w lungs and other tissues

Question 5

What occurs in Pulmonary Ventilation?

Answer 5

1) Physical movement of air into and out of the Respiratory Tract
2) Primary function is to maintain alveolar ventilation
3) Alveolar ventilation prevents build up of CO2 and maintains adequate O2

Question 6

What occurs in the movement of air? What is the movement of air?

Answer 6

1) Air movement depends on changing the pressure inside the respiratory tract
a) Air flows from an area of higher pressure to an area of lower pressure
2) Air moves into or out of the Respiratory Tract based on changes in Thoracic Cavity Size (V) and Internal Pressure (P)

Question 7

What is Boyle’s Law?

Answer 7

P = I/V

Question 8

What happens to pressure when the volume of gas is increased?

Answer 8

Pressure decreases [Inhalation]

Question 9

What happens to pressure when the volume of gas is decreased?

Answer 9

Pressure increases [Exhalation]

Question 10

What is Compliance?

Answer 10

Indication of lung expandability

Question 11

What effect does Compliance have?

Answer 11

1) Higher Compliance = Easier Expansion

2) Lower Compliance = Harder to Expand

Question 12

What factors impact compliance?

Answer 12

1) Connective-Tissue structure
a) Emphysema results in supporting tissue damage and increases compliance
2) Surfactant
a) Decreased surfactant results in decreased compliance, as in Respiratory Distress Syndrome [RDS]
3) Mobility of Thoracic Cage
a) Skeletal disorders that affect ribs or spinal column can reduce compliance

Question 13

What is the Respiratory Cycle?

Answer 13

Single Inhalation and Exhalation.

Often measured as Tidal Volume [TV]

Question 14

What is Tidal Volume?

Answer 14

Amount of air moving into or out of your lungs during a single respiratory cycle

Question 15

What is Respiratory Rate?

Answer 15

of Breaths/min

Question 16

What is the Respiratory Minute Volume [VE]?

Answer 16

VE = Amount [volume] of air moved each minute
VE = RR * TV
Measure of Pulmonary ventilation

Question 17

What is Anatomic Dead Space [VD]?

Answer 17

Volume of air that remains in conducting pathways and does not enter the alveoli

Question 18

What is Alveolar Ventilation [VA]?

Answer 18

Amount of air reaching the alveoli each minute

Question 19

What happens in Gas Transport?

Answer 19

1) Oxygen binds to Haemoglobin [Hb] (1 Hb = 4x O2)

2) Each RBC has approx. 280 million Hb molecules

Question 20

What is Oxygen Saturation?

Answer 20

1) % of Haem units containing bound oxygen [termed Haemoglobin saturation]
2) Each time Hb molecule binds an O2 molecule, the change in shape enhances the ability to bind another O2 molecule

Question 21

What affect does pH on Respiration?

Answer 21

Active tissues generate acids that lower the pH of interstitial fluid:

1) As pH drops, Hb releases O2 and sats drop
2) Mostly due to CO2 in blood

Question 22

What affect does temperature have on Respiration?

Answer 22

Active tissues generate heat, causing Hb molecules to release more O2:
1) Mostly due to Skeletal muscle contractions warming the blood and organs