physiology- resp ventilation & gas exchange

Question 1

Pulmonary Minute Ventilation

Answer 1

total volume of air entering and leaving respiratory system per min

Question 2

Alveolar Ventilation

Answer 2

volume of air exchanged between the atmosphere and alveoli per min

Question 3

Respiratory Diseases

• Two main classifications

Answer 3

• obstructive

- restrictive

Question 4

obstructive

Answer 4

decreased air flow during expiration
airway narrowing
increased airway resistance

example asthma , chronic bronchitis

Question 5

restrictive

Answer 5

reduced compliance , lung volume
scar tissue forming
fibrosis
example : pulmonary fiborsis

Question 6

asthma what happens
it causes
symptoms

Answer 6

when bronchi are hyper sensitive to dust , pollutants ect

chronic inflammation which leads to excess production of mucous and airway narrowing

breathlessness , tightness in chest , coughing

Question 7

asthma caused by

Answer 7

• alleregns
• smoking , airborne pollutants
• changes in air temp and pressure
• excersize
• anxiety , emotional distress

Question 8

asthma treatment

Answer 8

bronchodilators , anti - inflammatory , 02

Question 9

chronic bronchitis
what
symptoms

Answer 9

inflammation of airway walls

excessive mucous production
airway narrowing and coughing

Question 10

chronic bronchitis : caused by

Answer 10

bacterial and viral infections
smoking
airborne pollutant

Question 11

Pulmonary fibrosis

what happens when you have it

Answer 11

↓ elasticity
↓ compliance of lungs and chest wall
↑work of breathing

Question 12

pulmonary fibrosis

caused by

Answer 12

inflammation

scar tissue formation

Question 13

NEW LECTURE : GAS EXCHANGE

Answer 13

……..

Question 14

what is partial pressures of gases

Answer 14

the pressure exerted by a individual gas in a mixture

Question 15

Partial pressure of a gas depends on:

Answer 15

fractional component of gas

total pressure of gas mixture

Question 16

Composition of Air

Answer 16

79% nitrogen
21% oxygen
trace amounts of c02 , helium , argon
water % depends of humidity

Question 17

Ficks law - rate of diffusion

Answer 17

Vgas= A/T x D⋅(ΔP)

Question 18

Vgas= A/T x D⋅(ΔP)

D∝ S / square root of MW

Answer 18

Vgas= rate of diffusion
A= surface area
T=thickness
D= diffusion constant
ΔP=pressure difference

S= gas solubility 24:1
MW= molecular weight 44:32

Question 19

surface area

Answer 19

increases during excersize… more pulmonary capillaries open and aveoli expands

50-100cm in lung

Question 20

Equilibration rates
02 and c02 rates
at rest
during intense excersiz

Answer 20

• 02 and c02 equilibrate at similar rates
• blood spends 0.75 secs in a capillary
• 0.25 secs

Question 21

Diffusion process affected by:

Answer 21

excersize

thickening of blood gas barrier

Question 22

Pulmonary Oedema
what is it
what does it do

Answer 22

-fluid accumlation in alveoli and /or interstitial fluid

• impairs diffusion
• leakage in unprotected capillaries
• increased work of breathing (decrease in lung compliance)
• artierol blood : lower P02 , higher PC02

Question 23

Pulmonary Oedema
caused by
treatment

Answer 23

increased capillary pressure and reduced atmospheric pressure

Administering oxygen and diuretics