Review-Johnson

Question 1

Difference between obstructive and restrictive

Answer 1

obstructive–> time factor: takes longer

restrictive–> huge reduction in lung capacity so all the volumes go down

Question 2

peripheral chemoreceptors

Answer 2

uniquely sensitive to low levels of O2–they detect hypoxia; also respond to pH an dCO2 concentration; this is the backup system for when you lose ability to sense CO2

Question 3

PO2 should be 100 mmHg but if less than this, you will get a huge stimulation sent to the integration center

Answer 3

60 mmHg

Question 4

Process

Answer 4

-low level of O2 will cause stimulation of peripheral chemoreceptors
-as a result you have a n increase in ventilation
more O2 comes in and as a result plasma O2 rises above the 60 and as you approach 100 you have less stimulation going towards the CNS and you have a decrease in vent back to normal ventilation

-you have a negative feedback system that will eventually stop the stimulation of peripheral chemoreceptors

Question 5

CO2 increases during apneic pause in the arterial blood and in the CSF

Answer 5

through carbonic acid equation

Question 6

central chemoreceptor

Answer 6

• only respond to CO2 via the hydrogen ions that get into CSF
• is insensitive to O2
• used on a breath to breath basis

Question 7

Know the partial pressures in the arterial blood, alveolar air, mixed venous blood, tissues ??

Answer 7

Alveolar Air: 100 of PO2, 40 for PCO2

Arterial blood: 100 for PO2, 40 for PCO2

Mixed Venous Blood: 40 for PO2, 46 for PCO2

Tissues: 40 for PO2, 46 for PCO2

Question 8

central pattern generator

Answer 8

preboxing complex

Question 9

increase in pH, become alkaline

Answer 9

inhibits ventilation, slow down breathing rate

Question 10

How do you override the central pattern generator?

Answer 10

when you dive and go swimming, holding breath

Johnny starts breathing and CO2 is going to shoot over the roof and body will override his effort to hold his breath

Voluntary control (higher brain centers)
Competes with involuntary mechanisms.
Demonstrated with breath holding
Automatic eventually overpowers the voluntary efforts thereby limiting the duration of the breath

Question 11

Go over Mechanics !!!

Answer 11

puts alveolar volume interpleural pressure
airflow
understand the relationship of what is happening

slides to giving multiple principles on charts

Question 12

four volumes

Answer 12

TV
IRV
ERV
RV

Question 13

four capacity

Answer 13

TLC
FRC
IC
VC: (FVC is the test -forced vital capacity; involves inspiration and expiration)

Question 14

What is the difference between FVC and VC?

Answer 14

FVC is
VC is

the volume of air is the same the FVC just forces the air out more quickly

FEV1 is the amount of air you can get out in the first second, FVC is total amount and if it is around 80% then its normal

Question 15

Know spirometer

Answer 15

can only detect volumes that can enter the spirometer

No calculations on the exam

cannot measure residual volume

Question 16

Pulmonary gas exchange is dependent on which law?

Answer 16

Fick’s law of diffusion. Diffusion occurs in response to a concentration gradient expressed as the change in concentration due to a change in position

Question 17

What is the Haldane effect?

Answer 17

left shift
-CO2 transport
-when O2 binds to Hb it forces CO2 to be displaced
allowing for 2% more of CO2 to be liberated

CO2 loading into the blood is facilitated by decreases in oxyhemoglobin saturation (Haldane effect)

Question 18

What is the Bohr effect?

Answer 18

right shift
O2 unloading within the systemic capillary is enhanced by increases in PCO2 and by reduced pH (Bohr effect)

• increase temp
• increase [H] AKA decrease pH
• increase CO2
• increase 2,3 DPG

Question 19

Methods of transport for CO2 and O2 and which are the most effective

Answer 19

O2 has 2 methods

• Hb (98%)
• plasma (2%)

CO2 has 3 methods

• Hb (23%)
• plasma (7%)
• bicarbonate (70%)

Question 20

Know how to calculate partial pressure so you know which way

Answer 20

???

Question 21

Graph

Answer 21

20 mech
12 gas exchange
6 for SGL
6 for simulation

6 questions per lecture

Question 22

changes in alveolar and pleural pressure, expiratory flow, and lung volume during a tidal volume breath

slide 40 of mechanics I

Answer 22

inspiration is to the left of the vertical dotted and exhalation is to the right

positive (relative to atmosphere) pressures are below

at points of no airflow (A, c