UWorld Pulmonary Phsyiology

Question 1

At altitude for 2+ days.  What would you levels be compared to normal:
PaO2
PaCO2
plasma HCO3
pH

Answer 1

PaO2 decreased (this hypoxia triggers hyperventilation)
PaCO2 decreased
plasma HCO3 decreased (metabolic compensation for low CO2)
pH increased

you are in respiratory alkalosis

Question 2

Name the factors that induce a right shift.

Answer 2

Decreased O2 affinity
pH decrease
2,3 BPG increase
Temp increase
PCO2 increase

Question 3

Name factors that induce a left shift

Answer 3

Increased affinity for O2
pH increase
PCO2 decrease
2,3 BPG decrease
Temp decrease

Question 4

What happens to V/Q, gas exchanges, PO2, PCO2, and A-a gradient in airway obstruction?

Answer 4

V=0, so V/Q = 0
gas exchange = 0
PO2 and PCO2 of pulmonary capillary blood approaches systemic.
A-a gradient is increased

Question 5

What happens to V/Q, gas exchange, PAO2, PACO2.

Answer 5

Q=0, so V/Q = infinity
gas exchange = 0
PAO2 and PACO2 approach values of inspired air.

Question 6

During excercies, what changes occur in:
O2 consumption
CO2 consumption
Ventilation rate
arterioal PO2 and PCO2
Arterial pH (moderate excercise v. strenuous exercise)
venous PCO2
pumonary blood flow
V/Q ratios

Answer 6

incr
incr
incr (matches O2 consupmtion/CO2 production)
no change
no change in moderate, decrease in strenuous (lactic acidosis)
incr
incr
more evenly distribute in lung

Question 7

Name the location of central chemoreceptors and the stimuli that will increase breathing rate

Answer 7

located in medulla, responds to increased CO2/decreased pH in CSF

Question 8

Name the location of peripheral chemoreceptors and the stimuli that will increase breathing rate.

Answer 8

carotid and aortic bodies. respond to decreased pO2 (

Question 9

normal sweat gland channels v. CF

Answer 9

Cl and Na into epithelial cell (out of sweat). In CF, there is a lack of Cl-channel, so there is a loss of Na and Cl in sweat causing hypoNa

Question 10

PaO2, arterial oxygen saturation (SaO2), and oxygen content in:
CO poisoning

Answer 10

normal
decreased
decreased

Question 11

Cyanide poisoning

Answer 11

normal
normal
normal

Question 12

anemia (decr Hb) v. polycythemia (incr Hb)

Answer 12

normal normal decreased

v

normla normal normal increased

Question 13

high altutide

Answer 13

decr
decr
decr

Question 14

hypoxia due to diffusion limitations occurs in what disease

Answer 14

fibrosis

Question 15

what lung disease has decreased rate of breathing and increased tidal volume

Answer 15

obstructive (COPD, asthma) to decrease work of breathing due to increased airflow resistance

Question 16

what lung disease has a high respiratory rate and low tidal volume

Answer 16

restrictive (pulmonary fibrosis) to minimize work of breathing due to loss of elastance

Question 17

What obstructive lung disease has increased pulmonary compliance, FRC and TLC?

Answer 17

COPD - hyperinflated lungs (barrel chest)

emphysema FRC and TLC&raquo_space;> chronic bronchitis

Question 18

what obstructive lung disease has decreased carbon monoxide diffusion capacity?

Answer 18

emphysema

Question 19

Why is sputum on strep pneumo green?

Answer 19

Due to MPO, a blue-green heme-based enzyme released from azurophilic neutrphil granules, that forms hypochlorous acid (bleach)

Question 20

diffuse small nodules with hilar calcifications

Answer 20

silicosis (think gold mine)