Lung Physiology 1 and 2

Question 1

Structures which contribute to respiratory pump?

Answer 1

1) Bones (Ribs and sternum)
2) Muscles (Diaphragm and IC’s)
3) Pleura
4) Nerves

Question 2

What nerves are the diaphragm innervated by?

Answer 2

C3,4,5

Question 3

Define dead space?

Answer 3

Where air is supplied, but no GE occurs

Question 4

What does ventilation allow for?

Answer 4

Bulk flow in airways

1) O2/CO2 movement

Question 5

What is perfusion and specific to lungs?

Answer 5

1) Blood supply

2) Pulmonary blood supply i.e. P arteries

Question 6

What is a V/Q mismatch?

Answer 6

Perfusion of blood in capillaries doesn’t match alveoli ventilation

Question 7

What is Pulmonary capillary perfusion dependent on? (3)

Answer 7

1) Alveolar pressure
2) PA pressure
3) PV pressure

Question 8

What is hypoxic pulmonary constriction?

Answer 8

Constriction of vasculature, means O2 not delivered to dependent points in lungs

Question 9

Distinguish differences in Respiratory Nomenclature (4)

Answer 9

1) Pa is arterial pressure
2) PA is alveolar pressure
3) Pi is inspired pressure
4) v̇ w/ (A= Alv vent) [CO2 is CO2 prod]

Question 10

What causes ODC shift to right and meaning?

Answer 10

1) Increase in Temp, decrease in pH

2) Increased o2 dissociation, so affinity decreased

Question 11

What are 7 layers for gas exchange?

Answer 11

1) Alveolar Epithelium
2) Interstitial Fluid
3) Capillary Endothelium
4) Plasma Layer
5) RBC Membrane
6) RBC Cytoplasm
7) HB Binding sites

Question 12

What is the alveolar gas equation?

Answer 12

PAO2 = PiO2 - (PaCO2/R)

Question 13

Enzyme catalysing formation of HCO3- and H+ from CO2 and H2O?

Answer 13

Carbonic Anhydrase

Question 14

What is the acid/base dissociation equation?

Answer 14

CO2 + H2O = H2CO3 = HCO3- + H+

Question 15

Name the HH equation

Answer 15

pH= pKA + log (A-)/(HA)

Question 16

What causes respiratory acidosis and alkalosis?

Answer 16

1) Ac: Inadequate ventilation

2) Alk: Hyperventilating due to Hypoxia

Question 17

Renal compensation mechanism for R acidosis/alkalosis?

Answer 17

1) ^NH3 formed, H+^ secretion, so more HCO3- reabsorbed

2) H+V sec, so more H+ retained, less HCO3- reabsorbed

Question 18

What causes metabolic acidosis and alkalosis?

Answer 18

1) Ac: Renal failure (VHCO3-, XS H+ prod)

2) Al: Vomiting (Loss of H+)

Question 19

Respiratory compensation for each metabolic?

Answer 19

1) CR stim, enhance resp, PaCO2 V

2) CR inhib, V insp, PaCO2 ^

Question 20

Define FVC

Answer 20

Max vol of air forcibly exhaled after max in

Question 21

Define FEV1

Answer 21

Max forced vol of air in 1 second

Question 22

Define TLC and how calculate?

Answer 22

1) Full capacity of lungs

2) Vital capacity + Residual volume

Question 23

Define Peak flow

Answer 23

Greatest rate of airflow that can be obtained during forced exhalation

Question 24

What is lung compliance?

Answer 24

Measure of lungs ability to stretch and expand

Compliance = ∆V/∆P.

Question 25

What is DLCO?

Answer 25

Uptake of CO in ml at standard T and Pa

Question 26

Why is CO used to estimate DLCO?

Answer 26

High affinity to bind to HB

Question 27

What does DLCO show?

Answer 27

Ability of lung to transfer gas into blood stream from inhaled air