Formulas (Test 2)

Question 1

Compliance of the lungs

Answer 1

Question 2

Helium-dilution technique to find FRC

Answer 2

Or, C1 x V1 = C2(V2+FRC)

Question 3

Alveolar ventilation per minute

Answer 3

Question 4

Starling Capillary equation. Also name the pressures

Answer 4

Question 5

Inspired gas diluted by water vapor

Answer 5

Question 6

VE (minute ventilation)

Answer 6

Vt x RR

Question 7

Fick equation

Answer 7

Qt = cardiac output (L/min)

CaO2 - CvO2 = difference in oxygen content between arterial and mixed venous blood (Mls/Dl)

VO2 = O2 consumption by the body per minute (mls/min)

Aterial blood: 20 mlO2/dl (200ml/L)
Venous blood: 15 mlO2/dl (150ml/L)
5mlO2/dl/min released in tissues = 50ml/min of blood body needs

Question 8

Bohr equation: to determine physiological dead space

Answer 8

Vd / Vt = PaCO2 - PeCO2 / PaCO2 (answer is a ratio)

Answer x Vt = mls of dead space

Question 9

Oxygen content in the blood

Answer 9

(Hb x 1.34 x SaO2) + (PaO2 x 0.003)

1.34: binding capacity of hgb
0.003: O2 solubility increased plasma

Question 10

Volume at end of helium dilution technique

Answer 10

V2 = V1 x C1-C2 / C2