# Equations Flashcards

What is the alveolar gas equation?

**PAO _{2} = PIO_{2} – (PaCO_{2} * 1.2)**

What is the equation for air inspired when breathing at KU?

PIO2 = (PB-47)*0.21 = 147 mm Hg

What is the equation for total blood O2 content?

Hb *1.34 * % saturation + (0.003*PO2)

What is the equation for Dead Space/Tidal volume?

(PaCO2 – PECO2) / PaCO2

What is the equation for compliance?

∆ Lung volume /∆PTP

What is the equation for airway resistance?

(PB - PALV) / airflow

What is the equation for O_{2} saturation of Hb (%)?

O_{2} saturation of Hb (%) = [(HbO2,ml/dl / (Hb, g/dl * 1.34 ml/g)] x 100

What is the equation for blood O_{2} content?

Blood [O2] content, ml/dl = [0.003 ml/(mmHg x dl) x PO2 (mmHg)] + [Hb] g/dl x 1.34 ml/g x % O2 sat]

Calculate and insert the remaining values

What is the equation for VO_{2}?

VO2 = Q * C(a-v) O_{2}

Q, cardiac output

C (a-v) O2, difference in arterial and venous O_{2} content

What is the equation for oxygen extraction ratio (O_{2}ER)?

O_{2}ER- C (a-v) O_{2}/ CaO_{2}

What is the equation for the pressure produced by a single gas?

Find the partial pressures of gases a and b given that the Ptotal is 100 mm Hg; a, n=6 and b, n=14.

What is the equation for the diffusion of a substance across a membrane?

What is the equation for difussion capacity?