| Parameter | Unit | Equation |
|---|---|---|
| Oxygen delivery (DO2) | mL O2/min | DO2 = CO (L/min) × CaO2 (mL/dL) |
| Arterial oxygen content (CaO2) Venous oxygen content (CvO2) | mL O2/dL | CaO2 = 1.36 × Hgb (g/dL) × SaO2 (%) + [PaO2 × 0.003] CvO2 = 1.36 × Hgb (g/dL) × SvO2 (%) + [PvO2 × 0.003] |
| Blood flow, cardiac output (CO) | L/min | Flow = πr4
 P/8ηL |
| Oxygen consumption (VO2) | mL O2/min | VO2 = CO (L/min) × [CaO2 – CvO2] |
| Oxygen extraction ratio (O2EF) | percent | O2EF = [CaO2 – CvO2]/CaO2 × 100% or = VO2/DO2 × 100% |
P = change in pressure; η = viscosity; Hgb = hemoglobin; L = length of the vessel; PaO2 = partial pressure of oxygen in arterial blood; PvO2 = partial pressure of oxygen in venous blood; r = radius.