Cardiac Output (CO) is the amount of blood pumped by the ventricles each minute. It is the product of Heart Rate (HR) and Stroke Volume (the amount of blood ejected by the ventricle with each contraction).
CO=HR x SV
Normal C.O. = 4-8 L/min
* These values are relative to size*- What may be normal for a 5ft tall 80 yo 40 kg woman may be totally inadequate for a 6 ft 100kg man. So we use Cardiac Index to adjust to individual body size.
Cardiac Index = CO/the person's Body Surface Area