Siemens ACUSON Cypress Operator's Manual page 167

Doppler Formulas (Cardiac)
TABLE 31.
Type Formula
Shunt Ratio
Qp
------ -
Qs
CO
CO
Shunt
Qp Qs
Difference
CO
CO
ACUSON Cypress™ Operator's Manual
CO
Qp
= --------------
CO
Qs
is pulmonic Cardiac Output (l/min).
Qp
is systemic Cardiac Output (l/min).
Qs
– = CO – CO
Qp Qs
is pulmonic Cardiac Output (l/min).
Qp
is systemic Cardiac Output (l/min).
Qs
Cardiac Formulas and References
Units
—
l/min
6-23