Liberal Versus Restrictive Use of Dobutamine in Cardiac Surgery

All patients will receive dobutamine at the cardiopulmonary bypass weaning.

Patients will receive dobutamine during the first 8 hours after cardiopulmonary bypass weaning only if they have a cardiac index of ≤ 2.5L/min/m2 and at least one sign of tissue hypoperfusion: ScvO2 ≤ 70% and / or urine output \< 2 mL/Kg/h despite adequate fluid replacement.