Goal Directed Therapy Aiming to Optimise Oxygen Central Venous Saturation in Children Undergoing Cardiac Surgery

Central venous oxygen saturation will be targeted higher than 65% in non-cyanogenic patients and 55% in cyanogenic. * First, isotonic crystalloid, 10 up to 20 mL/kg, will be administered in boluses to achieve continuous central venous oxygen saturation higher than 65% in non-cyanogenic and 55% in cyanogenic. * Second, if not achieved with fluid administration, will be targeted by initiating and titrating inotropics (dobutamine or milrinone). If the mean arterial pressure is lower than 50 mm Hg will be associated epinephrine. * If the ScvO2 is lower than 65% in non-cyanogenic and 55% in cyanogenic and the hemoglobin was lower than 8g/dl, red blood cells (20mL/Kg) will be transfused to achieve a hemoglobin level of at least 8g/dL.

The control group will keep the standard therapy to achieve mean arterial pressure higher than 50mmHg, central venous pressure 8 to 12 mmHg, urinay debit higher than 0,5ml/kg/h, hemoglobin higher or equal than 8g/dL, arterial oxygen saturation higher or equal than 92% in non-cyanogenic and 80% cyanogenic, central venous oxygen saturation higher or equal than 65% in non-cyanogenic and 55% in cyanogenic.