Single-centre prospective randomized study will be included the patients who undergo elective cardiovascular surgery. Preoperative fluid deficit will be calculated by the formula as starvation period X 4 X weight. Patients will be divided into two groups: Group A (n=20); crystalloid as priming solution used in patients, Group B (n=20); colloids as priming solution used in patients. In addition to priming solutions, extracorporeal pump will be filled with 150 mL of Mannitol, 60 mL of NaHCO3 and 10000 IU Insulin. Standard anesthesia protocol will be administered to all patients. Ringer's Lactate will be given at first 30 minute after induction. Ringer's Lactate as fluid maintenance will be administered at a rate of 100 mL/h except in extracorporeal circulation. Goal-directed fluid management will be performed by PVI (Pleth Variability Index). Cut off level of PVI will be accepted %15.

For integrative investigation of the effects of priming solution and postoperative fluid management on the complex interrelation between microcirculation and reactive oxygen species; sublingual microcirculation using microcirculation imaging system (IDF, Cytocam, NL) will be displayed and measure ekstra vascular lung water (EVLW) using PiCCO and plasma levels of oxidative stress markers will be measured. Sublingual tissue microcirculation will be evaluated in all patients at different time points as before induction (T0), after induction (T1), before cross clamping-hypothermic period (T2), after cross clamping (T3), before end of pump (normothermic period, heating) (T4), acceptance to intensive care unit (T5), third hour after surgery (T6) and twenty forth hour after surgery (T7).

Inclusion Criteria:

• cardiovascular surgery needed

Exclusion Criteria:

• no informed consent