Cardiac Output Monitoring With Estimated Continuous Cardiac Output (esCCO) vs. Transpulmonary Thermodilution (TPTD)

After the end of surgery in ICU the positive end-expiratory pressure (PEEP) test of 15 cm H2O for 300 seconds will be performed. Following PEEP test, the two-step fluid load test of 6 ml/kg balanced crystalloid solution will be performed sharing in two portions: Initial mini FLT (mFLT) of 1.5 ml/kg within 1 min (approximately 100 mL) followed by the registration of continuous CI and traditional fluid responsiveness parameters and the rest of standard FLT (4.5 mL/kg) within 5 minutes (approximately 350 mL) followed by transpulmonary thermodilution, registration of continuous cardiac index (CI) and classic fluid responsiveness parameters.