Evaluation of Fluid Responsiveness With Recruitment Maneuver After Sternotomy in Coronary Artery Bypass Surgery

In order to evaluate the fluid deficit in patients undergoing coronary artery bypass surgery, researchers will measure stroke volume index, cardiac index and mean arterial pressure while the patients are in the lima position. Then researchers will perform a lung opening maneuver (30mmHg for 30 seconds) and measure again. researchers will measure again after the values return to normal. researchers will give patients balanced fluid at 3ml/kg and record their values. Can researchers predict fluid response with lung opening maneuver?