- no ITPR .Anesthesia will be standardized for both groups. The groups will be compared based on the differences in vasopressor use, the number and amount (in milliliters) of intravenous fluid boluses required and hemodynamic changes noted, including systemic blood pressure, pulmonary arterial pressure, pulse pressure, heart rate (recorded most reliably from the arterial line), cardiac output (CO), cardiac index (CI), mixed venous oxygen saturation (SVO2), SVR, pulmonary vascular resistance (PVR), and stroke volume (SV).