Acute Normovolemic Hemodilution in High Risk Cardiac Surgery Patients.

Exclusion Criteria

• •Medical decision (e.g.: planned pre-CPB ANH considered undeniable for ethical reasons or not applicable for safety issues)
• •Unstable Coronary Artery Disease: Recent (\< 6 weeks) myocardial infarction, unstable angina, severe (\> 70%) left main coronary artery stenosis
• •Critical preoperative state (ventricular tachycardia or ventricular fibrillation or aborted sudden death, preoperative cardiac massage, preoperative ventilation before anesthetic room, hemodynamic instability, preoperative inotropes or IABP, preoperative severe acute renal failure (anuria or oliguria \<10ml/hr.)
• •Emergency surgery
• •Pregnancy
• •Unfeasibility to withdraw ≥ 650 ml without inducing hemodynamic instability
• •Unfeasibility to withdraw ≥ 650 ml without inducing pre-CPB anemia (Htc \<30%)
• •Unfeasibility to withdraw ≥ 650 ml without inducing low Htc during CPB (Htc \<24%)