The Effect of 6% Hydroxyethyl Starch 130/0.4 on Blood Loss and Coagulation in Patients Medicated With Antiplatelet Agents Prior to Off-Pump Coronary Bypass Graft Surgery

Inclusion Criteria: * Eighty patients undergoing OPCAB, who were exposed to anti platelet agents until 5 days prior to surgery were randomly allocated to infuse HES 130/0.4 up to 30 ml/kg and followed crystalloid infusion or infuse crystalloid only during perioperative period, Exclusion Criteria: Patient who has * Valvular disease of heart * MI within 3 months,patient under 40% of left ventricle preoperative output * left main artery stenosis * anemia (hemoglobin \< 12 g/dl), coagulopathy (Platelet \< 100/nl, activated partial thromboplastin time, aPTT) \> 80sec, serum creatinine \> 1.2 mg/dl, respiratory disease(asthma, COPD, PaO2 \< 70 mmHg, pulmonary hypertension or pulmonary edema, etc) * not consented to this trial