Abstract： Objective To investigate the effect of Shenfu injection on hemodynamics and systemic oxygen metabolism during off-pump coronary artery bypass grafting (OPCABG).Methods Fifty-six patients with coronary heart disease undergoing selective OPCABG (ASA Ⅱ -Ⅲ )were randomly assigned to Shenfu group (SF,n=29) and normal saline control group (NS,n=27).Patients in SF group received Shenfu 40 ml via intravenous injection prior to dermal preparation and graft anastamosis,respectively.In contrast,an equivalent volume of normal saline was injected in subjects of NS group.Hemodynamics and systemic oxygen metabolism was monitored using Swan-Ganz catheter,arterial and mixed venous blood gas analysis during anesthesia and surgery at nine time points of post anesthetic induction with stable hemodynamics (T1),after stemotomy (T2),before vascular anastomosis (T3),anterior drop branch anastomosis (T4),posterior descending artery or right coronary artery anastamosis(T5),left circumflex coronary artery or diagonal branch anastamosis (T6),cardiac at original position after vascular anastomosis (T7),before sternum closur(T8)and the end of operation(T9).Results Cardiac index (CI) and stroke index (SI) were significantly lower after posterior descending artery or right coronary artery anastamosis (T5) and left circumflex coronary artery or diagonal branch anastamosis (T6) as compared with post anesthetic induction with stable hemodynamics (T1)[(2.1 ±0.6) and (2.0 ±0.5) vs (2.3±0.5) L·min-1·m-2,(1.7 ±0.6) and (1.8 ±0.6) vs (2.1±0.5) L·min-1·m-2;(24±10) and (23 ±8) vs (32±7) ml·beat-1·m-2,(22 ±9) and (22 ±8) vs (32±9) ml·beat-1·m-2,P＜0.05].As compared with NS group,CI in SF group after sternotomy (T2) or T5 was slightly higher[ (2.5 ±0.7) vs (2.1 ±0.6) L·min-1·m-2,(2.1 ±0.6) vs (1.7 ±0.6) L·min-1·m-2,P＜0.05].During the operation,HR,MAP,LVWI and RVWI in SF group were slightly higher as compared with NS group (P＜0.05).pH decreased with time in both groups and was markedly lower in SF group compared with NS group (P＜0.05).During the operation,HCO3-,BE-E and TCO2 declined in both groups and had significant statistical difference (P＜0.05) at multiple time points.Oxygen delivery (DO2) was higher in SF group compared with NS group.No significant difference (P＞0.05) was found in VO2,O2ext and T during the operation in both groups.Conclusion During OPCABG in subjects with grade Ⅱ -Ⅲ ASA,intravenous Shenfu injection does not confer significant impact on hemodynamic and oxygen metabolism parameters with stable circulatory function and oxygen supply/consumption.