European Journal of Cardiovascular Medicine

Introduction: OPCAB was designed to reduce complications resulting from cardiopulmonary bypass like stroke, renal complications and myocardial ischemia and to reduce hospital stay, reduce morbidity and mortality. It includes various anatomical distortions of heart using stabilizers and suspensions which needs extensive monitoring techniques. To improve its efficiency neurological monitoring like NIRS and PA cannulation could play a significant role in further reducing such complications. Mixed venous oxygen saturation (SvO2) remains the accepted standard during anesthesia to evaluate the balance of oxygen delivery and consumption, especially during cardiac surgery. Monitoring the ScvO2-SvO2 with conventional PAC gives indirect evidence of myocardial ischemia, after excluding other causes of ischemia in lower body. Materials and Methods:  In this single centred prospective interventional study, 60 patients undergoing elective off pump CABG between March 2018 to March 2020 were taken. Institutional ethical and scientific committee approval was taken (UNMICRC/ANESTH/2017/09) and written informed consent from patients was obtained. Results:  Total 360 patients were enrolled in the study for comparative analysis of regional cerebral oxygen saturation (rScO2), central venous oxygen saturation (ScvO2) and mixed venous oxygen saturation (SvO2) in off pump CABG. Table 1 shows general characteristics of patients. Mean ejection fraction was 45.92 ± 9.23%. Fifty patients had triple vessel disease and 10 had double vessel disease for which 60, 53 and 49 patients had undergone Left anterior descending (LAD), Obtuse marginal (OM) or Diagonal (DG) and Posterior descending artery (PDA) or Right coronary artery (RCA) grafting respectively. Conclusion:  Positioning of the heart for distal anastomoses at lateral and posterior wall was associated with more hemodynamic alteration and increased in inotropic and vasopressor requirement and significant decreased in rScO2, ScvO2 and SvO2. There was significant positive correlation on measured gradient between ScvO2 & SvO2 and rScO2 & SvO2 and rScO2 & ScvO2. ΔrScO2 was found to be highest as compared to ΔSvO2 followed by ΔScvO2.