Sickle cell disorders are associated with increased risk of sickling and vaso-occlusive complications when undergoing cardiopulmonary bypass (CPB) surgery. Monitoring of certain parameters such as venous and arterial oxygen content, hematocrit, acid base homeostasis, and body temperature are required for a superior outcome. Furthermore, perioperative exchange transfusion has a positive effect on the outcome of surgery and on the survival of patients undergoing heart surgery. Avoiding intraoperative hypoxia and hypothermia, and minimizing hemoglobin S (HbS) and hemoglobin C (HbC) levels with exchange transfusion make bypass surgery relatively safe with enhanced outcomes in these cases. The exact HbS level for conducting cardiac surgery with CPB is not known, however, a HbS level