ABSTRACT
BACKGROUND: This study was prospectively designed to determine the physiologic effects of normothermic CPB and to compare its influences with hypothermic CPB. MATERIAL AND METHOD: Thirty-six adult patients scheduled for elective cardiac surgery were randomly assigned to moderate hypothermic (hypothermic group nasopharyngeal temperature 26~28 degreeC, n=18) or normothermic (normothermic group, nasopharyngeal temperature>35.5 degreeC, n=18) CPB. Arterial blood samples were taken before CPB (Pre-CPB), 10 minutes after the start of CPB (CPB-10), and immediately after CPB stop (CPB-off) for determining total leukocyte counts, neuron-specific enolase (NSE), interleukin-6 (IL-6), endothelin-1 (ET-1), cortisol, troponin I (TNI), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, blood urea nitrogen (BUN), and the pulmonary index (PI, PaO2/FiO2). Other parameters such as urine output, mechanical ventilating period, ICU-staying period, postoperative complications and hospitalized days were also evaluated. RESULT: Total leukocyte counts, increased rate in NSE, in IL-6 and in cortisol at CPB-10 and CPB-off were significantly higher in normothermic group than in hyphothermic group. Urine output during CPB was lower in normothermic group than in hyphothermic group. The duration of mechanical ventilation, ICU-stay, and hospitalization were longer in normothermic group than in hyphothermic group. CONCLUSION: These findings suggested that normothermic CPB caused higher inflammatory and stress responses than hypothermic CPB during cardiac surgery using cold crystalloid cardioplegia. However, further studies with large number of cases should be carried out to validate this hypothesis.