The Impact of Cardiac Surgery with Deep Hypothermic Circulatory Arrest on Systemic Inflammatory Response and Postoperative Morbidity in Adults

ABSTRACT

BACKGROUND: The inflammatory response to cardiopulmonary bypass (CPB) surgery is believed to play an important role in the end organ dysfunction after open heart surgery. The effect of temperature on the post-bypass inflammatory response has been studied in normothermic and hypothermic patients. This study compared the influence on the systemic inflammatory response and postoperative morbidity in hypothermic cardiopulmonary bypass patients with those in patients in deep hypothermic circulatory arrest. METHODS: Fifty patients undergoing elective redo-valvular replacement or double valve replacement using a hypothermic cardiopulmonary bypass (26-28oC, H Group) and 9 patients undergoing an elective ascending aortic aneurysm replacement using deep hypothermic circulatory arrest (16oC, D Group) were prospectively investigated. The serum samples were collected to estimate the interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha levels immediately after induction, 30 min after the initiation of the CPB, 30 min after weaning from the CPB, 2 hours after the CPB, 24 hours after the CPB. RESULTS: Patients preoperative and intraoperative characteristics (age, gender, aortic cross clamping time, cardiopulmonary bypass time) were not similar in the two groups. The serum level of IL-6 and TNF-alpha were also similar in the two groups. There were no statistical differences in the intubation time, ICU stay and oxygenation index (arterial PO2/inspired fraction of oxygen). There were also no statistical differences in the incidence of systemic inflammatory response syndrome and the APACHE II scores. CONCLUSIONS: Deep hypothermic circulatory arrest was not shown to produce a more profound inflammatory response or influence the postoperative morbidity than a hypothermic cardiopulmonary bypass.