Objective: To explore the detrimental influence of normothermic and hypothermic cardiopulmonary bypass during open heart surgery on cytokines and complements.
Method: Forty patients with congenital or rheumatic heart disease were randomized into 2 groups to receive normothermic cardiopulmonary bypass (CPB, study group, n=20) or hypothermic CPB (control group, n=20). Venous blood samples were respectively collected at scheduled time points preoperatively, at the end of CPB, and 1,4,7,14 d postoperatively to examine the level of interleukin (IL)-2, tumor necrosis factor (TNF)-alpha, C3, and C4.
Results: IL-2 in both groups decreased significantly at the end of CPB, postoperative day 1 and 4, but recovered the normal level at day 7 postoperatively. IL-2 in control group was significantly lower than that in the study group at each time points at the end of CPB and day 1 and 4 postoperatively. TNF-alpha in two groups was both elevated at the time points cited above, and in the study group, recovery of normal TNF-alpha level occurred at day 7 postoperatively, whereas in the control group, the recovery was not achieved until postoperative day 14. C3 in the study group was significantly lower at the time points of the end of CPB, day 1, 7 postoperatively than that in control group, but both elevated above normal at the end of CPB, day 1, and 4 postoperatively; in the study group, C3 became normal at day 7 postoperatively, which occurred in the control group only till day 14 postoperatively. At the end of CPB and day 1 postoperatively, C4 was significantly lower in the study group than in the control group, both below the level measured preoperatively at the time points of the end of CPB, day 1 and 4 postoperatively.
Conclusion: Open-heart surgery under normothermic CPB has less detrimental influence on cytokines and complements than the operation under hypothermic CPB for better recovery of the patient.