ABSTRACT Objective: To summarize the effect of mild hypothermia on function of the organs in patients with multiple organ dysfunction syndrome after cardiopulmonary bypass surgery. Methods: The patients were randomly divided into two groups, northermia group (n=71) and hypothermia group (n=89). We immediately began cooling the hypothermia group when test results showed multiple organ dysfunction syndrome, meanwhile all patients of two groups were drawn blood to test blood gas, liver and kidney function, blood coagulation function, and evaluated the cardiac function using echocardiography from 12 to 36 hours. We compared the difference of intra-aortic balloon pump, extracorporeal membrane oxygenation rate and mortality within one month after intensive care unit admission. Results: Among the 160 patients, 36 died, 10 (11.24%) patients were from the hypothermia group and 26 (36.6%) from the northermia group (P <0.05). In northermia group, 45 (63.38%) patients used intra-aortic balloon pump and 4 (5.63%), extracorporeal membrane oxygenation; in hypothermia group, 35 (39.32%) patients used intra-aortic balloon pump and 2 (2.25%), extracorporeal membrane oxygenation（ P <0.05). The patients' heart rate decreased significantly in the hypothermia group. The heart rate of hypothermia group is significantly slower than the northermia group at the 36th hour (P <0.05). But the mean arterial pressure of hypothermia group is significantly higher than the northermia group at the 36th hour (P <0.05). In hypothermia group, PO2, SvO2 and lactate were improved significantly compared to pre-cooling (P <0.05), and they were significantly better than the northermia group at the 36th hour (P <0.05%). Prothrombin time and activated partial thromboplastin time have no significantly difference between the two groups (P >0.05). But the platelet count has significantly difference between the two groups at the 36th hour (P <0.05). The aspartate transaminase, alanine transaminase and creatinine were improved significantly in the hypothermia group, and they were significantly better than the northermia group (P <0.05). Conclusion: Mild hypothermia is feasible and safe for patients with multiple organ dysfunction syndrome after cardiopulmonary bypass surgery.

Abstract Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are reverse voltage-dependent, and their activation depends on the hyperpolarization of the membrane and may be directly or indirectly regulated by the cyclic adenosine monophosphate (cAMP) or other signal-transduction cascades. The distribution, quantity and activation states of HCN channels differ in tissues throughout the body. Evidence exhibits that HCN channels play critical roles in the generation and conduction of the electrical impulse and the physiopathological process of some cardiac diseases. They may constitute promising drug targets in the treatment of these cardiac diseases. Pharmacological treatment targeting HCN channels is of benefit to these cardiac conditions.