Abstract: ［Abstract］〓Objective〖HTSS〗〓To investigate the effects of dexmedetomidine on inflammatory response, insulin resistance and myocardial injury caused by lower limb tourniquet surgery in diabetic patients.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓According to random data table method, a total of 60 diabetic patients who were accepted lower limb orthopedic surgery were divided into observation group and the control group, 30 cases in each group. In observation group，dexmedetomidine 1 μg/kg (initial dose) was given(15 min) after induction of anesthesia，followed by continuous infusion at 0.5 μg·kg-1·h-1, until the end of operation. The equal volume of normal saline was given instead of dexmedetomidine in the control group．Before the tourniquet(T0), after loose tourniquet 15 min(T1), after loose tourniquet 1 h(T2) and after loose tourniquet 12 h(T3), blood samples were collected for determination of tumor necrosis factor α(TNFα), interleukin 6(IL6), blood glucose and insulin, cardiac troponin I(cTnI) and phosphoric acid creatine kinase isoenzyme(CKMB) concentrations. The insulin sensitivity index(ISI) was obtained．
〖HTH〗〖WTHZ〗Results〖HTSS〗〓The concentration of TNFα、blood glucose and insulin in the two groups were firstly increased and then decreased, while the levels of IL6, cTnI and CKMB were gradually increased, all indexes of the observation group were lower than those of the control group, there were statistically significant differences between groups, time points and their interactions(P＜005). The SIS were gradually decreased in the two groups, and the observation group was higher than the control group, there were statistically significant differences between groups and time points(P＜005), while there was no significant difference between their interactions(P＞005).
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓Dexmedetomidine can reduce the inflammatory response, alleviate myocardial injury caused by lower limb tourniquet surgery, thus reducing blood glucose and insulin resistance in diabetic patients.

Key words: diabetes mellitus, type 2； dexmedetomidine, tourniquets