Effects of Methylprednisolone Combined with Dexmedetomidine on Cognitive Function under Cardiopulmonary Bypass / 医学研究杂志

ABSTRACT

Objective To evaluate the protective effects of methylprednisolone combined with dexmedetomidine of cardiac valve replacement in patients with brain cognitive function under cardiopulmonary bypass (CPB).Methods Sixty patients for heart valve replacement in Affiliated Hospital.Inner Mongolia Medical University were randomly divided into four groups (n =15 each):group A control,methylprednisolone group (group M),dexmedetomidine group (Group D) and methylprednisolone combined with dexmedetomidine group (group B).After the induction of anesthesia,the patients were endotracheally intubated and mechanically ventilated.Methylprednisolone 20mg/kg was administered to the CPB circuit prime in group M.A loading dose of dexmedetomidine 1 μg/kg was pumped intravenously over 10 minutes after induction,followed by continuous infusion at 0.05μg/(kg · h) until the end of operation in group D.A loading dose of dexmedetomidine 1 μg/kg was pumped intravenously over 10 minutes after induction,followed by continuous infusion at 0.05μ g/(kg · h) until the end of operation and methylprednisolone 20mg/kg was also administered to the CPB circuit prime in group B.At the same time the equal volume of normal saline was given in group A.After induction (T1),CPB instantly (T2),CPB 30min (T3),l0min after CPB(T4),at the end of operation(T5),6h after CPB (T6),the jugular bulb venous blood samples were taken for testing the serum concentrations of interleukin-6 (IL-6),interleukin-10 (IL-10),S100βprotein and neuron-specific enolase (NSE) using the method of ELISA.Simplified mini-mental state examination (MMSE) is used to assess the cognitive function of patients in pre-operation and 2days,3days as well as 7days after operation.Results At T1-6,IL-6,S100 protein and NSE in group M,group D and group B were significantly lower than those in control group,IL-10 was higher than that in control group,and there was significant difference (P ＜ 0.05).In B group at all time points IL-6 、S100 protein and NSE were lower than those in other groups,IL-10 was higher than other groups,and there was significant differences (P ＜ 0.05).The incidence of postoperative cognitive dysfunction in group M,group D and group B was higher than that in control group,and the incidence of cognitive dysfunction in B group was lowest,and there were significant differences (P ＜ 0.05).Conclusion Methylprednisolone and dexmedetomidine can effectively reduce the concentration of IL-6,S100 protein and NSE in cardiopulmonary bypass,reduce brain injury and the incidence of postoperative cognitive dysfunction.The protective effect on cerebral injury is better when using dexmedetomidine combined with methylprednisolone under cardiopulmonary bypass (CPB).