Effect Of Dexmedetomidine Hydrochloride On Metabolism Of Tissue During Cardiopulmonary Bypass

Objective:the research through monitor the change of plasma Lactate、Plasmaglucose and the tissue oxygen metabolism to explore whether DexmedetomidineHydrochloride restrain the tissue metabolism during in cardiopulmonary bypass(CPB).Methods:30patients, aged40-70years old with cardiac function2-3degree.According to New York Heart Association (NYHA) and undergoing cardiac surgery viaCPB, were randomly assigned to two groups, Conventional general Anesthesia group(A group n=15), and Dexmedetomidine Hydrochloride Pretreated anesthesia group (Bgroup n=15). All the selected patients were without cerebrovascular and neurologicaldiseases or serious liver and kidney dysfunction.Conventional general anesthesia groupwas infused with saline0.125ml/kg/h in ten minutes before induction,Dexmedetomidine Hydrochloride Pretreated anesthesia group was infuse with ivinjection Dexmedetomidine Hydrochloride0.125ml/kg/h(4ug/ml) in ten minutes beforeinduction;two groups was induced with midazolam0.05-0.1mg/kg, fentanyl l10μg/kg,etomidate0.2-0.3mg/kg, cisatracurium0.2mg/kg. Anesthesia maintained: After trachealintubation,1%propofol6-8mg/kg/h and fentanyl10μg/kg Constantly infused beforestenotomy. According to surgical procedure, two groups of patients were injected withmidazolam and cisatracurium. The blood samples were collected respectively fromradial artery and the right of jugular vein or extracorporeal circulation machine forblood gas analysis in different times such as ten minutes before induction (T1), aftersternotomy (T2), and at30min after CPB (T3), rewarding to34℃(T4),end ofsurgery(T5).Radial artery and internal jugular vein blood oxygen saturation were furthermeasured and the arterial blood oxygen contentment and O2ER were calculated. Duringand after operation, mean blood pressure, central venous pressure, heart rate, Bispectralindex, arrhythmia and postoperative complications were also observed. Result:30minutes after CPB, The arterial、venous lactate and blood glucose oftwo groups are increase；The BIS is decrease. But the trend of DexmedetomidinePretreated is lower than control group. It is statistically significantly (P＜0.05). As forHR, the trend of Dexmedetomidine Pretreated on the time of sternotomy is lower thancontrol group (P＜0.05). Other indicator(MAP、CVP、CaO2、CvO2、VO2、ERO2) arenot statistically significant.Conclusion:Dexmedetomidine Pretreated inhibit metabolism in CPB.It canreduce the metabolic disorders of stress response.