Effects Of Different Narcotrend Index On Cerebral Oxygen Metabolism In Elderly Patients With General Anesthesia

Objective Elderly patients have poor tolerance to anesthesia and surgery for special Pathophysiological conditions and complex diseases,brain ischemia and Hypoxia are more easy occured during operation,Which may lead to a series of complication,such as postoperative cognitive dysfunction and so on.Cycle Influctuation could be caused by the changes of anesthesia depth,which lead to adverse effects on cerebral blood flow and cerebral oxygen metabolism. Propofol was infused by TCI target-controlled of total intravenous anesthesia for abdominal surgery in elderly patients.Three different anesthesia depth were preset, and cerebral oxygen metabolism were monitor at five time points,this study was investigate the effects of different Narcotrend index on cerebral oxygen metabolism in elderly patients with general anesthesia.Methods Ninety elderly patients undergoing selective abdominal surgery( less than two hours) were randomly divided into three groups,including group A(anesthesia depth maintained with the target of NTI at D0 level),group B(NTI at D2 level)and group C(NTI at E1 level). 10 min before Anesthesia induction(T0), 10 min after NTI at preset index(T1), 30 min after NTI at preset index(T2), skin closure Immediate(T3), at the end of the surgery(T4),MAP and HR were recorded and blood-gas analysis was performed after the blood was taken from radial artery and the internal carotid vein.Arterial blood oxygen saturation(Sa02),Jugular bulb venous oxygen saturatio(Sjv02),Arterial blood oxygen partial pressure(Pa02),Venous blood oxygen partial pressure(Pjv02),Arterial lactate value(a Lac),Venous oxygen content(jv Lac),Arterialoxygen content(Ca02),Venous oxygen content(Cjv02)were record,and difference of arterio-venous oxygen(Da-jv02),radial artery- internal jugular bulb lactic acid difference,(VADL),Cerebral oxygen etrction ratio(CER02) were calculate.Results there were no significant difference in age, operative time, weight, height, sex ratio during the three groups(P> 0.05), compared with the T0, Sjv O2 increased D,a-jv02,CER02 reduced in group B and C at each time point(P <0.05). Compared with group A, Sjv O2 increased, Da-jv02, CER02 reduced in group B and C at each time point(P<0.05). Compared with group B, Sjv O2 increased in group C at each time point(P<0.05). MAP at T1 to T4 in all three groups increased significantly There were no statistically significant difference in VADL at each time point among the three groups(P> 0.05).Conclusions The difference of anesthesia depth not only have an impact on hemodynamics,but also brain oxygen metabolism in elderly patients with general anesthesia.if the hemodynamic were stable, the oxygen supply- consumption balance will be maintain,when narcotrend index maintained at D0, D2 and E1.