The Realationship Between Different Hct And Brain Injury When ? Type Aortic Dissection Operates During Deep Hypothermic Circulatory Arrest

Objective To observe the effects of different Hct on brain injury in patients with type I aortic dissection during deep hypothermic circulatory arrest during cerebral perfusion.By observing the rate of cerebral oxygen metabolism during the circulatory arrest,the incidence of postoperative s-100 b ? NSE and postoperative cognitive dysfunction,the appropriate Hct for reducing brain injury was determined.Method Collecting 60 cases of type I aortic dissection which their Hct are not less than30%,before operation,these patients were average divided into three groups,.the Hct of the group H1 was maintained at about 20%;the Hct of the group H1 was maintained at about25%;the Hct of the group H1 was maintained at about 30%.After anesthesia(T0),after cardiopulmonary bypass 5min(T1)and circulatory arrest 5min(T2),after the recovery cycle(T3),5 min after cessation of cardiopulmonary bypass(T4),sewing leather(T5),5hours after operation(T6),24 hours after operation(T7)of these eight times when collect blood sample(5ml)which are used to detecte cerebral vein injury marker s-100b protein and neuron specific enolase by ELISA.At the same time,after stopped circulation circulatory arrest 5min,after circulatory arrest 20 min,after the completion of the distal aortic anastomosis when pump 2ml internal jugular vein blood gas in patients which calculate cerebral oxygen metabolism.One day before surgery awake after operation and before discharge of these three time when evaluate the Mini-mental State Examination(MMSE)scores.Results1.H1:Hct19.6%±0.7%,H2:Hct24.7%±0.6%,H3:Hct29.6%±0.8%.2.,There was no statistically significant difference in s-100 b protein between the three group(P>0.05).In T1,T2,and T7 point,three groups of s-100 b protein were significantly increased;comparison among groups;T6,T7,three group s-100 b protein level decreased,nearly normal level(P>0.05),but the s-100b protein level of H1 group was higher than that of H2,H3;however,H2 and H3 had no statistically significant difference(P>0.05).There was no significant difference in NSE level among the three groups(P>0.05)at the T0?T1?T2 three points.Comparison with T0,three groups of patients NSE were significantly increased in T1,T2,T3,T4,T5,T6,T7(P<0.05);at each time point between the three groups,group H1 increased significantly higher than H2 and H3,the differences were obviously significant(P<0.05).There was no significant difference between the two groups of H2 and H3 in s-100 b and NSE(P>0.05).There was no statistically different among the three groups at T0 points in the NSE levels(P>0.05).3.During deep hypothermic circulatory arrest in three groups,cerebral oxygen metabolism rate were reduced.The differences were not obviously significant(P>0.05);there was no significant difference in cerebral oxygen metabolism rate between circulatory arrest after circulatory arrest 20 min and the circulatory recovery(P>0.05).4.1 days before operation and MMSE scores of the three groups had no statistical significance(P>0.05).In the postoperative awake patients,the MMSE score between the three groups were decreased,H1 decreased significantly lower than H2,H3,the difference was obvious statistical significant(P<0.05).Before discharge,it has no obvious difference between the three groups in H1,H2 and H3.In the three group have no permanent neurological dysfunction,H1 group had transient neurological dysfunction such as manic delirium,exceeding H2,H3 groups,the difference was statistical significant.Conclusion The maintenance of high Hct25%-30% during deep hypothermic circulatory arrest and selective cerebral perfusion reduces the incidence of cognitive impairment and reduces brain damage in patients with type I aortic dissection...