The Influencing Factors Analysis Of Regional Cerebral Oxygen Saturation During Cardiopulmonary Bypass

Objective: To understanding the main influence factors of Regional CerebralOxygen Saturation （rScO₂） were during Cardiopulmonary Bypass （CPB） to keep thenormal range of rScO₂.Methods: Sixty patients underwent elective cardiac surgery were enrolled in thestudy. The mean value of the cerebral oxygen saturation, Hematocrit（HCT）,hemoglobin （HB）, arterial blood oxygen partial pressure （PaO₂）, arterial blood CO₂partial pressure （PaCO₂）, blood lactic acid （Lac）, PH value, mean arterial pressure（MAP）,and nasopharynx temperature （T） were recorded in the7periods:Pre-operation（t1）,pre-inducement（t2）, from inducement to the beginning of CPB（t3）,from the beginning of CPB to the end of nose temperature cooling（t4）, from the endof nose temperature cooling to the beginning of warming（t5）, from the beginning ofwarming to the end of CPB（t6）, the30minutes after CPB during the operationperiod（7）. Seven value of rScO₂were analyzed by one-way ANOVA. The correlationof rScO₂with HCT,HB,PH,PaCO₂,PaO₂,MAP,Lac,T at the Corresponding time pointswere used multiple logistic regression analyses.Result: The rScO₂are no significant difference between t1and t2whichPre-operation rScO₂0.6±0.034and pre-inducement rScO₂0.65±0.037. There is nocorrelation between rScO₂and factors. Only temperature affected rScO₂in t3period,standard regression coefficient Beta=0.385. P=0.002;T and MAP affected the rScO₂in t4period,T standard regression coefficient Beta=0.226, MAP standard regressioncoefficient Beta=0.295, P=0.009,MAP is slightly stronger;PaCO₂and Lac affected therScO₂in t5period, PaCO₂standard regression coefficient Beta=0.268, Lac standardregression coefficient Beta=0.465, P=0.001, Lac is slightly stronger;PaCO₂and Lacaffected the rScO₂in t6period, PaCO₂standard regression coefficient Beta=0.274,Lac standard regression coefficient Beta=0.223, P=0.045, PaCO₂is slightly stronger;only temperature affected rScO₂in t7period, standard regression coefficient Beta=0.285, P=0.001. PH, PaO₂, HB, HCT have no effect on rScO₂frompre-operation to the30minutes after CPB during the operation, P>0.05.Conclusion: The main influence factors of rScO₂during CPB are PaCO₂,Lac,hypothermia and MAP. There were no correlation between HCT, HB, PH, PaO₂andrScO₂.