体外循环心脏手术α稳态、pH稳态下颈动、静脉血乳酸值的变化

目的探讨体外循环心脏直视手术(Cardiopulmonarybypasssurgery，CPBS)α稳态(α-stat)方式与pH稳态(pH-stat)方式对脑氧代谢的影响。方法62名CPBS患者随机分为α-stat组和pH-stat组，于CPBS的不同阶段观察颈动、静脉血乳酸值的变化。结果α-stat和pH-stat下脑血乳酸值明显增高，并于复温末期增至最大，说明脑组织乏氧代谢增强，机体存在氧债。α-stat组组内比较无统计学意义(P>0．05)，而pH-stat组复温过程中(鼻温升至35℃)颈静脉血乳酸值比动脉血乳酸值明显增高(P<0．05)，说明该组脑组织乏氧程度更严重；但两组间比较无统计学意义。结论不论是α-stat还是pH-stat均可使脑氧利用率降低，乏氧代谢增强，而pH稳态脑组织乏氧程度似乎更严重，但二者对脑氧代谢率(Cerebralmetabolictateforoxygen，CMRO2)的影响无何不同。

The lactate metabolism variation of jugular arteries and veins in α-stat and pH-stat during cardiopulmonarybypass surgery

Objectives To investigate the effect on cerebral metabolic rate for oxygen in α-stat and pH-stat during cardiopulmonarybypass surgery. Methods The lactic acid value were monitored in 62 patients during cardiopulmonary bypass surgery. Results The lacticacid values of jugular arteries and veins were notably higher in times of α-stat and pH-stat and highest in calefaction ( P < 0.01) whichshowed cerebral anoxia,but comparison of the lactate value between the two groups have no difference. Conclusions Both a-stat and pH-stat can decrease the cerebral usability of oxygen. Anonic metabolism is increased and seems more serious in pH-stat. But CMRO2 in α-stathas insignificance at statistics as compared with pH-stat.