亚低温治疗对重型颅脑损伤脑脊液乳酸及酸碱平衡的影响

Effects of mild hypothermia on lactate levels and acid-base balance in cerebrospinal fluid after severe head injury

目的 对重型颅脑损伤患者在亚低温治疗过程中的脑脊液PO2 、PCO2 、pH值、乳酸水平及动脉血pH值进行监测分析 ,探讨亚低温治疗对重型颅脑损伤脑脊液酸碱平衡的影响。方法 收集 4 2例重型颅脑伤 (GCS≤ 8分 )患者 ,平均年龄 4 1 .7岁。亚低温组于伤后 1 2小时内实施亚低温治疗 (32～ 34℃ ) ,时程 3～ 5天 ;对照组给予常规治疗。两组均于降温前、降温 2 4、4 8、72小时各时段测定脑脊液PO2 、PCO2 、pH值、乳酸水平及动脉血pH值 ,并进行统计学分析。结果 脑温及体温的变化对血pH值影响不大。血pH值大致波动在正常范围 ,而脑脊液pH值始终低于正常。各时段的脑脊液pH值均明显低于血pH值 (P <0 .0 5 )。亚低温组和对照组在降温前时段 ,脑脊液PO2 、PCO2 、乳酸水平无显著性差异 (P >0 .0 5 ) ;降温 2 4、4 8、72小时时段 ,亚低温组脑脊液PO2 、PCO2 、乳酸水平明显低于对照组。结论 亚低温治疗在降低重型颅脑损伤 (GCS≤ 8分 )患者脑脊液PO2 的同时 ,也降低了脑脊液PCO2 、乳酸水平 。

Objective To investigate the effects of mild hypothermia on brain acid base balance after severe head injury through monitoring the changes of CSF PO 2 ,PCO 2 ,pH and lactate level and arterial pH in patients with severe head injury treated with mild hypothermia.Methods Forty two patients (average age 41.7 years old) with severe head injury (GCS≤8) were selected for this study. Mild hypothermia group received cooling (32～34℃) for 3 5 days within 12 hours after head injury. Control group received ordinary treatment. CSF PO 2 ,PCO 2 ,pH and lactate level and arterial pH were examined before cooling and 24h,48h,72h after cooling.Results There was no obvious effect in arterial pH following the changes of brain and body temperature. Arterial pH changed within normal range but CSF pH was in acidosis condition from beginning to end. There was no difference in CSF PO 2 ,PCO 2 ,lactate level in two groups before cooling (P>0.05). CSF PO 2 ,PCO 2 ,lactate level was lower in cooling group than that in control group 24h,48h,72h after cooling.ConclusionMild hypothermia may decrease CSF PO 2 ,PCO 2 ,lactate level in severe head injury but can not ameliorate the low CSF pH.