Effects Of Temporary Arterial Occlusion On Levels Of Excitory Amino Acids In The Regional Brain In Aneurysm Surgeries: Studys With Microdialysis

Objective To explore the changes of the excitatory amino acids(EAAs, including Glu and Asp) in the extracellular fluid of the cerebral aneurysm microsurgery patients with microdialysis,and to know the changes of the brain biochemical metabolism before and after temporary occlusion, helping us using temporary arterial occlusion clips.Methods We selected 18 patients needing temporary arterial occlusion in intracranial aneurysm surgeries. The microdialysis probes were punctured into the cerebral cortices in the operation of clipping aneurysm to perfuse Ringer's solution and collect fluid for microdialysis once every 10 minutes before and after temporary occlusion with perfusion speed of 2μl/min. The collected fluid was tested by high performance liquid chromatography (HPLC) for examining the values of Glu and Asp.Results After temporary arterial occlusion, 0～10min Glu and Asp contents in the cerebral cortices had no evidence changes(P>0.05), 10～20min the contents increased strikingly(P<0.05)and after 20min the contents increased considerably(P<0.01).Conclusion With microdialysis we can monitor the changes of EAAs from the molecular level of cell metabolism in aneurysm microsurgeries. After temporary occlusion, EAAs increased. We should reduce the use and the time of the temporary occlusion as possible. The microdialysis is a kind of useful techniques to many aspects in neurosurgery experiment study and clinic use.