ABSTRACT
Objective:To determine whether mild hypothermia,isoflurane and propofol reduce gultamate release in rat hippocampus brain slices after hypoxia. Method: Brain slices preparations were separated and incubated from rat hippocampus. Glutamate released from rat brain slices during chemical anoxia(100?M KCN)were measured with a fluorescence assay,at 28℃,31℃ and 37℃ after anoxia and after administration of 1 MAC of isoflurane and 200 ?m propofol respectively. Result: Glutamate release was significantly reduced at 28℃ or 31℃ compare with that at 37℃ (P
ABSTRACT
Ten mongrel dogs,divided randomly into a control group (A) and a cerebroplegia group (B) ,were supported by closed-chest cardiopulmonary bypass,subjected to 2 hours of hypothermic circulatory arrest at 18 C. In group B, oxygenated asanguineous solution 50ml/kg was infused into the carotid artery at the onset of arrest. and 10 ml/kg was supplemented every 30 minutes during 2hours arrest. Nothing was infused in group A. Then all animals were rewarmed to 37 C and killed 6 hours later At five time points cerebral cortex was collected to study adnosine triphosphate (ATP),malondialde hyde (MDA) and ultrastructure. Electroencephalography (EEG) was recorded continuously. In group A, ATP content decreased gradually from the beginning of arrest to the end of the experiment (P
ABSTRACT
A certain amount of potassium chloride is required to correct the hypokalemia occuring commonly during perioperation,but the overdosage may be harmful. To investigate the proper dose of KCl,40 adult rabbits were randomly and evenly assigned to be intravenously infused with normal saline(group Ⅰ),or saline containing 4,25 or 50 mmol/L KCI (group Ⅱ,Ⅲ,Ⅳ),at rate of 10 ml?kg~(-1)?h~(-1) during operation respectively. As compared with those before operation,the serum level of potassium decreased significantly in group Ⅰ and Ⅱ, changed unsignificantly in group Ⅲ,and increased in group Ⅳ during and after operation;the potassium amounts in liver and skeletal muscles increased markedly after operation. S-T segment was depressed in group Ⅰ and Ⅱ,T wave became peaked in group Ⅳ, and ECG remained normal in group Ⅲ. it is indicated that intravenous KCl infusion at concentration 25 mmol/L and rate of 10ml?kg~(-1)?h~(-1) may properly correct the hypokalemia during perioperation,and the occurance of perioperatine hypokelemia may be related to the uptake of liver and skeletal muscles