ABSTRACT
In recent years,a large number of pre-clinical cell and animal studies have shown that isoflurane as the representative of a variety of clinical commonly used inhaled anesthetics may induce neurotoxicity,including neuroapoptosis,neurodegeneration,and long-term neurocognitive and behav? ioral deficits. Mitochondrial dysfunction and oxidative stress play an important role in the side effect. This paper reviews the currently relatively clear mechanisms by which isoflurane causes postoperative cognitive dysfunction and prevention methods. Specific mechanisms of these effects include inhibition of the hydrolysis of brain-derived neurotrophic factor precursor in hippocampal neurons,promotion of neuronal apoptosis, overactivation of 1,4,5-inositol trisphosphate receptor, intracellular calcium imbalance,acetylcholine inhibition,inhibition of long-term potentiation. At the same time,current preventive studies are introduced,such as dexmedetomidine and xenon.
ABSTRACT
Objective To investigate the effect of isoflurane inhalation during gestation period on plasticity of hippo-campal synapses in offspring rats. Methods Ten healthy pregnant SD rats at 14 day gestation were randomly divided into 2 gorups ( n = 5 each): control group (group C) and isoflurane group (group I). The rats in group C were mechanically ventilated with O2 while in group I the rats inhaled 1.3% isoflurane in O2 for 2 h a day until labor. Four weeks after birth 4 offspring rats from each pregnant rats (2 male, 2 female) were tested for learning and memory abilities using Morris water maze. Then the offspring rats were sacrificed and hippocampi isolated. The synaptic structure of hippocampal CA1 area was examined by trans-electron microscopy. Results Morris water maze test showed that the escape latency was significantly shorter and the number of times of spanning flat roof greater in group C than in group I. The structure of hippocampus was intact in group C but incomplete in group I. Meanwhile the thickness of synaptic density was significantly decreased in group I. Conclusion Isoflurane anesthesia of pregnant rats may induce learning and memory disabilities in offspring rats by inhibiting the plasticity of synaptic structure in hippocampus.
ABSTRACT
Objective To investigate the changes in serum hyaluronic acid level at different periods of experimental piggyback liver transplantation and its significance. Methods Fifteen pairs of healthy pigs of both sexes weighing (28.3 + 5.0)kg undergoing liver transplantation were studied. The donor pigs were slightly smaller than the recipient pigs. The recipient pigs were premedicated with intramuscular ketamine 8mg kg-1 and atropine 0.02mg-kg-1 .Anesthesia was induced with propofol 2mg-kg-1 , fentanyl 0.002mg-kg-1 and vecuronium 0.1mg-kg-1 iv. After tracheal intubation the animals were mechanically ventilated. CVP line was placed via internal jugular vein. Carotid artery was cannulated for continuous BP monitoring. Anesthesia was maintained with iv propofol, fentanyl and vecuronium. Circulatory stability was maintained by infusion of crystalloid, colloid, plasma and whole blood of pig. Blood samples were taken from peripheral vein before operation (T0), pre-anhepatic phase (T1), anhepatic phase (T2) and neohepatic phase (T3) for determination of serum hyaluronic acid concentration by radioimmunoassay. At the same time liver function tests, ALT, AST, y-GT were also examined. Results The average time of liver transplantation was (343+74) min. SBP decreased by (23.51+5.87 ) mm Hg and DBF by (11.35+7.81) mm Hg after induction of anesthesia. Serurn hyaluronic acid level was 267ug-L-1 before operation (T0) and rose to 1743ug-L-1 at T1 , and 9530ug-L-1 at T2 (P