ABSTRACT
Aiming at building research disciplines,Xijing hospital has initially achieved a strategic transformation into a hospital with research disciplines,with such measures as scientific layout of disciplines,making of advantageous disciplines with overseas benchmarks,encouragement of potential disciplines with advantageous disciplines,promotion of medical innovation with innovative ideas,and upgrading clinical service quality with technical innovation.
ABSTRACT
BACKGROUND:Repeated hyperbaric oxygenation (HBO) preconditioning induces tolerance against ischemia in spinal cord. The confirmation of this phenomenon paves a new way in clinic to prevent and treat complications of spinal ischemia following thoracoepigastric aorta surgery. Probing into its mechanism of is chemic tolerance has provided basis for clinical application.OBJECTIVE: To investigate the changes of mitochondrial structure and ATPase activity during spinal cord ischemic tolerance induced by repeated HBO preconditioning in rabbits.DESIGN: Randomized and controlled trial.SETTING: Department of Anesthesiology, Xijing Hospital of Fourth Military Medical University of Chinese PLA.MATERIALS: The experiment was conducted in the hyperbaric oxygen chamber of the Department of Air Medicine; Experimental Animal Center of the Department of Anesthesiology, Xijing Hospital of Fourth Military Medical University of Chinese PLA, between March and June 2004. Totally 50 male New Zealand rabbits were selected.METHODS: Fifty male New Zealand rabbits were randomly divided into two groups: simple ischemia control group and HBO group with 25 rabbits in each group: 0.25 Mpa, 100% O2, one hour per day for 5 days. Spinal ischemia model was prepared 24 hours after the last preconditioning.Spinal cord ischemia (20 minutes)/reperfusion model was prepared by blocking the infrsrenal aorta. The motor function of hind-limbs was scored at 6 hours, 24 hours and 48 hours after reperfusion. The mitochondrial ATPase activity was measured and compared between two groups before ischemia, at 6 hours, 24 hours and 48 hours after reperfusion.MAIN OUTCOME MEASURES: ① The score of motor nerve function of the hind-limbs; ② The activity of mitochondrial ATPase; ③ Pathological evaluation.RESULTS: Totally 50 rabbits were involved for result analysis, and finally 25 rats in each group entered statistical analysis with no loss in the midway. ① The score of motor nerve function of the hind-limbs in HBO group at 6 hours, 24 hours and 48 hours after HBO preconditioning was significantly higher than that in control group (P ＜ 0.01). ② The activity of mitochondrial ATPase: the mitochondrial Na+, K+-ATPase activity and Ca2+, Mg2+-ATPase activity at each time point of the animals in the two groups after is chemia were significantly decreased; Na+, K+-ATPase activity in HBO preconditioning group at 6 hours, 24 hours and 48 hours of ischemia was significantly higher than that in control group (P ＜ 0.01); Ca2+, Mg2+-ATPase activity at 6 hours and 24 hours after ischemia was significantly higher than that in control group (P ＜ 0.01). ③ Pathological evaluation: The structure of mitochondria in control group was seriously damaged while it was found almost normal in spinal cord in HBO group animals at 48 hours after reperfusion.CONCLUSION: The mechanism of ischemic tolerance induced by hyperbaric oxygenation pretreatment may partly be related to the attenuation of mitochondria ATPase activity decrease after ischemia, thereby protecting the function of mitochondria.
ABSTRACT
OBJECTIVE:To evaluate the clinical effects of urapidil on cardiovascular response induced by sympathetic stimulation during front approach cervical vertebra operation.METHODS:One hundred and twenty patients undergoing front approach cervical vertebra operation were randomly divided into three groups.Patients in URA group treated with0.5mg/kg urapidil and patients in NIC group treated with5?g/kg nicardipine when systolic blood pressure(SBP)and heart rate(HR)increased by sympathetic nerve stimulation during the operation.And patients in COM group only increased their anesthesia degree with isoflurane at the same situation.The patients’SBP and HR were observed and compared among three groups at the time before the sympathetic nerve stimulation,and5minutes and10minutes after the drugs treatment respective?ly.RESULTS:The patients’SBP and HR in URA group had no significantly increase after administration of urapidil.In NIC group,although the patients’SBP had no significantly increase,the patients’HR increased significantly after nicardipine was used.But the patients’SBP and HR increased significantly after improved anesthesia degree with isoflurane.CONCLUSION:Urapidil has better effect on sympathetic cardiovascular response during the front approach cervical vertebra operation com?pared with nicardipine.