ve To investigate the time course of potentiation of rocuronium produced by 1MAC of desflurane or isoflurane. Methods Twenty-four ASA I-II patients aged 18-60 years undergoing elective abdominal operation under general anesthesia were studied. Patients with neuromuscular, liver or kidney disease and those receiving any drug which may affect neuromuscular transmission were excluded. Premedication consisted of intramuscular phenobarbital 0.1 and atropine 0.5mg 30min before operation. Anesthesia was induced with midazolam 0.1-0.2 mg?kg-1, fentanyl 6?g.kg-1 and etomidate 0.3mg?kg-1 .Tracheal intubation was facilitated with rocuronium 0.6mg?kg-1 iv. The degree of neuromuscular block was monitored by measuring muscle response to TOF using accelerography (Biometer) . For maintenance of anesthesia the patients were randomly assigned to receive either propofol + fentanyl (control group) or 1 MAC of desflurane + propofol + fentanyl (desflurane group) or 1 MAC of isoflurane + propofol + fentanyl(isoflurane group). Rocuronium was continuously infused during operation to maintain T1 at 5 % of the control and the infusion rate was recorded every 15 min. Results There were no significant differences among the three groups with respect to sex, age, body weight and duration of anesthesia. In Des and Iso groups the infusion rate of rocuronium was reduced in an exponential manner and maximal potentiation occurred at 90 min of isoflurane or desflurane inhalation. The maximal reduction in infusion rate was 42.7 % in Des group and 37.6% in Iso group. There was no significant difference between the two groups.Conclusions Desflurane and isoflurane can potentiate the muscle relaxation produced by rocuronium in a similar degree and the potentiation is time dependent.

Objective To investigate the change in neuromuscular blocking effect of rocuronium induced by liver dysfunction. Methods Forty patients undergoing elective liver and biliary tract operation under general anesthesia were divided into 2 groups : (A) control group included 20 patients with normal liver function and (B) liver dysfunction group included 20 patients with obstructive jaundice. The premedication consisted of phenobarbital 0.lg and atropine 0.5 mg. Anesthesia was induced with midazolam 0.1 mg?kg-1,fentanyl 6?g?kg-1 and etomidate 0.3 mg?kg-1.The neuromuscular function was monitored by TOF stimulation of the ulnar nerve using accelerograph (Biometer).Rocuronium 0.6 mg?kg-1 was administered iv via the vein in the upper arm.The patients were intubated when T1 was 95% depressed and mechanically ventilated.PETCO2 was maintained at 35-40 mm Hg.The onset time (from the end of injection to T1=0),clinical duration of action (from the end of injection to 25% recovery of T1) and recovery index (T1 from 25% to 95% ) were recorded.MAP, HR and SpO2 were recorded before and at 5 and 10 min after rocuronium injection.Results The demographic data including sex, age and weight were comparable between the two groups. The onset time was (63?19) s in group A and (70?21) s in group B.The difference was not statistically significant. The clinical duration of action was (41?16) min in group A and (67?29) min in group B (P0.05).Conclusion Liver dysfunction induced by obstructive jaundice prolongs the clinical duration of action,but does not significantly affect the onset time of and recovery from rocuronium.

Objective To explore the relationship between Bispectral index （BIS） values,Narcotrend index （NTI） values and the predicted effect-site concentration （EC）during target-controlled infusion of propofol. Methods In 30 patients during target-controlled infusion of propofol,the propofol infusion was set at an initial EC of 0.5 mg/L and increased by 0.5 mg/L steps every 5 min until 5 min after the modified observer＇s assessment of alertness/sedation scale（OAA/S） values reached zero. The predicted EC of propofol,the values of NTI,NTS and BIS were recorded,and the sedation level were examined by the modified OAA/S every 20 s. The predicted EC of propofol and the values of BIS and NTI at LVC and LOC in 5%,50% and 95% of patients were calculated. Results There were good linear correlations between BIS,NTI and the predicted EC of propofol （r2=0.787,0.792）.The predicted EC of propofol at LVC in 5%,50% and 95% of patients were 1.2,1.8 and 2.5 mg/L,respectively. The values of BIS and NTI at LVC in 5%,50% and 95% of patients were 78.2,68.2 and 58.2; 73.9,64.9 and 55.8,respectively.The predicted EC of propofol at LOC in 5%,50% and 95% of patients were 1.6,2.6 and 3.5 mg/L,The values of BIS and NTI at LOC in 5%,50% and 95% of patients were 74.6,58.2 and 41.5,66.2,55.8 and 45.3,respectively. Conclusion During target-controlled infusion of propofol,LVC and LOC occurred within a definite range of predicted effect-site concentrations.There were the good linear correlations between BIS,NTI and the predicted EC of propofol.NTI may be more useful than BIS in predicting LVC and LOC because of the smaller range of values for the two clinical end-points.

Objective To observe the effects of sulfentanil with various doses on the Bispectral index and Narcotrend index without nociceptive stimulus under the sevoflurane anesthesia.Methods Forty-eight ASA Ⅰ or Ⅱ patients undergoing gynecological operations were randomly divided into four groups（n=12）.All patients were induced with sevoflurane,the end-tidal concentrations of sevoflurane in all groups were adjusted to 1.0 MAC after tracheal intubation. Fifteen minutes later,sufentanil was injected in groups of B,C,D with the doses of 0.25,0.5,1.0 μg/kg respectively. The observations were finished when the values of Bispectral index and the Narcotrend index reached the minimum over 5 min. The values of Bispectral index and the Narcotrend index were recorded every minutes after the sufentanil injection. Results Among all groups,the BIS,Narcotrend values and tmax produced no statistical difference. Compared with the time when conscious lost,BIS and Narcotrend values were significantly lower when sevoflurane anesthesia reached steady state in all groups. The values of BIS and Narcotrend were significant lower after the injection of sufentanil in the groups of B,C and D（P0.05）. Conclusion Under the sevoflurane anesthesia with the steady end-tidal concentration of 1.0MAC,sufentanil could reduce the values of BIS and Narcotrend index without nociceptive stimulus without distinction among different doses.

Pain has been defined as an unpleasant sensory and emotional experience that is associated with actual or potential tissue damage,or is described in terms of such damage.Pain individual difference increases the complexity of clinical diagnosis and treatment of pain.China started relatively late on pain research and standardized pain treatment.It is necessary for further research on pain related to the clinical problem,the development of pain translational medicine,and improvement of clinical quality.The paper carries on the review.

Objective To evaluate the role of oxidative stress in the spinal neurotoxicity induced by ropivacaine in rats.Methods Ninety pathogen-free male Sprague-Dawley rats,weighing 250-320 g,aged 3 months,in which intrathecal catheter was successfully implanted into L5,6 interspace without complications,were randomly divided into 3 groups (n =30 each) using a random number table:control group (group C),ropivacaine group (group R),and antioxidant Tempol group (group T).The rats received 1％ ropivacaine 1.2 μg/g for 8 times at 1.5 h intervals through the catheter in R and T groups,while the rats received the equal volume of normal saline instead in group C.In T group,Tempol 20 μg/g was injected intrathecally at 4,8,12,24,48 and 72 h after the last injection of ropivacaine.The rats were sacrificed at 1,3,5,7 and 14 days after the end of ropivacaine injection,and their lumbar enlargements were removed for TUNEL staining to detect the cell apoptosis.SOD activity was determined by colorimetry and MDA content was measured using TBA photoelectric colorimetry.Apoptosis index was calculated.Results Compared with group C,apoptosis index and MDA content were significantly increased,and SOD activity was decreased in R and T groups.Compared with group R,apoptosis index and MDA content were significantly decreased,and SOD activity was increased in group T.Conclusion Oxidative stress is involved in the development of spinal neurotoxicity induced by ropivacaine in rats.

Objective To evaluate the ischemic postconditioning on endoplasmic reticulum stress during cerebral ischemia/reperfusion (I/R) in rats.Methods Ninety adult male Sprague-Dawley rats,aged 350-450 g,were randomly divided into 3 groups (n =30 each) using a random number table:sham operation group (S group),I/R group,and ischemic postconditioning group (group P).Focal cerebral I/R was induced by electrocoagulation of left middle cerebral artery and 30 min occlusion of bilateral common carotid arteries followed by reperfusion.In group P,bilateral common carotid arteries were subjected to 3 cycles of 30 s reperfusion and 10 s ischemia at the beginning of reperfusion.At 24 h of reperfusion,neurological deficit was scored,and cerebral infarct size was detected by TTC staining.At 6,12 and 24 h of reperfusion,the expression of glucose-regulated protein 78 (GRP78),C/EBP homologous protein (CHOP) and caspase-12 in the ischemic area were measured (using immunohistochemistry).The neuronal apoptosis in the ischemic area was detected by TUNEL.Results Compared with S group,the neurological deficit score was significantly increased,cerebral infarct size was enlarged,the neuronal apoptosis was increased,and the expression of GRP78,CHOP and caspase-12 was up-regulated in I/R and P groups.The neurological deficit score was significantly lower,cerebral infarct size was smaller,the expression of GRP78 was higher at 12 and 24 h of reperfusion,the neuronal apoptosis was lower at 24 h of reperfusion,and the expression of CHOP and caspase-12 was lower in group P than in group I/R.Concluion Ischemic postconditioning can inhibit neuronal apoptosis mediated by endoplasmic reticulum stress during cerebral I/R,which dose not play a leading role in cerebral protection in rats.

Objective: To evaluate the efficacy of the bispectral index (BI) in predicting patient movement on skin incision under sevoflurane anesthesia with the PK statistic. Method: Twenty-nine adult patients. scheduled for elective upper abdominal surgery, were selected. Anesthesia was induced with propofol and 4%-5% sevoflurane in oxygen and maintained with one of four randomized sevoflurane concentrations (0.6MAC, 1.0MAC. 1.5MAC and 2.0MAC) for fifteen minutes, then skin incision was performed by the surgeon at the planned site of the surgery, and each patient was observed carefully about 2 minutes to detect purposeful movement. The data of BI, 95% SEF, MAP, SABP and HR in one minute before skin incision were applied to statistically analysis. Result: The P_K was significantly greater than 0.5 for the sevoflurane level and the BI. The PK of 95% SEF. SABP and MAP were less than that of the level of sevoflu or Bl. but was significantly greater than 0.5 The P_K of HR was close to 0.5. Conclusion: These indicators of B, BP and 95% SEF may predict patient movement to skin incision under sevoflurane anesthesia. of which the BI is the most sensi tive.

Objective To investigate the relation between the expression of Bcl-2 protein and protection against ischemic neuronal damage by preconditioning with sublethal ischemia .Methods The cerebral ischemia was induced by occlusion of bilateral common carotid arteries .Sixty-three gerbils were divided randomly into four groups:sham operative control group (group A,n=5),ischemic preconditioning control group (group B ;n=6) with a single 2-min cerebral ischemia; ischemia preconditioning group (group PC,n=26) and ischemic control group (group IR,n=26) with 5-min ischemia being induced following 3 days of reperfusion with or without 2-min ischemic preconditioning,then with reperfusion lasting 4 hours (group PC1,n=5;group IR1,n=5),24 hours (group PC2,n=7;group IR2,n=7),72 hours (group PC3,n=7;group IR3,n=7)or 7 days (group PC4,n=7;group IR4 ,n=7) respectively.Paraffin sections of hippocampus were used for Bcl-2 protein immunohistochemical staining.Results In group B,Bcl-2 protein immunoreactivity (the intensity of staining) significantly increased as compared with that in group A(P

Objective To study the effects of selective mild cerebral hypothermia on endogenous anti-injury mechanism in brain tissue after cardiac arrest and resuscitation. Methods Fifteen healthy mongrel dogs of both sexes were anesthetized and intubated. Cardiac arrest was induced by potassium cardioplegia and cross-clamping of aorta, vena cava superior and inferior and azygos vein and maintained for 18min. The animals were randomly divided into 3 groups: group A, in which no cardiac arrest was induced, served as control ( n = 4) ; in group B animals received routine cerebral resuscitation ( n = 5) ; in group C animals received selective mild cerebral hypothermia (34℃?0.5℃) and routine cerebral resuscitation ( n = 6) . After successful resuscitation, the animals were observed for 8 hours. At the end of the experiment the parietal cerebral cortex was removed for determination of MDA, GSH, LA, FFA content and activities of SOD(T-SOD, Mn-SOD, Cu-ZnSOD) and GSH-Px. Results FFA and LA content of brain tissue in group B was significantly higher than those in group A (P