Objective: To observe changes of EEG parameters,including bispectral index (BIS),spectral edge frequency(SEF)and median frequency(MF),and the association between the changes of EEG variables and hemodynamic responses to intubation during induction by propofol with or without fentanyl. Method: Twenty-four ASA grade Ⅰ-Ⅱ patients were randomly assigned to double-blindly receiving intravenous propofol/normal saline (group P, n=12)or propofol/fentanyl 2?g/kg(group PF,n=12), respectively. Intubation was performed following 5-min maintenance of BIS within 45?5. EEG and hemodynamic variables were recorded at endpoints of pre-induction, pre-intubation and post-intubation. Result:In group P,blood pressure and heart rate at post-intubation were significantly increased compared with pre-induction value(P

Objective To compare the influences of sulfentanyl or fentanyl combined with midazolam on respiratory function in slow induction of anesthesia.Methods Forty ASA Ⅰ-Ⅱ patients were divided into two groups.Anesthesia was induced with midazolam 0.03mg/kg in both groups,and fentanyl 2?g/kg(i.v.)was given in fentanyl group or sulfentanyl 0.2?g/kg(i.v.)in sulfentanyl group.Five minutes later,2ml of 1% decicaine was administered by cricothyroid membrane puncture to facilitate the intubation.Respiratory indexes(respiratory frequency,VT,MVV,PETCO2,SPO2),circulatory indexes(MAP,HR)and sedation level were measured before and 1,2,3,4,5 minute(s)after injection of drugs,at cricothyroid membrane puncture,and pre-and post-intubation.Results Patients showed respiratory depression(respiratory frequency was reduced)in both groups 2 minutes after injection of drugs.However,respiratory frequency was decreased more markedly in fentanyl group than that in sulfentanyl group.Ten out of 20 patients were obliged to receive breathing intervention in fentanyl group,but two in sulfentanyl group.Conclusion In combination with midazolam,sedative effect of sulfentanyl is stronger than that of fentanyl in equivalent analgesic dose,but with less respiratory depression.Sulfentanyl may be more suitable for slow induction of anesthesia.

Objective To study the effects of acute hypervolemi c hemodilution (AHH) on the coagulation and cardiac function in elderly surgical p atients. Method Sixty surgical patients, aged 60 to70, ASA Ⅰ~ Ⅱ, were randomly divided into three groups (n=20 for each group). 6% HES 50 0~1000ml was infused in a rate of 20ml/min during vasodilation with isoflurane i nhalation (group 1), nitroglycerin (group 2), or nicardipine (group3) with the a id of an intravenous injection pump. The blood coagulation and cardiac functions were observed during hemodilution. Results No significant diff erence was found among the three groups on cardiac function and coagulation func tion during 500ml 6% HES infusion. When the volume of infusion was over 1000ml, the parameters of cardiac function increased and those of coagulation decrease d significantly (P

Thirty patients, randomly assigned into three groups, received bolus injection of ketamine 0. 5mg/ kg,midazolam 40ug/kg and one of the three narcotics: fentanyl 3ug/kg (group F ) or sufentanil 0. 4ug/kg (group S)or dihydroetorphine 0. 3ug/kg(group D)just before incision, and then a constant infusion of ketamine 0. 8mg/kg, midazolam 40ug/kg and fentanyl 3ug/kg (or sufentanil 0. 4ug/kg, or dihydroetorphine 0. 3ug/kg)mixture in 100ml normal saline at a rate of 3ml/min for 30 min in beginning, and 1 - 1. 5ml/min thereafter for maintenance. The infusion of narcotics and midazolam was terminated about 45min, and he tamine 15min prior to the end of surgery. Blood pressure and heart rate were all stable,with recovery time shortest in group S (6. 5min ) and longest in group D (12. 5min). Anesthesia were satisfactory in all the patients,except one in group D. It is concluded that this combination of tv anesthetics may be simple and effective and can be considered as an alternative anesthesia technique in the management of mass casualties.

Objective To investigate the analgesic effect and safety of intravenous flurbiprofen axetil combind with fentanyl and propofol on coloscopy.Methods Ninety patients undergone coloscopy were randomly assigned into three groups according to different analgesics received(30 in each,groupⅠ: fentanyl 1?g/kg;groupⅡ flurbiprofen axetil combined with fentany 0.5?g/kg;group Ⅲ: fentany 0.5?g/kg).Patients in group Ⅱ received intravenous flurbiprofen axetil 1mg/kg 10min before examination.All patients were given intravenous midazolam 0.02mg/kg 2mins before examination,however patients in group Ⅰ received intravenous fentanyl 1?g/kg followed by intravenous propofol 0.5-1mg/kg,whereas patients in group Ⅱ and Ⅲ received intravenous fentanyl 0.5?g/kg followed by equal dosage of propofol.Propofol was administrated according to patients' reaction during examination.After the examination all patients were transferred to recovery room.BP,HR and SpO2 were measured before and after drug administration,when the coloscope reached the splenic flexure of the colon and after the examination.Dosage of propofol and fentanyl,duration of coloscopy,side effects and patients' memory of pain during examination were recorded.Results Propofol dosages of the three groups were 82.0?23.8mg,73.0?25.0mg and 108.2?36.5mg,respectively.Propofol dosage of group Ⅲ was much larger than that of groups Ⅰand Ⅱ(P0.05).Dizziness and nausea occurred in 17 patients in group Ⅰ when they left the recovery room,whereas the same side effects only appeared in one patient in group Ⅱ and 3 patients in group Ⅲ,respectively.It was shown by follow-up that all patients of the three groups had no memory of pain.Conclusion Intravenous flurbiprofen axetil may strengthen intraoperative analgesia during coloscopy,reduce the dosage of fentanyl and propofol,and decrease the side effects of anesthesia.

Objective To study the effects of total intravenous anesthesia and combined inhalation and intravenous anesthesia on arousing time and recovery quality in rectifying surgery of scoliosis. Methods Forty patients (ASAⅠ-Ⅱ) were divided randomly into total-intravenous anesthesia group and combined inhalation and intravenous anesthesia group (n=20 each). Target controlled infusion (TCI) with propofol (2-4?g/ml) was used for maintenance in total intravenous anesthesia group, while isoflurane (0.8%-1.5%) and nitrous oxide (50%) were used in combined inhalation and intravenous anesthesia group. TCI remifentanyl (2-6ng/ml) was used for maintenance in both groups. Results Arousing time were 19.7?5.1min in total intravenous anesthesia group, but 11.9?3.3 min in combined inhalation and intravenous anesthesia group (P

Objective To investigate the effects of different doses of propofol on cognitive function after chronic cerebral ischemia-induced injury in aged rats. Methods Eighty male SD rats, aged 18 months, weighing 400-500 g, were randomly divided into 4 groups ( n = 20 each): shame operation group (group S), chronic cerebral ischemia group (group I), two propofol groups (groups P1 and P2 ). The chronic cerebral ischemia was induced by permanent occlusion of bilateral common carotid arteries. On 1 day after operation, intraperitoneal normal saline 2.5 ml was injected twice a day for7 consecutive days in groups S and I, and intraperitoneal propofol 10 and 50 mg/kg in 2.5 ml of normal saline were injected twice a day for 7 consecutive days in groups P1 and P2 respectively. On 3rd and 33rd days after the last injection (T1.2), 10 rats in each group underwent Morris water maze test to assess the cognitive function. After the test was completed, the rats were sacrificed and the hippocampi were removed and sliced (450-500 μm thick). Schaffer lateral branch in CA1 region was stimulated to induce long-term potentiation (LTP). Results Compared with group S, the escape latency was significantly prolonged, the number of animals' swimming across the platform, the ratio of the swimming time spent in the forth quadrant to the total swimming time, and the success rate of LTP induction were significantly decreased at T1 and T2 in groups I, P1 and P2 (P ＜ 0.05). Compared with group I, the escape latency was significantly prolonged, the number of animals' swimming across the platform, the ratio of the swimming time spent in the forth quadrant to the total swimming time, and the success rate of LTP induction were significantly decreased at T1 in groups P1 and P2, and at T2 in group P2 ( P ＜ 0.05). Conclusion Propofol aggravates the damage to cognitive function while it attenuates the chronic cerebral ischemia-induced injury in aged rats, especially the high dose.

Objective:To examine the effects of acute or chronic administration of 7-nitro indazole (7-NI) on the MAC of sevoflurane and cerebellar cGMP levels in mice. Method:In acute experiment,sevoflurane MAC was determined in mice after 7-NI 120mg/kg, 180mg/kg or 120mg/kg plus L-arginine 600mg/kg was given intraperitoneally. During chronic experiment, MAC was measured on 1st, 4th and 7th day during week-long gavage feeding of 7-NI. The levels of cerebellar cGMP also were measured after acute and chronic administration of 7-NI. Result:Acute administration of 7-NI 120mg/kg decreased sevoflurane MAC by about 20% and cerebellar cGMP level by 96%. 7-NI 180mg/kg did decrease MAC not more than 7-NI 120mg/kg. No significant reduction of MAC was observed in mice treated by intraperitoneal 7-NI 120mg/kg+L-arginine 600mg/kg. In chronic experiment,sevoflurane MAC and cerebellar cGMP were decreased significantly on 1st 4th and 7th day to the similar extend, with 15%-20% reduction in MAC and 46%-60% in cGMP levels. Conclusion:Acute and chronic selective inhibition of nNOS decreases sevoflurane MAC and cerebellar cGMP levels in mice. The maximal reduction (only about 20%) of MAC can be obtained when cGMP levesl are decreased about 50% and further inhibition of generation of cGMP does not produce more enhancement to the potency of sevoflurane anesthesia. No compensatory mechanism for the inhibition of L-Arg-NO-cGMP pathway appears during week-long treatment with 7-NI.

Objective To investigate the effects of NO synthesis inhibition on pain threshold and binding capacity of NMDA receptor of hippocampus in rats. Methods Sixty-six SD rats of both sexes weighing (210 ? 20)g were randomly divided into 11 groups of six. Group I was used for determination of baseline values of pain threshold and binding capacity of NMDA receptor. In the five L-NAME groups (group Ⅱ-Ⅵ) 1% L-NAME in normal saline 50mg?kg-1 was given intraperitoneally (IP) . In the acute experiment pain threshold was determined 15 min (group Ⅱ ) and 30 min (group Ⅲ) after L-NAME IP injection. In the chronic experiment L-NAME 50mg?kg-1 was given IP twice a day for 1 day (group Ⅳ), 4 d (group Ⅴ) and 7 d (group Ⅵ) and pain threshold was measured 12h after last L-NAME administration. Group Ⅶ-Ⅺ served as control groups in which normal saline was given IP instead of L-NAME. Pain threshold was measured by response latencies following CO2 laser stimulation which was delivered to the medial surface of the ear. After determination of pain threshold the animals were decapitated and hippocampus was removed. The binding capacity of NMDA receptor with [3H] MK-801 was determined. Bmax and KD were determined by Scatchard analysis. Results There was no significant difference in pain threshold and binding capacity of NMDA receptor between group Ⅱ ,Ⅲ (acute experiment) and their control groups ( Ⅻ,Ⅷ). In chronic experiment pain threshold significantly increased after 1 and 4 d of L-NAME administration (group Ⅳ and Ⅴ) but return to the baseline value on the 7th day. NMDA receptor binding capacity increased in all three groups of chronic experiment. Bmax was significantly higher than the baseline value on the 4th and 7th day (group Ⅴ and Ⅵ). KD was significantly higher than the baseline value on the 4th day (group Ⅴ) but returned to the baseline on the 7th day (group Ⅵ) . Conclusions In chronic experiment NO synthesis inhibition can increase pain threshold to laser thermal nociceptive stimulation and induce changes in the affinity and density of NMDA receptor.

Objective To investigate the possible mechanism of direct relaxant effects of propofol on tracheal smooth muscle.Methods Nine Japanese long-ear white rabbits of either sex, weighing 2-3 kg were sacrificed by air embolism. The trachea of each rabbit was removed and cut into six strips of (6-8) mm x (12-15) mm. The tracheal strips were suspended in Kreb' s solution, exposed to 95 % O2 and 5 % CO2 mixture and maintained at 37℃. One end of strip was fixed and the other was connected to a tension monitor through a tension transducer. The experiment was divided into six groups: group I propofol; group Ⅱ propofol + indothelin; group Ⅲp Ⅴ propofol + verapamil and group Ⅵ propofol + glibenclamide. In each group the tracheal strips were precontracted with acetylcholine (10-5 mol? L-1). The strips were then exposed to increasing concentrations of propofol (5 ? 10-3 , 10-2 ,2.5 ? 10-2 , 5 ? 10-2 , 10-1 mg?ml-1 ). At each concentration of propofol, the change in muscle tension was allowed to reach the steady state for 30 min. In group I no other drug was added to the Kreb' s solution besides propofol, while in group Ⅱ-Ⅵ before the effects of propofol were determined, the strips were pretreated with indothelin (10-4 mol? ml-1 ) (in group Ⅱ), L-NAME(10-4 mol?ml-1) (in group Ⅲ), methylene blue (10-5 mol?ml-1) (in group Ⅳ), verapamil (10-5 mol?ml-1) (in group Ⅴ) or glibenclamide (10-5 mol?ml-1) (in group Ⅵ). Results The three concentrations of propofol examined (2.5?10-2, 5?10-2 and 10-1 mg?ml-1) produced relaxation of isolated tracheal smooth muscle. In group Ⅱ , Ⅲ , Ⅳand Ⅴ pretreatment of tracheal strips with indothelin, L-NAME, methylene blue or verapamil did not significantly affect the relaxation of tracheal smooth muscle induced by propofol as compared with group Ⅰ. Pretreatment with glibenclamide significantly depressed the direct relaxant effect of propofol on tracheal smooth muscle ( P