Objective To investigate the effects of mild hypothermic cardiopulmonary bypass(CPB) on bax and bcl-2 protein expression and neuronal apoptosis in hippooampus CA1 region in rats. Methods Healthy male SD rats weighing 380-420g were randomly divided into 3 groups: (1)post-CPB 1h group (n=6); (2) post-CPB 6h group (n=6) and (3) sham CPB group(n=5). The animals were anesthetized with intraperitoneal fentanyl 150?g?kg~(-1), midazolam 1 mg?kg~(-1) and vecurunium 0.1 mg?kg~(-1), intubated and mechanically ventilated. Left femoral artery was cannulated for heparinizafion, BP monitoring and blood sampling. Artery in the tail and right jugular vein were cannulated for CPB. The animals in group 1 and 2 underwent 2 h mild hypothermic (26-28℃) CPB at a flow of 160 ml?kg~(-1)?min~(-1). 1h(group 1) and 6h(group 2) after CPB 4% polymerized formaldehyde was injected via the artery in the tail. Brains were immediately removed. Bax and bcl-2 protein expression in hippocampus CA1 region was determined by immuno-histochemistry method and neuronal apoptosis by TUNEL technique. Ultrastructural changes were examined with electron microscope. Results (1)Bax and Bcl-2 protein expressions were significantly higher in group 1(1h after CPB)than in sham CPB group. Bax protein expression was significantly higher but bcl-2 protein expression was significantly lower in group 2 than in group 1. bax/bcl-2 ratio in group 2(at 6h after CPB)was significantly higher than that in group 1(at 1h after CPB). (2) Neuronal apoptosis was significantly increased in group 1 and 2 compared to sham CPB group. (3) Electron microscopy showed that some mitochondria were moderately or severely swollen with vacuolizafion and decreased number of mitochondrial at 1h after CPB and at 6h after CPB there was shrinkage of neuronal cells with irregular shape of nucleus, notches in nuclear membrane and margination of nucleoli. Conclusion CPB induces upregulation of both bax and bcl-2 protein expression with predominance of the pro-apoptotic gene Bax leading to increased neuronal apoptosis, indicating that CPB can cause brain injury.

Objective To investigate the safety of inhalation of isoflurane (ISO) or sevoflurane (SEVO) mixed with nitric oxide (NO) during mechanical ventilation.Methods Thirty-six healthy piglets of both sexes weighing 7-11 kg were randomly allocated to one of 6 groups ( n = 6 each): (1) control group was mechanically ventilated with O2; (2) NO group inhaled 20 ppm NO; (3) ISO group inhaled 1.3 MAC isoflurane; (4) ISO + NO group 1.3 MAC isoflurane + 20 ppm NO; (5) SEVO group inhaled 1.3 MAC sevoflurane and (6) SEVO + NO group inhaled 1.3 MAC sevoflurane + 20 ppm NO. The animals were mechanically ventilated with IPPV (VT 10 ml?kg-1 , RR 30-40 bpm, I: E 1:2) for 4 h in the all 6 groups. The animals were premedicated with atropine 0.02 mg?kg-1 i.m. . The Ⅳ line was established for fluid and drug administration. An additional dose of ketamine 10 mg?kg-1 was given i.v. before tracheostomy. 4F S-G catheter was placed in pulmonary artery via right internal jugular vein for hemodynamic monitoring. Femoral artery was cannulated for BP monitoring and collection of artrerial blood samples. MAP, HR, CVP, right ventricular pressure (RVP), PCWP, MPAP and total compliance of respiratory system (Crs), Paw, VT and PET CO2 were recorded before (T0 ) and at 1, 2, 3, 4 h of ventilation (T1-4). Blood samples were taken at T0 , T2 and T4 for determination of Met Hb and NO2- /NO3- . The animals were killed at the end of 4 h mechanical ventilation and the lungs were removed for determination of wet/dry(W/D) lung weight ratio, broncho-alveolar lavage fluid (BALF) and microscopic examination. BALF was collected for determination of surface tension and concentrations of saturated phosphate (DSPC) , total phosphate (TPL) total protein (TP) and white cell count. Results Crs was significantly decreased at the end of ventilation (T4 ) as compared with the baseline (T0) in group 3,4,5 and 6, while there was no significant change in Crs in group 1 and 2. DSPC/TP was significantly lower in group 3,4,5 and 6 than in group 1 ( P 0.05 ) . Conclusion 1.3 MAC isoflurane or sevoflurane mixed with 20 ppm NO can be used safely during mechanical ventilation.

Objective To compare the neuromuscular blocking effects of rocuronium given by intermittent bolus injection, continuous infusion and target-controlled infusion during liver transplantation. Methods Thirty-six patients with hepatic failure of both sexes aged 21-63 yr weighing 48-80 kg undergoing liver transplantation were studied. The donor livers were obtained from living donors. The patients were divided into 3 groups according to the mode of rocuronium administration ( n = 12 each): group Ⅰ intermittent bolus injection (group Ⅳ); group Ⅱ continuous infusion (group CI) and group Ⅲ target-controlled infusion (group TCI). Neuromuscular block was assessed by TOF stimulation of ulnar nerve (TOF-Watch SX). Anesthesia was induced with midazolam 5 mg,fentanyl 4-6 μg/kg and propofol 1.0-1.5 mg/kg, and rocuronium was administered using different modes of administration. A bolus of rocuronium 0.6 mg/kg was given during induction and supplemental rocuronium 0.15 mg/kg was given when T1 was returned to 25% in preanhepatic stage and T4/T1 (TOFR) returned to 25% in anhepatic and neohepatic stages in group Ⅳ. TCI at an initial target effect-site concentration of 3 μg/ml was started during induction, the concentration was adjusted to maintain T1 at 5%-10% , TCI was temporarily suspended at the beginning of anhepatic and neohepatic stages, and then TCI at a target effect-site concentration of 0.1 μg/ml was started again and the concentration was adjusted to maintain T1 at 5%-10% in group TCI. A bolus of rocuronium 0.6 mg/kg was given during induction, the initial infusion rate was set at 30 μg· kg-1 ·min-1 and then adjusted to maintain T1 at 5%-10% in preanhepatic stage, CI was temporarily suspended at the beginning of anhepatic and neohepatic stages, and then it was started again at 1 μg· kg-1 · min-1 in preanhepatic stage and the infusion rate was adjusted to maintain T1 at 5%-10% in group CI. Tracheal intubation was performed when the maximal effect was achieved. The administration was stopped after suture of the peritoneum. The onset time, the maximal depression of T1 , intubation condition, recovery time and the total amount of rocuronium consumed were recorded.Results There was no significant difference in onset time, the maximal depression of T1, intubation condition,ecovery time and the total amount of rocuronium consumed among the 3 groups ( P ＞ 0.05). Conclusion There is no significant difference in the onset and recovery when neuromuscular blocade was induced by rocuronium via Ⅳ, CI and TCI, but neuromuscular blockade induced by rocuronium via TCI and CI is more stable than that induced by rocuronium via Ⅳ during liver transplantation.

0. 5mv. LAD occlusion was maintained for 50min and then released for reperfusion (120min) . Myocardial infarct size was measured by nitroblue tetrazolam at the end of experiment. Results There was no statistically significant difference in HR, MAP, cardiac output (CO), left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure ( LVEDP) and rate-pressure products ( RPP) among all groups during ischemia and early reperfusion period except for LVEDP in control group which was much higher than that in all preconditioning groups during the late reperfusion period. Compared with the control group, desflurane, sevoflurane, isoflurane and G+ desflurane reduced myocardial infarct size by 41%, 47%,31.7% and 17.8% respectively without significant homodynamic effects. Myocardial infarct size in G + desflurane groups was significantly larger than that in desflurane group. Conclusion Preconditioning with desflurane, sevoflurane and isoflurane reduce myocardial infarct size in rabbits to some extent. The protective effects may be partly medialed via activation of KATP channel.

Objective The study was designed to compare the effects of desflurane and isoflurane on the vecuronium-induced neuromuscular block in the elderly patients. Methods Thirty ASA class I - II elderly patients aged over 70 yr undergoing elective surgery under general anesthesia were randomly divided into 3 groups: desflurane group ( I , n = 10) ; isoflurane group ( II , n = 10) and 3 control group ( III , n = 10). Anesthesia was induced with midazolam 0.02-0.05 mg? kg-1 , propofol 0.5-2.0 mg ? kg-1 and fentanyl 2-5?g? kg-1 maintained with inhalation of 6% desflurane(1 MAC) +50% N2O in oxygen (group I ) or 1.15% isoflurane + 50% N2O in oxygen(group II ) or 50% N2O in oxygen (group III ) supplemented with intermittent iv boluses of propofol and fentanyl when necessary. Neuromuscular block was monitored using accelograph (TOF GUARD , Denmark) .A total dose of vecuronium 40 mg ?kg-1 was divided with 4 equal doses of 10?g ? kg-1 , which was administered accumulatively in each patient. The next dose was given when the effect of the previous dose had reached its peak (T1 was no longer depressed in the height of 3 successive stimuli) .The cumulative dose-response curves of the 3 groups were established. The onset time and maximum depression of T1 of the initial dose and 3 incremental doses were recorded. After the last increment of 10 ?g?kg-1, the time for T1 to returned to 25% ,75% ,90% and TOF ratio(T4/T1) to 70% were recorded. The recovery index was also calculated.Results The demographic data were comparable between the 3 groups. The ED50 and ED95 were significantly lower in desflurane and isoflurane groups than those in control group(P 0.05 ) . The time for T1 to return to 25 % , 75 % and 90 % was significantly longer in desflurane and isoflurane group than that in the control group. The recovery from vecuronium-induced neuromuscular block was slower in desflurane group than that in isoflurane group( P

Objective To investigate the effect of desflurane pretreatment on the density of muscarinic (M)-receptors on anoxic/reoxygenated rat cardiac myocytes. Methods Myocytes were obtained from ventricle of 2-3 day SD rats and incubated for 3 days. Then they were randomly allocated to one of 5 groups: group I received no treatment and served as control ( n = 5); group Ⅱ underwent 2 h hypoxia (liquid culture medium was insufflated with a gas mixture of 1 % CO2 , 1 % O2 and 98% N2) followed by 1h reoxygenation ( n = 6) ; group Ⅲ was pre-treated with 1.5 MAC desflurane (9% ) for 20 min, followed by 10 min washout before the same duration of hypoxia/reoxygenation as in group II ( n = 6) ; group IV underwent longer duration of hypoxia (48 h) followed by 24 reoxygenation ( n = 5) ; group V was pre-treated with 1.5 MAC desflurane (9% ) for 20 min followed by 10 min washout, then underwent longer duration of hypoxia/reoxygenation as in group IV ( n = 5) . The density of M-receptors was measured by the radio-ligand binding assay (RLBA) .Results The density of M-receptors was significantly lower in group Ⅱthan that in group I ( P

Objective To investigate the relationship between cerebral 0, metabolism during coronary artery bypass graft (CABG) performed with cardiopulmonary bypass (CPB) and postoperative mental disorders (POMD) in the elderly.Methods Thirty patients (13 male,17 female) aged 65-76 yr undergoing CABG performed with CPB were studied. Patients with senile dementia were excluded. The patients were premedicated with scopolamine 0.3 mg and pethidine 50mg. Anesthesia was induced with midazolam 0.05-0.1 mg?kg_(-1), propofol 0.2-0.5 mg?g_(-1), fentanyl 10-15?g?g_(-1) and vecuronium 0.1-0.3 mg?g_(-1) and maintained with isoflurane inhalation and intermittent iv boluses of fentanyl. Nasopharyngeal temperature (T) was maintained at 26℃-28℃) during CPB. Radial artery was cannulated for BP monitoring and blood sampling.Swan-Ganz was placed via right internal jugular vein (UV).Another catheter was inserted into right UV and threaded retrogradely until J point for blood sampling. Blood samples were taken from artery and UV simultaneously for blood gas analyses and determination of blood glucose and lactate concentration before anesthesia (T_1 ),immediately after induction of anesthesia (T_2), during splitting of sternum (T_3) when T was reduced to 28℃ (T_4) and rewarmed to 35℃(T_5 ) and at the end of bypass (T_6 ).Cerebral O2 delivery (CDO2 ),cerebral oxygen consumption (CMRO2),cerebral glucose consumption (CMRglu) and lactic acid production (ADVL) were calculated. POMD was assessed using CAM-ICU chart.Results (1)Seven patients developed POMD (7/30 or 23.3% ).(2) Low jugular bulb 02 saturation (SjO2 ≤50% or PjO2≤25% mm Hg) was observed in 8 patients during rewarming. The incidence was significantly higher in POMD patients (3/7 or 42.96%) than that in non-POMD patients (5/23 or 21.74%). (3) CBF/CMRO2 was significantly lower in POMD patients than in non-POMD patients during rewarming.(4) CMRO2/CMRglu was significantly lower but ADVL was significantly higher in POMD patients than in non-POMD patients during hypothermia, rewarming and at the end of CPB.(P

Objective: To compare cumulative dose technique with single dose technique for determining dose-re sponse relationship of rocuronium during balanced anesthesia. Method: Thirty-four ASA grade Ⅰ-Ⅱ patients, aged 23- 65 years, undergoing elective surgery,were randomly allocated to single dose group(n=24) or cumulative dose group (n=10). Single dose group was further divided into 4 subgroups receiving 150,200,250 or 300?g/kg of rocuronium re spectively. In cumulative dose group, the initial dose of 150 or 200 ?g/kg rocuronium was followed by a second dose de termined individually to produce about 90% neuromuscular block. The ulnar nerve was stimulated at the wrist to mea sure the accelography of thumb adduction. The relationship between probit-transformed depression of first twitch height of TOF and the logarithm dose of rocuronium was analysed using linear regression. Result: ED_50 and ED_95 of rocuronium were 193.6?69.1 and 367.2?72. 7?g/kg respectively in single dose group, and 213.0?55.1 and 418.5? 61.7?g/kg respectively in cumulative dose group. No statistically significant differences were found in the slope,inter cept,ED_50 and ED_95 values between two groups. Conclusion: The two-dose cumulative technique can be used as effec tively as traditional single dose technique in determining the dose-response relationship of rocuronium.

ve To compare the effects of coronary-artery-bypass (CAB) surgery with and without cardiopulmonary bypass(CPB) on hemodynamics and the function of the grafts. Methods Thirty-five patients undergoing elective CAB surgery were studied. CAB was performed either with hypothermic CPB (n = 15) or without CPB(off-pump, n = 20) . The patients were premedicated with intramuscular pethidine 50 mg and scopolamine O.3mg. Anesthesia was induced with intravenous midazolam 5-15mg, fentanyl 5-20?g?kg and pancuronium 0.1 mg?kg-1 or pipecuronium 0.1 mg?kg-1 and maintained with iv infusion of fentanyl 6-10?g?kg-1, propofol 2-4mg?kg-1?h-1 and intermittent boluses of pancuronium, midazolam supplemented with 1%-1.5% isoflurane inhalation. In off-pump group naso-pharyngeal T?was maintained at 37.2℃ during operation. The amount of heparin used was equal to about one-third of amount used during CPB and ACT was maintained above 250 seconds. MAP was maintained at 70-90 mm Hg. While blood vessel was being grafted onto the coronary arteries heart rate was maintained at 60-80 bpm, otherwise esmolol 10-20mg was given iv every 5 min until it was satisfactorily controlled. In CPB group, during CPB naso-pharyngeal T?was maintained at 32℃-34℃, MAP at 50-70 mm Hg and blood gases and electrolytes within normal range. Right radial artery was cannulated and 7.5F Swan-Ganz catheter was inserted via internal jugular vein into pulmonary artery for hemodynamic monitoring and blood gas analysis. ECG, SpO2 were continuously monitored during operation. At the end of operation in patients with internal mammary artery used as graft, the flow rate of grafts was measured with 3mm Doppler probe.Results (1) After CAB cardiac index (CT) increased significantly in off-pump group(P0.05) . (3) There was no significant difference in the blood flow of artery graft and myocardial oxygen delivery (MDO2), and consumption ( MVO2) as well as MDO2/MVO2 between the two groups. Conclusions Off-pump CAB surgery has less effects on hemodynamics but systemic and myocardial oxygen delivery and consumption are similar between the two groups.

The pharmacodynamics and its circulatory effects of alcuronium and atracurium were investigated in cardiac and noncardiac surgical patients.The results demonstrated that:l Compared with atracurium group,the duration of action of alcuronium is longer in cardiac patients than that of non-cardiac patients, but there is no difference in the onset of action between these two groups; 2. Half of the patients which received alcuronium need reversal with neostigminel 3. The effects on the circulation of these two drugs were nor remarkable;Therefore,alcuronium is also suitable for cardiac and non-cardiac surgical patients