Objective To investigate the effects of intrathecal (IT) dexmedetomidine on analgesia and neurotoxicity produced by ropivacaine spinal block .Methods Male SD rats weighing 250-300 g were used in this study. The animals were anesthetized with intraperitoneal 10% chloral hydrate 300 mg/kg. IT catheter was placed according to the technique described by Yaksh and Rudy. The tip of the IT catheter was positioned at lumbar region. Thirty-six SD rats in which IT catheter was successfully placed without complication were randomly allocated into 6 groups (n = 6 each): group Ⅰ received normal saline IT (group C); group Ⅱ received 0.5% ropivacaine 20 μl IT (group R); group Ⅲ received dexmedetomidine 3 μg/kg IT (group D ); group Ⅳ, Ⅴ , Ⅵ received 0.5% ropivacaine 20 μl + dexmedetomidine 1, 2 and 3 μg/kg IT respectively (group DR1, DR2, DR3). Tail-flick test, paw withdrawal threshold to yon frey stimuli and incline plate test were performed at 5, 30, 60, 120 and 240 min after IT drug administration. Two weeks later, the animals were sacrificed and the lumbar segment of the spinal cord was removed for microscopic examination. Results The duration of spinal block was significantly longer and the effect stronger in group DR1, DR2 and DR3 than in group R. Electron microscope showed that the injury to the myelin sheath of axon was the most severe in group DR3. Little or no damage to the axon was found in the other 5 groups (pathological score = 0). Conclusion Dexmedetomidine IT can enhance spinal block produced by 0.5 % ropivacaine, and there is celling effect.

Objective To research the effect of ulinastatin on T-cytoimmunity in patients with infertility undergoing laparoscopic surgery. Methods Forty patients scheduled for receiving laparoscopic surgery were equally randomized into two groups, ulinastatin group (Group U) and control group (Group C). Ulinastatin was given to patients in the Group U at a dose of 20 × 104 U before anesthetic. No ulinastatin was given to patients in the Group C. Patients′venous blood samples for T-lymphocyte subset (CD3+,CD3+CD4+,CD3+CD8+) and CD3+CD4+/ CD3+CD8+ ratio calculation were collected before the surgery (T0) and at 0 h (T1),1st day (T2),3rd day (T3) after the surgery. Results CD3+ had less difference at T1~3 compared with T0 in the Group C but raised obviously at T2~3 in the Group U. CD3+CD4+ were only raised at T3 compared with T0 but raised obviously at T2~3 in the Group U. CD3+CD8+ were raised obviously at T2~3 compared with T0 in the Group C but had less difference in the Group U. CD3+CD4+/CD3+CD8+ had less difference at T1~3 compared with T0 in the Group C but raised obviously at T3 in the Group U. Conclusion The application of ulinastatin in laparoscopic surgery could significantly produce protective effect on T-cytoimmunity.

Objective The aim of this study was to investigate different dosages and effects of dexmedetomidine for prevention of postanesthetic shivering. Methods One-hundred twenty patients scheduled for laparoscopic surgery were randomly allocated in four groups: before the operation, slowly injected 0.9% normal saline (group S, dexmedetomidine 0.5 μg/kg (group D0.5), dexmedetomidine 0.75 μg/kg (group D0.75), dexmedetomidine 1.0 μg/kg(group D1.0). HR and rectal temperature[C2] were continually monitered during and after operation, time to extubation was measured. Grades of shivering were recorded. Pain evaluation was assessed by a visual analogue scale, sedation was evaluated by Modified Observer′s Assessment of Alertness/Sedation scale. Results The patients in group S showed a significantly higher HR and postoperative incidence of shivering than those in group D0.75 and group D1.0, (P < 0.05). but the extubation time in groupd D0.75 and group D1.0 were longer than patients in group S (P<0.05). Conclusion Slowly injected dexmedetomidine 0.75 μg/kg or 1.0 μg/kg can prevent postanesthetic shivering in laparoscopic surgery effectively.

Objective To examine plasma inflammatory cytokines and assess stress response in different general anesthesia schemes in cesarean operation. Methods Sixty caesarean operation puerperas were randomly divided into two groups, including the group of sevoflurane (Group S) and the group of propofolum (Group P) in 30 cases of each group. At different time point, we recorded the mean arterial pressure and heart rate, text the blood concentration of inflammatory cytokines; The Apgar scores and arteria umbilicalis pH value after baby delivery were recorded. Results The blood pressure and heart rate of the P group after anesthesia induction of baby in delivery were lower than that before the anesthesia induction(P < 0.05). And there were also significant differences when compared with the S group (P < 0.05). The blood concentration of IL-6 and TNF-α of the P group afte operation were higher than that before the anesthesia induction(P < 0.05). There were also significant differences when compared with the S group(P < 0.05). The blood concentration of sTNFRⅡof the P group after operation and 24 hours after the surgery were higher than that before the anesthesia induction (P < 0.05). And there were also significant differences when compared with the S group (P < 0.05). Conclusion Administering Sevoflurane compound with Remifentanil to general anesthesia in Caesarean operation is safty and steady to inhibit stress reaction and prevent explicit memory from the operation.

Objective To investigate the neurotoxic effects of different concentrations of tetracaine and ropivacaine on the brachial plexus nerve in rats.Methods Forty-eight male Sprague-Dawley rats,weighing 410-430 g,were randomly divided into 8 groups (n =6 each):normal saline group (group NS),0.25％,0.50％ and 1.00％ tetracaine groups (groups T1-3 ),and 0.25％,0.50％,1.00％ and 2.00％ ropivacaine groups (groups R1-4 ).The rats received injection of normal saline 1.0 ml,0.25％,0.50％ and 1.00％ tetracaine 0.5 ml,0.25％,0.50％,and 1.00％ ropivacaine 1.0 ml and 2.00％ ropivacaine 0.5 ml in groups NS,T1-3 and R1-4 respectively through one side of the axillary sheath.The other side of the axillary sheath served as control side.Five days later,compound action potential and nerve conduction velocity (NCV) of the brachial plexus nerve were measured.Tne brachial plexus nerve was obtained as the specimen for microscopic examination with light and transmission electron microscope.Results Compared with the control side and group NS,the compound action potential and NCV of the brachial plexus nerve were significantly decreased in groups T2,3 and R3,4 ( P ＜ 0.05 ).The compound action potential and NCV of the brachial plexus nerve were gradually decreased with the increasing concentrations of tetracaine in groups T1 3 ( P ＜ 0.05 ).The compound action potential and NCV of the brachial plexus nerve were significantly decreased in group R4 as compared with groups R1-3 (P ＜ 0.05).The microscopic examination showed that the pathologic changes were more severe in groups T2,3 and R3,4 than those on the control side and than in group NS.Conclusion 0.50％ and 1.00％ tetracaine,and 1.00％ and 2.00％ ropivacaine can result in pathologic damage to the brachial plexus nerve in rats and the degree of damage is related to the concentration.

Objective To studythe labor analgesia effect incombination of water acupuncture andremifen-tanil patient-controlled intravenous analgesia (PCIA) and impact on mother and baby. Methods 90 Ninety sin-gle birth primiparous women were randomly divided into three groups (n = 30), groupⅠ, groupⅡ, groupⅢ. Content of β-endorphin, stress hormone levels,VAS scores were recorded at T0 and T1; adverse circumstance, Apgar score of newborn and neonatal behavioral neurological assessment were recorded. Results Comparing with groupⅢ or T0, at T1 β-EP in the groupⅠwas gone up, while ACTH、 COR and VAS scores were lower in the groupⅠand groupⅡ; adverse circumstance in the groupⅠreduced than that in the groupⅡ. The VAS scores inThe groupⅠand groupⅡand Apgar score and NBNA assessment in three groups were not significantly different. Conclusion Combination of water acupuncture and remifentanil patient-controlled intravenous analgesia iseffec-tive. Ithas no adverse effects on mother and baby. It is an ideal method of labor analgesia.

Objective To evaluation the efficacy of dexmedetomidine mixed with dezocine and levobupivacaine for patient-controlled epidural analgesia (PCEA) after cesarean section.Methods A total of 300 patients, aged 23-35 yr, with body mass index of 24-28 kg/m2 , of American Society of Anesthesiologists physical status Ⅰ or Ⅱ , undergoing elective cesarean section under epidural anesthesia, were randomly divided into 3 groups (n =100 each) according to the random number table: morphine and levobupivacaine group (ML group), dezocine and levobupivacaine group (DL group), and dexmedetomidine, dezocine and levobupivacaine group (DDL group).In group ML, the loading dose included morphine 2 mg + levobupivacaine 10 mg + 5 ml normal saline, and PCEA solution contained morphine 5 mg + levobupivacaine 150 mg + normal saline 100 ml.In group DL, the loading dose included dezocine 3 mg+ levobupivacaine 10 mg+ normal saline 5 ml, and PCEA solution contained dezocine 15 mg + levobupivacaine 150 mg + normal saline 100 ml.In group DDL, the loading dose included dezocine 2 mg+ levobupivacaine 10 mg + dexmedetomidine 0.5 μg/kg + normal saline 5 ml, and PCEA solution contained dezocine 7.5 mg+ levobupivacaine 150 mg + dexmedetomidine 1.5 μ g/kg + normal saline 100 ml.At 10 min before the end of operation, the loading dose was given via the epidural catheter, and the PCEA pump was connected and set up to deliver a 2 ml bolus dose with a 15-min lockout interval and background infusion at 2 ml/h.Analgesia was maintained until 42 h after operation.Visual analog scale score was main-tained ≤ 3, and (or) visual analog scale for fatigue score ≤ 2.When PCEA failed, morphine 2 mg was injected epidurally as rescue analgesic.At 4, 8, 24 and 42 h after operation, the modified Bromage score and Ramsay sedation score were recorded, and patients' satisfaction with analgesia was evaluated.The occurrence of epidural analgesia-related adverse reactions was recorded.Results The consumption of PCEA solution and requirement for rescue analgesics were significantly lower in group ML than in group DL.Compared with group ML, Ramsay sedation score was significantly decreased at 4 and 8 h after operation, the degree of patients' satisfaction with analgesia was increased, and the incidence of nausea, vomiting, dizziness and pruritus was decreased in DL and DDL groups, and the incidence of urinary retention was decreased in group DDL.The degree of patients' satisfaction with analgesia was significantly higher, and the incidence of dizziness and urinary retention was lower in DDL group than in group DL.No patients developed epidural analgesia-relatcd hypotension, bradycardia, or respiratory depression in the three groups.Conclusion The efficacy of dexmedetomidine mixed with dezocine and levobupivacaine is good when used for PCEA after cesarean section, and the adverse reactions are fewer.

Objective To investigate the feasibility and safety of OLV anesthesia about infant lung resection of CCAM by video-assisted thoracicscopy. Methods Endo-tracheal intubation was performed after 43 CCAM infants had undergone rapid intravenous induction. One side of lungs was ventilated by injecting 4 ~ 6 mmHg CO2 for the construction of artificial pneumothorax, and the side lung was compressed forming OLV. SpO2, ECG, MAP, PETCO2, T, PaO2, PaCO2, bleeding volume and urine volume were monitored. The numerical value of SpO2, PaO2, HR, MAP, PETCO2, and PaCO2 were recorded at scheduled intervals. Results Compared with 5min after induction,the PaO2,HR and MAP of the infants significantly reduced; the PETCO2 and PaCO2 significantly increased at OLV at 10 min and 60 min. Compared with OLV at 10 min, the PaO2, PETCO2 significantly increased at OLV 60 min. Conclusion Appropriate respiratory management and drug usage are feasible and safe for infant surgery of CCAM by video-assisted thoracicscopy.

Objective To investigate the protective effect of permissive hypercapnia in infants undergoing one-lung ventilation(OLV). Methods A total of 64 infants were randomly divided into Group N(normocapnia group,n=32)and Group H(hypercapnia group,n=32).Arterial blood gas samples were collected at four differ-ent time points:10 minutes after intubation(T1),30 and 60 minutes after artificial pneumothorax(T2,T3),and 30 minutes after being sent to post anesthesia care unit(T4)while vital signs(HR,MAP,SpO2and temperature) and ventilation parameters(Ppeak,Vt,PEEP,RR,MVV,and FiO2)were recorded simultaneously;OI was calcu-lated by corresponding equation. Bronchoalveolar lavage fluid(BALF)was collected before and after surgery for the measurement of RAGE. Results Compared with those at T1,MAP and PaO2were significantly lower but Ppeak was obviously higher in group N,while HR,Ppeakas well as PaCO2were increased(P<0.05)and Vt,MVV,pH, PaO2as well as lactic acid were decreased in group H(P < 0.05)at T2and T3. Compared with those in group N, MAP,HR as well as PaCO2were higher while Ppeak,Vt,MVV,pH,and lactic acid were lower in group H at T2 and T3(P<0.05).There was a significant increase of RAGE in both groups after surgery and it was much higher in group N when compared with that in group H after surgery(P<0.05). Conclusion PHC not only has advantages in improving tissue oxygenation,but also has the potential of lung protection for infants undergoing OLV.

Objective To explore the effect of protective ventilation strategies based on individualized positive end expiratory pressure(PEEP)regulated by driving pressure(Pd)in infants under OLV.Methods Sixty infants undergoing elective thoracoscopic surgery were randomly divided into the control group and driving pressure group,with 30 cases in each group.The two groups were compared in terms of MAP,HR,tidal volume(Vt),PEEP,Pd,airway peak pressure(Ppeak),and static lung compliance(Cs),and arterial blood gas during OLV before the artificial pneumothorax(T0),10 min(T1),30 min(T2),and 60 min(T3)after the artificial pneumothorax,and right at the end of the artificial pneumothorax(T4).Results There were no significant differences in MAP,HR,and Vt between the two groups at all the time points(P＞0.05).Both groups showed the increase in Pd and Ppeak and decresase in Cs at T1,T2,and T3(all P＜0.05).PaO2 and OI in both group were decreased and PaCO2 was increased at T2(all P＜0.05).Compared with the control group,the driving pressure group presented lower Pd and Ppeak,higher PEEP and Cs at T1,T2,and T3(P＜0.05),and higher PaO2 and OI(P＜0.05)and no significant differences in PaCO2 and FiO2 at T2(P＜0.05).The rate of rescue ventilation during OLV was lower in the driving pressure group(2 cases)than in the control group(9 cases)(6.9%versus 32.4%,P＜0.05).There was no significant difference in the inci-dence of postoperative complications between the two groups(P＜0.05).Conclusion The individualized positive end expiratory pressure(PEEP)regulated by Pd can optimize the PEEP settings upon infant individuals under OLV and improve the compliance and oxygenation of ventilated lung.