Objective To evaluate the pharmacokineties of ropivacaine for single sciatic nerve block in dogs.Methods Twelve healthy adult mongrel dogs weighing 14-17 kg were randomized to receive 0.5% ropivaeaine 10 mg/kg or 20 mg/kg for single sciatic nerve block(n=6 each).ECG,BP and HR were monitored and recorded during anesthesia.Blood samples were obtained from femoral artery before ropivacaine injection (baseline)and at 10,20,30,40,60,90,120,150,180,240,360 and 720 min after ropivacaine injeetion for determination of plasma ropivaeaine concentration(by reversc-phasc high performance liquid chromatography).Arterial blood samples were also taken when adverse reactions occurred.The pharmacokinetic parameters were eMeulated with DAS 1.0 software package.Results The concentration-time curve of ropivacaine for single sciatic nenre block was fitted to two-compartment open model in both groups.The peak plasma concentration of ropivaeaine was significantly lower in 10 mg/kg group than in 20 mg/kg group.Two dogs developed convulsion in 20 mg/kg group.The plasma ropivaeaine concentration was 12.56 and 13.67 mg/L respectively during convulsion.Conclusion Pharmaeokinetic profile of ropivaeaine for single sciatic nerve block is best described by two-compartment model.Bopivaeaine 20 mg/kg for sciatic nerve block can hardly be tolerated by dogs.

After first report of local anesthetics on cardiac toxicity was published in 1979, A lot of researches of local anesthetics on the mechanism of cardiac toxicity and its treatments were reported, and some advances were reviewed in this article during recent years.

NMDA(N-Methyl-D-Aspartate)receptor is a kind of ionotropic receptors, which have been widely localized in peripheral somatic tissues and visceral pain pathways. The activation or expression changes of peripheral NMDA receptor may play an important role in pain occurrence. Peripheral administration of NMDA receptor antagonist can alleviate or prevent pain and enhance the analgesic effect of opiate. This method of administration can reduce the side effect of central action induced by the drug. It will be an important research direction of pain management.

As a new laboratory test for evaluation of endogenous pain inhibition,conditioned pain modulation (CPM) deficiency means dysfunction of endogenous pain inhibitory systems and higher incidence of chronic pain.Age,psychological factors and physical activity all seem to influence the individual CPM effect.A standard CPM testing way has an important role in comparison between different researches.

Spinal opioids have been widely used in clinical anesthesia and analgesia. In this article, we reviews the characteristics about the clinical applications of spinal opioids, including the opioid selection, drug dosage, administration route, effects of different opioids, drug combination, associated adverse effects and so on.

5) who were conscious and had no obvious cardio-respiratory and hepato-renal dysfunction were enrolled in this study. The patients received intravenous PCA with morphine for the first 48 hours. The PCIA morphine solution contained morphine 2-6mg?ml-1 and droperidol 1-2 mg?30 ml-1 . PCIA included a bolus dose of morphine 1-3 mg with a 5 min lockout. No background infusion was given. Morphine PCIA was then combined with transdermal fentanyl. The initial dose of transdermal fentanyl was 25?g ? h-1 in the first two to three days. The dose was then gradually increased in 25 ?g?h-1 increments according to VAS scores and the amount of Ⅳ morphine needed to reduce the persistent pain until transdermal fentanyl alone could provide sufficient relief of persistent pain and Ⅳ morphine was given only for breakthrough pain. Pain intensity (VAS scores) before and after treatment, daily consumption of morphine (mg?d-1) and transdermal fentanyl (?g?h-1), vital signs and side effects were recorded.Results The 13 patients included 6 males and 7 females. Their mean (?SD) age was 54?15 yrs and body weight 53? 8 kg. There was positive correlation between the titrated dose of transdermal fentanyl (??k-1) and the initial need of Ⅳ morphine (mg?day-1). Y= 1.3606 X + 6.5088. Persistent pain intensity and breakthrough pain intensity evaluated by VAS scores were significantly reduced during the treatment ( P

0.05] between group L and other two groups.Conclusion PCEA with 0.125% levobupivacaine containing fentanyl 2 ?g?ml-1 provides adequate pain relief after cesarean section with recovery of motor function similar to that with 0.2% ropivacaine and 0.125% racemic bupivacaine.

Objective To investigate the effect of ketamine pretreatment on acute tolerance to morphine in rats with chronic inflammatory pain.Methods Twenty-four adult male SD rats weighing 180-200 g were randomly divided into 3 groups (n=8 each): group Ⅰ morphine (M) ,group Ⅱ ketamine (K) and group Ⅲ ketamine + morphine (KM). Chronic inflammatory pain was induced by subcutaneous injection of Freund's adjuvant 0.125 ml into the plantar surface of left hindpaw. Three days after Freund's adjuvant injection, the animals received intraperitoneal (IP) morphine 5 mg/kg in group M, IP ketamine 10 mg/kg in group K or IP ketamine 10 mg/kg 10 min before IP morphine 5 mg/kg in group KM once a day for 3 consecutive days respectively. The paw withdrawal threshold to yon Frey hair stimulation (PWT) and paw withdrawal latency to noxious thermal stimulation(PWLT) using the hot plate test were measured before Freund's adjuvant injection (T0, baseline), and every day before (T1) and at 15 (T2), 30 (T3), 60 (T4) and 120 min (T5) after medication for 3 days (D1,2,3).Results PWT was significantly increased after medication on D1,2,3 in group KM but only on D1,2 in group M. PWLT was significantly prolonged after medication on D1,2,3 in group KM but only on D1 in group M. Conclusion Ketamine 10 mg/kg pretreatment can decrease the acute tolerance to morphine in rats with chronic inflammatory pain.

Objective To compare the GlideScope video-laryngoscope and Macintosh laryngoscope for double-lumen tube (DLT) intubation.Methods Seventy ASA Ⅰ-Ⅲ patients,aged 18-75 yr,scheduled for thoracic surgery and requiring one-lung ventilation,were randomly divided into 2 groups (n =35 each):Macintosh laryngoscope group (group M) and GlideScope video-laryngoscope group (group G).Anesthesia was induced with propofol,fentanyl and rocuronium.The exposure of glottis obtained with Macintosh laryngoscope and GlideScope video-laryngoscope was assessed using Cormack-Lehane grade.DLT intubation was assisted with Macintosh laryngoscope or GlideScope video-laryngoscope.The Cormack-Lehane grade,difficulty of DLT placement,and reverse DLT placement were recorded.The success rate of DLT placement at first attempt and intubation time were also recorded.Blood pressure and heart rate were recorded before intubation and at 0 and 3 min after intubation.The postoperative side effects were recorded.Results Compared with M group,the intubation time was significantly prolonged,the difficulty of DLT placement and blood pressure at 0 and 3 min after intubation were increased in G group (P ＜ 0.05).There was no significant difference in the success rate of DLT placement at first attempt,rate of reverse DLT placement,Comark-Lehene grade and heart rate at each time point between the two groups (P ＞0.05).The Comark-Lehene grade obtained with GlideScope video-laryngoscope was superior to that obtained with Macintosh laryngoscope in G group (P ＜ 0.05).Conclusion GlideScope video-laryngoscope can provide a better exposure of glottis and improvement in the intubating conditions,but the method is more complex and the response to intubation is stronger than Macintosh laryngoscope for DLT intubation.

Objective To investigate the safety and feasibility of anesthesia for patients with myasthenia gravis using target controlled infusion without muscle relaxant.Methods Thirty-one patients with myasthenia gravis were recruited into study.A target controlled infusion was started with targeting effect-site concentration of propofol 3 μg/mL and remifentanil 4 ng/mL.Intubation was performed when patients were unconsciousness and target concentrations of both drugs were reached.No muscle relaxant was used during anesthesia.Blood pressure,heart rate,performance of intubation and respiratory recovery including extubation and wake time were observed.Results All patients were intubated successfully in one attempt.38.7% patients had mild cough when the endotracheal tube past through the vocal cord during intubation.Blood pressure and heart rate at post-intubation increased significantly as compared with pre-intubation (P＜0.01).After cease of drugs,time of spontaneous breathing recovery was (6.5±2.9) min.Extubation and wakeup time were (9.8±3.6) and (7.4±3.1) min respectively.No adverse event was noted.Conclusion Target controlled infusion without muscle relaxant was safe and effective anesthesia for myasthenia gravis patients undergoing thymectomy.