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.

AIM: To investigate if pregabalin could depress the acute tolerance induced by morphine when curing the chronic inflammatory pain of rats.METHODS: 24 adult male Sprague-Dawley rats weighing 180-200 g were randomly divided into three groups(8 in each group).Freund's adjuvant was injected subcutaneously in left hind-paw of the rat to establish the chronic inflammatory pain model.3 days later,rats received 3 daily intragastrical(p.o.) morphine 8 mg/kg(M group),pregabalin 3 mg/kg(P group) or morphine 8 mg/kg+pregabalin 3 mg/kg(MP group) administrations respectively.The rats' pressure-withdrawal threshold(PWT) and paw withdrawal thermal latency(PWTL) were determined with Von-Frey hair test and rat hot-plate test respectively.The results of PWT and PWTL before and 15,30,60,120 min after medication were recorded.RESULTS: PWT and PWTL of the rats in M group increased after medication on all the time points of the first day and 15 min of the second day(P

Gabapentin may bind the ? 2? subunit of the voltage -dependent calcium ion channels at the postsynaptic dorsal horn and interrupt t he series of events possibly leading to the experience of a neuropathic pain sen sation. Many clinical studies have clearly demonstrated the efficacy of gabapent in in the treatment of diabetic neuropathy and postherpetic neuralgia. Gabapenti n is considered an effective drug with its minimal side effects and drug interac tions in the management of neuropathic pain syndromes.

Although there are a number of shortcomings with these animal models, they provide important clues in understanding the underlying pathophysiology of neuropathic pain in humans. In these models, cutaneous sensory threshold of the hindlimb ipsilateral to nerve injury is measured. The presence of neuropathic pain in experimental animal models is mainly measured as allodynia or hyperalgesia, in which the normally nonnoxious or mildly noxious stimuli induce a nociceptive behavioral response. This paper mainly discusses the recent findings from the peripheral nerve injury model of neuropathic pain, as well as the different characteristics of these animal models of neuropathic pain.

Objective The double-blinded, randomly study was designed to determine the clinical efficacy and safety of ropivacaine for combined spinal-epidural anesthesia (CSE). Methods Sixty patients, ASA class Ⅰ-Ⅱ , 18 to 75 years, undergoing elective lower limb or perineum surgery, were randomly allocated to receiving spinally hyperbaric mixture 1.5-2ml of 1% ropivacaine (group R, n=20), 0.75% bupivacaine(group B,n=20), or 1% tetracaine (group T,n=20), combined with 10% glucose 1ml and 3% ephidrine 1ml respectively,and the anesthesia was maintained with epidural administration with 2% lidocaine if necessary during the operation ,after the B-D DurasafeTM combined spinal epidural anesthesia kit was applied at the L 3-4 interspace.Results The time to maximum spread of anesthesia in group R was longer, but the recovery time was shorter than those in group T(P0.05). Additionally, as compared with ones in group B and T, the onset of motor block and the time to peak motor block were prolonged significantly (P

Objective A 23-year-old female patient who had a past history of sexual - precocity and fracture developed hyperhyroidism 8 months ago. Radiological examination revealed enlargement of sella turcica and a adrenal gland nodule. The patient was diagnosed to have McCune -Albright syndrome and scheduled for resection of left subtotal adrenalectomy under general anesthesia. The patient was taking (1) thiamazole 5 mg t. i. d. and propranolol 10 mg q. d. for hyperthyroidism; (2) adalat 10 mg t. i. d. and potassium citrate 20 ml t. i. d. for Cushing syndrome and (3) calcium tablets for osteoporosis. Anesthesia was induced with intravenous midazolam 1 mg, fentanyl 50 ?g and vecuronium 1 mg followed by propofol 150 mg and succinyl choline 100 mg. The patient was intubated and mechanically ventilated (VT = 500 ml, RR =10 bpm, I: E = 1 :2) . PET CO2 was maintained between 35 - 45 mm Hg. Anesthesia was maintained with inhalation of isoflurane and N2O - O2 (1:2) and intermittent i.v. boluses of fentanyl and vecuronium. The BP was increased to 180/110 mm Hg after induction of anesthesia. Urapidil 10 mg was given intermittently i.v. During the exploration of adrenal gland BP was again increased to 200/140 mm Hg. Nitroglycerin was infused i.v. and BP was decreased to 120-130/80-90 mm Hg and was kept at this level till the end of operation. Hydrocortisone succinate 100 mg was infused i.v. slowly after operation. The operation went smoothly. The patient was extubated and the postoperative course was uneventful.

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

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.

Objective To evaluate the topical anesthetic effects of compound lidocaine cream ( CLC) coated endo-tracheal tube on the prevention of cough/agitation during extubation in thyroidectomy under general anesthesia . Methods 42 patients scheduled for thyroidectomy in Peking Union Medical College Hospital were continuously en -rolled in this prospective double-blinded randomized controlled trial .Patients were randomized into two groups . Group L were intubated with endotracheal tube coated with CLC , while the control group , group C with liquid par-affin .The end point of study was spontaneous or induced cough /agitation during extubation .Hemodynamic parame-ters and the consumption of opioids were recorded .Patients were followed for major complications during their stay in hospital .Results Spontaneous cough/agitation rate was lower in group L than group C ( 15% vs 65%, P<0.01 );so was induced cough/agitation (35%vs 90%, P<0.001 );the value of SBP ×HR was lower in group L at 1 min after extubation ( P<0.05 ) .Conclusions The topical anesthetic effects of CLC coated endotracheal tube could prevent cough and agitation during extubation in thyroidectomy under general anesthesia .