BACKGROUND:Traditional analgesia method can relieve the pain after total knee arthroplasty, but the prognosis is poor and drug dependence is strong. Therefore, it is of great significance to study the analgesic drugs in perioperative period of total knee arthroplasty. OBJECTIVE:To explore the analgesic effect of gabapentin combined with continuous femoral nerve block on total knee arthroplasty. METHODS: A total of 48 patients with knee osteoarthritis receiving total knee arthroplasty in the Department of Orthopedics, Affiliated Hospital of Inner Mongolia Medical University from October 2013 to October 2014 were enroled in this study. Using general anesthesia, femoral nerve block was conducted before anesthesia. Analgesia pump was connected after arthroplasty. Patients were randomized to two groups. The control group received multimodal analgesia, and the experimental group received gabapentin combined with continuous femoral nerve block analgesia. Patient’s pain was scored by using resting, activity visual analog scale. Postoperative quality of life, range of motion of knee joint and complications were observed. RESULTS AND CONCLUSION:No significant difference in preoperative resting pain and activity pain was detected between the two groups (P > 0.05). Visual analog scale scores were decreased with time prolonged after arthroplasty in both groups. Visual analog scale scores of resting pain and activity pain were significantly lower in the experimental group than in the control group at 1, 3 and 7 days and 1 month (P < 0.05). Range of motion was significantly larger in the experimental group than in the control group at 3-7 days after arthroplasty (P< 0.05). Activity of daily living score, physical function score, mental function score and social function score were significantly higher in the experimental group than in the control group (P < 0.05). The complication rate was significantly lower in the experimental group than in the control group (17%, 46%,P < 0.05). These data indicate that during perioperative period of total knee arthroplasty, analgesic effect of gabapentin combined with continuous femoral nerve block is ideal. In particular, in patients with acute pain within 48 hours, their combination can promote early rehabilitation of the patient’s knee, and few side effects are found.

Objective To establish a multi-drug resistant model of temporal lobe epilepsy,and then the sodium current of pyramidal neurons in CA1 areas of the hippocampus was used as as index to observe the effect of hippocampal stimulation on pharmacoresistant epileptic rats.Methods Eighty Wistar rats were selected to prepare an amygdaloid kindled model of epilepsy by chronic stimulation of amygaloid basal lateral nucleus.When the kindled model of epilepsy was prepared successfully,the pharmacoresistant epileptic rats were selected according their response to phenobabital and phenytoin.The selected pharmacoresistant epileptic rats were divided into a hippocampal stimulation group (HS group) and a pharmacoresistant control group (PR group).A low-frequency hippocampal stimulation was performed in the HS group,while the PR group received sham stimulation.The whole-cell recording technique by patch-clamp was used to observe the changes of sodium current of hippocampal pyramidal neurons after the hippocampal stimulation.Results Compared with the PR group,the pharmacoresistant epileptic rats in HS group underwent low-frequency stimulation for 2 weeks showed that the amygdale stimulus-induced seizures were decreased (2.32 ± 0.38 in HS group and 4.45 ± 0.42 in PR group,t =84.600,P =0.000) and the parameters of the after-discharges were improved significantly.In HS group,the peak current shifted towards depolarization,the sodium channels were difficult to activate,and were more susceptible to inactivation.Moreover,the recovery time after the sodium channel inactivation was slower in HS group ((17.9 ±0.6) s) than in PR group((16.3 +0.3) s,t =-25.420,P =0.000).Conclusions Hippocampal stimulation may inhibit the sodium channel current of pyramidal neurons in CA1 areas of hippocampus.The mechanism of hippocampal stimulation in the treatment of pharmacoresistant epilepsy might be achieved partly by inhibiting the sodium channel current so as to decrease the excitability of hippocampal neurons.