ObjectiveTo evaluate the changes in the expression of purinergic P2X4 receptor (P2X4R) in spinal cord dorsal horn and dorsal root ganglion in a rat model of acute morphine tolerance or inflammatory pain.MethodsThirty male SD rats were randomly divided into 3 groups:normal saline group (group NS,n =5);acute morphine tolerance group (group M,n =5) and inflammatory pain group (group F,n =20).Inflammatory pain was induced by subcutaneous injection of 4％ formalin 50 μl into the plantar surface of left hindpaw in group F.The animals received intrathecal morphine 10 μg ( 10 μl) once every 2 h for 6 times (T1-6) in group M,while the equal volume of normal saline was given instead in group NS.The rats were then sacrificed 2 h after the last time administration.Paw withdrawal latency (PWL) to a thermal nociceptive stimulus was measured at T1-6 in groups M and NS,or on day 4,7,10 and 14 after establishing the model of inflammatory pain in group F,The rats were sacrificed after measurement of PWL and spinal cord dorsal horn and dorsal root ganglion were removed to detect the expression of P2X4 R by immuno-histochemisty.ResultsCompared with the baseline value,PWL was significantly decreased on day 4-14 after intlammatory pain in group F,and PWL was significantly increased at T1-5,while no significant change was found at T6 in group M ( P ＞ 0.05).Compared with group NS,the expression of P2X4 R was up-regulated in group M,and the expression of P2X4 R was up-regulated on day 4 after inflammatory pain,peaked on day 7 after inflammatory pain,and then was down-regulated gradually on day 10 and 14 after inflammatory pain in group F ( P ＜ 0.01).ConclusionThe expression of purinergic P2Y4 R is up-regulated in spinal cord dorsal horn and dorsal root ganglion in rats with acute morphine tolerance or inflammatory pain,and the change may be related to the development of acute morphine tolerance or inflammatory pain.

Objective To investigate the clinical application of scalp nerve block combined with target-controlled infusion in neurosurgical anesthesia.Methods 40 adult patients undergoing frontotemporal craniotomies were randomly divided into the ropivacaine scalp nerve block group (group R) and control group (group C).The patients in group R received scalp nerve block with 0.5％ ropivacaine before induction while those in group C didnt.We used propofol and remifentanil in target-controlled infusion and atracurium in constant infusion to maintain anesthesia.The heart rate(HR),mean arterial pressure (MAP),bispectral index (BIS) of different time,usage of propofol and remifentanil,extubation time,visual analogue scale,and complication were recorded.Results Both groups had stable hemodynamics.The usage of remifentanil in group R was less than that of group C (t =11.10,P ＜ 0.01).The difference of extubation time,usage of propofol,and incidence of complications were not statistically significant (P ＞ 0.05).The difference of visual analog scale (VAS) (2 hour and 6 hour after operation) was statistically significant (t =5.02,4.60,P ＜0.O1).Conclusions Scalp nerve block combined with target-controlled infusion is simple with less usage of remifentanil and better analgesic effect.

Objective:To explore a multimodal perioperative analgesia plan for patients undergoing microvascular decompression surgery for trigeminal neuralgia.Methods:Eighty patients who underwent microvascular decompression surgery for trigeminal neuralgia admitted to the Xiangya Hospital, Central South University from April 2017 to April 2019 were randomly divided into a nerve block group (group A) and a control group (group C) using a random number table method, with 40 patients in each group. The group A underwent surgical block of the lateral occipital and auricular nerves under ultrasound guidance before induction, with 3 ml of 0.5% ropivacaine used at each site. The group C did not undergo nerve block. Both groups received intravenous injections of midazolam, sufentanil, cisatracurium, etomidate, and lidocaine for anesthesia induction, followed by tracheal intubation and maintenance of anesthesia with propofol and remifentanil. After surgery, an analgesic pump was connected. The total amount of intraoperative use of sufentanil and remifentanil in both groups was recorded, as well as the pain Visual Analogue Scale (VAS) and postoperative anesthesia related complications at 2, 6, 24, and 48 hours after surgery.Resultsl:The total amount of sufentanil and remifentanil used during surgery in the group A was less than that in the group C (all P<0.05). The incidence of postoperative nausea and vomiting in the group A patients was lower than that in the group C ( P<0.05), and the nausea and vomiting score was also lower than that in the group C ( P<0.05). There was no statistically significant difference in the incidence of other postoperative complications (all P>0.05). There was a statistically significant difference in VAS scores between the two groups at 6 hours after surgery ( P<0.05). Conclusions:Occipital and auricular nerve blockade can reduce the amount of opioid drugs used during microvascular decompression surgery in patients with trigeminal neuralgia, thereby reducing the incidence of nausea and vomiting. The postoperative analgesic effect is good.