Obejective To explore the effect of combined use of dexmedetomidine and ultra-low dose naloxone on postoperative hyperalgesia induced by remifentanil. Method 80 ASA gradeⅠ-Ⅱ female patients who were scheduled to perform endoscopic sinus surgery (ESS) were randomly divided into four groups: purely remifentanil group (group R) and remifentanil plus different dosage dexmedetomidine and ultra-low dose naloxone group (group RDN1 ~ RDN3). Then the postoperative VAS on 30 min, 1 h, 2 h, 4 h, 8 h, 12 h and 24 h together with the firstpostoperative pain time , PCA press numbers , fentanyl usage and adverse reaction rate were recorded and evaluated. Results Average VAS of group R are higher than other groups in all 7 time points at the adjusted significant level of 0.0083, and group R > group RDN1 > group RDN2 > group RDN3, while differences between group RDN2 and RDN3 in all time points are not statistical significant.There is no difference between group RDN1 and group RDN2 inthe first postoperative pain time and the PCA press time at 1h after operation. Difference between group RDN2 and group RDN3 in the PCA press time at 24 h after operation was not significant, and the fentanyl usage of RDN groups are significantly less than group R. Conclusions Combined use of dexmedetomidine and ultra-low dose naloxone induced by remifentanil can improving patients′postoperative hyperalgesia , effect increase with the dose of dexmedetomidine increas , and the increasement is more sensitive in acute pain.

Objective To explore the impact of sulfentanyl on sufentanil epidural block during abdominal panhysterectomy. Methods 90 patients scheduled for panhysterectomy were randomly divided into three groups. Tthe control group received epidural administration of 1% ropivacaine of 0.2 mL/kg after 2% idocaine of 3 mL , while the study group 1 received 10μg sufentanil and the study group 2 received 20μg sufentanil in addition to the medications used in the control group. The anesthetic effect, changes in vital signs, and incidence of adverse reactions were compared among the three groups. Results In group S1 and group S2, the onset of epidural anesthesia was faster , time to the highest plane of sensory blockade and time to degree 3 in the Bromag scores were faster , duration of sensory blockade was longer , and OAA/S score was better , as compared with group D , with significant statistical significances (P<0.01);and the effect was better in group S2 than in group S1. There was no difference among the three groups in adverse reactions. MAP , HR and SPO2 were lower in groups S1 and S2 than in group D during the procedure, with a statistical difference (P<0.05). Conclusions Proper dose of sufentanil plays a positive role in ropivacaine epidural block during panhysterectomy , not only increases the onset of anesthesia, but also makes the anesthestic effect better, and has higher safety It is worth popularizing clinically.