Objective To observe the effect of a variety dosage of dexmedetomidine on circulatory and cognitive func?tions in elderly patients who underwent hip orthopedic surgery. Methods A total of 120 patients who underwent hip ortho?pedic surgery, with age over 65 years old were recruited from 06/2013 to 09/2014 and were administered intravenously dex?medetomidine after epidural anesthesia. Based on the dosage of dexmedetomidine, patients were randomly divided into 3 groups with 40 cases in each group:Group A were given 0.2μg·h-1·kg-1 dexmedetomidine;Group B were given dexmedeto?midine 0.4μg · h-1 · kg-1, and group C were given 0.6μg · h-1 · kg-1. The heart rate (HR),mean arterial pressure (MAP), and pulse oxygen saturation (SpO2) were recorded at 6 time points, including the time entering operating room (T0), 10 min (T1), 20 min (T2) after drug administration, the time of drug withdrawal (T3), 10 min after drug withdrawal (T4) and the terminal time of surgery (T5) respectively. Cognitive function was evaluated by mini-mental state examination (MMSE) at the time points of 24 hours before surgery (t1), 12 hours (t2), 24 hours (t3), and 72 hours (t4) after surgery. Results All 3 groups of pa?tients show no significant difference of MAP, HR and SpO2 at T0 (P>0. 05).A significant decrease in MAP and HR were ob?served in Group C at T2 and T3 time points compared to those in Group A or Group B (P<0.05). There was no significant dif?ference in MMSE at time point T1 among all three groups (P > 0.05). However, compared to that in group A or group C, MMSE increased significantly at time point T2, T3 in group B (P<0.05). In addition, compared to group A or group C, the pa?tients in group B exhibited lower incidence of postoperative cognitive function disorder (P < 0.05). Conclusion Continu?ous intravenous infusion of Dexmedetomidine can be used in elderly patient who underwent hip orthopedic surgery at the dose of 0.4μg·h-1·kg-1 safely with little interference to circulatory and cognitive function in perioperative period.

Objective To evaluate the effect of etomidate on the activity of nuclear factn kappa B (NF-κB) during lung ischemia-reperfusion (I/R) injury in rats.Methods Sixty SPF healthy adult male Sprague-Dawley rats,weighing 180-220 g,were divided into 4 groups (n =15 each) using a random number table:sham operation group (group S),lung I/R group (group I/R),etomnidate group (group E) and fat emulsion group (group F).Lung I/R was induced by 45 min occlusion of the left hilum of the lung followed by 120 min reperfusion.At 3 min before reperfusion,normal saline 1 ml was injccted via the auricular vein in I/R and S groups,and etomidate 0.3 mg/kg and fat emulsion 0.3 mg/kg (diluted to l nl in normal saline) were injected via the auricular vein in E and F groups,respectively.The rats were sac rificed at the end of reperfusion,and the lungs were removed for examination of the pathological changes (using haematoxylin and eosin staining) and for determination of the wet to dry weight ratio (W/D ratio),cell apoptosis (by TUNEL),expression of NF-κB in nucleoprotein (by Western blot) and content of tumor necrosis factor-alpha (TNF-α) in lung tissues (by enzyme-linked immunosorbent assay).Apoptotic index (AI) was calculated.Results Compared with group S,the W/D ratio,AI and content of TNF-α in lung tissues were significantly increased,and the expression of NF-κB in nucleoprotein was up-regulated in group I/R (P＜0.05).Compared with group I/R,the W/D ratio,AI and content of TNF-α in lung tissues were significantly decreased,and the expression of NF-κB in nucleoprotein was down-regulated in group E (P＜0.05),and no significant change was found in the parameters mentioned above in group F (P＞0.05).The pathological changes of the lung were significantly attenuated in group E as compared with group I/R.Conclusion The mechanism by which etomidate reduces lung I/R injury is related to inhibition of NF-κB activity in rats.