soda lime). It took significant less time to reach the peak CO concentration with baralyme than with the other two CO2 absorbents. The temperature of top canister went up faster than that of the bottom one with soda lime; whereas with baralyme the temperature of the bottom canister went up faster. Conclusion In a simulated closed circuit the risk of CO poisoning was higher with baralyme than with soda lime. But KOH-free soda lime which still contains NaOH, such as sofnolime, may produce more CO than standard soda lime.

Objective To evaluate the analgesic effect of dexmedetomidine on the ultrasonic guidance brachial plexus block.Methods Sixty patients who underwent elective for one-side upper limb or forearm surgery were selected,they were received ultrasonic guidance brachial plexus block.The patients were divided into observation group and control group by random digits table method with 30 cases each.The observation group received 0.5％ ropivacaine 100 mg and dexmedetomidine 0.75 μg/kg,and the control group received 0.5％ ropivacaine 100 mg alone.The heart rate,mean arterial pressure (MAP),pulse oxygen saturation (SpO2) at the time of entering operating room,brachial plexus block completed,incision and the end of surgery were recorded.After brachial plexus block completed,the visual analogue score (VAS) at the time of incision,1 h during surgery and 1,2,6,12,24,48 h after surgery was recorded.Morphine was given the patients when VAS ＞ 4 scores,and the time to first prescription of morphine and total morphine consumption dose within 48 h after surgery were also detected.The adverse reaction was recorded.Results There were no statistical differences in heart rate and MAP at the time of entering operating room and brachial plexus block completed between the 2 groups (P ＞ 0.05).The heart rate and MAP at the time of incision and the end of surgery in observation group were significantly lower than those at the time of entering operating and the same time of control group,there were statistical differences (P ＜ 0.05).There was no statistical difference in SpO2 between the 2 groups (P ＞0.05).The VAS at the time of 6,12,24 and 48 h after surgery in observation group were significantly lower than those in control group [(3.0 ± 0.9) scores vs.(4.9 ± 0.5) scores,(3.0 ± 0.7) scores vs.(5.6 ± 1.2) scores,(2.2 ± 0.9) scores vs.(4.8 ± 1.8) scores,(1.7 ± 0.5) scores vs.(3.2 ± 1.0) scores],there were statistical differences (P ＜ 0.05).The time to first prescription of morphine in observation group was significantly longer than that in control group [(450 ± 37) min vs.(368 ± 42) min],the total morphine consumption dose was significantly lower than that in control group [(8.3 ± 2.8) mg vs.(15.5 ± 4.5) mg],there were statistical differences (P ＜ 0.05).There was no adverse reaction found.Conclusion Ropivacaine plus 0.75 μ g/kg dexmedetomidine for ultrasonic guidance brachial plexus block may prolong the duration of analgesia,thus reduce morphine consumption within 48 h after surgery without severe adverse reaction.

Objective To evaluate the effects of nicotine or electric vagal stimulation on injury to transplanted lungs in rats.Methods Twenty-four male Wistar rats with transplanted lung,weighing 250-300 g,were randomly divided into 3 groups (n =8 each) using a random number table:control group (group C),nicotine group (group NI) and electric vagal stimulation group (group VS).Nicotine 2 mg/kgwas injected intraperitoneally at 15 min after lung transplantation in group NI.Right cervical vagus nerve trank was stimulated for 20 min with continuous electric rectangular pulses (5 V,2 ms,1 Hz) at 10 min interval twice in total starting from 15 min after lung transplantation in group VS.Arterial blood samples were then collected for blood gas analysis at 15,30,45,75,105 and 135 min after lung transplantation.Arterial blood samples were then collected at 135 min after lung transplantation for determination of the plasma concentration of interleukin-6 (IL-6),IL-8 and tumor necrosis factor-α (TNF-α) by ELISA.The rats were sacrificed at 135 min after lung transplantation and the tissue of transplanted lung was removed for determination of lung injury score (LIS) according to the pathological changes obtained with light microscope,and of wet/dry lung weight ratio (W/D ratio).Results Compared with group C,PaO2 and pH value were significantly increased,and LIS,W/D ratio,and the concentrations of plasma IL-6,IL-8 and TNF-α were decreased in NI and VS groups.Conclusion Nicotine or electric vagal stimulation can attenuate injury to transplanted lungs in rats.

Objective To investigate the effects of inhalation of different concentrations of carbon monoxide (CO) on brain death (BD)-induced lung injury in rats. Methods Thirty-two pathogen free adult male Wistar rats weighing 250-300 g were randomly divided into 4 groups ( n= 8 each): group Ⅰ sham operation (group S);group Ⅱ brain death (group BD) and group Ⅲ and Ⅳ BD + CO 0.025% and 0.050% (group C1, C2 ). The animals were anesthetized and tracheally intubated. Fogarty catheter was inserted into the skull. BD was induced by inflating the balloon slowly at 20 μl/min until apnea developed. The animals were then mechanically ventilated (VT 10 ml/kg, RR 50 bpm, PEEP 2 cm H2O) with 40% O2 in N2 . In group Ⅲ and Ⅳ CO 0.025% and 0.050%were added to the air mixture respectively. In group S the balloon was not inflated. BD was confirmed by apnea,dilated pupils and flat EEG. In group BD,C1 and C2, MAP was maintained at 80-120 mm Hg by norepinephrine infusion. The arterial blood gas analysis was performed before (baseline) and immediately after BD was confirmed (T1) and at 30, 60, 90 and 120 min (T2-5) of CO inhalation. The animals were then sacrificed. The plasma concentrations of IL-6 and TNF-α and the activity of myeloperoxidase (MPO) in the lungs were measured. The W/D lung weight ratio and lung injury score (LIS) were recorded. Results BD significantly decreased PaO2/FiO2, BE and pH while increased plasma IL-6 and TNF-α concentrations, MPO activity in the lungs, the W/D ratio and lung injury score as compared with group S. CO inhalation ameliorated the deleterious effects induced by BD. The antiinfiammatory effect of 0.050% CO was better than that of 0.025 % CO. Conclusion Inhalation of 0.025 % or 0.050% CO can ameliorate BD-induced lung injury in rats, but there is no significant difference in the efficacy.

Objective To analyze the diagnostic utility of combining susceptibility-weighted imaging(SWI)with arterial spin labeling(ASL)in patients with acute ischemic stroke(AIS).Methods Fifty AIS patients who admitted to Yongchuan Hospital,Chongqing Medical University from July 2020 to July 2021 were selected.Scans were performed using a 3.0T MRI scanner,including sequences such as FLAIR,DWI,3D-TOF-MRA,3D-ASL,and SWI.The perfusion status of the infarction core,the grading of draining veins around the infarction core,compensation by collateral circulation,the occurrence of hemorrhagic transformation,and prognosis were assessed.Results The grading of draining veins around the infarction core was significantly correlated with NIHSS scores(r=0.869,P＜0.05)and prognosis(r=0.825,P＜0.05).In addition,significant correlations were found between the perfusion status of the infarction core and the occurrence of hemorrhagic transformation(r=0.873,P＜0.05),compensation by collateral circulation and prognosis(r=0.883,P＜0.05).Conclusion The combination of SWI and ASL provides accurate indications of the hemodynamic conditions around the infarction core in AIS patients,and it can accurately assess the prognosis of AIS patients,contributing valuable information for clinical diagnosis and the selection of treatment strategies.

Objective: To observe the survival and side effects of stereotactic body radiotherapy (SBRT) in large hepatocellular carcinoma (HCC) patients. Methods: Twenty-eight large HCC patients undergoing SBRT in 302 Military Hospital from November 1, 2011 to January 31, 2014 were observed. The prescribed dose was 39-61 Gy/3-9f. Among them, 20 patients simultaneously received transcatheter arterial embolization. The overall survival (OS), progression-free survival (PFS) and local control (LC) rates were calculated by using Kaplan-Meier method. The influencing factors of OS were analyzed by Cox regression model. The influencing factors of radiation-induced liver disease (RILD) were identified by using Logistic regression analysis. Results: The 1-, 2-, 3-and 5-year OS rates were 75%, 57%, 54% and 22%, respectively. The 1-, 2-, 3-and 5-year PFS rates were 59%, 47%, 36% and 18%, respectively. The 1-, 2-, 3-and 5-year LC rates were 92%, 86%, 86% and 86%, respectively. Four patients suffered from RILD and none died from RILD. Child-Pugh classification was the influencing factor of OS and RILD. Conclusion It is preliminarily believed that SBRT is an alternative and safe treatment for patients with large HCC.

Objective:To observe the application effect of BOPPPS combined with scenario simulation in standardized training of residents for "ultrasound-guided regional anesthesia" (UGRA).Methods:The anesthesiology students enrolled in 2019 for standardized resident training were selected as research objects. A total of 44 students were randomly divided into observation group ( n=22) and control group ( n=22). The control group received traditional teaching and the observation group received the BOPPPS combined with scenario simulation teaching. The differences in comprehensive theoretical knowledge and comprehensive ability of UGRA between the two groups were analyzed through the final assessment. The satisfaction of the two groups of students with teaching process was analyzed using the teaching feedback questionnaire. SPSS 20.0 statistical software was used for the t-test, and the non-parametric test was used in cases of unequal variance. Results:Compared with the control group, the observation group showed significantly higher scores of comprehensive theoretical knowledge [(75.86±9.31) points vs. (64.00±7.76)points] and ultrasonic image interpretation [(37.73±4.60) points vs. (30.86±4.57) points] ( P<0.05). Compared with the control group, the observation group showed significantly reduced time of ultrasonic localization of target nerve [(92.00±22.67) seconds vs. (107.32±23.35) seconds] and the puncture time of simulated teaching aids [(67.82±17.83) seconds vs. (103.18±19.15) seconds] ( P<0.05). The overall satisfaction of students was significantly higher in the observation group than in the control group ( P<0.05). Conclusions:The teaching method of BOPPPS combined with scenario simulation is helpful to improve students' comprehensive ability of UGRA such as comprehensive theoretical knowledge, the interpretation of ultrasound image, and the localization of target nerve.

Objective:To analyze the factors influencing radiation-induced liver injury after receiving Cyberknife stereotactic radiotherapy in patients with primary hepatocellular carcinoma.Methods:278 cases with primary hepatocellular carcinoma from July 2016 to April 2019 were prospectively enrolled. Stereotactic radiosurgery with a prescription dose of 48-55gy/5-8 times were given. Liver function, coagulation function, Child-Pugh score, and liver imaging changes were dynamically observed before and after treatment to evaluate the occurrence of radiation-induced liver injury. Logistic regression model was used to analyze the factors influencing radiation-induced liver injury.Results:Among 278 cases, 3 cases of tumor progression were excluded, and a total of 275 cases were included for analysis. The overall survival rate after 8 months of treatment was 100%. Among them, 22 cases were diagnosed as radiation-induced liver injury, with an incidence rate of 8%, and all cases were recovered after symptomatic treatment. Multivariate analysis result suggested that the peripheral white blood cell count was factors influencing the occurrence of radiation-induced liver injury.Conclusion:Cyberknife stereotactic radiotherapy has a low incidence of radiation-induced liver injury in patients with liver cancer, and it is a relatively safe treatment method. Patients with low peripheral white blood cell counts before treatment should be closely monitored for early detection and treatment.