目的比较超声引导下采用不同浓度罗哌卡因行收肌管阻滞(ACB)对全膝置换术(TKA)后镇痛效果及股四头肌肌力的影响。方法选取拟在喉罩全麻下行单侧膝置换手术患者60例,男33例,女27例,年龄50~75岁,BMI 17~25 kg/m^2,ASAⅠ-Ⅲ级,随机分为三组...目的比较超声引导下采用不同浓度罗哌卡因行收肌管阻滞(ACB)对全膝置换术(TKA)后镇痛效果及股四头肌肌力的影响。方法选取拟在喉罩全麻下行单侧膝置换手术患者60例,男33例,女27例,年龄50~75岁,BMI 17~25 kg/m^2,ASAⅠ-Ⅲ级,随机分为三组:0.25%罗哌卡因组(R1组)、0.375%罗哌卡因组(R2组)和0.5%罗哌卡因组(R3组),每组20例。患者均于术毕即刻于超声下行术侧ACB。记录术后4、8、12、24、48 h静息和运动时的VAS评分,记录术前1 d、术后4、8、12、24、48 h的股四头肌肌力分级,记录术前1 d、术后24、48 h膝关节活动度(ROM),并记录术后48 h内PCIA内舒芬太尼使用量,补救镇痛次数,恶心呕吐、尿潴留等并发症的发生情况。结果与术后4 h比较,术后12、24、48 h R1组静息和运动VAS疼痛评分明显升高(P<0.05)。与R1组比较,术后12、24、48 h R2、R3组静息和运动VAS疼痛评分明显降低(P<0.05)。与术前1 d比较,术后4、8、12、24 h R1组、R2组股四头肌肌力明显降低(P<0.05);术后4、8、12、24、48 h R3组股四头肌肌力明显降低(P<0.05)。与R3组比较,术后48 h R1组、R2组股四头肌肌力明显升高(P<0.05)。与术前1 d比较,术后24、48 h三组ROM明显降低(P<0.05);与R1组比较,术后24、48 h R2、R3组ROM明显升高(P<0.05)。与R1组比较,R2、R3组术后48 h内PCIA内舒芬太尼使用量明显减少,补救镇痛率、恶心呕吐和尿潴留发生率明显降低(P<0.05)。结论全膝关节置换术后镇痛采用0.375%罗哌卡因收肌管阻滞较0.25%浓度镇痛效果明显,减少术后阿片类药物使用量及并发症,较0.5%浓度有更强的股四头肌肌力及更高的膝关节活动度,有助于患者的术后快速康复。展开更多
A novel approach,which can be used for dynamic characteristics analysis of machine tools based on unit structure(US),is reported in this paper.The concepts of unit structures for design of machine tools are defined.In...A novel approach,which can be used for dynamic characteristics analysis of machine tools based on unit structure(US),is reported in this paper.The concepts of unit structures for design of machine tools are defined.In order to satisfy the dynamic characteristics requirement of high natural frequency and light-weight of US,a design method of multi-disciplinary optimization of NSGA-II about unit structures driven by natural frequency and mass is developed.Through analyzing the unit structures,key factors affecting the natural frequency and mass are extracted,and the mathematical models of natural frequency and mass about unit structures are also established by using central composite design and response surface model.The goal of high natural frequency and light-weight is reached by using the multi-objective genetic algorithms.The Pareto optimal set is also obtained.The dynamic behavior of US is investigated by the experimental modal analysis.To show the efficiency of the proposed novel method,the example of YKW51250 gear shaping machine bed is used.Through optimization of NSGA-II about US of YKW51250 machine bed,the natural frequency of YKW51250 gear shaping machine bed is increased by 30.4%and its mass decreased by 5.2%comparing with the original design.By studying the dynamic characteristics of the simplified machine tools bed,useful laws are obtained,and these laws can be used in primary design of NC machine tools structures.The optimal method based on US can be also applied to the dynamic optimal design of machine tools and other similar equipments.展开更多
文摘目的比较超声引导下采用不同浓度罗哌卡因行收肌管阻滞(ACB)对全膝置换术(TKA)后镇痛效果及股四头肌肌力的影响。方法选取拟在喉罩全麻下行单侧膝置换手术患者60例,男33例,女27例,年龄50~75岁,BMI 17~25 kg/m^2,ASAⅠ-Ⅲ级,随机分为三组:0.25%罗哌卡因组(R1组)、0.375%罗哌卡因组(R2组)和0.5%罗哌卡因组(R3组),每组20例。患者均于术毕即刻于超声下行术侧ACB。记录术后4、8、12、24、48 h静息和运动时的VAS评分,记录术前1 d、术后4、8、12、24、48 h的股四头肌肌力分级,记录术前1 d、术后24、48 h膝关节活动度(ROM),并记录术后48 h内PCIA内舒芬太尼使用量,补救镇痛次数,恶心呕吐、尿潴留等并发症的发生情况。结果与术后4 h比较,术后12、24、48 h R1组静息和运动VAS疼痛评分明显升高(P<0.05)。与R1组比较,术后12、24、48 h R2、R3组静息和运动VAS疼痛评分明显降低(P<0.05)。与术前1 d比较,术后4、8、12、24 h R1组、R2组股四头肌肌力明显降低(P<0.05);术后4、8、12、24、48 h R3组股四头肌肌力明显降低(P<0.05)。与R3组比较,术后48 h R1组、R2组股四头肌肌力明显升高(P<0.05)。与术前1 d比较,术后24、48 h三组ROM明显降低(P<0.05);与R1组比较,术后24、48 h R2、R3组ROM明显升高(P<0.05)。与R1组比较,R2、R3组术后48 h内PCIA内舒芬太尼使用量明显减少,补救镇痛率、恶心呕吐和尿潴留发生率明显降低(P<0.05)。结论全膝关节置换术后镇痛采用0.375%罗哌卡因收肌管阻滞较0.25%浓度镇痛效果明显,减少术后阿片类药物使用量及并发症,较0.5%浓度有更强的股四头肌肌力及更高的膝关节活动度,有助于患者的术后快速康复。
基金partially supported by the Leading Talent Project of Guangdong Province of Chinathe National Key S&T Special Projects of China on CNC machine tools and fundamental manufacturing equipments(Grant No.2010ZX04001-191 and 2011ZX04002-032)
文摘A novel approach,which can be used for dynamic characteristics analysis of machine tools based on unit structure(US),is reported in this paper.The concepts of unit structures for design of machine tools are defined.In order to satisfy the dynamic characteristics requirement of high natural frequency and light-weight of US,a design method of multi-disciplinary optimization of NSGA-II about unit structures driven by natural frequency and mass is developed.Through analyzing the unit structures,key factors affecting the natural frequency and mass are extracted,and the mathematical models of natural frequency and mass about unit structures are also established by using central composite design and response surface model.The goal of high natural frequency and light-weight is reached by using the multi-objective genetic algorithms.The Pareto optimal set is also obtained.The dynamic behavior of US is investigated by the experimental modal analysis.To show the efficiency of the proposed novel method,the example of YKW51250 gear shaping machine bed is used.Through optimization of NSGA-II about US of YKW51250 machine bed,the natural frequency of YKW51250 gear shaping machine bed is increased by 30.4%and its mass decreased by 5.2%comparing with the original design.By studying the dynamic characteristics of the simplified machine tools bed,useful laws are obtained,and these laws can be used in primary design of NC machine tools structures.The optimal method based on US can be also applied to the dynamic optimal design of machine tools and other similar equipments.
