目的探究超声联合神经刺激仪定位腰丛及坐骨神经阻滞在椎管内麻醉禁忌证患者中的应用效果。方法选取本院2019年6月至2019年10月收治72例的下肢手术患者作为研究对象,随机分为观察组与对照组,各36例。对照组采用全身麻醉,观察组采用超声...目的探究超声联合神经刺激仪定位腰丛及坐骨神经阻滞在椎管内麻醉禁忌证患者中的应用效果。方法选取本院2019年6月至2019年10月收治72例的下肢手术患者作为研究对象,随机分为观察组与对照组,各36例。对照组采用全身麻醉,观察组采用超声联合神经刺激仪定位并麻醉,对比两组患者术后不良反应及疗效。结果观察组患者在阻滞前、阻滞后10 min及30 min MAP及HR比较差异无统计学意义,对照组在阻滞后10 min与30 min HR及MAP均明显低于阻滞前(P<0.05);观察组不良反应发生率(8.33%)明显低于对照组(36.11%)(P<0.05);观察组阻滞完成时间、麻醉起效时间均明显短于对照组(P<0.05),镇痛维持时间明显长于对照组(P<0.05)。结论超声联合神经刺激仪定位腰丛及坐骨神经阻滞效果显著,生理功能干扰小,可在短时间内完成阻滞,快速起效,且镇痛持续时间长,是椎管内麻醉禁忌证患者可用的有效麻醉方法。展开更多
To solve the precision and reliability problem of various machinery equipments and military vehicles, some military organisations, the industrial sector and the academia at home and abroad begin to pay attention to th...To solve the precision and reliability problem of various machinery equipments and military vehicles, some military organisations, the industrial sector and the academia at home and abroad begin to pay attention to the statistical distribution of machining dimensions, material properties and service loads, and the system reliability optimization design with constraints and reliability optimization design of various mechanical parts is studied in this way. However, the above researches focus on solving the strength and the life problem, and no studies have been done on the discrete degree and discrete pattern of other performance indicators. The concept of using a random vector to describe the mechanical parts performance indicators is presented; characteristics between the value of the vector variance matrix determinant and the sum of the diagonal covariance matrix in describing the performance indicators of vector dispersion are studied and compared. A clutch diaphragm spring is set as an example, the geometric dimension indicator is described with random vector, and the applicability of using variance matrix determinant and variance matrix trace of geometric dimension vector to describe discrete degree of random vector is studied by using Monte-Carlo simulation method and component discrete degree perturbation method. Also, the effects of different components of diaphragm spring geometric dimension vector on the value of covariance matrix determinant and the sum of covariance matrix diagonal of diaphragm spring performance indicators vector are analyzed. The present study shows that the impacts of the dispersion of diaphragm spring cone angle on every performance dispersion are all ranked first, and far exceed that of other dimension dispersion. So it must be strictly controlled in the production process. The result of the research work provides a reference for the design of diaphragm spring, and also it presents a proper method for researching the performance of other mechanical parts.展开更多
文摘目的探究超声联合神经刺激仪定位腰丛及坐骨神经阻滞在椎管内麻醉禁忌证患者中的应用效果。方法选取本院2019年6月至2019年10月收治72例的下肢手术患者作为研究对象,随机分为观察组与对照组,各36例。对照组采用全身麻醉,观察组采用超声联合神经刺激仪定位并麻醉,对比两组患者术后不良反应及疗效。结果观察组患者在阻滞前、阻滞后10 min及30 min MAP及HR比较差异无统计学意义,对照组在阻滞后10 min与30 min HR及MAP均明显低于阻滞前(P<0.05);观察组不良反应发生率(8.33%)明显低于对照组(36.11%)(P<0.05);观察组阻滞完成时间、麻醉起效时间均明显短于对照组(P<0.05),镇痛维持时间明显长于对照组(P<0.05)。结论超声联合神经刺激仪定位腰丛及坐骨神经阻滞效果显著,生理功能干扰小,可在短时间内完成阻滞,快速起效,且镇痛持续时间长,是椎管内麻醉禁忌证患者可用的有效麻醉方法。
文摘To solve the precision and reliability problem of various machinery equipments and military vehicles, some military organisations, the industrial sector and the academia at home and abroad begin to pay attention to the statistical distribution of machining dimensions, material properties and service loads, and the system reliability optimization design with constraints and reliability optimization design of various mechanical parts is studied in this way. However, the above researches focus on solving the strength and the life problem, and no studies have been done on the discrete degree and discrete pattern of other performance indicators. The concept of using a random vector to describe the mechanical parts performance indicators is presented; characteristics between the value of the vector variance matrix determinant and the sum of the diagonal covariance matrix in describing the performance indicators of vector dispersion are studied and compared. A clutch diaphragm spring is set as an example, the geometric dimension indicator is described with random vector, and the applicability of using variance matrix determinant and variance matrix trace of geometric dimension vector to describe discrete degree of random vector is studied by using Monte-Carlo simulation method and component discrete degree perturbation method. Also, the effects of different components of diaphragm spring geometric dimension vector on the value of covariance matrix determinant and the sum of covariance matrix diagonal of diaphragm spring performance indicators vector are analyzed. The present study shows that the impacts of the dispersion of diaphragm spring cone angle on every performance dispersion are all ranked first, and far exceed that of other dimension dispersion. So it must be strictly controlled in the production process. The result of the research work provides a reference for the design of diaphragm spring, and also it presents a proper method for researching the performance of other mechanical parts.
