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51.
Velocity data from tissue Doppler imaging (TDI)can provide valuable information on regional leftventricular wallmotion. Validation of TDImyocardialvelocity measurements has been carried out indirectlyfrom gray- scale M- mode images,and discrepancieshave been reported.Mc Dicken[1] and Miyatake etal[2 ]have reported the accuracy and validity of the TDIsystem using a rotating sponge model.However theoverall motion of the heart should be considered.Inthe present study,we described a new TDI… 相似文献
52.
与鼻内镜手术相关的鼻泪管解剖测量 总被引:2,自引:0,他引:2
刘玉欣 《青岛大学医学院学报》2001,37(3):217-218
①目的 熟悉鼻泪管的局部解剖关系 ,为鼻内镜下鼻泪管的手术提供依据。②方法 对 5 6侧正中矢状位切开尸头的鼻泪管进行解剖学测量。③结果 鼻泪管开口位于下鼻道前 1/ 3段顶或侧壁 (30侧 ,2 6侧 )。鼻泪管长度为 (15 .99± 2 .5 2 )mm ,鼻泪管上口径平均 2 .97mm ,鼻泪管中段管径 4.2 0mm ,鼻泪管上口内侧壁厚平均 0 .73mm ,中段内侧壁厚平均 0 .5 5mm ,鼻泪管下口前缘至前鼻棘距离平均 2 1.97mm ,下口前缘至下鼻甲前缘附着处的距离平均为 10 .5 4mm ,上颌窦开口前缘到鼻泪管后壁的距离平均 3.82mm ,鼻泪管长轴与眉间至前鼻棘连线的夹角为 8.74°± 1.39° ,以上各指标左右侧比较差异无显著性 (t =- 0 .983~ 1.481,P >0 .0 5 )。④结论 鼻泪管上口位于鼻丘隆突下缘 ,下口位于下鼻道前端顶或侧壁 ,是鼻内镜鼻腔泪囊造口术的重要标志。 相似文献
53.
The current fourth industrial revolution is a distinct technological era characterised by the blurring of physics, computing and biology. The driver of change is data, powered by artificial intelligence. The UK National Health Service Topol Report embraced this digital revolution and emphasised the importance of artificial intelligence to the health service. Application of artificial intelligence within regional anaesthesia, however, remains limited. An example of the use of a convoluted neural network applied to visual detection of nerves on ultrasound images is described. New technologies that may impact on regional anaesthesia include robotics and artificial sensing. Robotics in anaesthesia falls into three categories. The first, used commonly, is pharmaceutical, typified by target-controlled anaesthesia using electroencephalography within a feedback loop. Other types include mechanical robots that provide precision and dexterity better than humans, and cognitive robots that act as decision support systems. It is likely that the latter technology will expand considerably over the next decades and provide an autopilot for anaesthesia. Technical robotics will focus on the development of accurate sensors for training that incorporate visual and motion metrics. These will be incorporated into augmented reality and visual reality environments that will provide training at home or the office on life-like simulators. Real-time feedback will be offered that stimulates and rewards performance. In discussing the scope, applications, limitations and barriers to adoption of these technologies, we aimed to stimulate discussion towards a framework for the optimal application of current and emerging technologies in regional anaesthesia. 相似文献
54.
A. J. R. Macfarlane M. Gitman K. J. Bornstein K. El-Boghdadly G. Weinberg 《Anaesthesia》2021,76(Z1):27-39
Despite advances in clinical practice, local anaesthetic systemic toxicity continues to occur with the therapeutic use of local anaesthesia. Patterns of presentation have evolved over recent years due in part to the increasing use of ultrasound which has been demonstrated to reduce risk. Onset of toxicity is increasingly delayed, a greater proportion of clinical reports are secondary to fascial plane blocks, and cases are increasing where non-anaesthetist providers are involved. The evolving clinical context presents a challenge for diagnosis and requires education of all physicians, nurses and allied health professionals about these changing patterns and risks. This review discusses: mechanisms; prevention; diagnosis; and treatment of local anaesthetic systemic toxicity. The local anaesthetic and dose used, site of injection and block conduct and technique are all important determinants of local anaesthetic systemic toxicity, as are various patient factors. Risk mitigation is discussed including the care of at-risk groups, such as: those at the extremes of age; patients with cardiac, hepatic and specific metabolic diseases; and those who are pregnant. Advances in the changing clinical landscape with novel applications and settings for the use of local anaesthesia are also described. Finally, we signpost future directions to potentially improve the management of local anaesthetic systemic toxicity. The utility of local anaesthetics remains unquestionable in clinical practice, and thus maximising the safe and appropriate use of these drugs should translate to improvements in patient care. 相似文献
55.
56.
A. Chuan B. Jeyaratnam G. Iohom G. Shorten P. Lee S. Miglani K. Kwofie J. Szerb A. U. Niazi R. Jin T. Jen C. J. McCartney R. Ramlogan the Education in Regional Anaesthesia Collaboration Group 《Anaesthesia》2021,76(7):911-917
The learning curve for novices developing regional anaesthesia skills, such as real-time ultrasound-guided needle manipulation, may be affected by innate visuospatial ability, as this influences spatial cognition and motor co-ordination. We conducted a multinational randomised controlled trial to test if novices with low visuospatial ability would perform better at an ultrasound-guided needling task with deliberate practice training than with discovery learning. Visuospatial ability was evaluated using the mental rotations test-A. We recruited 140 medical students and randomly allocated them into low-ability control (discovery learning), low-ability intervention (received deliberate practice), high-ability control, and high-ability intervention groups. Primary outcome was the time taken to complete the needling task, and there was no significant difference between groups: median (IQR [range]) low-ability control 125 s (69–237 [43–600 s]); low-ability intervention 163 s (116–276 [44–600 s]); high-ability control 130 s (80–210 [41–384 s]); and high-ability intervention 177 s (113–285 [43–547 s]), p = 0.06. No difference was found using the global rating scale: mean (95%CI) low-ability control 53% (95%CI 46–60%); low-ability intervention 61% (95%CI 53–68%); high-ability control 63% (95%CI 56–70%); and high-ability intervention 66% (95%CI 60–72%), p = 0.05. For overall procedure pass/fail, the low-ability control group pass rate of 42% (14/33) was significantly less than the other three groups: low-ability intervention 69% (25/36); high-ability control 68% (25/37); and high-ability intervention 85% (29/34) p = 0.003. Further research is required to determine the role of visuospatial ability screening in training for ultrasound-guided needle skills. 相似文献
57.
58.
Regional anaesthetic techniques are fundamental in the anaesthetic care of orthopaedic patients. They may be used as the primary anaesthetic technique or to provide postoperative pain relief. Compared to general anaesthesia alone, regional techniques can provide superior perioperative analgesia, fewer systemic drug adverse effects such as nausea, vomiting and confusion, and earlier mobilization which can reduce nosocomial complications and facilitate expedited hospital discharge. Disadvantages include block failure, nerve injury, unrecognised injury to the anaesthetised limb, prolonged motor blockade and local anaesthetic toxicity. Preoperative assessment should identify contraindications, document pre-existing neurological deficits, and clarify surgical and perioperative aims. Informed consent should be obtained after a clear explanation of the procedure, its risks, and potential complications. Serious and long-term neurological complications are rare and may be reduced by an awake regional technique, sonographic guidance, regular aspiration and by ensuring low pressure injections. Postoperative follow-up is essential and suspicious neurological findings should be detected, investigated, and managed in an early and timely manner. 相似文献
59.
《Anaesthesia and Intensive Care Medicine》2021,22(12):789-793
The addition of adjuvant agents to intrathecal and epidural anaesthetic techniques is well established, in particular opioids and clonidine. These adjuvants are utilized to improve the quality of anaesthesia and analgesia. Several other adjuvants have been studied but ongoing concerns surrounding safety and efficacy may limit their use in clinical practice. Epinephrine has for many years been administered in combination with local anaesthetic although more recently a diverse range of adjuvants have been added to peripheral nerve block solutions, again with the aim of prolonging surgical anaesthesia. The evidence to support or refute the benefit of these agents is increasing, as is our understanding of which agents have demonstrable efficacy and safety at clinically appropriate doses. Clinicians must be aware that many adjuvants are not licensed for central neuraxial or perineural use and should be aware of the risks, in particular of neurotoxicity and unwanted side effects. 相似文献
60.
CHEN Sheng-li BIN Xiao-nong HUANG Zi-cheng.Department of Interventional Radiology The First Municipal People′s Hospital of Guangzhou Guangzhou Medical College.Guangzhou China 《现代临床医学生物工程学杂志》2007,(4)
目的探讨经支气管动脉灌注化疗(BAI)治疗晚期肺癌近期疗效的影响因素。方法回顾性分析1990年3月至2006年6月间胸部X线片复查资料相对完整的82例经BAI治疗的原发性晚期肺癌的近期疗效。结果完全有效(CR)10例(12.2%)、部分有效(PR)32例(39.0%)、轻微有效(MR)23例(28.0%)、稳定(SD)15例(18.3%)、进展(PD)2例(2.4%)。单因素方差分析结果显示,半月时肿瘤缩小率(TDR1/2month)(χ2=25.92,P<0.01)、BAI次数(TBAI)(χ2=17.70,P<0.01)、肿瘤大小(Tsize)(χ2=14.21,P<0.01)和肿瘤血供丰富程度(χ2=6.59,P<0.01)对近期疗效的影响具有统计学意义。对年龄、病理类型等12项协变量进行二项分类Logistic回归分析,采用向后删除法经10步二次迭代,得到Logistic回归方程:P(1)=1/[1 e-(-8.953 2.656TDR1/2month 1.382TBAI 1.230Tsize)],方程对BAI近期疗效有效与无效的预测正确率分别为85.7%和70.0%。结论第1次BAI后半月时的肿瘤缩小率、BAI治疗次数和肿瘤的大小是影响BAI近期疗效的因素。 相似文献