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21.
Dr Andrzej Sapinski MD 《Journal of clinical monitoring and computing》1994,10(6):373-376
Objective. The objective of this study was to compare blood pressure (BP) measured by the sphygmooscillographic method with that measured by the direct and auscultatory methods.Methods. In 15 adult patients undergoing cardiac surgery, blood pressure was measured by the sphygmooscillographic and direct methods simultaneously on the same upper extremity. In another group of 86 children and 11 adults, blood pressure was measured by the sphygmooscillographic and auscultatory methods simultaneously, with one cuff. For the sphygmooscillographic measurement, we used sphygmomanometer-S, which measures blood pressure on the basis of the amplitude height (oscillometric) and the morphology (sphygmographic) of pulse waves recorded by a transducer placed in the cuff.Results. The systolic and diastolic blood pressure measured by the sphygmooscillographic method were both 2 mm Hg higher than those from the direct method; the mean blood pressure was 0.6 mm Hg higher. These differences were not significant. Compared with the auscultatory method, sphygmooscillographic systolic values were higher by 7 mm Hg, while diastolic values were lower by 9 mm Hg. These differences were significant.Conclusions. Blood pressure measurements obtained by the sphygmooscillographic method correlate well with the direct method for measuring blood pressure in children and adults; but, they do not correlate well with the auscultatory method. 相似文献
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We have developed a simple instrument for pressure algometry. It can be made easily using components found in most anaesthetic rooms. Ten students were able to make the device using written instructions. All the resulting algometers performed within 10% accuracy limits for values up to 4 kgcm−2 . 相似文献
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Sidestream versus mainstream carbon dioxide analyzers 总被引:1,自引:0,他引:1
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我们研究了不同记忆负荷条件下,ERP-P_(300)变化的规律性和特点及ERP-P_(300)与脑力负荷难度之间的关系。在三种脑力作业时,要求受试者记忆2、4、6位随机数字。结果表明,1、随着记忆数字增加,P_(300)波幅相应增大,三种记忆作业P_(300)波幅之间均有显著性差异。2、记忆错误率和记忆难度主观评价值,亦随着记忆数字增加而增大,且在三种记忆作业之间均有显著性差异。3、P_(300)波幅和记忆难度主观评价值之间相关分析表明呈正相关(P<0.01)。我们建议,P_(300)波幅测量可以作为评价脑力负荷的一项客观指标。 相似文献
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The extensometer is a new device with potential in the field of respiratory pattern analysis. This paper describes the physical principles upon which the extensometer depends and also assesses its performance as a noninvasive respiratory monitor in respect of its ability to measure tidal volume and to determine obstructive breathing patterns in awake volunteers in the supine position over a limited time period. Further developments of the device are outlined and the current status of torso transducers in anaesthesia and intensive care are discussed. 相似文献
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The relationship between internal jugular vein diameter as measured with an ultrasound imaging machine (SiteRite, Dymax) and external jugular vein diameter was studied in 50 anaesthetised patients undergoing elective cardiac surgery. There was an inverse correlation between external jugular vein diameter and internal jugular vein diameter ( r = −0.47, p < 0.001). All patients with an external jugular vein diameter of 7 mm or greater had an internal jugular vein diameter of less than 15 mm. No patient with an external jugular vein diameter of less than 7 mm had an internal jugular vein diameter of less than 20 mm. No other patient dimension (height, weight, body mass index, neck circumference) predicted internal jugular vein size. These results suggest that a large external jugular vein (i.e. 7 mm or greater in external diameter) may be associated with a small internal jugular vein. A size 5.0-mm internal diameter tracheal tube may be used to provide a rapid assessment of external jugular vein diameter. 相似文献
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Clinical and laboratory investigations of the relationship of accommodation and convergence function with refractive error 总被引:3,自引:0,他引:3
Studies of the relationship of clinical and laboratory measures of accommodation and convergence function with refractive error are reviewed. There are inconsistencies in results from study to study presumably due, in part, to methodological differences. However, some basic trends can be outlined. In studies in young adults, accommodation in darkness (dark focus), optical reflex accommodation, and proximally induced accommodation are less in myopes than in emmetropes and hyperopes. It also appears that nearpoint esophoria is associated with higher rates of myopia progression in children. Implications for myopia etiology are discussed. 相似文献