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21.
充气温控毯用于神经外科手术患者的控温效果 总被引:1,自引:0,他引:1
目的评价充气温控毯用于神经外科手术患者的控温效果。方法40例择期行平卧位脑肿瘤切除术患者,年龄16—65岁,体重41-72 kg,ASAⅠ-Ⅲ级,随机分为2组(n=20):A组,术中充气温控毯24℃风档进行降温,肿瘤切除完毕前30 min进行复温;B组,术中充气温控毯维持中心温度正常(35.2—36.60℃)。均采用气管内静吸复合麻醉,静脉注射异丙酚1.5~2 mg/kg、芬太尼4-6μg/kg、维库溴铵0.1~0.2 mg/kg诱导,吸入0.6%-1.2%异氟醚维持;吸入氧浓度40%;异丙酚1.5~2 mg·kg-1·h-1持续输注;维库溴铵1~2 mg间断静脉注射。每5分钟记录1次中心温度(鼻咽温),观察围术期不良反应及并发症。结果A组2例患者因手术时间超过24 h剔除,共38例进行统计。A组患者降温速率(1.11±0.05)℃/h,复温速率(0.74±0.09)℃/h。A组患者89%(16/18)在硬脑膜打开前达到目标温度34℃,平台期平均中心温度(34.3±0.5)℃,距34℃最大升幅0.52℃,最大降幅为0.23℃。A组患者67%(12/18)手术结束时中心温度恢复正常。返回ICU后A组患者中心温度(返回ICU时实测温度的均值)(35.8±0.6)℃低于B组(36.6±0.4)℃(P<0.05)。A组患者4例术后出现寒颤、3例发热、1例死亡。结论神经外科手术中应用充气温控毯可较理想地降低体温,相对于降温效率其复温效率偏低。 相似文献
22.
23.
目的阐明针刺捻转补法与泻法的操作是否存在效应上的差异,并探讨其效应差异是否为补泻效应的差异.方法应用红外线热像技术,采用不同的捻转补泻手法针刺健康人合谷穴后,观察其在即刻,10、20、30min,对局部皮肤温度的影响.结果不同捻转补法与泻法的操作存在着不同程度的效应差异,其中补法可以使皮温升高,泻法可以使皮温降低,以石氏捻转补泻针法较为明显.结论1)补泻手法,补法和泻法的操作可产生不同的效应.2)不同捻转补泻手法对皮肤温度产生的升降效应为补泻效应,其中以石氏捻转补泻手法最为明显.3)证明补泻手法实施的必要性. 相似文献
24.
25.
目的 探讨长期危险饮酒者血液中平均红细胞体积(MCV)、平均红细胞血红蛋白(MCH)、平均红细胞血红蛋白浓度(MCHC)的变化, 从而对长期危险饮酒提供一个监测参考指标.方法 按世界卫生组织的饮酒分类标准[1]:危险饮酒,男性>14杯/周或1次饮酒>4杯;女性>7杯/周或1次饮酒>3杯(1杯=12 g乙醇,相当于360 ml啤酒,或180 ml葡萄酒,或45 ml 90标准度乙醇饮品).按平均饮白酒>100 ml/d,或饮啤酒>750 ml/d,或葡萄酒>360 ml/d,从本院体检中心选出符合以上条件者116例(A组),非饮酒者126例(B组),然后用全自动血液分析仪对以上两组受试者的MCV、MCH、MCHC 3个指标进行检测,并对两组数据进行了分析和比较.结果 A组与B组的结果比较,两组的MCHC无明显变化,而长期危险饮酒者的MCV、MCH显著升高(P<0.01).结论 红细胞的MCV、MCH的检测可以作为长期危险饮酒的一个监测参考指标. 相似文献
26.
Dr. E. Mietzsch M. Koch M. Schaldach J. Werner B. Bellenberg K. U. Wentz 《Medical & biological engineering & computing》1998,36(6):673-678
The application of spin-echo magnetic resonance imaging sequences on non-invasive temperature imaging for temperature mapping
of human limbs is investigated. In an in vitro expriment performed on a meat sample, the equilibrium magnetisation P and the
spin-lattice relaxation time T1 are calculated from the values for the repetition time TR and the signal intensities obtained by a spin-echo sequence at
different tissue temperatures tures as measured by a fibre-optic probe. T1 is linearly correlated to the tissue temperature, and P is linearly correlated to the reciprocal value of the absolute temperature.
Both effects, taken together, lead to a non-linear dependency of the signal intensity on temperature. Therefore a TR leading
to maximum temperature dependency of the signal intensity is calculated and used in the futher experiments. In the in vivo
experiments, the lower legs of two volunteers are cooled from outside. Images are acquired with a spin-echo sequence (1.5T,
TR=1200 ms, TE=10 ms). A rise in signal intensity in the muscle with falling skin temperature is observed, particularly in
more peripheral muscle layers. This study shows that spin-echo sequences can be used to monitor temperature changes and temperature
differences in living muscle tissue. 相似文献
27.
Effect of Glass Transition Temperature on the Stability of Lyophilized Formulations Containing a Chimeric Therapeutic Monoclonal Antibody 总被引:3,自引:0,他引:3
Purpose. The purpose of this study is to highlight the importance of knowing the glass transition temperature, Tg, of a lyophilized amorphous solid composed primarily of a sugar and a protein in the interpretation of accelerated stability data.
Methods. Glass transition temperatures were measured using DSC and dielectric relaxation spectroscopy. Aggregation of protein in the solid state was monitored using size-exclusion chromatography.
Results. Sucrose formulation (Tg ~ 59°C) when stored at 60°C was found to undergo significant aggregation, while the trehalose formulation (Tg ~ 80°C) was stable at 60°C. The instability observed with sucrose formulation at 60°C can be attributed to its Tg (~59°C) being close to the testing temperature. Increase in the protein/sugar ratio was found to increase the Tgs of the formulations containing sucrose or trehalose, but to different degrees.
Conclusions. Since the formulations exist in glassy state during their shelf-life, accelerated stability data generated in the glassy state (40°C) is perhaps a better predictor of the relative stability of formulations than the data generated at a higher temperature (60°C) where one formulation is in the glassy state while the other is near or above its Tg. 相似文献
28.
甲基强的松龙对低温保存大鼠肝脏的保护作用 总被引:2,自引:1,他引:1
应用Wistar大鼠肝脏离体灌流模型,用CMU—1号液,含有甲基强的松龙的CMU—1号液,以及缺血前预用甲基强的松龙后再用CMU—1号液分别对肝脏进行灌洗保存。检测LDH、ALT、肝组织匀浆SOD活性和MDA含量,并观察肝组织结构。结果表明:甲基强的松龙对低温保存的离体大鼠肝脏具有保护作用 相似文献
29.
G. Dewasmes B. Bothorel A. Hoeft V. Candas 《European journal of applied physiology》1993,66(6):542-546
Summary Thermoregulatory sweating [total body (m
sw,b), chest (m
sw,c) and thigh (m
sw,t) sweating], body temperatures [oesophageal (T
oes) and mean skin temperature (T
sk)] and heart rate were investigated in five sleep-deprived subjects (kept awake for 27 h) while exercising on a cycle (45 min at approximately 50% maximal oxygen consumption) in moderate heat (T
air andT
wall at 35° C. Them
sw,c andm
sw,t were measured under local thermal clamp (T
sk,1), set at 35.5° C. After sleep deprivation, neither the levels of body temperatures (T
oes,T
sk) nor the levels ofm
sw, b,m
sw, c orm
sw, t differed from control at rest or during exercise steady state. During the transient phase of exercise (whenT
sk andT
sk,1 were unvarying), them
sw, c andm
sw, t changes were positively correlated with those ofT
oes. The slopes of them
sw, c versusT
oes, orm
sw, t versusT
oes relationships remained unchanged between control and sleep-loss experiments. Thus the slopes of the local sweating versusT
oes, relationships (m
sw, c andm
sw, t sweating data pooled which reached 1.05 (SEM 0.14) mg·cm–2·min–1°C–1 and 1.14 (SEM 0.18) mg·cm–2·min–1·°C–1 before and after sleep deprivation) respectively did not differ. However, in our experiment, sleep deprivation significantly increased theT
oes threshold for the onset of bothm
sw, c andm
sw, t (+0.3° C,P<0.001). From our investigations it would seem that the delayed core temperature for sweating onset in sleep-deprived humans, while exercising moderately in the heat, is likely to have been due to alterations occurring at the central level. 相似文献
30.
Toe temperature versus transcutaneous oxygen tension monitoring during acute circulatory failure 总被引:1,自引:0,他引:1
Measurements of toe temperature and transcutaneous PO2 (PtcO2) have been both suggested for non-invasive assessment of peripheral blood flow in acute circulatory failure. The underlying
principle of the two methods is that cutaneous vasoconstriction occurs early when tissue perfusion is altered. In 15 patients,
we compared the two measurements during cardiogenic shock (27 measurements) or septic shock (29 measurements). Toe-ambiant
temperature gradient and PtcO2 correlated well together (r=0.66, p(0.001) especially in hyperkinetic septic shock (r=0.79, p(0.001). In cardiogenic shock, toe-ambiant temperature correlated well with cardiac index (r=0.63), stroke index (r=0.64) and oxygen transport (r=0.65), and these correlations were stronger than for PtcO2. In septic shock, both techniques were poor indicators of blood flow indexes but PtcO2 rather correlated with arterial pressure (r=0.66) and left ventricular work (r=0.66). Trend evaluation of data revealed in cardiogenic shock that the increase in toe temperature usually preceded the increase
in PtcO2. Since measurement of PtcO2 is technically more complicated, correlates less well with standard hemodynamic parameters and later reflects cardiovascular
improvement, it has no advantage over measurement of toe temperature in circulatory shock. In cardiogenic shock, measurements
of toe temperature can reliably track cardiac output changes. In septic states, however, non-invasive assessment of skin perfusion
is of limited interest. 相似文献