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31.
J.A. Hannam S.J. Mitchell D. Cumin C. Frampton A.F. Merry M.R. Moore C.J. Kruger 《British journal of anaesthesia》2019,122(2):198-205
Background
Etomidate is frequently selected over propofol for induction of anaesthesia because of a putatively favourable haemodynamic profile, but data confirming this perception are limited.Methods
Patients undergoing cardiac surgery were randomised to induction of anaesthesia with propofol or etomidate. Phase I (n=75) was conducted as open-label, whereas Phase II (n=75) was double blind. Mean arterial blood pressure (MAP) and boluses of vasopressor administered after induction were recorded. The primary endpoint was the area under the curve below baseline MAP (MAP-time integral) during the 10 min after induction. Secondary endpoints were the use of vasopressors over the same period, and the effect of blinding on the aforementioned endpoints. Groups were compared using regression models with phase and anaesthetist as factors.Results
The mean difference between etomidate and propofol in the MAP-time integral below baseline was 2244 mm Hg s (95% confidence interval, 581–3906; P=0.009), representing a 34% greater reduction with propofol. Overall, vasopressors were used in 10/75 patients in the etomidate group vs 21/75 in the propofol group (P=0.38), and in 20/74 patients during the blinded phase vs 11/76 during the open-label phase (P=0.31). The interaction between randomisation and phase (open-labelled or blinded) was not significant for either primary (P=0.73) or secondary endpoints (P=0.90).Conclusions
Propofol caused a 34% greater reduction in MAP-time integral from baseline after induction of anaesthesia than etomidate, despite more frequent use of vasopressors with propofol, confirming the superior haemodynamic profile of etomidate in this context. The proportion of patients receiving vasopressors increased slightly, albeit not significantly, in both groups in the blinded phase.Clinical trial registration
Australian and New Zealand Clinical Trials Registry, ACTRN12614000717651. 相似文献32.
《Journal of pharmaceutical sciences》2019,108(7):2500-2504
Accurately predicting the hepatic clearance of compounds using in vitro to in vivo extrapolation (IVIVE) is crucial within the pharmaceutical industry. However, several groups have recently highlighted the serious error in the process. Although empirical or regression-based scaling factors may be used to mitigate the common underprediction, they provide unsatisfying solutions because the reasoning behind the underlying error has yet to be determined. One previously noted trend was intrinsic clearance-dependent underprediction, highlighting the limitations of current in vitro systems. When applying these generated in vitro intrinsic clearance values during drug development and making first-in-human dose predictions for new chemical entities though, hepatic clearance is the parameter that must be estimated using a model of hepatic disposition, such as the well-stirred model. Here, we examine error across hepatic clearance ranges and find a similar hepatic clearance-dependent trend, with high clearance compounds not predicted to be so, demonstrating another gap in the field. 相似文献
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《中国现代医生》2020,58(34):60-63
目的 通过检测老年轻度认知障碍(MCI)患者血清瘦素(LEP)、甲状腺激素水平,分析其与局部脑血流量(rCBF)的关系。方法 选择本院收治的128 例老年MCI 患者,另选健康者128 例作为对照组。检测血清LEP、甲状腺激素、大脑各区域rCBF 水平并分析其相关性。结果 老年MCI 组患者左右侧额叶、右侧颞叶、左侧顶叶、左右侧基底节区域脑血流量[(43.81±8.62)mL/(100 g·min)、(43.24±7.93)mL/(100 g·min)、(45.14±6.98)mL/(100 g·min)、(45.86±6.77)mL/(100 g·min)、(67.95±8.52)mL/(100 g·min)、(68.36±8.34)mL/(100 g·min)]低于对照组[(46.39±8.31)mL/(100 g·min)、(46.52±8.56)mL/(100 g·min)、(47.37±7.04)mL/(100 g·min)、(48.25±6.98)mL/(100 g·min)、(70.34±8.96)mL/(100 g·min)、(70.58±8.57)mL/(100 g·min)](P<0.05)。老年MCI 组患者血清LEP、T3、FT3 水平[(4.87±1.56)μg/L、(1.21±0.16)nmol/L、(3.04±0.36)pmol/L]低于对照组[(11.45±3.92)μg/L、(1.68±0.21)nmol/L、(4.82±1.21)pmol/L](P<0.05),TSH 水平为(2.78±0.75)IU/mL,高于对照组的(1.13±0.38)IU/mL(P<0.05)。老年MCI 患者血清LEP 水平与左侧额叶、右侧颞叶、左侧顶叶rCBF 呈正相关(r=0.452、0.537、0.544,P 均<0.05),T3 水平与左侧额叶、右侧颞叶rCBF 呈正相关(r=0.427、0.521,P 均<0.05),FT3 水平与右侧颞叶rCBF 呈正相关(r=0.492,P<0.05),TSH 水平与左侧额叶、右侧颞叶rCBF 呈负相关(r=-0.463、-0.489,P 均<0.05)。结论 老年MCI 患者血清中LEP、T3、FT3 水平降低,TSH 水平升高,且与不同区域rCBF 有相关性,可通过调控脑血管功能影响rCBF 变化水平。 相似文献
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38.
《中国现代医生》2020,58(13):97-99+104
目的考察休克指数(shock index,SI)和舒张压(diastolic blood pressure,DBP)对女性产后出血的风险预测效果。方法选取2016年1月~2018年12月在我院行产检并分娩的320例产后出血孕妇作为研究组,另外选取同期进行正常分娩的健康孕妇240例作为对照组,比较两组患者的一般临床资料、血红蛋白(hemoglobin,Hb)、舒张压(diastolic blood pressure,DBP)、收缩压(systolic blood pressure,SBP)、心率(heart rate,HR)及休克指数(shock index,SI),并采用Ordinal逻辑回归分析各参数对产后出血的风险预警。结果两组患者在年龄、孕周、BMI及新生儿体重相比,差异无统计学意义(P0.05),而孕次相比,差异具有统计学意义(P0.05);与对照组产后24 h相比,研究组产后24 h患者的DBP、SBP及Hb均显著降低,而HR和SI显著升高(P0.05);与对照组产前相比,产后24 h患者的SBP、HR及SI显著降低(P0.05);与研究组产前相比,产后24 h患者的DBP、SBP、HR及Hb均显著降低,而SI显著升高,差异具有统计学意义(P0.05);Ordinal逻辑回归分析结果显示,休克指数和舒张压对产后出血具有预警作用(P0.05)。结论休克指数和舒张压可作为评估女性产后出血的风险预测指标,临床应密切监护。 相似文献
39.
导致血不利的原因一是不足,即由于气、血、津、液等物质的缺乏致无源行血;一是不通,即水、湿、痰、饮、瘀、食积、火郁、内风、外伤等病理因素阻滞,致血行不畅。血瘀经脉之内,则水亦瘀积脉中,致脉络胀满,形成水肿。乳腺癌术后患者,金刃本已损伤血脉,术后的放疗、化疗又属祛邪之法,故机体元气受损,气虚无力行血,血运行不畅,导致患侧上肢水肿。故治疗乳腺癌相关淋巴水肿时,应当血水同治,即活血利水之法要贯穿始终。先病血而后病水者,可以活血化瘀为主,利水为辅;先病水后病血者,则以利水消肿为主,酌加活血养血之品。但需要注意的是:①临证时切不可拘泥于单纯的活血利水法,而忽视乳腺癌相关淋巴水肿(breast cancer related lymphedema,BCRL)患者机体本身的状况。②临证勿忽视五脏与血、水的关系,以及肺、脾、肾、三焦与水肿的内在关系。③可多种方法联合运用,审证求因,标本同治。BCRL术后宜补气活血,通脉利水;术后兼化疗者可疏肝健脾、利水消肿;早期可在活血利水基础上,侧重利湿消肿,后期多湿聚为痰,治疗侧重化痰软坚。 相似文献
40.
《Clinical neurophysiology》2020,131(5):1087-1098
ObjectiveFunctional connectivity networks (FCNs) based on interictal electroencephalography (EEG) can identify pathological brain networks associated with epilepsy. FCNs are altered by interictal epileptiform discharges (IEDs), but it is unknown whether this is due to the morphology of the IED or the underlying pathological activity. Therefore, we characterized the impact of IEDs on the FCN through simulations and EEG analysis.MethodsWe introduced simulated IEDs to sleep EEG recordings of eight healthy controls and analyzed the effect of IED amplitude and rate on the FCN. We then generated FCNs based on epochs with and without IEDs and compared them to the analogous FCNs from eight subjects with infantile spasms (IS), based on 1340 visually marked IEDs. Differences in network structure and strength were assessed.ResultsIEDs in IS subjects caused increased connectivity strength but no change in network structure. In controls, simulated IEDs with physiological amplitudes and rates did not alter network strength or structure.ConclusionsIncreases in connectivity strength in IS subjects are not artifacts caused by the interictal spike waveform and may be related to the underlying pathophysiology of IS.SignificanceDynamic changes in EEG-based FCNs during IEDs may be valuable for identification of pathological networks associated with epilepsy. 相似文献