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21.
Gregory Guldner MD MS Jason Schultz BS Perry Sexton MD Corwyn Fortner BS Mark Richmond MD 《Academic emergency medicine》2003,10(2):134-139
OBJECTIVES: Physicians commonly use etomidate for adult rapid-sequence intubation (RSI), but the manufacturer does not recommend its use for children under 10 years of age due to a lack of data. The authors present their experience with etomidate for pediatric RSI in order to further develop its risk-benefit profile in this age group. METHODS: Trained abstractors reviewed the medical records for all children under 10 years old who received etomidate for RSI between July 1996 and April 2001. RESULTS: 105 children, with an average age of 3 (+/-2.9) years, received a median dose of 0.32 (+/-0.12) mg/kg of etomidate. The systolic blood pressure increased an average of 4 mm Hg (95% CI = -3.3 to 9.2); the diastolic blood pressure increased 7 mm Hg (95% CI = -3.1 to 11) within 10 minutes of receiving etomidate. The heart rate increased an average of 10 beats/min (95% CI = 4.0 to 17.4). Complications included three patients who vomited within 10 minutes of etomidate administration. There were no cases of documented myoclonus, status epilepticus, or new-onset seizures. Thirty-eight patients received corticosteroids during the hospital course, none for suspected adrenal insufficiency. Three patients died, all from severe brain injury. CONCLUSIONS: In children less than 10 years old, etomidate seems to produce minimal hemodynamic changes, and appears to have a low risk of clinically important adrenal insufficiency, myoclonus, and status epilepticus. The association between etomidate and emesis (observed in less than 3% of enrolled patients) remains unclear. For clinical situations in which minimal blood pressure changes during RSI are critical, etomidate appears to have a favorable risk-benefit profile for children under 10 years old. 相似文献
22.
本研究选择10μg/ml、20μg/ml、40μg/ml浓度的溴氰菊酯处理白纹伊蚊C6/36细胞,以MMC作为阳性对照物,观察溴氰菊酯处理24h后对C6/36细胞染色体畸变率和姐妹染色单体互换(SCE)频率的影响。结果显示,三个浓度的溴氰菊酯对C6/36细胞染色体畸变率均没有显著影响(P<0.05);溴氰菊酯浓度在40μg/ml时可诱导C6/36细胞SCE频率轻度增高(P>0.05),而溴氰菊酯浓度在10μg/ml、20μg/ml时,对C6/36细胞SCE频率没有诱导作用。表明溴氰菊酯对C6/36细胞的遗传学效应较弱 相似文献
23.
The effects of repeated doses of benzodiazepines, diazepam and midazolam in combination with meperidine on arterial blood gases and transcutaneous PO2 were studied in eight healthy volunteers. The study was designed to mimic a clinical situation. Initially two doses of either midazolam 0.05 mg/kg or diazepam in fat emulsion 0.15 mg/kg were given in a randomized crossover fashion with a 20-min interval, followed by meperidine 0.5 mg/kg another 20 min later. The opioid effects were then antagonized by naloxone 0.4 mg. The initial doses of benzodiazepines caused an increase in PaCO2 and a decrease in PaO2. The changes in PaO2 were of short duration and recovered to baseline levels between injections. However, they came sooner and were more pronounced after midazolam. The changes in PtcO2 paralleled those in PaO2. The PtcO2 index as a measure of cardiac output and peripheral blood flow adequacy was increased immediately after the first injection of midazolam but was otherwise not different from control. There were no differences between the drugs concerning PtcO2 index. PaCO2 increased after the first benzodiazepine injection and remained so throughout the study. Addition of meperidine caused only small changes in PaO2 and PaCO2. These changes were reversed by naloxone. In spite of different elimination kinetics there was no difference in the duration of respiratory depression between the two benzodiazepines. 相似文献
24.
目的探讨肥胖患者下腹部手术采用Joel—Cohen切口对预防非感染性切口裂开的临床效果。方法选择切口部位皮下脂肪层厚达4—5cm的妇产科手术患者90例,随机分为观察组44例,采用Joel—Cohen切口;对照组46例,采用下腹正中直切口。观察切口愈合和脂肪液化情况。结果观察组切口甲级愈合率显著高于对照组(P〈0.01);脂肪液化切口裂开率显著低于对照组(P〈0.05)。结论脂肪组织厚达4—5cm以上下腹部手术切口,采用Joel—Cohen切口可以减少脂肪液化,切口愈合显著优于下腹直切口,值得临床推广应用。 相似文献
25.
Summary Bayesian analysis is given of a random effects binary probit model that allows for heteroscedasticity. Real and simulated examples illustrate the approach and show that ignoring heteroscedasticity when it exists may lead to biased estimates and poor prediction. The computation is carried out by an efficient Markov chain Monte Carlo sampling scheme that generates the parameters in blocks. We use the Bayes factor, cross‐validation of the predictive density, the deviance information criterion and Receiver Operating Characteristic (ROC) curves for model comparison. 相似文献
26.
This paper proposes that an individual's self-assessed health (SAH) does not only suffer from systematic reporting bias and adaptation bias but is also biased owing to confounding health norm effects. Using 13 waves of the British Household Panel Survey covering the period 1991–2005, I show that, while there is a negative and statistically significant correlation between SAH and individuals' own health problem index, this negative effect reduces with the average number of health problems per (other) family member. The relative health bias is small, however, which implies that measures of SAH may not suffer seriously from systematic health norm bias. This is an important finding for researchers working with SAH data as it indicates that we do not have to worry too much about controlling for confounding influences from the health of other household members when estimating SAH regression equations. 相似文献
27.
纸本与数字的交互:手机阅读的最佳效果 总被引:1,自引:0,他引:1
顾璟 《南通大学学报(哲学社会科学版)》2008,24(6):137-140
随着全球3G商用的推进和拥有大容量存储能力的智能终端的日益普及,手机正逐步演变成为一个新型的数字阅读终端。利用手机进行电子阅读的全新模式,正以前所未有的普及速度冲击着人们的阅读习惯。而这趋势也逐渐为"阅读"进行重新的定义。对于每一个读者而言,在这样一个信息化的时代里,手机阅读和纸本阅读的交互使用、取长补短,才是获得最佳阅读效果的最有效方式。 相似文献
28.
We focus on the Fisher information matrix used for design evaluation and optimization in nonlinear mixed effects multiple response models. We evaluate the appropriateness of its expression computed by linearization as proposed for a single response model. Using a pharmacokinetic–pharmacodynamic (PKPD) example, we first compare the computation of the Fisher information matrix with approximation to one derived from the observed matrix on a large simulation using the stochastic approximation expectation–maximization algorithm (SAEM). The expression of the Fisher information matrix for multiple responses is also evaluated by comparison with the empirical information obtained through a replicated simulation study using the first‐order linearization estimation methods implemented in the NONMEM software (first‐order (FO), first‐order conditional estimate (FOCE)) and the SAEM algorithm in the MONOLIX software. The predicted errors given by the approximated information matrix are close to those given by the information matrix obtained without linearization using SAEM and to the empirical ones obtained with FOCE and SAEM. The simulation study also illustrates the accuracy of both FOCE and SAEM estimation algorithms when jointly modelling multiple responses and the major limitations of the FO method. This study highlights the appropriateness of the approximated Fisher information matrix for multiple responses, which is implemented in PFIM 3.0, an extension of the R function PFIM dedicated to design evaluation and optimization. It also emphasizes the use of this computing tool for designing population multiple response studies, as for instance in PKPD studies or in PK studies including the modelling of the PK of a drug and its active metabolite. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
29.
To evaluate the long-term effects of entacapone on both mean daily 'on' time and health-related quality of life (QoL) in patients with Parkinson's disease (PD) experiencing 'end-of-dose' motor fluctuations and the benefits of an early therapeutic intervention. A prospective, multicenter, observational, 12-month study was performed with an initial 3-month intervention phase, consisting of a phone call to half of the patients from randomly selected investigators to assess if dose adjustment was necessary. Effectiveness was determined by home diaries ('on' time), subscales II and III of the Unified Parkinson's Disease Rating Scale (UPDRS), and the Parkinson's Disease Questionnaire (PDQ-8). After 3 months of treatment, 4.0% of the intervention group patients discontinued the study, versus 18.4% in the control group ( P < 0.01). The improvement in 'on' time was significantly increased since the 3-month visit (21%, P < 0.0001) until the end of the study (23% at 12 months, P < 0.0001). Entacapone also induced significant reductions in the UPDRS scores for subscales II and III and in the PDQ-8 score. 11.2% of patients experienced at least one adverse reaction. This study confirms the effectiveness of entacapone in reducing motor fluctuations by increasing 'on' time, and in improving QoL of PD patients. An early adjustment of entacapone and levodopa doses reduces the number of treatment discontinuations during the first months of treatment. 相似文献
30.
Inter-study differences: How should they influence the interpretation and analysis of results? 总被引:2,自引:0,他引:2
K R Bailey 《Statistics in medicine》1987,6(3):351-360
In determining the role inter-study variation should play in an overview analysis, it is important to consider three factors: which question one is trying to answer; the degree of similarity or dissimilarity of design, and the degree to which heterogeneity of outcomes can be explained. Three questions one might be interested in are: whether treatment can be effective in some circumstances; whether treatment is effective on average, and whether treatment was effective on average in the trials at hand. Under the assumption of no qualitative interaction, the answers to these questions coincide. The O-E analysis most directly answers the third question. Other analyses are suggested when the first question is of interest, using the aspirin post-MI studies as an example. 相似文献