The effects of altering time delays of coupled pacing during acute atrial fibrillation

BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied.     

Association Between Outpatient Follow-Up and Pediatric Emergency Department Asthma Visits

Background. The National Heart, Lung, and Blood Institute (NHLBI) guidelines recommend that patients receive a follow-up outpatient asthma visit after being discharged from an emergency department (ED) for asthma. Objective. To measure the frequency of follow-up outpatient asthma visits and its association with repeat ED asthma visit. Design. We conducted a retrospective cohort study of children with asthma using claims data from a university-based managed care organization from 01 1998 to 10 2000. We performed a multivariate survival analysis using Cox proportional hazards model to determine the effect of follow-up outpatient asthma visits on the likelihood of a repeat ED asthma visit, after controlling for severity of illness, patient age, gender, insurance, and the specialty of the primary care provider. Results: A total of 561 children had 780 ED asthma visits. Of these, 103 (17%) had a repeat ED asthma visit within 1 year. Almost two-thirds of children (66%) did not receive outpatient follow-up for asthma within 30 days of an ED asthma visit. Outpatient asthma visits within 30 days of an ED asthma visit are associated with an increased likelihood (relative risk = 1.80; 95% confidence interval 1.19, 2.72) for repeat ED asthma visits within 1 year. Conclusions. Most patients do not have outpatient follow-up after an ED asthma visit. However, those patients that present for outpatient follow-up have an increased likelihood for repeat ED asthma visits. For the primary care provider, these outpatient follow-up visits signal an increased risk that a patient will return to the ED for asthma and are a key opportunity to prevent future ED asthma visits.     

开放性骨质疏松性股骨远端骨折的治疗和伤害控制论的应用

目的 总结治疗开放性骨质疏松性股骨远端骨折的治疗和应用伤害控制观念的体会。方法 回顾性分析2002年1月～2003年12月60岁以上股骨远端开放性骨折住院治疗的病例21例。应用伤害控制学的原则：全面评价其外伤程度，条件允许则急诊手术，危重患者就临时固定，监护患者的生理指标，限期施行骨折固定手术。结果 17例患者获得超过4个月以上的随访，平均随访7．3个月。17例患者在术后平均15周内(79～168d)达到临床愈合。参照Shelbourne疗效评定标准，膝关节功能优良率达到78％。结论 治疗开放性股骨远端骨质疏松性骨折需要应用伤害控制的观念，兼顾患者全面情况，同时治疗骨质疏松和其它并存疾病。手术固定以股骨髁上逆行交锁髓内钉为主，早期功能锻炼。     

Family Stress and Functioning in Children: the Moderating Effects of Children''s Beliefs About Their Control Over Parental Conflict

While factors such as gender and SES have been studied as moderators of stress for children, their perceptions of control have received little attention. In the current study, children's domain-specific perceptions of their control during marital conflict were investigated as potential moderators of the impact of family stress on children's behavior problems, and perceptions of competence. Ninety-four children aged 6-12 years and mothers from families ranging in level of parental conflict from nondiscordant to discordant to physically violent were interviewed. Multiple regression analyses revealed that higher levels of conflict control beliefs acted as compensatory moderators of stress, being associated with lower levels of problem behaviors across stress levels. However, higher conflict control beliefs acted as vulnerability moderators with regard to children's perceptions of competence.     

Assessment of the quality of life in chronic pancreatitis using Sf-12 and EORTC Qlq-C30 questionnaires

BACKGROUND: SF-12 Health Survey, and European Organisation for Research and Treatment of Cancer Quality of life Questionnaire-C30 are the two main questionnaires proposed and validated for assessing the quality of life in chronic pancreatitis. AIMS: To evaluate the role of the information furnished by both the SF-12 Health Survey and European Organisation for Research and Treatment of Cancer Quality of life Questionnaire-C30 questionnaires, and to determine which of these two questionnaires may be considered more efficacious, in clinical practice, in describing the quality of life of patients with chronic pancreatitis. PATIENTS: We studied 163 consecutive patients with proven chronic pancreatitis. METHODS: The Italian version of the SF-12 Health Survey and the Italian neutral version of the European Organisation for Research and Treatment of Cancer Quality of life Questionnaire-C30 Version 3.0 questionnaires were administered. RESULTS: Pancreatic pain was the only clinical variable able to significantly impair the SF-12 Health Survey component summaries as well as all domains of the European Organisation for Research and Treatment of Cancer Quality of life Questionnaire-C30, while body mass index was positively related to the physical component summary-12 and to the domains of the European Organisation for Research and Treatment of Cancer Quality of life Questionnaire-C30. A high level of reliability of the domains/scores of the two questionnaires in evaluating the quality of life in patients with chronic pancreatitis was found and two main factors were identified. These two factors were mainly related to the two SF-12 Health Survey summary components. CONCLUSIONS: From a practical point of view, the SF-12 Health Survey is more reliable and easier to use in routine clinical practice than the European Organisation for Research and Treatment of Cancer Quality of life Questionnaire-C30.     

躯干运动和负重时对足底支撑面侧向横移的姿势控制

目的:本研究假设自主运动命令和姿势控制信号间有冲突,因此设计在附加重物和不同自主任务的同时给予足底一个模拟受滑的干扰(横移)来观察姿势变化并分析其是否受冲突命令或者力学参数的影响.方法:受试者在执行各种不同的自主任务时,随机给予足底支撑面一个左侧或右侧的横移干扰.这些不同的自主任务包括不负重静止站立、静止站立单手负重5kg、负重5kg站立并躯干静止侧屈15°、负重5kg动态地提重物和放重物5项任务.测量和分析下列参数:中心压力的侧位移(COP)、躯干和股部在冠状面上的角位移和腹内压(IAP).结果:干扰离开质量(向右)、始反应超射的幅度、达到终平衡的时间和达到平衡前COP位移的次数都增加,这种情况可以看作是为了再获得平衡的姿势反应效率降低,因此,如果质量的重力效果能对抗干扰,则再获得平衡的反应效率甚至可以被增进.结论:提重和负重是危害姿势反应效率的因素,因为提重和负重改变了重力效果,加大了对躯干的干扰.在动态条件下躯干的运动不是被横移干扰增强就是被横移干扰抵消,并没有显著地影响改变最终平衡位置姿势校正的效应.因此附加任务的同时给一个支持面上的横移干扰,姿势控制的效应可以被抵消.这个减低的效应可以引起脊柱周围结构的负荷增加和增加受伤的危险性.但是,在恰当地放置负重的位置时,反而可以增进躯干控制和协助恢复姿势平衡.     

Development of integrated provision for pre-fives in the UK

This paper analyses the diverse services currently available for children under five in the UK, and considers the nature of the demand for them. It recounts the initiative made by Strathclyde Region to co-ordinate and integrate pre-five provision, administratively and at a service level. It then considers the efforts of other local authorities to integrate administratively and looks at some of the complexities of attempting to do so at a service level.     

同济医科大学控烟活动及效果评价

我校自1993年开展控烟工作，1995年9月开始创办无吸烟大学校园，采取了卫生宣教和行政干预等综合措施，并进行了效果评价。高强度干预措施实施前期（1995年3月）和中期（1996年10月）相比，男医学生和男女学生平均吸烟率分别从16.3％和11．4％下降到9．6％和5．94％；男教工和男女教工平均吸烟率分别从28．6％和13．8％下降到13．9％和8．86％。     

Incentives for cooperation in quality improvement among hospitals--the impact of the reimbursement system.

Up to now, few analytical models have studied the incentives for cooperation in quality improvements among hospitals. Only those dealing with reimbursement systems have shown that, from the point of view of individual or competing hospitals, retrospective reimbursement is more likely to encourage quality improvements than prospective financing, while the reverse holds for efficiency improvements. This paper studies the incentives to improve the quality of hospital care, in an analytical model, taking into account the possibility of cooperative agreements, price besides non-price (quality) competition and quality improvements that may simultaneously increase demand, increase or reduce costs and spill over to rival hospitals. In this setting quality improvement efforts rise with the rate of prospective reimbursement, while the impact of the rate of retrospective reimbursement is ambiguous, but likely to be negative for quality improvements that are highly cost-reducting and create large spillovers. Cooperation may lead to more or less quality improvement than non-cooperative conduct, depending on the magnitude of spillovers and the degree of product market competition, relative to the net effect of quality on profits and the share of costs that is reimbursed retrospectively. Finally, the stability of cooperative agreements, supported by grim trigger strategies, is shown to depend upon exactly the opposite interaction between these factors.     

The Fort McMurray demonstration project in social marketing: health- and safety-related behaviour among oil sands workers

This is the first round in a series of surveys conducted inFort McMurray as part of the Fort McMurray Demonstration Projectin social marketing. This component of the survey was intendedto focus on the most prominent group of employed workers inthe community and to compare their patterns of response withthe community as a whole. Respondents to the survey were overwhelminglymale (96%), married (72.9%) and living in households of twoto five persons (87.9%). They were predominantly aged 30–44(55%) and graduates of high school (53.5%). Younger male workers(below age 30) were more likely to have a high school diploma(78.3%) or some additional technical or vocational training(21.7% compared to 12.5% overall) and to be unmarried or separated.Attitudes toward safety-related behaviours were stronger thanfor respondents from the community as a whole. Approximately70–100% of all age groups and both sexes showed strongagreement with attitudes involving child car seats and the unacceptabilityof drinking and driving. These attitudes include strong advocacyof vigorous enforcement of occupational health and safety standards.However, they showed a variability similar to the communityas a whole in behaviour at home compared to work, generallyreporting more consistent use of personal protection on thejob than in their own homes, particularly hearing protection.Even so, they were much less likely to perform stretching andwarm-up exercises prior to exertion than community residentsin general. The potential may exist to transfer the technologyand attitudes from workplace health and safety to communitysafety. One possible strategy to accomplish this is to involveworkers in this industry directly in community initiatives.This strategy may be generalizable to any community in whichthere are major employers who place a heavy emphasis on riskcontrol and occupational health and safety.