Competence,challenges and attitudes of bedside nurses caring for patients with left ventricular assist devices

ObjectivesWe aimed to describe the bedside registered nurses perceived competence, attitudes, and challenges surrounding the management of patients with left ventricular assist devices (LVAD) in the intensive care unit (ICU) and stepdown unit (SDU).Research methodology/designAn exploratory research was employed using a survey.SettingBedside participants were recruited via an electronic recruitment flyer circulated in online professional and social networking sites.Main outcome measuresItems consisted of a numeric rating scale, measuring competence and attitudes related to the management of patients with left ventricular assist devices. The one open-ended question asked the participants to write responses regarding challenges in left ventricular assist device care. Data were analysed using quantitative and qualitative analytics software.ResultsA total of 36 intensive care unit and 35 stepdown unit bedside nurse (n = 71) from six regions of the United States responded. Overall mean scores for competency and attitude domains were ≥ 7.0. Intensive care nurses scored higher in competence and attitude when compared to stepdown unit nurses care of short-term left ventricular assist devices. Competence and attitude were positively associated with years of experience. Five themes related to challenges in care were identified.ConclusionOverall, bedside nurses had satisfactory competence and attitudes surrounding the care of hospitalised left ventricular assist device patients.     

The Hemodynamics of the Berlin Pulsatile VAD and the Role of its MHV Configuration

The 3D flow in a model of the Berlin ventricular assist device (VAD) chamber with monoleaflet valves placed in S-shape conduits was simulated numerically. The blood flow dynamics were described in terms of flow patterns, velocity, pressure, and shear stress. The hemodynamic properties and the VAD's potential risk for thrombosis were evaluated in terms of mixing and washout properties, and global estimations of platelet level of activation (LOA). In order to evaluate the role of valves on the flow in the chamber, the flow in a model with bileaflet valves in straight conduits was simulated and compared with the original case. The results showed that in both models a large rotating flow was developed in the chamber during filling. This vortex filled the entire chamber and moved constantly up to the peak ejection phase, resulting in relatively low shear stress (up to 0.4 Pa) and no lasting stagnation regions. Significant shear stresses were found near the valves with higher values near the outlet valve in both models. The configuration of valves and conduits had a large effect on VAD washout and mixing properties, with advantage to the bileaflet model. However, since the bileaflet valves exhibited higher shear stresses, higher LOA were found for the bileaflet model.     

沙利度胺联合VAD化疗方案治疗多发性骨髓瘤近期疗效观察

目的：观察沙利度胺联合VAD化疗方案治疗多发性骨髓瘤（MM）的近期疗效和不良反应。方法：37例初发MM患者随机分为治疗组和对照组。对照组（17例）单用VAD化疗方案（长春新硷、阿霉素和地塞米松）。治疗组（20例）用沙利度胺联合VAD化疗方案。结果：治疗3个疗程后,治疗组总有效率为80%,对照组总有效率为47.1%,两组比较有显著差异（P〈0.05）。结论：沙利度胺联合VAD化疗方案治疗初发MM的近期疗效优于单用VAD化疗方案,不良反应轻微,易于耐受。     

PD与VAD方案对多发性骨髓瘤的疗效比较

本研究评价PD（硼替佐米、地塞米松）和VAD（长春新碱、阿霉素、地塞米松）两种方案对多发性骨髓瘤的疗效和毒副作用。分别有21和31例多发性骨髓瘤患者纳入PD和VAD治疗组,接受2—5个疗程治疗。所有52例患者中,48例为初治患者,4例曾应用过1—2个疗程M2或MP方案化疗,但未达到部分缓解。在PD组中,完成2、3、4、5个疗程的患者分别为4、4、8、5例;在VAD组中完成2、3、4、5个疗程的患者分别为6、11、12、2例。结果表明：两组患者的反应良好（CR和VOPR）的患者比例在PD组明显高于VAD纽,分别为57．1％和16．1％,差异有显著性意义（P=0．0052）。治疗有效（CR、VGPR和PR）的患者比例在PD和VAD两组中分别为95．2％和74．2％,差异无显著性意义（P=0．1108）。PD组所有患者无1例出现疾病进展,VAD组中有1例疾病进展。两组患者在血液学毒性、肝肾功能损害、周围神经病变、感染、间质性肺炎等主要不良反应发生率相似,差异无统计学意义。结论：与传统的一线治疗方案VAD相比,PD可提高多发性骨髓瘤治疗反应良好的比例,且不增加副反应发生率。     

New treatment strategies for multiple myeloma

During the past 5 years, several new treatments and strategies have been developed for patients with multiple myeloma. For patients with disease resistant to standard therapies, these include the VAD regimen, dexamethasone alone, high-dose melphalan, and intensive chemoradiotherapy with bone marrow transplantation. Alpha interferon appears to have its greatest potential as part of early induction therapy or during remission maintenance. The role of hemopoietic growth factors or blood stem cells in support of high-dose therapy and drugs that may overcome multiple drug resistance continues under study. A sequence of non-cross-resistant therapies early in the disease course seems worthy of investigation, especially in patients at high risk for early relapse.     

Computational Prediction of Hemolysis in a Centrifugal Ventricular Assist Device

Abstract: This paper describes the use of computational fluid dynamics (CFD) to predict numerically the hemolysis in centrifugal pumps. A numerical hydrodynamical model, based on the full Navier-Stokes equation, was used to obtain the flow in a vaneless centrifugal pump (of corotating disks type). After proper postprocessing, critical zones in the channel were identified by means of two-dimensional color-coded maps of %Hb release. Simulation of different conditions revealed that flow behavior at the entrance region of the channel is the main cause of blood trauma in such devices. A useful feature resulting from the CFD simulation is the visualization of critical flow zones that are impossible to determine experimentally with in vitro hemolysis tests.     

Carbazolequinone induction of caspase-dependent cell death in Src-overexpressing cells

We previously reported that RSV-transformed quail neuroretina cells (QNR-ts68) were highly resistant to apoptosis provoked by serum withdrawal, and that this property was due to v-Src kinase activity. The present study investigates the cytotoxic effect and the functional mechanism of carbazolequinone-mediated cell death in this system. QNR-ts68 cells were subjected to carbazolequinone treatment and both growth inhibition and cell death induction were examined using formazan assays. Cell death mechanism (both apoptosis and necrosis) was confirmed through phosphatidyl serine exposure and propidium iodide incorporation. Furthermore, the effect of active carbazolequinone was inhibited by a pan caspase inhibitor. Cytofluorimetric and immunofluorescence data demonstrated the activation of caspase-3 and the involvement of mitochondria. Therefore, this study clearly indicates that carbazolequinones could induce cell death in transformed cells displaying high levels of antiapoptotic tyrosine kinase activity. Further investigations would be necessary to elucidate the mechanisms by which these carbazolequinones act as antitumor agents.     

福建省5岁以下儿童维生素A缺乏流行病学调查

【目的】了解福建省5岁以下儿童维生素A(vitamin A，VA)缺乏现状及其影响因素。【方法】对儿童进行体检、病史询问、膳食调查和血清VA检测。【结果】福建省5岁以下儿童VA亚临床缺乏患病率为6．3％，可疑缺乏患病率为26．3％，未发现有临床表现的VA缺乏。亚临床VA缺乏的患病率存在地区差异，影响VA的缺乏因素有父母的文化程度、职业、家庭经济收入及摄入胡萝卜、深色蔬菜、蛋、动物肝脏、牛奶、水果、鱼肝油的量、近3个月是否有患腹泻、呼吸道感染、贫血等疾病。【结论】采取干预措施来改善儿童VA营养状况是非常必要的，也将是有效的。