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This paper aims to determine whether the rank order of hospitals changes when their central line‐associated bloodstream infection (CLABSI) rate is computed using a traditional proxy measure for the denominator (number of patients with one or more catheter in place) versus using the actual number of catheters or catheter‐lumens.

The authors conducted a statewide voluntary one‐day prevalence survey among all hospitals participating in Washington State's mandatory public reporting program. Hospitals counted the number of catheters and catheter‐lumens as well as patients with catheters. Counts of patients with one or more catheter in place, of catheters, and of catheter‐lumens were extracted from each hospital's completed survey form and transformed into a ratio. Three CLABSI incidence density rates were computed for each hospital by scaling their annual CLABSI rate in the previous calendar year by the ratio of patients to catheters to catheter‐lumens. Influence of these three different denominators on rank order of the hospitals was assessed by scaling the corresponding Centers for Disease Control and Prevention's National Healthcare Safety Network incidence density rates for each participating hospital and examining position shifts with the Wilcoxon signed rank test.

Statistically significant but only modest shifts in position became evident, which did not correlate with service complexity characteristics of the hospitals affected.

Others have shown that the CLABSI incidence density rate in a single hospital is significantly affected by switching from a traditional proxy measure denominator to a more meaningful denominator. This is the first report on whether all hospitals' rates would be affected in a uniform or a non‐uniform manner if a different denominator were to be selected by mandatory public reporting programs.

Healthcare-associated infections (HAIs) are a major cause of concern because of the high levels of associated morbidity, mortality, and cost. In addition, children and intensive care unit (ICU) patients are more vulnerable to these infections due to low levels of immunity. Various medical interventions and statistical process control techniques have been suggested to counter the spread of these infections and aid early detection of an infection outbreak. Methods such as hand hygiene help in the prevention of HAIs and are well-documented in the literature. This chapter demonstrates the utilization of a systems methodology to model and validate factors that contribute to the risk of HAIs in a pediatric ICU. It proposes an approach that has three unique aspects: it studies the problem of HAIs as a whole by focusing on several HAIs instead of a single type, it projects the effects of interventions onto the general patient population using the system-level model, and it studies both medical and behavioral interventions and compares their effectiveness. This methodology uses a systems modeling framework that includes simulation, risk analysis, and statistical techniques for studying interventions to reduce the transmission likelihood of HAIs.

Public procurement has been increasingly seen as an important innovation policy tool. One neglected aspect of the public procurement of innovation is, however, diffusion. The purpose of this paper is to counter this neglect by exploring how institutional coordination may affect the diffusion of innovations procured by a public agency.

A case study including semi‐structured interviews and the consulting of different documents were used to study how institutions and institutional coordination affect the adoption and diffusion of innovation.

Several endogenous institutions were identified that act as barriers to the diffusion of innovation throughout an organisation. Attempts to re‐design and negate these barriers were also identified.

Institutional analysis of innovation has a tendency to be limited to formal and exogenous institutions. The paper underscores the importance of taking into account the endogenous institutional set‐up. The results are drawn on a single case study.

The understanding of public procurement of innovation needs to be expanded beyond the formal procurement process. Special attention needs to be given to diffusion processes where institutional coordination and re‐design should be considered an important component.

The paper considers diffusion as an important component of public procurement of innovation, and emphasises the importance of the endogenous institutional level both for understanding and for coordinating diffusion, which are two aspects commonly neglected in the literature.

This paper aims to present a shape sensing method and feedback control strategy based on fiber Bragg grating (FBG) sensor to improve the control accuracy of the robot and ensure the safety of the cardiac interventional surgery.

To theoretically describe the shape of the catheter robot, the kinematic model is established by the geometric analysis method. And to obtain the actual shape, a large curvature assemble sensor based on FBG is adopted and a novel simple shape reconstruction model is proposed, which can provide the shape curve and distal position. In addition, the influence of external load on the bending deformation is investigated by experiments. To improve the shape accuracy of the robot, a shape feedback control method is presented to control the catheter robot, which can control the robot to bend into the pre-given desired shape.

Experiment results verify the effectiveness of the shape sensing method and the reconstruction model, and the correlation coefficients of three sets of curve in different coordinate directions are 0.9986, 0.9992 and 0.9999. Results of the shape feedback experiment show that the curvature error and direction angle error are 1.42% and 10.3%, respectively. The continuum catheter robot can be controlled to achieve the desired bending shape.

The shape reconstruction method and feedback control strategy proposed in this paper can improve the control accuracy of the robot to avoid the risk of the collision with the surrounding blood vessels, the tissues and organs.

The purpose of this paper is to describe a numerical inversion technology developed to reconstruct endocardial electric potential maps on the internal surface of heart chambers utilizing intracavitary multi‐electrode catheter measurements. The objective is to perform the reconstruction real time with high accuracy, thereby allowing the incorporation of the technology into medical imaging systems.

Electrode potential points from several beats are merged in order to maximize the information extracted from the catheter measurements. To solve the ill‐posed inverse problem fast, numerically stable solution algorithms based on generalized Tikhonov regularization and bidiagonalization are developed. The latter algorithm also provides an efficient framework for choosing the regularization parameter optimally.

Results of three examples are presented to thoroughly illustrate the performance of the algorithm: one with synthetic data generated in a computational electromagnetics (virtual lab) environment, thereby allowing exact error analysis; another with measured data from a phantom‐bench human heart model where the effect of measurement errors can be investigated in a controlled environment; and a third example that illustrates how the algorithm performs when the catheter data are collected in vivo in a swine heart.

The speed and accuracy in the three examples successfully prove that the inversion technology can be a key component of medical imaging systems.

While some elements of these computational models and techniques presented have been used for decades, the authors achieve speed and accuracy that have not been reported before by combining multi‐beat catheter measurements, the generalized Tikhonov regularization technique, a bidiagonalization algorithm and other top‐notch linear algebra techniques.

The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past couple of decades, the percentage of deaths associated with blood vessel diseases has risen sharply to nearly one third of all fatalities. For vascular disease to be stopped in its tracks, it is essential to understand the vascular geometry and blood flow within the artery. In recent scenarios, because of higher thermal properties and the ability to move across stenosis and tumor cells, nanoparticles are becoming a more common and effective approach in treating cardiovascular diseases and cancer cells.

The present mathematical study investigates the blood flow behavior in the overlapped stenosed curved artery with cylinder shape catheter. The induced magnetic field and entropy generation for blood flow in the presence of a heat source, magnetic field and nanoparticle (Fe₃O₄) have been analyzed numerically. Blood is considered in artery as two-phases: core and plasma region. Power-law fluid has been considered for core region fluid, whereas Newtonian fluid is considered in the plasma region. Strongly implicit Stone’s method has been considered to solve the system of nonlinear partial differential equations (PDE’s) with 10–6 tolerance error.

The influence of various parameters has been discussed graphically. This study concludes that arterial curvature increases the probability of atherosclerosis deposition, while using an external heating source flow temperature and entropy production. In addition, if the thermal treatment procedure is carried out inside a magnetic field, it will aid in controlling blood flow velocity.

The findings of this computational analysis hold great significance for clinical researchers and biologists, as they offer the ability to anticipate the occurrence of endothelial cell injury and plaque accumulation in curved arteries with specific wall shear stress patterns. Consequently, these insights may contribute to the potential alleviation of the severity of these illnesses. Furthermore, the application of nanoparticles and external heat sources in the discipline of blood circulation has potential in the medically healing of illness conditions such as stenosis, cancer cells and muscular discomfort through the usage of beneficial effects.

Catheter related blood stream infection (CRBSI) remains an important complication of central venous catheters(CVCs). Educational programmes have been associated with CRBSI reduction but evidence in total parenteral nutrition (TPN) patients is limited, despite an increased risk of CRBSI. The effect of educational processes were evaluated and the value of different methods of expression of CRBSI incidence were assessed.

Study was performed in a 525‐bed tertiary university hospital over 12 years. A multidisciplinary TPN committee was created to examine CRBSI episodes and a parallel education programme was set up and maintained. Prospectively collected data were analysed from 1,392 patients in whom 2,565 CVCs were used over 15,397 CVC days. CRBSI incidence was expressed as CRBSI episodes per 1,000 CVC days, percentage patients or percentage CVCs infected.

CRBSI incidence fell from 33 to 7 episodes per 1,000 CVC days (p<0.01). Percentage of infected CVCs fell from 17 per cent to 5 per cent(p <0.05) and proportion of patients affected fell from 27 per cent to 7 per cent(p <0.01). The corresponding slopes of the lines expressing fall in CRBSI rate were −1.3‐0.63 and −1.4 respectively.

A sustained educational programme was associated with a significant fall in CRBSI in TPN patients. An incidence of 5‐7 episodes per 1,000 CVC days, a figure comparable with non‐TPN CVCs, was achievable.

Each method of expression of CRBSI incidence proved valid in this setting and contributed to the educational programme.

The value of this study is that it demonstrates how implementing and sustaining an education programme can achieve reduced rates of infection. No published study utilising all methods of expressing CRBSI incidence could be found.

Recently, the porous media theory has been successively proposed for many bioengineering applications. The purpose of this paper is to analyze if the porous media theory can be applied to model radiofrequency (RF) cardiac ablation.

Blood flow, catheter and tissue are modeled. The latter is further divided into a fluid and a solid phase, and porous media equations are used to model them. The heat source term is modeled using the Laplace equation, and the finite element method is used to solve the governing equations under the appropriate boundary conditions and closure coefficients.

After validation with available literature data, results are shown for different velocities and applied voltages to understand how these parameters affect temperature fields (and necrotic regions).

The model might require further validation with experiments under different conditions after comparisons with available literature. However, this might not be possible due to the experimental complexity.

The improvement in predictions from the model might help the final user, i.e. the surgeon, who uses cardiac ablation to treat arrhythmia.

This is the first time that the porous media theory is applied to RF cardiac ablation. The robustness of the model, in which many variables are taken into account, makes it suitable to better predict temperature fields, and damaged regions, during RF cardiac ablation treatments.

Bruno Latour, one of the architects of actor-network theory, has now enfolded this approach within a larger project, An Inquiry into Modes of Existence – AIME. Framed as an empirical inquiry into the ontological and epistemological conditions of modernity, Latour argues for a radical shift in how “objective truth,” “scientific fact,” and “meaning” are established within the world. In this chapter, I draw on several elements of AIME to illustrate how Latour’s ontology, building on, augmenting and responding to criticisms of actor-network theory, can be used to explore higher education, focussing on one episode derived from a larger ethnography of medical education.