James Bryan Williams

A numerical study of blood flow in coronary artery bypass graft side-to-side anastomoses.

AbstractPurpose: When sequential grafts are used in multivessel coronary artery bypass grafting, the graft first supplies blood to one or more coronary arteries via a side-to-side anastomosis. We studied hemodynamics in idealized models of “parallel” and “diamond” side-to-side anastomoses, identifying features that might promote restenosis. Methods: Blood flow was computed in three representative anastomosis configurations: parallel side-to-side, diamond side-to-side, and end-to-side. We compared configurations and the effect of host-graft diameter ratio. Results:Hemodynamic patterns depended strongly on anastomosis geometry and graft/host diameter ratio. In the distal graft, the diamond configuration had large areas of low wall shear stress (WSS) and high spatial WSS gradients. In the proximal graft the unfavorable WSS patterns were comparable for all models, while the distal portion of the host artery the diamond model was best. Models with smaller host arteries had smaller regions of low WSS. Conclusions: The parallel configuration was preferred over the diamond for maintaining graft patency, while the diamond configuration appeared best for maintaining host artery patency. Since graft patency is critical, parallel configurations seem hemodynamically advantageous. Larger graft/host ratios have better hemodynamic performance than smaller ones.

Data Safe Havens in health research and healthcare.

Motivation: The data that put the ‘evidence’ into ‘evidence-based medicine’ are central to developments in public health, primary and hospital care. A fundamental challenge is to site such data in repositories that can easily be accessed under appropriate technical and governance controls which are effectively audited and are viewed as trustworthy by diverse stakeholders. This demands socio-technical solutions that may easily become enmeshed in protracted debate and controversy as they encounter the norms, values, expectations and concerns of diverse stakeholders. In this context, the development of what are called ‘Data Safe Havens’ has been crucial. Unfortunately, the origins and evolution of the term have led to a range of different definitions being assumed by different groups. There is, however, an intuitively meaningful interpretation that is often assumed by those who have not previously encountered the term: a repository in which useful but potentially sensitive data may be kept securely under governance and informatics systems that are fit-for-purpose and appropriately tailored to the nature of the data being maintained, and may be accessed and utilized by legitimate users undertaking work and research contributing to biomedicine, health and/or to ongoing development of healthcare systems. Results: This review explores a fundamental question: ‘what are the specific criteria that ought reasonably to be met by a data repository if it is to be seen as consistent with this interpretation and viewed as worthy of being accorded the status of ‘Data Safe Haven’ by key stakeholders’? We propose 12 such criteria. Contact: paul.burton@bristol.ac.uk

Software engineering in health care: is it really different? and how to gain impact

Over the last several years, software engineering (SE) has given birth to several communities and venues related to research on SE in the context of health care systems. By and large, the interest in this topic has been spurred by alarming failures of software-intensive systems that have been deployed to address some of the challenges faced in current health care environments. Today, the software engineering in health care (SERC) community faces several challenges. It needs to justify the significance of its existence towards the general SE community and towards the medical/health informatics community. The purpose of this paper is to explore some of the fundamental challenges pertaining to SERC, to consider whether these challenges require a dedicated community-based effort and to generate recommendations on how to strengthen its impact. We argue that the community should adopt a conceptual model of knowledge translation (KT) analogous those used in the medical domain to position its research and maximize its impact.

Social networks for health care: Addressing regulatory gaps with privacy-by-design

Social computing is a relatively new approach to systems design that emphasizes the importance of facilitating collaboration and communication between users. Although social networking is now part of mainstream culture, the use of these applications in the health care space is still in its infancy in Canada. As major vendors are preparing to enter the marketplace, it is important for a wide variety of stakeholders to discern the ramifications of this next wave of technological innovation. This paper discusses social networking applications for health care, and the challenges of dealing with this new type of information management system under current Canadian law. While regulatory authorities have considered the privacy and security implications of social networking in the course of investigating complaints, this paper contains the first explicit analysis of the legal difficulties surrounding the use of social networking for health care applications in Canada. Those risks not covered by the current regulatory framework are assessed from the standpoint of privacy-by-design, as we discuss how software developers can build privacy protection into social networking applications.

The smart internet as a catalyst for health care reform

Health care systems around the world are under pressure to lower costs and improve outcomes. Over the last decade, the Internet has begun to impact the traditional consumer-provider relationship in the health care sector. Patients are now commonly known to search the Internet for information and services relevant to their condition in addition to consulting with their providers. The Smart Internet has been envisioned as a major step in evolving the Internet into a more user-centric, pro-active and intelligent medium. In this chapter, we discuss the opportunities of Smart Internet technologies in context of health care applications. We characterize the current state of Internet-based health applications and summarize important challenges to be addressed in order to be able to use the Smart Internet for reforming health care systems.