Anaesthesia in patients with liver disease.

PURPOSE OF REVIEW: The purpose of this review is to summarize the most recent up to date research data and recommendations regarding anaesthetic management of patients with liver disease undergoing surgery. The incidence of chronic liver disease (CLD) continues to rise and perioperative mortality and morbidity remains unacceptably high in this group. Meticulous preoperative assessment and carefully planned anaesthetic management are vital in improving outcomes in patients with liver disease undergoing surgery. RECENT FINDINGS: The presence of cirrhosis is associated with a significantly increased risk of postoperative morbidity and mortality in patients undergoing elective surgery. The Child--Pugh--Turcotte scale and model for end-stage liver disease (MELD) score remain the most commonly applied scoring systems in preoperative risk assessment, but new MELD-based indices and novel scoring systems might offer better prognostic value. Propofol and new inhalational agents (sevoflurane, desflurane) are recommended hypnotic agents. The titration of opiates in the perioperative period is recommended because of their altered metabolism in patients with liver disease. Perioperative management should include close haemodynamic monitoring and admission to a critical care area should be considered. SUMMARY: Patients with liver disease undergoing anaesthesia pose significant challenges and advanced planning and preparation are required in order to improve perioperative outcomes in this group. VIDEO ABSTRACT: http://links.lww.com/COAN/A43.

Stochastic transparency.

Stochastic transparency provides a unified approach to order-independent transparency, antialiasing, and deep shadow maps. It augments screen-door transparency using a random sub-pixel stipple pattern, where each fragment of transparent geometry covers a random subset of pixel samples of size proportional to alpha. This results in correct alpha-blended colors on average, in a single render pass with fixed memory size and no sorting, but introduces noise. We reduce this noise by an alpha correction pass, and by an accumulation pass that uses a stochastic shadow map from the camera. At the pixel level, the algorithm does not branch and contains no read-modify-write loops, other than traditional z-buffer blend operations. This makes it an excellent match for modern massively parallel GPU hardware. Stochastic transparency is very simple to implement and supports all types of transparent geometry, able without coding for special cases to mix hair, smoke, foliage, windows, and transparent cloth in a single scene.

oRGB: a practical opponent color space for computer graphics.

Designed for computer graphics, oRGB is a new color model based on opponent color theory. It works well for both HSV-style color selection and computational applications such as color transfer. oRGB also enables new applications such as a quantitative cool-to-warm metric, intuitive color manipulation and variations, and simple gamut mapping.

Clinical review: the role of the intensive care physician in mass casualty incidents: planning, organisation, and leadership.

There is a long-standing, broad assumption that hospitals will ably receive and efficiently provide comprehensive care to victims following a mass casualty event. Unfortunately, the majority of medical major incident plans are insufficiently focused on strategies and procedures that extend beyond the pre-hospital and early-hospital phases of care. Recent events underscore two important lessons: (a) the role of intensive care specialists extends well beyond the intensive care unit during such events, and (b) non-intensive care hospital personnel must have the ability to provide basic critical care. The bombing of the London transport network, while highlighting some good practices in our major incident planning, also exposed weaknesses already described by others. Whilst this paper uses the events of the 7 July 2005 as its point of reference, the lessons learned and the changes incorporated in our planning have generic applications to mass casualty events. In the UK, the Department of Health convened an expert symposium in June 2007 to identify lessons learned from 7 July 2005 and disseminate them for the benefit of the wider medical community. The experiences of clinicians from critical care units in London made a large contribution to this process and are discussed in this paper.

Reduction in critical mortality in urban mass casualty incidents: analysis of triage, surge, and resource use after the London bombings on July 7, 2005.

BACKGROUND: The terrorist bombings in London on July 7, 2005, produced the largest mass casualty event in the UK since World War 2. The aim of this study was to analyse the prehospital and in-hospital response to the incident and identify system processes that optimise resource use and reduce critical mortality. METHODS: This study was a retrospective analysis of the London-wide prehospital response and the in-hospital response of one academic trauma centre. Data for injuries, outcome, triage, patient flow, and resource use were obtained by the review of emergency services and hospital records. FINDINGS: There were 775 casualties and 56 deaths, 53 at scene. 55 patients were triaged to priority dispatch and 20 patients were critically injured. Critical mortality was low at 15% and not due to poor availability of resources. Over-triage rates were reduced where advanced prehospital teams did initial scene triage. The Royal London Hospital received 194 casualties, 27 arrived as seriously injured. Maximum surge rate was 18 seriously injured patients per hour and resuscitation room capacity was reached within 15 min. 17 patients needed surgery and 264 units of blood products were used in the first 15 h, close to the hospital's routine daily blood use. INTERPRETATION: Critical mortality was reduced by rapid advanced major incident management and seems unrelated to over-triage. Hospital surge capacity can be maintained by repeated effective triage and implementing a hospital-wide damage control philosophy, keeping investigations to a minimum, and transferring patients rapidly to definitive care.

Interactive display of isosurfaces with global illumination.

In many applications, volumetric data sets are examined by displaying isosurfaces, surfaces where the data, or some function of the data, takes on a given value. Interactive applications typically use local lighting models to render such surfaces. This work introduces a method to precompute or lazily compute global illumination to improve interactive isosurface renderings. The precomputed illumination resides in a separate volume and includes direct light, shadows, and interreflections. Using this volume, interactive globally illuminated renderings of isosurfaces become feasible while still allowing dynamic manipulation of lighting, viewpoint and isovalue.