Nearly 40 000 people in the UK and many more worldwide have cardiac surgery annually. Adverse neurological outcomes post-cardiac surgery have been well recognized for many years and are an important cause of postoperative morbidity and mortality. They have been classified by The American College of Cardiology and the American Heart Association into Types 1 and 2. 1 Type 1 neurological injury is attributable to brain death, non-fatal stroke, and new transient ischaemic attack, whereas delirium and postoperative cognitive dysfunction (POCD) are classified as Type 2 neurological injuries. The two most significant clinical neurological abnormalities after cardiac surgery are stroke and POCD. The reported incidence of stroke in patients undergoing isolated coronary artery bypass graft (CABG) is 1.6%. 2 However, quantifying the incidence of POCD is more complex. In this review, we will solely focus on the relationship between POCD and cardiac surgery.

We investigate the design of an entire mobile imaging system for early detection of melanoma. Different from previous work, we focus on smartphone-captured visible light images. Our design addresses two major challenges. First, images acquired using a smartphone under loosely-controlled environmental conditions may be subject to various distortions, and this makes melanoma detection more difficult. Second, processing performed on a smartphone is subject to stringent computation and memory constraints. In our work, we propose a detection system that is optimized to run entirely on the resourceconstrained smartphone. Our system intends to localize the skin lesion by combining a lightweight method for skin detection with a hierarchical segmentation approach using two fast segmentation methods. Moreover, we study an extensive set of image features and propose new numerical features to characterize a skin lesion. Furthermore, we propose an improved feature selection algorithm to determine a small set of discriminative features used by the final lightweight system. In addition, we study the human-computer interface (HCI) design to understand the usability and acceptance issues of the proposed system. Our extensive evaluation on an image dataset provided by National Skin Center -Singapore (117 benign nevi and 67 malignant melanoma) confirms the effectiveness of the proposed system for melanoma detection: 89.09% sensitivity at specificity ≥ 90%.

High-risk surgery represents 12.5% of cases but contributes 80% of deaths in the elderly population. Reduction in morbidity and mortality by the use of intervention strategies could result in thousands of lives being saved and savings of up to £400m per annum in the UK. This has resulted in the drive towards goal-directed therapy and intraoperative flow optimization of high-risk surgical patients being advocated by authorities such as the National Institute of Health and Care Excellence and the Association of Anaesthetists of Great Britain and Ireland.Conventional intraoperative monitoring gives little insight into the profound physiological changes occurring as a result of anesthesia and surgery. The build-up of an oxygen debt is associated with a poor outcome and strategies have been developed in the postoperative period to improve outcomes by repayment of this debt. New monitoring technologies such as minimally invasive cardiac output, depth of anesthesia and cerebral oximetry can minimize oxygen debt build-up. This has the potential to reduce complications and lessen the need for postoperative optimization in high-dependency areas.Flow monitoring has thus emerged as essential during intraoperative monitoring in high-risk surgery. However, evidence suggests that current optimization strategies of deliberately increasing flow to meet predefined targets may not reduce mortality.Could the addition of depth of anesthesia and cerebral and tissue oximetry monitoring produce a further improvement in outcomes?Retrospective studies indicate a combination of excessive depth of anesthesia hypotension and low anesthesia requirement results in increased mortality and length of hospital stay.Near infrared technology allows assessment and maintenance of cerebral and tissue oxygenation, a strategy, which has been associated with improved outcomes. The suggestion that the brain is an index organ for tissue oxygenation, especially in the elderly, indicates a role for this technology in the intraoperative period to assess the adequacy of oxygen delivery and reduce the build-up of an oxygen debt.The aim of this article is to make the case for depth of anesthesia and cerebral oximetry alongside flow monitoring as a strategy for reducing oxygen debt during high-risk surgery and further improve outcomes in high-risk surgical patients.

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SummaryExcessive neck flexion and rotation in certain surgical positions may cause kinking of the internal jugular vein that obstructs cerebral venous blood flow and results in elevated intracranial pressure. The objective of this study was to measure internal jugular vein flow and identify potential impediments to venous flow in supine, prone, and park bench positions using non-anaesthetised volunteers. Twenty-seven volunteers were recruited. Venous flow rate was derived from ultrasound measurements of the vessel cross-sectional area and flow velocity. Change from supine to prone position produced a significant increase in both jugular vein cross-sectional areas without affecting venous flows. In the right park bench position, the right internal jugular vein cross-sectional area decreased from 1.2 to 0.9 cm 2 (p = 0.027) without substantive changes in mean venous flow rate (p = 0.91) when compared with supine.