Among adults undergoing noncardiac surgery, MINS is common and associated with substantial mortality.

ObjectiveTo assess whether a faecal immunochemical test (FIT) could be used to select patients with suspected colorectal cancer (CRC) symptoms for urgent investigation.DesignMulticentre, double-blinded diagnostic accuracy study in 50 National Health Service (NHS) hospitals across England between October 2017 and December 2019. Patients referred to secondary care with suspected CRC symptoms meeting NHS England criteria for urgent 2 weeks wait referral and triaged to investigation with colonoscopy were invited to perform a quantitative FIT. The sensitivity of FIT for CRC, and effect of relevant variables on its diagnostic accuracy was assessed.Results9822 patients were included in the final analysis. The prevalence of CRC at colonoscopy was 3.3%. The FIT positivity decreased from 37.2% to 19.0% and 7.6%, respectively, at cut-offs of 2, 10 and 150 µg haemoglobin/g faeces (µg/g). The positive predictive values of FIT for CRC at these cut-offs were 8.7% (95% CI, 7.8% to 9.7%), 16.1% (95% CI 14.4% to 17.8%) and 31.1% (95% CI 27.8% to 34.6%), respectively, and the negative predictive values were 99.8% (95% CI 99.7% to 99.9%), 99.6% (95% CI 99.5% to 99.7%) and 98.9% (95% CI 98.7% to 99.1%), respectively. The sensitivity of FIT for CRC decreased at the same cut-offs from 97.0% (95% CI 94.5% to 98.5%) to 90.9% (95% CI 87.2% to 93.8%) and 70.8% (95% CI 65.6% to 75.7%), respectively, while the specificity increased from 64.9% (95% CI 63.9% to 65.8%) to 83.5% (95% CI 82.8% to 84.3%) and 94.6% (95% CI 94.1% to 95.0%), respectively. The area under the receiver operating characteristic curve was 0.93 (95% CI 0.92 to 0.95).ConclusionFIT sensitivity is maximised to 97.0% at the lowest cut-off (2 µg/g); a negative FIT result at this cut-off can effectively rule out CRC and a positive FIT result is better than symptoms to select patients for urgent investigations.Trial registration numberISRCTN49676259.

Faecal immunochemical testing (FIT) has a high sensitivity for the detection of colorectal cancer (CRC). In a symptomatic population FIT may identify those patients who require colorectal investigation with the highest priority. FIT offers considerable advantages over the use of symptoms alone, as an objective measure of risk with a vastly superior positive predictive value for CRC, while conversely identifying a truly low risk cohort of patients. The aim of this guideline was to provide a clear strategy for the use of FIT in the diagnostic pathway of people with signs or symptoms of a suspected diagnosis of CRC. The guideline was jointly developed by the Association of Coloproctology of Great Britain and Ireland/British Society of Gastroenterology, specifically by a 21-member multidisciplinary guideline development group (GDG). A systematic review of 13 535 publications was undertaken to develop 23 evidence and expert opinion-based recommendations for the triage of people with symptoms of a suspected CRC diagnosis in primary care. In order to achieve consensus among a broad group of key stakeholders, we completed an extended Delphi of the GDG, and also 61 other individuals across the UK and Ireland, including by members of the public, charities and primary and secondary care. Seventeen research recommendations were also prioritised to inform clinical management.

Faecal immunochemical tests for haemoglobin (FIT) are widely used in asymptomatic population screening for colorectal (bowel) cancer. FIT are also used to assist with the assessment of patients presenting with lower abdominal symptoms. Quantitative FIT allow the generation of numerical estimates of faecal haemoglobin (f-Hb) concentrations. There is now great interest in "low" f-Hb concentrations in these clinical settings: in consequence, knowledge of the detection capability is very important for f-Hb concentration examinations. There are a number of current problems associated with the reporting of low f-Hb concentrations and wide misunderstanding of the metrological aspects of examinations of f-Hb at low concentrations. These would be solved if the detectability characteristics of f-Hb concentration examinations, namely, the limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ), were generated, validated and used in reporting systems exactly as recommended in the EP17-A2 guideline of the Clinical Laboratory Standards Institute. LoB and LoD are statistical concepts, but the LoQ depends on definition of analytical performance specifications (APS). In this Opinion Paper proposals for interim APS are made, based on the current state of the art achieved with examinations of faecal samples. It is proposed that LoQ is determined at an examination imprecision of CV≤10% using faecal samples naturally positive for Hb rather than faeces spiked with haemolysate. Detailed proposals for reporting f-Hb data at low concentrations are also made.

Background:The NHS Bowel Cancer Screening Programme (BCSP) in England does not involve general practitioners (GPs). Uptake is ∼58%. The Practice Endorsed Additional Reminder Letter (PEARL) study piloted a GP-endorsed reminder letter.Methods:General practices in Wessex with uptake <55% (prevalent invitations) were invited to participate. Subjects who had been invited for screening, sent a standard 28-day BCSP reminder letter but had not returned a test kit within 30 days of the standard reminder were sent a second reminder letter bearing the GP’s letterhead and signature. Uptake was compared between PEARL and non-PEARL practices by standardised uptake ratio (standardised for prior prevalent uptake and other confounders). In addition, 25 non-PEARL practices were matched with PEARL practices for prior prevalent uptake and number of invitees.Results:Twenty-five practices agreed to participate. A total of 3149 GP-endorsed reminders were sent. Uptake in the PEARL practices was 54% compared with 51% in the matched-control practices. The adjusted RR for uptake was 1.08 (95% CI: 1.05, 1.11, P<0.001) for all invitees and 2.18 (1.79, 2.66, P<0.001) for invitees who had not returned a kit following the standard reminder.Conclusions:The GP-endorsed reminder was associated with significantly increased uptake among subjects not responding to the standard reminder letter.

SUMMARYUnder normal viewing conditions we are little conscious of blur in moving objects, despite the persistence of vision. Moving objects look more blurred in brief than in long exposures, suggesting an active mechanism for suppressing motion blur. To see whether blur suppression would improve visual discrimination of objects, we measured blur discrimination thresholds for moving Gaussian-blurred edges and bars. The observer's task was to decide which of two moving stimuli, presented successively, was the more blurred. It is known that for stationary objects the just-noticeable difference in blur increases with baseline blur ; therefore, if motion increases blur, it would be expected to increase the just-noticeable difference in blur. An active deblurring mechanism, on the other hand, would be expected to counteract the detrimental effects of motion blur on discrimination performance. We found, however, that motion increased thresholds for blur discrimination, both for brief (40 ms) and for longer (150 ms) exposures. We conclude that motion deblurring is a subjective effect, which does not enhance visual discrimination performance. Moving objects appear sharp, not because of some special mechanism that removes blur, but because the visual system is unable to perform the discrimination necessary to decide whether the moving object is really sharp or not.

Objectives: The objective was to determine the incidence of subarachnoid hemorrhage (SAH) diagnosed by lumbar puncture (LP) when the head computed tomography (CT) was reported as demonstrating no subarachnoid blood.Methods: Data were obtained on patients who received LP to diagnose or exclude SAH attending six hospitals over 5 years. Subsequent investigations and outcomes were reviewed in all patients with LPs that did not exclude SAH.Results: A total of 2,248 patients were included. A total of 1,898 LPs were suitable for biochemical analysis, of which 92 (4.8%) were positive for blood, suggesting SAH; 1,507 (79.4%) were negative; and 299 (15.6%) were inconclusive. Of the 92 patients with positive cerebrospinal fluid analysis, eight patients (0.4%) had aneurysms on further imaging, and one had a carotid cavernous fistula. Conclusions:In patients presenting to the emergency department with acute severe headache, LP to diagnose or exclude SAH after negative head CT has a very low diagnostic yield, due to low prevalence of the disease and uninterpretable or inconclusive samples. A clinical decision rule may improve diagnostic yield by selecting patients requiring further evaluation with LP following nondiagnostic or normal noncontrast CT brain imaging.ACADEMIC EMERGENCY MEDICINE 2015;22:1267-1273© 2015 by the Society for Academic Emergency Medicine A cute headache is a common presentation to the emergency department (ED), accounting for around 1% to 2% of all encounters.1,2 The differential diagnosis is wide and includes potentially life-threatening conditions, such as aneurysmal subarachnoid hemorrhage (SAH). Aneurysmal SAH has an incidence of approximately six to eight per 100,000 per person-years, and prevalence of 0.4% to 6%, estimated overall to be around 2%. 3,4 There is an overall risk of rupture of 1.9%.4 SAH has a 1-month mortality of around 40% to 45%, and of those surviving the hemorrhage, around 30% will have severe disabilities. 5,6 Following the initial presentation, the risk of rebleeding is approximately 1.5% per day and 15% to 20% in the first

We identified runners with troponin levels that, in other circumstances, would raise concern for myocardial necrosis. However absence of adverse clinical sequelae would suggest this rise is physiological. The cause and clinical significance of the increased HSTnT levels seen in those that collapsed is yet to be fully elucidated.