BackgroundThere is currently conflicting evidence surrounding the effects of obesity on postoperative outcomes. Previous studies have found obesity to be associated with adverse events, but others have found no association. The aim of this study was to determine whether increasing body mass index (BMI) is an independent risk factor for development of major postoperative complications.MethodsThis was a multicentre prospective cohort study across the UK and Republic of Ireland. Consecutive patients undergoing elective or emergency gastrointestinal surgery over a 4‐month interval (October–December 2014) were eligible for inclusion. The primary outcome was the 30‐day major complication rate (Clavien–Dindo grade III–V). BMI was grouped according to the World Health Organization classification. Multilevel logistic regression models were used to adjust for patient, operative and hospital‐level effects, creating odds ratios (ORs) and 95 per cent confidence intervals (c.i.).ResultsOf 7965 patients, 2545 (32·0 per cent) were of normal weight, 2673 (33·6 per cent) were overweight and 2747 (34·5 per cent) were obese. Overall, 4925 (61·8 per cent) underwent elective and 3038 (38·1 per cent) emergency operations. The 30‐day major complication rate was 11·4 per cent (908 of 7965). In adjusted models, a significant interaction was found between BMI and diagnosis, with an association seen between BMI and major complications for patients with malignancy (overweight: OR 1·59, 95 per cent c.i. 1·12 to 2·29, P = 0·008; obese: OR 1·91, 1·31 to 2·83, P = 0·002; compared with normal weight) but not benign disease (overweight: OR 0·89, 0·71 to 1·12, P = 0·329; obese: OR 0·84, 0·66 to 1·06, P = 0·147).ConclusionOverweight and obese patients undergoing surgery for gastrointestinal malignancy are at increased risk of major postoperative complications compared with those of normal weight.

White matter lesions (WML) are common in the ageing brain, often arising in a field effect of diffuse white matter abnormality. Although WML are associated with cerebral small vessel disease (SVD) and Alzheimer's disease (AD), their cause and pathogenesis remain unclear. The current study tested the hypothesis

4Cultech Limited, Christchurch Rd Port Talbot, Neath Port TalbotThere is a growing body of evidence indicating that the gut microbiota communicates with the CNS influencing mood and behaviour (1)(2)(3)(4)(5)(6)(7) and a role for the microbiota in the development of brain plasticity and the subsequent physiological response has been suggested (2) . Furthermore treatment with probiotics has been shown to alter functional task-related brain activity and changes in midbrain connectivity 9 . To date no study has demonstrated cognitive modification in response to probiotic treatment. The aims of the study were i) To examine the mood effects of probiotic supplementation at rest and in response to psychological stressors ii) To examine the effects of probiotic administration on cognitive functioning.In this pilot study, healthy participants (n = 50) were recruited to take part in a double blind, randomised, controlled trial. Participants were randomized to receive either a probiotic preparation comprising two strains of Lactobacillus acidophilus CUL60 (NCIMB 30157) and CUL21 (NCIMB 30156), Bifidobacterium lactis CUL34 (NCIMB 30172) and Bifidobacterium bifidum CUL20 (NCIMB 30153) at a total of 2.5 × 10 10 cfu/capsule or a placebo for 6 weeks. The sample population comprised 18 males and 32 females, mean age 23.22 years (range 19-38, SD 3.846), with a BMI <30. Participants underwent morphometric measurements (height, weight, % total body fat, hip and waist measurement) and completed mood, stress and depression questionnaires (Bond Lader Mood Scales, Stait Trait Anxiety Inventory and NASA Task Load Index). Participants also were required to perform a battery of computerised cognitive test (COMPASS) measuring attention, executive function, working memory and episodic memory.In terms of mood measures, a significant interaction showed that 'trait' anxiety levels decreased in the active probiotic condition whilst increasing in the placebo condition over the course of the 6 week intervention (p = 0.042). A significant interaction was also observed for tasks of attention; 'continuity of attention increased in response to the probiotic treatment and decreased with the placebo group (p = 0.035). No morphometric changes between the two treatment conditions were recorded during the intervention period. The findings of this pilot trial provide a justification for further studies to characterise the potential cognitive and mood enhancing benefits of probiotics in healthy populations.

Background: Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery. Methods: This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and intercentre variation in critical care admission after emergency laparotomy. Results: Of 4529 patients included, 37.8% (n¼1713) underwent planned critical care admissions from theatre. Some 3.1% (n¼86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n¼133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51e19.97) than planned admissions (OR: 2.32, 95% CI: 1.43e3.85). Some 26.7% of patients (n¼1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8e51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n¼10/145) of centres outside the 95% CI. Conclusions: After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.