Background: Abdominal wall hernia is a common surgical condition. Patients may present in an emergency with bowel obstruction, incarceration or strangulation. Small bowel obstruction (SBO) is a serious surgical condition associated with significant morbidity. The aim of this study was to describe current management and outcomes of patients with obstructed hernia in the UK as identified in the National Audit of Small Bowel Obstruction (NASBO). Methods: NASBO collated data on adults treated for SBO at 131 UK hospitals between January and March 2017. Those with obstruction due to abdominal wall hernia were included in this study. Demographics, co-morbidity, imaging, operative treatment, and in-hospital outcomes were recorded. Modelling for factors associated with mortality and complications was undertaken using Cox proportional hazards and multivariable regression modelling. Results: NASBO included 2341 patients, of whom 415 (17⋅7 per cent) had SBO due to hernia. Surgery was performed in 312 (75⋅2 per cent) of the 415 patients; small bowel resection was required in 198 (63⋅5 per cent) of these operations. Non-operative management was reported in 35 (54 per cent) of 65 patients with a parastomal hernia and in 34 (32⋅1 per cent) of 106 patients with an incisional hernia. The in-hospital mortality rate was 9⋅4 per cent (39 of 415), and was highest in patients with a groin hernia (11⋅1 per cent, 17 of 153). Complications were common, including lower respiratory tract infection in 16⋅3 per cent of patients with a groin hernia. Increased age was associated with an increased risk of death (hazard ratio 1⋅05, 95 per cent c.i. 1⋅01 to 1⋅10; P = 0⋅009) and complications (odds ratio 1⋅05, 95 per cent c.i. 1⋅02 to 1⋅09; P = 0⋅001). Conclusion: NASBO has highlighted poor outcomes for patients with SBO due to hernia, highlighting the need for quality improvement initiatives in this group. *Members of the National Audit of Small Bowel Obstruction (NASBO) Steering Group and NASBO Collaborators are co-authors of this study and are listed in Appendix S1 (supporting information) Funding information

Background The peak oxygen uptake (VO2peak) is considered the most reliable parameter for evaluating cardiorespiratory fitness and guiding physical training. However, not everyone has access to VO2peak measurements. As a more accessible alternative, heart rate (HR) variables have emerged. Aim To explore the correlation between HR responses during rest, exercise, recovery, and VO2peak. Methods Thirteen healthy men participated in the study. Resting HR variability and parameters were recorded for 10 minutes using a heart rate monitor while participants were seated. A maximal intermittent treadmill test was conducted to determine the maximum rate of HR increase (rHRI) and obtain VO2peak data (33.53 ± 8.22 mL/kg/min). The test speed was set based on the International Physical Activity Questionnaire (IPAQ) classification: 8 km/h for inactive or insufficiently active individuals, and 10 km/h for active and highly active individuals. Additionally, HR recovery (HRR) was measured during a 10-minute seated recovery period. Results Significant correlations were observed between resting HR (r = -0.78, p = 0.001), average RR interval (iRR) (r = 0.73, p = 0.004), percentage of iRR differences exceeding 50 ms (pNN50) (r = 0.64, p = 0.001), HR (r = -0.60, p = 0.003), and VO2peak. However, no significant correlation was found between rHRI and VO2peak (r = 0.38, p = 0.2). Conclusion Resting HR parameters, HR variability, and HRR showed significant associations with VO2peak. These HR variables can be useful alternatives for assessing and prescribing physical training when direct measurement of VO2peak is not feasible.

Introduction The pathogenesis of Chronic Chagas Cardiomyopathy (CCC) is not yet fully elucidated. However, dysautonomia is one of the factors involved, in addition to being the essential mechanism in the pathogenesis of the Digestive Form of Chagas Disease (DFCD). The prognostic value of dysautonomia remains speculative, and there are no correlative studies of dysautonomia in CCC and DFCD. Purpose This study has three aims: a) to investigate in patients with CCC the relationship between cardiac dysautonomia, indirectly studied by heart rate variability (HRV), and the prognostic stratification assessed by the Rassi score; b) to compare the HRV in groups with isolated CCC and with the mixed form, i.e. CCC associated with DFCD; c) to evaluate the power of combining HRV indices to predict the risk class of each patient, using machine learning. Methods Thirty-one patients with CCC were classified into three risk groups (low, intermediate and high) according to their Rassi score and had two electrocardiograms (ECG) recorded, i.e. the conventional 12-lead and a single lead, the latter for a period of 10 to 20 minutes. From the single lead ECG, two equally sized RR series were generated and 31 HRV indices were calculated from each. The HRV was then compared between the three risk groups and also regarding the presence or not of concomitant digestive impairment. Taking HRV indices as inputs, four machine learning models were compared in its ability to predict the risk class of each patient. A previous step of attribute selection (sequential feature selection) was applied to identify the most relevant HRV indices for each algorithm. Results Comparing the HRV indices in the three risk groups obtained with the Rassi score, the phase entropy is decreased [0.91 (0.90, 0.91) vs 0.87 (0.86, 0.89); p=0.039] and the percentage of inflection points is increased [66.4 (63.5, 71.2) vs 58.2 (53.4, 63.3); p=0.032] in patients in the high-risk group, compared to the low-risk group. Of the 31 patients with CCC, 14 had the mixed form of the disease, i.e. with associated digestive impairment. In the latter, the triangular interpolation of the RR interval histogram decreased significantly [78.1 (62.5, 101.6) vs 121.1 (80.1, 146.5), p=0.046], while the absolute power in the low-frequency band decreased with strong trend to statistical significance [28.5 (17.1, 97.5) vs 86.9 (44.1, 171.7), p=0.06]. The best predictive model for each risk group was obtained with the Support Vector Machine, reaching an overall F1-score of 0.61. Conclusions The worst prognosis, indicated by the Rassi score, is associated with increased heart rate fragmentation. The combination of HRV indices enhanced the accuracy of the risk stratification. Compared to CCC the mixed form of Chagas' disease displays a decrease in the components of slow heart rate oscillation, suggesting a higher degree of sympathetic autonomic denervation associated with parasympathetic impairment. FUNDunding Acknowledgement Type of funding sources: Foundation. Main funding source(s): São Paulo Research Foundation (FAPESP)

Introduction: Cortical spreading depression (CSD) is an electrophysiological phenomenon used experimentally to analyze the direct modulation of the electrical activity of cortical neurons, and the dissemination of this wave may be associated with several pathological factors. Hyperprolactinemia is a pathological condition related to high plasma levels of prolactin, which, at normal levels, influences brain functions. However, high levels of this hormone can act differently in the cerebral cortex. Melatonin is an influential hormone in the central and peripheral nervous system, playing a cerebrovascular, neuroendocrine, neuroimmune and neuroprotector regulatory role. Objectives: The objective was to analyze CSD in rats induced to hyperprolactinemia and treated with melatonin. Results: 64 rats were used, which were divided into two treatment periods (30 and 60 days), subdivided into 4 groups each: Control, Vehicle, Hiper (rats induced to hyperprolactinemia) and Hiper+mel (rats induced to hyperprolactinemia and treated with melatonin). After treatment, the animals were anesthetized for analysis of the CSD propagation velocity, which was calculated based on the distance between the two recording electrodes, and the time spent by the CSD to cover this distance. The recording was performed at the two parietal points of the right cerebral hemisphere, for a continuous period of 4 hours. The ANOVA results of the animals treated for 30 days showed that the control group had an average speed of 3.43 ± 0.11 mm/min and the vehicle 3.10 ± 0.04 mm/min. In the Hyper group, the mean speed was 3.38 ± 0.16 mm/min, while the Hyper+mel group had a speed of 2.21 ± 0.02 mm/min. As for the animals treated for 60 days, the control group obtained a speed of 3.21 ± 0.22 mm/min, while the vehicle 3.06 ± 0.17 mm/min. The hyper group 4.65 ± 0.16 mm/min and the hyper+mel 2.34 ± 0.19 mm/min. There was a significant increase in the hyper group compared to the others, and a significant decrease in the hyper+mel group compared to the other groups. Conclusions:It is concluded that hyperprolactinemia has a direct effect on increasing the speed of CSD, on the other hand, the neuroprotective effects of melatonin were sufficient to establish efficiency against hyperprolactinemia.