Risk Factors for Chronic Abdominal Pain After RYGB: Are Patients Adequately Selected Beforehand?

PURPOSE: Chronic abdominal pain after RYGB is a known issue. Identifying the potential patient-related and modifiable risk factors might contribute to diminish the risk for this undesirable outcome. METHODS: A single-center retrospective cohort study with prospective data collection was conducted with inclusion of all patients who underwent RYGB surgery between 2015 and 2021. Data from the NBSR and medical records were used. Patients with chronic abdominal pain were defined when pain lasting or recurring for more than 3 to 6 months. RESULTS: Six hundred sixty-four patients who underwent RYGB surgery were included with a median follow-up of 60.5 months. Forty-nine patients (7.3%) presented with chronic abdominal pain. Postoperative complications (OR 13.376, p = 0.020) and diagnosis of depression (OR 1.971, p = 0.037) were associated with developing abdominal pain. On the other hand, ex-smokers (OR 0.222, p = 0.040) and older age (0.959, p = 0.004) presented as protective factors. CONCLUSION: Postoperative complications and diagnosis of depression are risk factors for chronic pain after RYGB. The role of the bariatric MDT remains crucial to select these patients adequately beforehand.

Quality of life after emergency laparotomy: a systematic review.

BACKGROUND: Emergency laparotomy is a commonly performed surgical procedure that has higher post-operative morbidity and mortality than elective surgery. Previous research has identified that patients valued postoperative quality of life (QoL) more than the risk of mortality when deciding to undergo emergency surgery. Current pre-operative scoring and risk stratification systems for emergency laparotomy do not account for or provide prediction tools for post-operative QoL. This study aims to systematically review previous literature to determine post-operative QoL in patients who undergo emergency laparotomy. METHODS: A literature search was undertaken in Medline, EMBASE and the Cochrane Library to identify studies measuring post-operative QoL in patients who have had emergency laparotomy up to 29th April 2023. Mean QoL scores from the studies included were combined to calculate the average effect of emergency laparotomy on QoL. The primary outcome of the review was postoperative QoL after emergency laparotomy when compared with a comparator group. Secondary outcomes included the quality of included studies. RESULTS: Ten studies in the literature assessing the QoL of patients after emergency laparotomy were identified. Three studies showed that patients had improved QoL and seven showed worse QoL following emergency laparotomy. Length of time for QoL to return to baseline varied ranged from 3 to 12 months post-operatively. Length of hospital stay was identified as an independent risk factor for poorer QoL post-surgery. CONCLUSIONS: Outcome reporting for patients who undergo emergency laparotomy should be expanded further to include QoL. Further work is required to investigate this and elicit factors that can improve QoL post-operatively.

The effects of bariatric surgery on cardiac function: a systematic review and meta-analysis.

INTRODUCTION: Obesity is associated with alterations in cardiac structure and haemodynamics leading to cardiovascular mortality and morbidity. Culminating evidence suggests improvement of cardiac structure and function following bariatric surgery. OBJECTIVE: To evaluate the effect of bariatric surgery on cardiac structure and function in patients before and after bariatric surgery. METHODS: Systematic review and meta-analysis of studies reporting pre- and postoperative cardiac structure and function parameters on cardiac imaging in patients undergoing bariatric surgery. RESULTS: Eighty studies of 3332 patients were included. Bariatric surgery is associated with a statistically significant improvement in cardiac geometry and function including a decrease of 12.2% (95% CI 0.096-0.149; p < 0.001) in left ventricular (LV) mass index, an increase of 0.155 (95% CI 0.106-0.205; p < 0.001) in E/A ratio, a decrease of 2.012 mm (95% CI 1.356-2.699; p < 0.001) in left atrial diameter, a decrease of 1.16 mm (95% CI 0.62-1.69; p < 0.001) in LV diastolic dimension, and an increase of 1.636% (95% CI 0.706-2.566; p < 0.001) in LV ejection fraction after surgery. CONCLUSION: Bariatric surgery led to reverse remodelling and improvement in cardiac geometry and function driven by metabolic and haemodynamic factors.

Defining the Enablers and Barriers to the Implementation of Large-scale, Health Care-Related Mobile Technology: Qualitative Case Study in a Tertiary Hospital Setting.

BACKGROUND: The successful implementation of clinical smartphone apps in hospital settings requires close collaboration with industry partners. A large-scale, hospital-wide implementation of a clinical mobile app for health care professionals developed in partnership with Google Health and academic partners was deployed on a bring-your-own-device basis using mobile device management at our UK academic hospital. As this was the first large-scale implementation of this type of innovation in the UK health system, important insights and lessons learned from the deployment may be useful to other organizations considering implementing similar technology in partnership with commercial companies. OBJECTIVE: The aims of this study are to define the key enablers and barriers and to propose a road map for the implementation of a hospital-wide clinical mobile app developed in collaboration with an industry partner as a data processor and an academic partner for independent evaluation. METHODS: Semistructured interviews were conducted with high-level stakeholders from industry, academia, and health care providers who had instrumental roles in the implementation of the app at our hospital. The interviews explored the participants' views on the enablers and barriers to the implementation process. The interviews were analyzed using a broadly deductive approach to thematic analysis. RESULTS: In total, 14 participants were interviewed. Key enablers identified were the establishment of a steering committee with high-level clinical involvement, well-defined roles and responsibilities between partners, effective communication strategies with end users, safe information governance precautions, and increased patient engagement and transparency. Barriers identified were the lack of dedicated resources for mobile change at our hospital, risk aversion, unclear strategy and regulation, and the implications of bring-your-own-device and mobile device management policies. The key lessons learned from the deployment process were highlighted, and a road map for the implementation of large-scale clinical mobile apps in hospital settings was proposed. CONCLUSIONS: Despite partnering with one of the world's biggest technology companies, the cultural and technological change required for mobile working and implementation in health care was found to be a significant challenge. With an increasing requirement for health care organizations to partner with industry for advanced mobile technologies, the lessons learned from our implementation can influence how other health care organizations undertake a similar mobile change and improve the chances of successful widespread mobile transformation.

Patient Perceptions on Data Sharing and Applying Artificial Intelligence to Health Care Data: Cross-sectional Survey.

BACKGROUND: Considerable research is being conducted as to how artificial intelligence (AI) can be effectively applied to health care. However, for the successful implementation of AI, large amounts of health data are required for training and testing algorithms. As such, there is a need to understand the perspectives and viewpoints of patients regarding the use of their health data in AI research. OBJECTIVE: We surveyed a large sample of patients for identifying current awareness regarding health data research, and for obtaining their opinions and views on data sharing for AI research purposes, and on the use of AI technology on health care data. METHODS: A cross-sectional survey with patients was conducted at a large multisite teaching hospital in the United Kingdom. Data were collected on patient and public views about sharing health data for research and the use of AI on health data. RESULTS: A total of 408 participants completed the survey. The respondents had generally low levels of prior knowledge about AI. Most were comfortable with sharing health data with the National Health Service (NHS) (318/408, 77.9%) or universities (268/408, 65.7%), but far fewer with commercial organizations such as technology companies (108/408, 26.4%). The majority endorsed AI research on health care data (357/408, 87.4%) and health care imaging (353/408, 86.4%) in a university setting, provided that concerns about privacy, reidentification of anonymized health care data, and consent processes were addressed. CONCLUSIONS: There were significant variations in the patient perceptions, levels of support, and understanding of health data research and AI. Greater public engagement levels and debates are necessary to ensure the acceptability of AI research and its successful integration into clinical practice in future.

Developing a reporting guideline for artificial intelligence-centred diagnostic test accuracy studies: the STARD-AI protocol.

INTRODUCTION: Standards for Reporting of Diagnostic Accuracy Study (STARD) was developed to improve the completeness and transparency of reporting in studies investigating diagnostic test accuracy. However, its current form, STARD 2015 does not address the issues and challenges raised by artificial intelligence (AI)-centred interventions. As such, we propose an AI-specific version of the STARD checklist (STARD-AI), which focuses on the reporting of AI diagnostic test accuracy studies. This paper describes the methods that will be used to develop STARD-AI. METHODS AND ANALYSIS: The development of the STARD-AI checklist can be distilled into six stages. (1) A project organisation phase has been undertaken, during which a Project Team and a Steering Committee were established; (2) An item generation process has been completed following a literature review, a patient and public involvement and engagement exercise and an online scoping survey of international experts; (3) A three-round modified Delphi consensus methodology is underway, which will culminate in a teleconference consensus meeting of experts; (4) Thereafter, the Project Team will draft the initial STARD-AI checklist and the accompanying documents; (5) A piloting phase among expert users will be undertaken to identify items which are either unclear or missing. This process, consisting of surveys and semistructured interviews, will contribute towards the explanation and elaboration document and (6) On finalisation of the manuscripts, the group's efforts turn towards an organised dissemination and implementation strategy to maximise end-user adoption. ETHICS AND DISSEMINATION: Ethical approval has been granted by the Joint Research Compliance Office at Imperial College London (reference number: 19IC5679). A dissemination strategy will be aimed towards five groups of stakeholders: (1) academia, (2) policy, (3) guidelines and regulation, (4) industry and (5) public and non-specific stakeholders. We anticipate that dissemination will take place in Q3 of 2021.

Diagnostic accuracy of deep learning in medical imaging: a systematic review and meta-analysis.

Deep learning (DL) has the potential to transform medical diagnostics. However, the diagnostic accuracy of DL is uncertain. Our aim was to evaluate the diagnostic accuracy of DL algorithms to identify pathology in medical imaging. Searches were conducted in Medline and EMBASE up to January 2020. We identified 11,921 studies, of which 503 were included in the systematic review. Eighty-two studies in ophthalmology, 82 in breast disease and 115 in respiratory disease were included for meta-analysis. Two hundred twenty-four studies in other specialities were included for qualitative review. Peer-reviewed studies that reported on the diagnostic accuracy of DL algorithms to identify pathology using medical imaging were included. Primary outcomes were measures of diagnostic accuracy, study design and reporting standards in the literature. Estimates were pooled using random-effects meta-analysis. In ophthalmology, AUC's ranged between 0.933 and 1 for diagnosing diabetic retinopathy, age-related macular degeneration and glaucoma on retinal fundus photographs and optical coherence tomography. In respiratory imaging, AUC's ranged between 0.864 and 0.937 for diagnosing lung nodules or lung cancer on chest X-ray or CT scan. For breast imaging, AUC's ranged between 0.868 and 0.909 for diagnosing breast cancer on mammogram, ultrasound, MRI and digital breast tomosynthesis. Heterogeneity was high between studies and extensive variation in methodology, terminology and outcome measures was noted. This can lead to an overestimation of the diagnostic accuracy of DL algorithms on medical imaging. There is an immediate need for the development of artificial intelligence-specific EQUATOR guidelines, particularly STARD, in order to provide guidance around key issues in this field.

Initial Experience With a New Robotic Surgical System for Cholecystectomy.

Background. Laparoscopic cholecystectomy has been the gold standard treatment for symptomatic cholelithiasis for more than 3 decades. Robotic techniques are gaining traction in surgery, and recently, the Senhance™ robotic system was introduced. The system offers advantages over other robotic systems such as improved ergonomics, haptic feedback, eye tracking, and usability of standard laparoscopic trocars and reusable instruments. The Senhance was evaluated to understand the feasibility, benefits, and drawbacks of its use in cholecystectomy. Study Design. A prospectively maintained database of the first 20 patients undergoing cholecystectomy with the Senhance was reviewed at a single hospital. Data including operative time, console time, set up time, and adverse events were collected, with clinical outcome and operative time as primary outcome measures. A cohort of 20 patients having laparoscopic cholecystectomy performed by the same surgeon was used as a comparator group. Results. The 2 groups had comparable demographic data (age, sex, and body mass index). In the Senhance group, 19 of the 20 procedures (95%) were completed robotically. The median (interquartile range) total operating, docking, and console times were 86.5 (60.5-106.5), 11.5 (9-13), and 30.8 (23.5-35) minutes, respectively. In the laparoscopic group, the median (interquartile range) operating time was 31.5 (26-41) minutes. Postoperatively, only one patient had a surgical complication, namely a wound infection treated with antibiotics. Conclusion. Our results suggest that Senhance-assisted cholecystectomy is safe, feasible, and effective, but currently has longer operative times. Further prospective and randomized trials are required to determine whether this approach can offer any other benefits over other minimally invasive surgical techniques.

Current margin practice and effect on re-excision rates following the publication of the SSO-ASTRO consensus and ABS consensus guidelines: a national prospective study of 2858 women undergoing breast-conserving therapy in the UK and Ireland.

INTRODUCTION: There is variation in margin policy for breast conserving therapy (BCT) in the UK and Ireland. In response to the Society of Surgical Oncology and American Society for Radiation Oncology (SSO-ASTRO) margin consensus ('no ink on tumour' for invasive and 2 mm for ductal carcinoma in situ [DCIS]) and the Association of Breast Surgery (ABS) consensus (1 mm for invasive and DCIS), we report on current margin practice and unit infrastructure in the UK and Ireland and describe how these factors impact on re-excision rates. METHODS: A trainee collaborative-led multicentre prospective study was conducted in the UK and Ireland between 1st February and 31st May 2016. Data were collected on consecutive BCT patients and on local infrastructure and policies. RESULTS: A total of 79 sites participated in the data collection (75% screening units; average 372 cancers annually, range 70-900). For DCIS, 53.2% of units accept 1 mm and 38% accept 2-mm margins. For invasive disease 77.2% accept 1 mm and 13.9% accept 'no ink on tumour'. A total of 2858 patients underwent BCT with a mean re-excision rate of 17.2% across units (range 0-41%). The re-excision rate would be reduced to 15% if all units applied SSO-ASTRO guidelines and to 14.8% if all units followed ABS guidelines. Of those who required re-operation, 65% had disease present at margin. CONCLUSION: There continues to be large variation in margin policy and re-excision rates across units. Altering margin policies to follow either SSO-ASTRO or ABS guidelines would result in a modest reduction in the national re-excision rate. Most re-excisions are for involved margins rather than close margins.

The Effects of Bariatric Surgery on Cardiac Structure and Function: a Systematic Review of Cardiac Imaging Outcomes.

BACKGROUND: Obesity is associated with cardiac dysfunction, atherosclerosis, and increased cardiovascular risk. It can be lead to obesity cardiomyopathy and severe heart failure, which in turn raise morbidity and mortality while carrying a negative impact on quality of life. There is increasing clinical and mechanistic evidence on the metabolic and weight loss effects of bariatric surgery on improving cardiac structure and function in obese patients. OBJECTIVES: The objective of this study was to quantify the effects of bariatric surgery on cardiac structure and function by appraising cardiac imaging changes before and after metabolic operations. METHODS: This is a comprehensive systematic review of studies reporting pre-operative and post-operative echocardiographic or magnetic resonance cardiac indices in obese patients undergoing bariatric surgery. Studies were quality scored, and data were meta-analyzed using random effects modeling. RESULTS: Bariatric surgery is associated with significant improvements in the weighted incidence of a number of cardiac indices including a decrease in left ventricular mass index (11.2%, 95% confidence intervals (CI) 8.2-14.1%), left ventricular end-diastolic volume (13.28 ml, 95% CI 5.22-21.34 ml), and left atrium diameter (1.967 mm, 95% CI 0.980-2.954). There were beneficial increases in left ventricular ejection fraction (1.198%, 95%CI -0.050-2.347) and E/A ratio (0.189%, 95%CI -0.113-0.265). CONCLUSIONS: Bariatric surgery offers beneficial cardiac effects on diastolic function, systolic function, and myocardial structure in obese patients. These may derive from surgical modulation of an enterocardiac axis. Future studies must focus on higher evidence levels to better identify the most successful bariatric approaches in preventing and treating the broad spectrum of obesity-associated heart disease while also enhancing treatment strategies in the management of obesity cardiomyopathy.

Biomedical applications of carbon-nanotube composites.

The unique physical, chemical and mechanical properties of carbon nanotubes make them attractive for a variety of biomedical applications. Carbon nanotubes have been used to modify conventional biomedical materials to enhance mechanical properties, biocompatibility, or to impart other functionalities. New multifunctional composite materials using carbon nanotubes have been developed by combining them with inorganic, polymeric or biological materials. The biomedical applications for which novel carbon nanotube composites have been investigated include antimicrobial coatings, neural implants, tissue engineering scaffolds and electrochemical biosensors. In this paper, research on development and application of carbon nanotube composites for biomedical applications has been reviewed.

Semipolar r-plane ZnO films on Si(100) substrates: Thin film epitaxy and optical properties.

We report heteroepitaxial growth of (101 2) oriented (r-plane) ZnO films on Si(100) substrates. The films were grown by pulsed laser deposition and integration of ZnO with silicon was achieved using a tetragonal yttria stabilized zirconia (YSZ) buffer layer. It was observed that ZnO films grown at temperatures in the range of 700-750 degrees C with relatively high oxygen pressure ( approximately 70 mTorr) were (101 2) oriented. ZnO films deposited with lower oxygen pressures were found to be purely (0002) orientated. Experiments carried out to elucidate the role of oxygen pressure indicated that the crystallographic orientation of ZnO depends on the nature of atomic termination of YSZ layer. It has been proposed that crystallographic orientation of ZnO is controlled by chemical free energy associated with ZnO-YSZ interface. Detailed x-ray diffraction and transmission electron microscopy studies showed existence of four types of in-plane domains in r-plane ZnO films. Optical characterization demonstrated that photoluminescence of r-plane ZnO films was superior to that of c-plane ZnO films grown under similar conditions.

Highly efficient recyclable hydrated-clay supported catalytic system for atom transfer radical polymerization.

Atom transfer radical polymerization of methacrylates has been performed using hydrated natural clay as a support for a CuBr(2)-ligand complex and the supported clay catalyst has been recycled for 21 batch polymerizations without losing its activity.

Piezoelectric inkjet printing of a cross-hatch immunoassay on a disposable nylon membrane.

The development of a cost-effective method for manufacturing immunoassays is a key step towards their commercial use. In this study, a piezoelectric inkjet printer and a nylon membrane were used to fabricate a disposable immunoassay. Using a piezoelectric inkjet printer, a cross-hatch pattern of goat anti-mouse antibody (GalphaM) and rabbit anti-horseradish peroxidase (RalphaHRP) antibody were deposited on the nylon membrane. These patterns were subsequently treated with a solution containing rabbit anti-goat antibody labeled with horseradish peroxidase (RalphaG-HRP). The effectiveness of the immobilization process was examined using tetramethylbenzidine (TMB), which oxidizes in the presence of HRP to form a visible precipitate. Optical evaluation of the TMB precipitate was used to assess the precision of the features in the inkjet-printed pattern as well as antibody functionality following inkjet printing. Uniform patterns that contained functional antibodies were fabricated using the piezoelectric inkjet printer. These results suggest that piezoelectric inkjet printing may be used to fabricate low-cost disposable immunoassays for biotechnology and healthcare applications.

Mechanical and biological properties of nanoporous carbon membranes.

Implantable blood glucose sensors have inadequate membrane-tissue interfaces for long term use. Biofouling and inflammation processes restrict biosensor membrane stability. An ideal biosensor membrane material must prevent protein adsorption and exhibit cell compatibility. In addition, a membrane must exhibit high porosity and low thickness in order to allow the biosensor to respond to analyte fluctuations. In this study, the structural, mechanical and biological properties of nanoporous alumina membranes coated with diamond-like carbon thin films were examined using scanning probe microscopy, nanoindentation and MTT viability assay. We anticipate that this novel membrane material could find use in immunoisolation devices, kidney dialysis membranes and other medical devices encountering biocompatibility issues that limit in vivo function.

Pulsed laser deposition of nanoporous cobalt thin films.

Nanoporous cobalt thin films were deposited on anodized aluminum oxide (AAO) membranes at room temperature using pulsed laser deposition. Scanning electron microscopy demonstrated that the nanoporous cobalt thin films retained the monodisperse pore size and high porosity of the anodized aluminum oxide substrates. Temperature- and field-dependent magnetic data obtained between 10 K and 350 K showed large hysteresis behavior in these materials. The increase of coercivity values was larger for nanoporous cobalt thin films than for multilayered cobalt/alumina thin films. The average diameter of the cobalt nanograins in the nanoporous cobalt thin films was estimated to be approsimately 5 nm for blocking temperatures near room temperature. These results suggest that pulsed laser deposition may be used to fabricate nanoporous magnetic materials with unusual properties for biosensing, drug delivery, data storage, and other technological applications.