Simon P Rowland

Metabolic surgery and cancer: protective effects of bariatric procedures.

The worldwide epidemic of obesity and the global incidence of cancer are both increasing. There is now epidemiological evidence to support a correlation between obesity, weight gain, and some cancers. Metabolic or bariatric surgery can provide sustained weight loss and reduced obesity‐related mortality. These procedures can also improve the metabolic profile to decrease cardiovascular risk and resolve diabetes in morbidly obese patients. The operations offer several physiological steps, the so‐called BRAVE effects: 1) bile flow alteration, 2) reduction of gastric size, 3) anatomical gut rearrangement and altered flow of nutrients, 4) vagal manipulation and 5) enteric gut hormone modulation. Metabolic operations are also associated with a significant reduction of cancer incidence and mortality. The cancer‐protective role of metabolic surgery is strongest for female obesity‐related tumors; however, the underlying mechanisms may involve both weight‐dependent and weight‐independent effects. These include the improvement of insulin resistance with attenuation of the metabolic syndrome as well as decreased oxidative stress and inflammation in addition to the beneficial modulation of sex steroids, gut hormones, cellular energetics, immune system, and adipokines. Elucidating the precise metabolic mechanisms of cancer prevention by metabolic surgery can increase our understanding of how obesity, diabetes, and metabolic syndrome are associated with cancer. It may also offer novel treatment strategies in the management of tumor generation and growth. Cancer 2011.

Body Mass Index Category as a Risk Factor for Colorectal Adenomas: A Systematic Review and Meta-Analysis

OBJECTIVES:The association between increasing body weight and colorectal adenoma prevalence has been suggested to follow a similar pattern to excess weight and colorectal cancer, although the magnitude of this relationship has not been validated. The objective of this study was to quantify the association and dose–response relationship between body mass index (BMI) and colorectal adenoma prevalence in clinical trials.METHODS:We systematically reviewed 23 studies (168,201 participants), which compared the prevalence of colorectal adenomas according to World Health Organization BMI categories. We assessed the effects of each BMI category on colorectal adenomas where odds ratio (OR) was used as a surrogate for effect size, and applied multivariate meta-analysis as a method of sensitivity analysis to evaluate the robustness of our findings and to analyze adenoma prevalence by multiple BMI categories simultaneously to assess for a dose–response relationship. Heterogeneity and publication bias were assessed.RESULTS:Subjects with a BMI of ≥25 had a significantly higher prevalence of colorectal adenomas (OR=1.24 (95% confidence interval (CI): 1.16–1.33), P<0.01) when compared with those with BMI<25. Multivariate meta-analysis also confirmed a positive association between higher BMI categories and the prevalence of colorectal adenoma (BMI: 25–30 vs. BMI<25; OR=1.21 (95% CI: 1.07–1.38), P<0.01; BMI≥30 vs. BMI<25; OR=1.32 (95% CI: 1.18–1.48), P<0.01) and revealed a dose–response relationship.CONCLUSIONS:The positive association between obesity and colorectal adenoma prevalence demonstrates an underlying dose–response relationship according to BMI. Colorectal centers may benefit from the timely screening of obese patients for colorectal adenomas in addition to clarifying the biological role of adiposity on colorectal tumor initiation and progression.

Metabolic surgery and obstructive sleep apnoea: the protective effects of bariatric procedures

The global epidemic of obesity and the worldwide prevalence of obstructive sleep apnoea (OSA) are both increasing. Epidemiological studies reveal an association between obesity, weight gain and OSA. Metabolic or bariatric operations provide sustained weight loss and resolve or improve the symptoms of OSA in the majority of morbidly obese individuals. These operations also modulate the metabolic profile to improve glycaemic control, to decrease cardiovascular risk and obesity-related mortality. The beneficial effects of metabolic operations on OSA include mechanical weight-dependent and metabolic weight-independent effects that are achieved through the BRAVE effects: (Bile flow alteration; Reduction of gastric size; Anatomical gut rearrangement and altered flow of nutrients; Vagal manipulation; and Enteric gut hormone modulation). These result in an improvement in insulin resistance, adipokines, cytokines and systemic inflammation. A literature analysis was performed with statistical pooling of available surgical and medical studies to determine whether the weighted mean decrease in body mass index and sleep apnoea severity (measured by the apnoea-hypopnoea index) are larger in metabolic surgical studies than in non-surgical weight loss studies (diet, exercise and medication). However, heterogeneity across available trials, poor follow-up measures and a deficiency in comparative studies between surgical and non-surgical therapy precludes definitive statements regarding the relative benefits of surgical therapy. Further research is required to quantify robustly the effects and mechanisms of sleep apnoea resolution by metabolic surgery, which may reveal novel non-surgical treatments or enhanced surgical strategies in the management of this multisystem sleep disorder.

Is the structure of anatomy curriculum adequate for safe medical practice

INTRODUCTION Anatomy has been considered a core subject within the medical education curriculum. In the current setting of ever-changing diagnostic and treatment modalities, the opinion of both students and trainers is crucial for the design of an anatomy curriculum which fulfils the criteria required for safe medical practice. METHODS Medical students, trainees and specialist trainee doctors and specialists from the London (England) area were surveyed to investigate the how curriculum changes have affected the relevance of anatomical knowledge to clinical practice and to identify recommendations for optimum teaching methods. The survey employed 5-point Likert scales and multiple-choice questions. Where the effect of training level was statistically significant (p < 0.05), post-hoc analysis was carried out using Mann-Whitney U tests. Significance levels were modified according to the Bonferroni method. RESULTS Two hundred and twenty-eight individuals completed the survey giving a response rate of 53%. Medical students, trainees and specialists all agreed (mean Likert score 4.51, 4.79, 4.69 respectively) that knowledge of anatomy is important for medical practice. Most of the trainees (88.4%) and specialists (81.3%) used dissection to learn anatomy, but only 61.4% of medical students used this approach. Dissection was the most commonly recommended approach for learning anatomy across all the groups (41.7%-69.3%). CONCLUSIONS Knowledge of anatomy is perceived to be important for safe clinical practice. Anatomy should be taught with other relevant system or clinical modules. Newer tools for anatomy teaching need further validation before incorporation into the curriculum.

Assessment of anatomical knowledge for clinical practice: perceptions of clinicians and students

PurposeIn anatomy education, assessment may be done by written, practical or oral methods. These are used to varying degrees in UK medical schools with no consensus on the preferred approach. The purpose of this article is to highlight changes to methods of anatomical knowledge assessment utilised in medical schools since the early 1990s and to present recommended methods of assessment according to the level of medical training.MethodsMedical students, trainees and specialists in the London (UK) area were surveyed to: (1) identify methods experienced in anatomy education at medical school and (2) gather recommendations. Medical student, trainee and specialist responses were compared using non-parametric tests.ResultsTwo hundred and twenty-eight individuals responded to the survey giving a response rate of 53%. Subjects who graduated before 2005 were assessed significantly more frequently by practical (94.2 vs. 33.3%) and oral (84.5 vs. 13.1%) methods than those whose graduation year was 2005 or later. Subjects whose graduation year was 2005 or later were assessed significantly more frequently by written methods, such as EMQs than those whose graduation was before 2005 (68.7 vs. 25.2%). Practical examination was identified as the most recommended method of assessment in anatomy education by medical students (59.1%), trainees (all stages combined; 54.2%) and specialists (51.7%).ConclusionPractical assessment is recommended over written and oral methods for the assessment of anatomical knowledge. A formal evaluation of the relative benefits and limitations of available assessment tools is required.

Specialist anatomy: Is the structure of teaching adequate?

BACKGROUND A knowledge and understanding of specialist anatomy, which includes radiological, laparoscopic, endoscopic and endovascular anatomy is essential for interpretation of imaging and development of procedural skills. METHODS AND MATERIALS Medical students, specialist trainees and specialists from the London (England, UK) area were surveyed to investigate individual experiences and recommendations for: (1) timing of the introduction of specialist anatomy teaching, and (2) pedagogical methods used. Opinions relating to radiological, laparoscopic, endoscopic and endovascular anatomy were collected. Non-parametric tests were used to investigate differences in recommendations between specialist trainees and specialists. RESULTS Two hundred and twenty-eight (53%) individuals responded to the survey. Imaging was most commonly used to learn radiological anatomy (94.5%). Procedural observation was most commonly used to learn laparoscopic (89.0%), endoscopic (87.3%) and endovascular anatomy (66.2%). Imaging was the most recommended method to learn radiological anatomy (92.1%). Procedural observation was the most recommended method for learning laparoscopic (80.0%), endoscopic (81.2%) and endovascular anatomy (42.5%). Specialist trainees and specialists recommended introduction of specialist anatomy during undergraduate training. CONCLUSION Although the methods for specialist anatomy learning are in practice, there is no consensus on timing and structure within the anatomy curriculum. Recommendations from trainees and specialists should be considered so that the existing curriculum can be refined to maximise learning outcomes.

Robotic cardiac surgery: advanced minimally invasive technology hindered by barriers to adoption

Robotic cardiac surgery utilizes the most advanced surgical technology to offer patients a minimally invasive alternative to open surgery in the treatment of a broad range of cardiac pathologies. Although robotics may offer substantial benefits to physicians, patients and healthcare institutions, there are important barriers to its adoption that includes inadequate funding, competition from alternate therapies and challenges in training. There is a growing body of evidence to demonstrate the efficacy of robotic cardiac surgery. Technological innovations are improving patient safety and expanding the indications for robotic cardiac surgery beyond the treatment of mitral valve and coronary artery disease. Robotic cardiac surgery is rapidly becoming a feasible, safe and effective option for the definitive treatment of cardiac disease in the context of 21st century challenges to healthcare provision such as diabetes, obesity and an aging population.

Vancomycin-induced thrombocytopaenia in a patient with severe pancreatitis

Vancomycin-induced thrombocytopenia is a rare side effect of a commonly used drug that may cause life-threatening disease. A 51-year-old man was treated for an episode of acute severe alcohol-induced pancreatitis complicated by development of a peripancreatic fluid collection. He developed fever of unknown origin and was treated with intravenous vancomycin and piperacillin with tazobactam. On day 6 of vancomycin therapy his platelet count dropped to 46×109/L (237×109/L on day 1 of treatment) and by day 8 of therapy platelets had fallen to a nadir of 9×109/L. The patient at this stage displayed a florid purpuric rash and haematoma formation on attempted intravenous cannulation. A clinical diagnosis of vancomycin-induced thrombocytopaenia was made and the drug withdrawn. After 3 days a significant improvement in the platelet count was noted, rising to 56 × 109/L. Immunofluorescence testing (PIFT) ruled out teicoplanin and heparin as causes of drug-induced thrombocytopenia.

How to Recruit Patients in Surgical Studies

The process of recruiting patients into any clinical study is fundamentally critical for the implementation, execution and completion of any project. Within this chapter, some of the salient points involved in patient recruitment will be identified and categorised so as to familiarise the reader with the necessary concepts required to recruit patients for a surgical controlled trial.