David A. K. Watters

Increased Risk of Cognitive Impairment in Patients With Diabetes Is Associated With Metformin

OBJECTIVE To investigate the associations of metformin, serum vitamin B12, calcium supplements, and cognitive impairment in patients with diabetes. RESEARCH DESIGN AND METHODS Participants were recruited from the Primary Research in Memory (PRIME) clinics study, the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging, and the Barwon region of southeastern Australia. Patients with Alzheimer disease (AD) (n = 480) or mild cognitive impairment (n = 187) and those who were cognitively intact (n = 687) were included; patients with stroke or with neurodegenerative diseases other than AD were excluded. Subgroup analyses were performed for participants who had either type 2 diabetes (n = 104) or impaired glucose tolerance (n = 22). RESULTS Participants with diabetes (n = 126) had worse cognitive performance than participants who did not have diabetes (n = 1,228; adjusted odds ratio 1.51 [95% CI 1.03–2.21]). Among participants with diabetes, worse cognitive performance was associated with metformin use (2.23 [1.05–4.75]). After adjusting for age, sex, level of education, history of depression, serum vitamin B12, and metformin use, participants with diabetes who were taking calcium supplements had better cognitive performance (0.41 [0.19–0.92]). CONCLUSIONS Metformin use was associated with impaired cognitive performance. Vitamin B12 and calcium supplements may alleviate metformin-induced vitamin B12 deficiency and were associated with better cognitive outcomes. Prospective trials are warranted to assess the beneficial effects of vitamin B12 and calcium use on cognition in older people with diabetes who are taking metformin.

Global Surgery 2030: evidence and solutions for achieving health, welfare, and economic development.

Remarkable gains have been made in global health in the past 25 years, but progress has not been uniform. Mortality and morbidity from common conditions needing surgery have grown in the world’s poorest regions, both in real terms and relative to other health gains. At the same time, development of safe, essential, life-saving surgical and anesthesia care in low- and middleincome countries (LMICs) has stagnated or regressed. In the absence of surgical care, case-fatality rates are high for common, easily treatable conditions including appendicitis, hernia, fractures, obstructed labor, congenital anomalies, and breast and cervical cancer. Although the term, low- and middleincome countries (LMICs), has been used throughout the report for brevity, the Commission realizes that tremendous income diversity exists between and within this group of countries. In 2015, many LMICs are facing a multifaceted burden of infectious disease, maternal disease, neonatal disease, noncommunicable diseases, and injuries. Surgical and anesthesia care are essential for the treatment of many of these conditions and represent an integral component of a functional, responsive, and resilient health system. In view of the large projected increase in the incidence of cancer, road traffic injuries, and cardiovascular and metabolic diseases in LMICs, the need for surgical services in these regions will continue to rise substantially from now until 2030. Reduction of death and disability hinges on access to surgical and anesthesiacare,whichshouldbeavailable, affordable,timely,andsafetoensuregood coverage, uptake, and outcomes. Despite a growing need, the develop

Role of ultrasound in the management of thyroid nodules

One hundred twenty patients undergoing thyroid surgery for thyroid nodules or goiter were examined by preoperative ultrasound and fine needle aspiration (FNA) cytology. In the determination of whether a lesion was malignant, FNA had sensitivity, specificity, and positive predictive values of 86%, 85%, and 58%, respectively. Ultrasound had sensitivity, specificity, and positive predictive values of 74%, 83%, and 51%, respectively. The different types of thyroid pathology showed different ultrasonic features in most cases, although no single feature was pathognomonic. Malignant lesions tended to be solid and hypoechoic without a halo, but there was a cystic element in 26% of the lesions and calcification in 37%. Ultrasound was superior to FNA in diagnosing nodular goiter with sensitivity, specificity, and positive predictive values of 70%, 93%, and 92%, respectively, compared with 55%, 86%, and 83%, respectively. The two modalities are complementary.

Global cancer surgery: delivering safe, affordable, and timely cancer surgery

Surgery is essential for global cancer care in all resource settings. Of the 15.2 million new cases of cancer in 2015, over 80% of cases will need surgery, some several times. By 2030, we estimate that annually 45 million surgical procedures will be needed worldwide. Yet, less than 25% of patients with cancer worldwide actually get safe, affordable, or timely surgery. This Commission on global cancer surgery, building on Global Surgery 2030, has examined the state of global cancer surgery through an analysis of the burden of surgical disease and breadth of cancer surgery, economics and financing, factors for strengthening surgical systems for cancer with multiple-country studies, the research agenda, and the political factors that frame policy making in this area. We found wide equity and economic gaps in global cancer surgery. Many patients throughout the world do not have access to cancer surgery, and the failure to train more cancer surgeons and strengthen systems could result in as much as US

Cognitive impairment and vitamin B12: a review

6.2 trillion in lost cumulative gross domestic product by 2030. Many of the key adjunct treatment modalities for cancer surgery--e.g., pathology and imaging--are also inadequate. Our analysis identified substantial issues, but also highlights solutions and innovations. Issues of access, a paucity of investment in public surgical systems, low investment in research, and training and education gaps are remarkably widespread. Solutions include better regulated public systems, international partnerships, super-centralisation of surgical services, novel surgical clinical trials, and new approaches to improve quality and scale up cancer surgical systems through education and training. Our key messages are directed at many global stakeholders, but the central message is that to deliver safe, affordable, and timely cancer surgery to all, surgery must be at the heart of global and national cancer control planning.

Perioperative Mortality Rate (POMR): A Global Indicator of Access to Safe Surgery and Anaesthesia

BACKGROUND This review examines the associations between low vitamin B12 levels, neurodegenerative disease, and cognitive impairment. The potential impact of comorbidities and medications associated with vitamin B12 derangements were also investigated. In addition, we reviewed the evidence as to whether vitamin B12 therapy is efficacious for cognitive impairment and dementia. METHODS A systematic literature search identified 43 studies investigating the association of vitamin B12 and cognitive impairment or dementia. Seventeen studies reported on the efficacy of vitamin B12 therapy for these conditions. RESULTS Vitamin B12 levels in the subclinical low-normal range (<250 ρmol/L) are associated with Alzheimers disease, vascular dementia, and Parkinsons disease. Vegetarianism and metformin use contribute to depressed vitamin B12 levels and may independently increase the risk for cognitive impairment. Vitamin B12 deficiency (<150 ρmol/L) is associated with cognitive impairment. Vitamin B12 supplements administered orally or parenterally at high dose (1 mg daily) were effective in correcting biochemical deficiency, but improved cognition only in patients with pre-existing vitamin B12 deficiency (serum vitamin B12 levels <150 ρmol/L or serum homocysteine levels >19.9 μmol/L). CONCLUSION Low serum vitamin B12 levels are associated with neurodegenerative disease and cognitive impairment. There is a small subset of dementias that are reversible with vitamin B12 therapy and this treatment is inexpensive and safe. Vitamin B12 therapy does not improve cognition in patients without pre-existing deficiency. There is a need for large, well-resourced clinical trials to close the gaps in our current understanding of the nature of the associations of vitamin B12 insufficiency and neurodegenerative disease.

Cumulative sum techniques for surgeons: a brief review.

IntroductionThe unmet global burden of surgical disease is substantial. Currently, two billion people do not have access to emergency and essential surgical care. This results in unnecessary deaths from injury, infection, complications of pregnancy, and abdominal emergencies. Inadequately treated surgical disease results in disability, and many children suffer deformity without corrective surgery.MethodsA consensus meeting was held between representatives of Surgical and Anaesthetic Colleges and Societies to obtain agreement about which indicators were the most appropriate and credible. The literature and state of national reporting of perioperative mortality rates was reviewed by the authors.ResultsThere is a need for a credible national and/or regional indicator that is relevant to emergency and essential surgical care. We recommend introducing the perioperative mortality rate (POMR) as an indicator of access to and safety of surgery and anaesthesia. POMR should be measured at two time periods: death on the day of surgery and death before discharge from hospital or within 30 days of the procedure, whichever is sooner. The rate should be expressed as the number of deaths (numerator) over the number of procedures (denominator). The option of before-discharge or 30 days is practical for those low- to middle-income countries where postdischarge follow-up is likely to be incomplete, but it allows those that currently can report 30-day mortality rates to continue to do so. Clinical interpretation of POMR at a hospital or health service level will be facilitated by risk stratification using age, urgency (elective and emergency), procedure/procedure group, and the American Society of Anesthesiologists grade.ConclusionsPOMR should be reported as a health indicator by all countries and regions of the world. POMR reporting is feasible, credible, achieves a consensus of acceptance for reporting at national level. Hospital and Service level POMR requires interpretation using simple measures of risk adjustment such as urgency, age, the condition being treated or the procedure being performed and ASA status.

Global Surgery 2030: Evidence and solutions for achieving health, welfare, and economic development

There has been increasing awareness of the need for monitoring the quality of health care, particularly in the area of surgery. The Cumulative Summation (Cusum) techniques have emerged as a popular tool for performance monitoring in surgery. They allow one to judge whether a given variation in performance is probably due to chance or greater than could be expected from random variation and thus a cause for concern. The Cusum techniques are simple to carry out and can be applied to any surgical process with a binary outcome. Four parameters need to be set in advance: acceptable outcome rate, unacceptable outcome rate, Type I and Type II error rates. In this article, we review the history, statistical methods and potential applications for the Cusum techniques in the field of surgery and illustrate the two common forms of charting (cumulative failure and Cusum charting) by using unadjusted outcome data from the Geelong Hospital and St Vincent’s Hospital cardiac surgery databases.

A systematic review of the management and outcome of toxic epidermal necrolysis treated in burns centres

John G Meara*, Andrew J M Leather*, Lars Hagander*, Blake C Alkire, Nivaldo Alonso, Emmanuel A Ameh, Stephen W Bickler, Lesong Conteh, Anna J Dare, Justine Davies, Eunice Dérivois Mérisier, Shenaaz El-Halabi, Paul E Farmer, Atul Gawande, Rowan Gillies, Sarah L M Greenberg, Caris E Grimes, Russell L Gruen, Edna Adan Ismail, Thaim Buya Kamara, Chris Lavy, Ganbold Lundeg, Nyengo C Mkandawire, Nakul P Raykar, Johanna N Riesel, Edgar Rodas‡, John Rose, Nobhojit Roy, Mark G Shrime, Richard Sullivan, Stéphane Verguet, David Watters, Thomas G Weiser, Iain H Wilson, Gavin Yamey, Winnie Yip

Guide to the Assessment of Competence and Performance in Practising Surgeons

INTRODUCTION Toxic epidermal necrolysis (TEN) is a rare condition characterised by mucocutaneous exfoliation of greater than 30% total body surface area (%TBSA), increasingly being treated in burns centres. The rate of mortality varies significantly in the literature, with recent prospective studies in non-burns centres reporting percentage mortality of approximately 45%. We undertook a systematic review of published studies that included TEN patients treated specifically in burns centres to determine a cumulative mortality rate. METHODS Electronic searches of MEDLINE, EMBASE and The Cochrane Library (Issue 4, 2010) databases from 1966 onwards were used to identify English articles related to the treatment of TEN in burns centres. RESULTS The systematic literature search identified 20 studies which specifically described patients with TEN grater than 30% %TBSA. Treatment regimens varied amongst studies, as did mortality. The overall percentage mortality of the combined populations was 30%. Risk factors commonly described as associated with mortality included age, %TBSA and delay to definitive treatment. CONCLUSION The review highlights the variation between principles of treatment and mortality amongst burns centres. It offers a standard that burns centre can use to internationally compare their mortality rates. The review supports the ongoing reporting of outcomes in TEN patients with epidermal detachment greater than 30%.