Peri-operative COVID-19 infection in urgent elective surgery during a pandemic surge period: a retrospective observational cohort study.

Maintaining safe elective surgical activity during the global coronavirus disease 2019 (COVID-19) pandemic is challenging and it is not clear how COVID-19 may impact peri-operative morbidity and mortality in this population. Therefore, adaptations to normal care pathways are required. Here, we establish if implementation of a bespoke peri-operative care bundle for urgent elective surgery during a pandemic surge period can deliver a low COVID-19-associated complication profile. We present a single-centre retrospective cohort study from a tertiary care hospital of patients planned for urgent elective surgery during the initial COVID-19 surge in the UK between 29 March and 12 June 2020. Patients asymptomatic for COVID-19 were screened by oronasal swab and chest imaging (chest X-ray or computed tomography if aged ≥ 18 years), proceeding to surgery if negative. COVID-19 positive patients at screening were delayed. Postoperatively, patients transitioning to COVID-19 positive status by reverse transcriptase polymerase chain reaction testing were identified by an in-house tracking system and monitored for complications and death within 30 days of surgery. Out of 557 patients referred for surgery (230 (41.3%) women; median (IQR [range]) age 61 (48-72 [1-89])), 535 patients (96%) had COVID-19 screening, of which 13 were positive (2.4%, 95%CI 1.4-4.1%). Out of 512 patients subsequently undergoing surgery, 7 (1.4%) developed COVID-19 positive status (1.4%, 95%CI 0.7-2.8%) with one COVID-19-related death (0.2%, 95%CI 0.0-1.1%) within 30 days. Out of these seven patients, four developed pneumonia, of which two required invasive ventilation including one patient with acute respiratory distress syndrome. Low rates of COVID-19 infection and mortality in the elective surgical population can be achieved within a targeted care bundle. This should provide reassurance that elective surgery can continue, where possible, despite high community rates of COVID-19.

Succinate dehydrogenase mutations: paraganglioma imaging and at-risk population screening.

Paragangliomas are rare vascular tumours of the autonomic nervous system. They can be classified as sympathetic or parasympathetic. Sympathetic paragangliomas, which include phaeochromocytomas, tend to be functional and symptomatic. Parasympathetic paragangliomas are usually non-functional and may present with mass effect. Forty percent of paragangliomas are linked to genetic syndromes, most commonly due to mutations of the succinate dehydrogenase (SDH) enzyme complex and are collectively known as paraganglioma syndromes, of which five are described. Genetic testing is recommended for all patients, and their first-degree relatives, diagnosed with paragangliomas. When SDH mutations are discovered, biochemical screening and imaging surveillance is indicated. There is currently no consensus on imaging surveillance protocols. Most advocate full-body imaging, but the choice of technique and frequency varies. If paragangliomas are demonstrated, functional imaging to look for synchronous tumours or metastases is indicated. 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)-computed tomography (CT) is the technique of choice for metastatic evaluation, but [123I]-metaiodobenzylguanidine or [111In]-DTPA-octreotide scintigraphy are also utilised. Current research into emerging positron-emitting radiolabelled somatostatin analogues have yielded promising results, which is likely to be reflected in future guidelines. As genetic testing becomes increasingly prevalent, the need to answer the remaining questions regarding surveillance imaging is paramount.

Thermal Desorption Analysis of Hydrogen in Non-hydrogen-Charged Rolling Contact Fatigue-Tested 100Cr6 Steel.

Hydrogen diffusion during rolling contact fatigue (RCF) is considered a potential root cause or accelerator of white etching cracks (WECs) in wind turbine gearbox bearing steels. Hydrogen entry into the bearing steel during operation is thought to occur either through the contact surface itself or through cracks that breach the contact surface, in both cases by the decomposition of lubricant through catalytic reactions and/or tribochemical reactions of water. Thermal desorption analysis (TDA) using two experimental set-ups has been used to measure the hydrogen concentration in non-hydrogen-charged bearings over increasing RCF test durations for the first time. TDA on both instruments revealed that hydrogen diffused into the rolling elements, increasing concentrations being measured for longer test durations, with numerous WECs having formed. On the other hand, across all test durations, negligible concentrations of hydrogen were measured in the raceways, and correspondingly no WECs formed. Evidence for a relationship between hydrogen concentration and either the formation or the acceleration of WECs is shown in the rollers, as WECs increased in number and severity with increasing test duration. It is assumed that hydrogen diffusion occurred at wear-induced nascent surfaces or areas of heterogeneous/patchy tribofilm, since most WECs did not breach the contact surface, and those that did only had very small crack volumes for entry of lubricant to have occurred.

The Evolution of White Etching Cracks (WECs) in Rolling Contact Fatigue-Tested 100Cr6 Steel.

The formation of white etching cracks (WECs) in steel rolling element bearings can lead to the premature rolling contact fatigue (RCF) failure mode called white structure flaking. Driving mechanisms are still debated but are proposed to be combinations of mechanical, tribochemical and electrical effects. A number of studies have been conducted to record and map WECs in RCF-tested samples and bearings failed from the field. For the first time, this study uses serial sectioning metallography techniques on non-hydrogen charged test samples over a range of test durations to capture the evolution of WEC formation from their initiation to final flaking. Clear evidence for subsurface initiation at non-metallic inclusions was observed at the early stages of WEC formation, and with increasing test duration the propagation of these cracks from the subsurface region to the contact surface eventually causing flaking. In addition, an increase in the amount of associated microstructural changes adjacent to the cracks is observed, this being indicative of the crack being a prerequisite of the microstructural alteration.

Global lessons: developing military trauma care and lessons for civilian practice.

The wars in Iraq and Afghanistan have helped to shape the modern Defence Medical Services. Many lessons were learnt including the need for rapid haemorrhage control, senior decision-making and the evolution of deployed transfusion support. These changes were implemented simultaneously with a coherent, end-to-end medical plan from point of wounding through to rehabilitation. Implementation of the medical plan is harmonious with the NHS trauma pathway, and is key to ensuring effective delivery. Military anaesthetists have a long pre-deployment training pathway starting with a Certificate of Completion of Training (CCT) in anaesthesia and/or critical care, and with an emphasis on military skills related to their specific role. Pre-deployment training includes additional skill training, team training and finally whole hospital collective training. This pathway ensures ongoing and continuing competence on an individual basis, and assurance that hospital management systems and clinical staff can function effectively as a deploying unit.

Early activation of microglia and astrocytes in mouse models of spinocerebellar ataxia type 1.

Spinocerebellar ataxia type 1 (SCA1) is an incurable, dominantly inherited neurodegenerative disease of the cerebellum caused by a polyglutamine-repeat expansion in the protein ataxin-1 (ATXN1). While analysis of human autopsy material indicates significant glial pathology in SCA1, previous research has focused on characterizing neuronal dysfunction. In this study, we characterized astrocytic and microglial response in SCA1 using a comprehensive array of mouse models. We have discovered that astrocytes and microglia are activated very early in SCA1 pathogenesis even when mutant ATXN1 expression was limited to Purkinje neurons. Glial activation occurred in the absence of neuronal death, suggesting that glial activation results from signals emanating from dysfunctional neurons. Finally, in all different models examined glial activation closely correlated with disease progression, supporting the development of glial-based biomarkers to follow disease progression.

Who are we missing? Too few skeletal surveys for children with humeral and femoral fractures.

AIM: To determine the potential shortfall in skeletal survey referral for children presenting with an acute non-supracondylar humeral or femoral fracture. MATERIALS AND METHODS: Plain radiograph reports were reviewed retrospectively using the radiology information system database over a 5 year study period (May 2008-2013) in children under 18 months of age who presented with an acute fracture. Subsequent skeletal survey referral was used as a surrogate marker for further investigation of child abuse. Application of robust meta-analysis derived probability data regarding likelihood of child abuse as a cause of non-supracondylar humeral or femoral fracture was applied. An estimation of the expected number of cases of abuse, with shortfall in skeletal survey referrals, was then calculated. RESULTS: There were 288 fractures in 281 children. Three children presented with multiple fractures and were considered separately in the present data. The mean patient age was 10.5 months. Nine (3%) non-supracondylar humeral fractures were identified of which four cases may have been due to non-accidental injury (NAI). One (11%) of these patients was referred for a skeletal survey indicating a potential shortfall of three referrals. Twenty-five (9%) femoral fractures were identified of which 13 cases may have been due to NAI, with six (24%) referrals for skeletal surveys generated. This indicates a potential shortfall of seven referrals. CONCLUSION: The present study serves as a current analysis of practice within a tertiary paediatric referral centre. There appeared to be local under-investigation of NAI. Improved child protection education and awareness programmes have now been introduced.

Scores on the MMPI-2-RF scales as a function of increasing levels of failure on cognitive symptom validity tests in a military sample.

This research examined associations between the full range of Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) validity and substantive scales and increasing levels of cognitive symptom validity test (SVT) failure in a sample of 501 military members who completed a neuropsychological evaluation primarily for mild traumatic brain injury resulting from a closed head injury and blast exposure or heat injury. SVT failure was associated with significant linear increases in all of the over-reporting MMPI-2-RF validity scales and most of the substantive scales. For the validity scales, all over-reporting scales had large effect sizes (ESs) when comparing a group that failed no SVTs with a group that failed three SVTs. A comparison between these two groups for the substantive scales revealed the largest ESs for scales related to somatic/cognitive complaints and emotional dysfunction. RBS (Response Bias Scale) had the largest ES of all scales (d = 1.69), followed by FBS-r (Symptom Validity Scale; d = 1.34), AXY (Anxiety, d = 1.21), and COG (Cognitive Complaints, d = 1.19). The scales related to behavioral dysfunction had the smallest ESs of all of the substantive scales, and there were no significant associations between the vast majority of these scales and SVT failure. With respect to clinically significant elevations, those who did not fail SVTs had clinically significant elevations only on COG and NUC (Neurological Complaints), and MLS (Malaise) approached clinical significance. For those who failed SVTs, RBS was the only over-reporting scale that was elevated across all failure groups. Those who failed any SVT had clinically significant elevations on COG, MLS, NUC, and AXY. Those who failed three SVTs had additional elevations on scales related to emotional dysfunction.

A comparison of selected MMPI-2 and MMPI-2-RF validity scales in assessing effort on cognitive tests in a military sample.

Using a relatively new statistical paradigm, Optimal Data Analysis (ODA; Yarnold & Soltysik, 2005), this research demonstrated that newly developed scales for the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and MMPI-2 Restructured Form (MMPI-2-RF) specifically designed to assess over-reporting of cognitive and/or somatic symptoms were more effective than the MMPI-2 F-family of scales in predicting effort status on tests of cognitive functioning in a sample of 288 military members. ODA demonstrated that when all scales were performing at their theoretical maximum possible level of classification accuracy, the Henry Heilbronner Index (HHI), Response Bias Scale (RBS), Fake Bad Scale (FBS), and the Symptom Validity Scale (FBS-r) outperformed the F-family of scales on a variety of ODA indexes of classification accuracy, including an omnibus measure (effect strength total, EST) of the descriptive and prognostic utility of ODA models developed for each scale. Based on the guidelines suggested by Yarnold and Soltysik for evaluating effect strengths for ODA models, the newly developed scales had effects sizes that were moderate in size (37.66 to 45.68), whereas the F-family scales had effects strengths that ranged from weak to moderate (15.42 to 32.80). In addition, traditional analysis demonstrated that HHI, RBS, FBS, and FBS-R had large effect sizes (0.98 to 1.16) based on Cohen's (1988) suggested categorization of effect size when comparing mean scores for adequate versus inadequate effort groups, whereas F-family of scales had small to medium effect sizes (0.25 to 0.76). The MMPI-2-RF Infrequent Somatic Responses Scale (F(S)) tended to perform in a fashion similar to F, the best performing F-family scale.

Acute pancreatitis with saw palmetto use: a case report.

INTRODUCTION: Saw palmetto is a phytotherapeutic agent commercially marketed for the treatment of benign prostatic hyperplasia. Evidence suggests that saw palmetto is a safe product, and mild gastrointestinal adverse effects have been reported with its use. We report a case of acute pancreatitis, possibly secondary to the use of saw palmetto. CASE PRESENTATION: A 61-year-old Caucasian man with a history of benign prostatic hyperplasia and gastroesophageal reflux disease developed epigastric pain associated with nausea 36 hours prior to presentation. He denied drinking alcohol prior to the development of his symptoms. His home medications included saw palmetto, lansoprazole and multivitamins. Laboratory results revealed elevated lipase and amylase levels. An abdominal ultrasound demonstrated a nondilated common bile duct, without choledocholithiasis. Computed tomography of his abdomen showed the pancreatic tail with peripancreatic inflammatory changes, consistent with acute pancreatitis. Our patient's condition improved with intravenous fluids and pain management. On the fourth day of hospitalization his pancreatic enzymes were within normal limits: he was discharged home and advised to avoid taking saw palmetto. CONCLUSION: It is our opinion that a relationship between saw palmetto and the onset of acute pancreatitis is plausible, and prescribers and users of saw palmetto should be alert to the possibility of such adverse reactions.

Composite adenocarcinoma and carcinoid gastric tumor in chronic atrophic gastritis and pernicious anemia.

A 42-year-old Hispanic female was referred for investigation of unexplained weight loss. Initial upper endoscopy showed atrophic gastritis. Repeat endoscopy one year later revealed the presence of mixed composite tumor consisting of gastric adenocarcinoma and carcinoid tumors. Treatment was accomplished by surgical excision. Such cases are extremely rare and few such reports are available in the literature. We discuss the pathologies and means by which these tumors are classified and treated.

Use of thromboelastometry in the assessment of coagulation before epidural insertion after massive transfusion.

A British soldier presented to the UK Field Hospital, Afghanistan with bilateral traumatic lower limb amputations. Resuscitation and surgery followed accepted damage control principles. Blood component therapy was in keeping with UK military guidelines and included platelets and cryoprecipitate. The patient's trachea was extubated following insertion of an effective epidural. Ten days later, in the UK, he developed neurological symptoms and the presence of a subdural haematoma was confirmed on magnetic resonance imaging. Conventional laboratory coagulation results in this patient were above accepted limits for epidural insertion; however, thromboelastometry before insertion was suggestive of reduced platelet function. This case highlights the risk of relying solely on platelet count as a marker of platelet function following massive transfusion. Thromboelastometry provides additional information for the assessment of coagulation and should form part of the assessment of coagulation following massive transfusion before epidural insertion.

Effectiveness of a simple intervention for prevention of catheter-associated urinary tract infections in a community teaching hospital.

BACKGROUND: Catheter-associated urinary tract infection (CA-UTI) is the most common health care-associated infection. Instrumentation of the urinary tract, mainly urinary catheterization, is the most important risk factor for CA-UTI. It is believed that proper catheter management can reduce the incidence of CA-UTI. METHODS: This was a prospective preintervention and postintervention study conducted to assess the effect of an intervention aimed at preventing CA-UTI. A reminder sticker was placed on each patient's medical record binder to remind the physicians to consider discontinuing any unnecessary urinary catheters. RESULTS: There was a statistically significant increase in the number of appropriately retained urinary catheters at 3 months (57% vs 73%; P = .007) and 6 months postintervention (57% vs 86%; P < .001). There was also a statistically significant reduction in the rate of CA-UTI after 3 months (7.02 vs 2.08; P < .001) and 6 months postintervention (7.02 vs 2.72; P < .001). CONCLUSION: A simple intervention using a sticker placed on patients' medical record binder to remind physicians to remove unnecessary urinary catheters can significantly increase the appropriate utilization of urinary catheters and decrease the rate of CA-UTI in community teaching hospitals.

Tissue engineered tumor models.

Many research programs use well-characterized tumor cell lines as tumor models for in vitro studies. Because tumor cells grown as three-dimensional (3-D) structures have been shown to behave more like tumors in vivo than do cells growing in monolayer culture, a growing number of investigators now use tumor cell spheroids as models. Single cell type spheroids, however, do not model the stromal-epithelial interactions that have an important role in controlling tumor growth and development in vivo. We describe here a method for generating, reproducibly, more realistic 3-D tumor models that contain both stromal and malignant epithelial cells with an architecture that closely resembles that of tumor microlesions in vivo. Because they are so tissue-like we refer to them as tumor histoids. They can be generated reproducibly in substantial quantities. The bioreactor developed to generate histoid constructs is described and illustrated. It accommodates disposable culture chambers that have filled volumes of either 10 or 64 ml, each culture yielding on the order of 100 or 600 histoid particles, respectively. Each particle is a few tenths of a millimeter in diameter. Examples of histological sections of tumor histoids representing cancers of breast, prostate, colon, pancreas and urinary bladder are presented. Potential applications of tumor histoids include, but are not limited to, use as surrogate tumors for pre-screening anti-solid tumor pharmaceutical agents, as reference specimens for immunostaining in the surgical pathology laboratory and use in studies of invasive properties of cells or other aspects of tumor development and progression. Histoids containing nonmalignant cells also may have potential as "seeds" in tissue engineering. For drug testing, histoids probably will have to meet certain criteria of size and tumor cell content. Using a COPAS Plus flow cytometer, histoids containing fluorescent tumor cells were analyzed successfully and sorted using such criteria.

Case report: Long-term cognitive sequelae of sarin exposure.

The long-term sequelae of acute sarin exposure are not well understood. The largest clinical cohort resulted from the 1994 and 1995 attacks in Japan. Observers noted mostly psychiatric sequelae, with a high prevalence of post-traumatic stress disorder (PTSD). We describe neurocognitive findings that may represent sequelae of low-level sarin exposure in Iraq.

Evaluation of the upper urinary tract using transureteric ultrasound--a review of the technique and typical imaging appearances.

Ureteric strictures and pelviureteric junction obstruction often present a diagnostic conundrum to radiologists, particularly after the first-line investigations have failed to provide a definitive answer. Transureteric ultrasonography (TUU) is a relatively novel technique performed by the radiologist, which uses a miniature endoluminal ultrasound probe to interrogate the ureteric anatomy and peri-ureteric soft tissues. In this review, we discuss how TUU is performed, and the normal imaging appearances of the ureter and surrounding anatomical structures. We also focus on the various pathological processes that can be accurately evaluated or diagnosed using TUU including lymphadenopathy, calculi, ureteric neoplasms, ureteritis, crossing vessels and aneurysms. As TUU is not well established in UK practice as yet, we suggest possible indications for its use in the diagnostic work-up of urological patients and future applications.

Antifungal susceptibility against yeasts isolated from pediatric oncology patients.

Yeast infections cause morbidity in children with cancer and we evaluated species distribution and antifungal susceptibilities of the etiologic agents in this group. Specimens from 58 children yielded 64 cultures positive for yeasts. Central venous catheters were present in 56 (97%) of the children and neutrophil counts were <500 cells/ml3 in 34% of the patients. Twenty-two (38%) had received recent antifungal treatment, with 15 (25%) receiving fluconazole (FLU) prophylaxis. The Candida isolates recovered from four (27%) of the children on FLU prophylaxis, were resistant to this drug. Candida albicans isolates were susceptible to 100% of antifungals tested, whereas non-C. albicans Candida spp. were variable in their susceptibility patterns. FLU prophylaxis minimally affected susceptibility.