Radiation dose to staff from medical X-ray scatter in the orthopaedic theatre

PURPOSE

Given the growing demand for intraoperative imaging, there is increased concern for radiation dose for orthopaedic surgical staff. This study sought to determine the distribution of scatter radiation from fluoroscopic imaging in the orthopaedic surgical environment, with particular emphasis on the positions of personnel and the type of orthopaedic surgery performed.

METHODS

A radiation survey detector was deployed at various angles and distances around an anthropomorphic phantom. The scatter dose rate in microsieverts per hour (µSv/h) was recorded using consistent exposure parameters for five common surgical procedures. A C-arm unit produced radiation for the hip arthroscopy, hip replacement and knee simulations, whilst a mini C-arm unit produced fluoroscopy for the foot and hand simulations.

RESULTS

Readings were tabulated, and coloured heatmaps were generated from scatter measurements for each of the five procedures. Positions corresponding to the typical location of the surgical staff (surgeon, surgical assistant, anaesthetist, instrument (scrub) nurse, circulation (scout) nurse and anaesthetic nurse) were superimposed on heatmaps. The surgeon's proximity to the radiation source meant this position experienced the greatest amount of radiation in all five surgical procedures. Mini C-arm doses were considered low in all procedures for positions, with and without lead protection.

CONCLUSION

This investigation demonstrated the distribution of scattered radiation dose experienced at different positions within the orthopaedic surgical theatre. It reinforces the importance of staff increasing their distance from the primary beam where possible, reducing exposure time and increasing shielding with lead protection.

Lameness recovery rates following treatment of dairy cattle with claw horn lameness in the Waikato region of New Zealand

AIMS

To describe the time in days for lame dairy cows to recover after diagnosis and treatment of claw horn lameness, and to investigate whether cure rates differed between farms.

METHODS

Five dairy farms in the Waikato region were conveniently enrolled into a descriptive epidemiological study. Three of these farms had dairy cattle enrolled over two consecutive seasons, while two farms enrolled for one year. Lame cattle diagnosed by the farmers were enrolled into the study if they had a lameness score (LS ≥ 2 on a 0-3 scale) and claw horn lesions. All enrolled animals were treated by a single veterinarian following a consistent methodology, and subsequently assessed for LS at a median frequency of 4 days from enrolment until they were sound (LS = 0). The times (days) taken for animals to become sound and non-lame (LS < 2) were reported for all animals, and Kaplan-Meier survival curves used to present the results. A Cox-proportional hazard model was used to assess if the hazard of soundness was associated with farm, age, breed, lesion, number of limbs involved, and LS at enrolment.

RESULTS

A total of 241 lame cattle with claw horn lesions were enrolled across the five farms. White line disease was the predominant pain-causing lesion in 225 (93%) animals, and blocks were applied to 205 (85%) of enrolled animals. The overall median days from enrolment to becoming sound was 18 (95% CI = 14-21) days, and 7 (95% CI = 7-8) days to become non-lame. A difference in the hazards of lameness cure between farms was identified (p = 0.007), with median days to lameness cure between farms ranging from 11 to 21 days. No associations were identified between age, breed, limb, or LS at enrolment on the lameness cure rates.

CONCLUSIONS

Treatment of claw horn lameness following industry-standard guidelines in dairy cattle on five New Zealand dairy farms resulted in rapid cure, although cure rates differed between farms.

CLINICAL RELEVANCE

Following industry best-practice lameness treatment guidelines, including frequent use of blocks, can result in rapid lameness cure rates in New Zealand dairy cows. This study also suggests that management of lame cattle on pasture can positively benefit their welfare and recovery times. The reported cure rates provide veterinarians with benchmarks on the length of time after which a lame animal should be re-examined, and in the investigation of poor treatment response rates at the herd level.

Awareness of social care needs in people with epilepsy and intellectual disability

BACKGROUND

Nearly a quarter of people with intellectual disability (ID) have epilepsy with large numbers experiencing drug-resistant epilepsy, and premature mortality. To mitigate epilepsy risks the environment and social care needs, particularly in professional care settings, need to be met.

PURPOSE

To compare professional care groups as regards their subjective confidence and perceived responsibility when managing the need of people with ID and epilepsy.

METHOD

A multi-agency expert panel developed a questionnaire with embedded case vignettes with quantitative and qualitative elements to understand training and confidence in the health and social determinants of people with ID and epilepsy. The cross-sectional survey was disseminated amongst health and social care professionals working with people with ID in the UK using an exponential non-discriminative snow-balling methodology. Group comparisons were undertaken using suitable statistical tests including Fisher's exact, Kruskal-Wallis, and Mann-Whitney. Bonferroni correction was applied to significant (p < 0.05) results. Content analysis was conducted and relevant categories and themes were identified.

RESULTS

Social and health professionals (n = 54) rated their confidence to manage the needs of people with ID and epilepsy equally. Health professionals showed better awareness (p < 0.001) of the findings/recommendations of the latest evidence on premature deaths and identifying and managing epilepsy-related risks, including the relevance of nocturnal monitoring. The content analysis highlighted the need for clearer roles, improved care pathways, better epilepsy-specific knowledge, increased resources, and better multi-disciplinary work.

CONCLUSIONS

A gap exists between health and social care professionals in awareness of epilepsy needs for people with ID, requiring essential training and national pathways.

Service user perspectives on social prescribing services for mental health in the UK: a systematic review

AIM

To thematically synthesise adult service users' perspectives on how UK-based social prescribing services support them with their mental health management.

METHODS

Nine databases were systematically searched up to March 2022. Eligible studies were qualitative or mixed methods studies involving participants aged ⩾ 18 years accessing social prescribing services primarily for mental health reasons. Thematic synthesis was applied to qualitative data to create descriptive and analytical themes.

RESULTS

51,965 articles were identified from electronic searches. Six studies were included in the review (n = 220 participants) with good methodological quality. Five studies utilised a link worker referral model, and one study a direct referral model. Modal reasons for referral were social isolation and/or loneliness (n = 4 studies). Two analytical themes were formulated from seven descriptive themes: (1) person-centred care was key to delivery and (2) creating an environment for personal change and development.

CONCLUSIONS

This review provides a synthesis of the qualitative evidence on service users' experiences of accessing and using social prescribing services to support their mental health management. Adherence to principles of person-centred care and addressing the holistic needs of service users (including devoting attention to the quality of the therapeutic environment) are important for design and delivery of social prescribing services. This will optimise service user satisfaction and other outcomes that matter to them.

87. Effectiveness of a Best Practice Advisory in Reducing Inappropriate Urine Cultures

Background

Inappropriate urine cultures can contribute to overutilization of antibiotic treatment for asymptomatic bacteriuria. The objective of this study was to evaluate the appropriateness of urine cultures and the impact of a clinical decision support (CDS) intervention.

Methods

The CDS intervention involved embedding three questions in the urine culture order: whether the patient has fever, leukocytosis or urinary symptoms. When the answer to all three questions is no, a best practice advisory (BPA) alerts the provider that the patient may not meet criteria for a urine culture and suggests cancellation of the order. Cultures obtained in patients experiencing fever, leukocytosis, or urinary symptoms, and those who were pregnant, undergoing invasive urologic procedure, or &lt; 3 years old were classified as appropriate. We performed a quasi-experimental study assessing appropriateness of urine cultures before and after implementation of the BPA. The pre-intervention period was 5/9/19 to 7/31/20 and the intervention period was 2/3/21 to 4/27/21. Random samples of 100 cases from pre- and post-intervention were reviewed to assess appropriateness.

Results

There were 12,679 and 8,270 urine cultures performed pre-intervention and post-intervention, respectively. In 100 cases reviewed pre-intervention, 74% of the cultures were appropriate. Of these, 54% were ordered due to fever or leukocytosis, 50% due to urinary symptoms, and 12% in pregnant women.

Post-intervention, the BPA fired on 458 orders and 106 (23%) were subsequently discontinued. Of the 100 cases reviewed post-intervention, 5 orders were discontinued after the BPA fired. Of the remaining 95 cultures, 78% were appropriate. Of these, 41% were ordered for fever or leukocytosis, 69% for urinary symptoms, and 11% in pregnant women. The change in the proportion of appropriate cultures pre- and post-intervention was not statistically significant (74% vs 78%, respectively, p=0.906).

Conclusion

In nearly one quarter of urine cultures performed, there was not an appropriate indication. Our intervention led to cancellation of 23% urine culture orders and resulted in an absolute increase in 4% of the cultures being ordered appropriately. However, the change in appropriateness was not statistically significant.

Disclosures

All Authors: No reported disclosures

Role of cFOS in mechanosensitive transcriptional regulation in diabetes associated atherosclerosis

 

Atherosclerosis, as manifested clinically by myocardial infarction, stroke and peripheral vascular disease, is a major contributor to cardiovascular disease, the leading cause of death in patients with diabetes. The lipid-laden plaque development within the arterial vessel wall is a progressive process initiated with endothelial cell activation and monocyte adhesion. These cellular events occur primarily at the regions of blood vessels exposed to turbulent blood flow (TBF) and low shear stress such as vascular bends and bifurcations. Exposure of the vascular cells to chronic hyperglycaemia and TBF induces a proatherogenic transcriptional profile. Studies have shown that shear stress regulates vascular pathophysiology via differential regulation of transcription factors (TFs) such as KLF4, EGR1 and AP-1, hence named as mechanosensitive TFs. AP-1 is a heterodimer composed of FOS, Jun and ATF family of TFs. Studies have shown that it is activated by low shear stress in cultured endothelial cells. Increasing evidence supports the vital role of AP-1 family members in inflammation and diabetes-induced myocardial dysfunction. However, gene targets and the mechanisms underlying hyperglycemia-induced activation of AP-1 transcription factor cFOS in vascular regions exposed to TBF are not known.Although a novel approach not previously studied in diabetes associated atherosclerosis, we used a single cell RNA sequencing (scRNA-seq) approach to identify endothelial cells from TBF regions of aorta. Diabetes was induced with streptozotocin (STZ) in Apoe−/− mice and followed for 10 weeks. Cells from digested aortae of control and diabetic mice were subjected to scRNA-seq using 10X Genomics system and Illumina Nova-seq 6000. Unsupervised graph based clustering grouped cells into fourteen cell clusters with similar gene expression profile. We applied a list of mechanosensitive gene markers including EGR1, cFOS, Junb and ICAM1 in scRNA-seq analysis to identify endothelial cells from TBF regions of aorta. This approach identified atheroprone endothelial cells exposed to persistent TBF that showed a distinct transcriptional profile with more than six hundred genes differentially expressed. Importantly, cFOS was the most significantly upregulated gene in endothelial cells exposed to TBF. We next generated adiabetes associated transcriptional signature unique to endothelial cells exposed to TBF as compared to all other cell types in the aorta. We identified several genes in endothelial cells exposed to TBF and hyperglycaemia uniquely dysregulated in diabetic Apoe−/− mice as compared to control mice (cut off = FDR&lt;0.05, fold change at least 2-fold). Gene set enrichment analysis identified “fluid shear stress and atherosclerosis” as most significantly dysregulated pathway in endothelial cells. These novel findings indicate that AP-1 TF subunit cFOS is a potential therapeutic target in diabetes associated atherosclerosis that warrant further experimental exploration.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): National Heart Foundation of Australia

881. Efficacy of Antibiotic Prophylaxis with Vancomycin in Cardiothoracic Surgery

Background

Due to the high incidence of methicillin-resistant Staphylococcus aureus (MRSA) at the Detroit Medical Center, vancomycin is now routinely part of the prophylaxis regimen for cardiothoracic (CT) surgery. The study aims to compare the rate and types of surgical site infections (SSIs) when vancomycin is added to cefazolin for CT surgery compared to cefazolin alone.

Methods

This was a retrospective cohort study conducted at two university-affiliated hospitals. Patients who underwent CT surgery between January 2008 and August 2017 and had a readmission for SSI within 90 days of procedure were included. Patients who received cefazolin were compared to patients who received both cefazolin and vancomycin for CT surgery prophylaxis. The primary outcome was incidence of SSIs within 90 days of surgery as defined by the Centers for Disease Control and National Healthcare Safety Network.

Results

Out of 828 patients who underwent CT surgeries, there were 32 patients readmitted within 90 days for SSI. SSI occurred in 4.7% of patients who received cefazolin monotherapy, and 2.4% of patients who received both cefazolin and vancomycin (p=0.095). There was no discernible difference in types of SSI between groups. Pathogens were isolated in 78% of SSIs, with 75% Gram-positive and 19% Gram-negative organisms. SSIs resulted in an average 9.8 days in the hospital and 28.9 days of antibiotic therapy, and led to a total of 15 additional procedures.

Conclusion

Vancomycin added to cefazolin for prophylaxis in CT surgery resulted in lower incidence of SSI, however the difference was not statistically significant.

Disclosures

All Authors: No reported disclosures

Single cell RNA sequencing identifies transcriptional signature of atherosusceptible endothelium of aorta in diabetes associated atherosclerosis

Background

Transcriptomic analyses have provided invaluable information for linking genotypes to phenotypes. However, despite the near identical genotype, each cell types in our body has a unique gene expression signature. Deep sequencing at single cell resolution has provided a unique opportunity to unbiasedly discover cellular heterogeneity, disease associated cell populations and to characterise the cell specific transcriptomic landscape. Cardiovascular (CV) disease, a leading cause of death worldwide, is caused mainly by atherosclerosis, a pathological build-up of plaque within arterial vessel walls. Fluid mechanical forces generated by disturbed blood flow are long known to cause structural and transcriptional changes in the vascular endothelium. Atherosclerosis develops near branches and bends of arteries exposed to disturbed blood flow. Diabetes accelerates atherosclerosis development and indeed, represents an independent risk factor. However, the transcriptional signature of atheroprone endothelium in the diabetic aorta has not been investigated previously for this CV complication.

Purpose

This study was designed to apply a single cell RNA sequencing (scRNA-seq) approach to identify the transcriptional signature of atherosusceptible endothelium in diabetes associated atherosclerosis.

Methods

Diabetes was induced with streptozotocin in ApoEs−/− mice and followed for 10 weeks. Cells from digested aortae of control and diabetic mice were FACS-sorted for viable and metabolically active cells. These cells were loaded onto the Chromium Single Cell Controller (10X Genomics) to generate a single cell and gel bead emulsion. ScRNA-seq libraries were prepared with Single Cell 3' Solution V2 kit (10X Genomics) and sequenced with Illumina Nova-seq 6000. We have applied scRNA-seq to identify atheroprone endothelial cells in the aorta.

Results and conclusion

The atheroprone endothelial cells show distinct transcriptional profile with more than six hundred genes differentially expressed. ScRNA-seq allowed us not only to distinguish the two transcriptionally distinct endothelial subpopulations but also to identify a diabetes associated gene expression signature unique to atheroprone endothelial cells as compared to all other cell types in the aorta. We identified seventeen genes uniquely dysregulated in the diabetic atheroprone endothelial cell (Cut off = FDR s&lt;0.05, Fold change at least 2-fold). This includes Protein C receptor (Procr) which has recently been identified as a marker for blood vascular endothelial stem cells (VESCs). Downregulation of Procr in the atheroprone endothelial cells of diabetic aorta as identified in our scRNA-seq data indicates that diabetes may limit the vascular repair by targeting VESCs thus contributing to accelerated atherosclerosis. These exciting novel findings have uncovered the transcriptomic landscape of atherosusceptible endothelium of aorta at the single cell level as seen in diabetes associated atherosclerosis.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Heart Foundation of Australia; NHMRC National Health and Medical Research Council of Australia

Metabolomics and a breath sensor identify acetone as a biomarker for heart failure

Introduction

Metabolomics delivers more biological and clinical insight than targeted investigations. We applied metabolomics to patients with heart failure (HF) with reduced ejection fraction (HFrEF).

Methods

46 patients with HFrEF and 20 controls underwent metabolomic profiling, including liquid/gas chromatography mass spectrometry (LC-MS/GC-MS), nuclear magnetic resonance (NMR) metabolomics and solid-phase microextraction (SPME) volatilomics in plasma and urine. HFrEF was defined using left ventricular global longitudal strain (GLS) &lt;18%, ejection fraction &lt;50% and NTproBNP ≥35 pmol/L. A low cost consumer breath acetone (BrACE) sensor validated SPME results in 69 patients.

Results

34 metabolites were identified by GCMS, 33 by LCMS and 2 volatiles by SPME (acetone, 2-pentanone in plasma and urine). Alanine, aspartate and glutamate, citric acid cycle, arginine biosynthesis, glyoxylate and dicarboxylate metabolism were altered in HFrEF. Plasma acetone correlated with NT-proBNP (r=0.59, 95% CI 0.4 to 0.7), triacylglycerol (55:9), 2-oxovaleric and cis-aconitic acid, involved with ketone metabolism and mitochondrial energetics. BrACE &gt;1.5 ppm discriminated HF from other cardiac pathology (AUC 0.88, 95% CI 0.77 to 0.99, P&lt;0.0001).

Conclusion

Breath acetone was detectable in HFrEF patients using a consumer sensor ($1/test) and although not cardiac specific, discriminated HF from other cardiac pathology.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Health Research Council of New Zealand

A qualitative study on mental health and wellbeing of Syrian refugees in the UK

Background

The Syrian conflict has resulted in an estimated 5.3 million registered Syrian refugees in various parts of the world. Evidence suggests that these individuals are at considerable risk of developing common mental disorders. This study aimed to explore the mental wellbeing of Syrian refugees, identify their coping mechanisms and pathways towards integration into new communities, and formulate recommendations for better access to mental healthcare services.

Methods

We conducted a qualitative study using in-depth semi-structured interviews with adult refugees (&gt;18 years old) who are currently residing in Southeast of England. Interviews were conducted in Arabic, recorded, transcribed and translated verbatim. Translated transcripts were analysed using thematic analysis. Ethical Approval was obtained from the Brighton and Sussex Medical School Research Governance Ethics Committee (ER/BSMS9DAP/1).

Results

Twelve participants (3 females and 9 males) took part in the study; all were born in Syria and the majority (n = 9) were over 45 years of age. Participants described symptoms of reduced psychological wellbeing. Preliminary findings shows that almost all participants talked about psychological distress resulting from previous trauma, loss of and separation from family members and challenges adjusting to their host country. Barriers to accessing the healthcare system in the UK included fear of stigma, being misunderstood by healthcare staff and language issues. Communicating with loved ones, connecting with nature, practising faith and pursuing hobbies were reported as coping strategies.

Conclusions

For Syrian refugees in the UK, mental wellbeing embraces living with past traumatic experiences, achieving social integration and facing challenges accessing healthcare. Understanding differences between refugee and host communities is key to appropriately cater to the specific needs of each community and achieve equity in healthcare access.

Key messages

Syrian refugees in UK described symptoms of reduced psychological wellbeing. Understanding the needs of refugee communities is necessary to achieve equity in healthcare access.

Cross-sectional study of the prevalence, causes and management of hospital-onset diarrhoea

BACKGROUND

The National Health Service in England advises hospitals collect data on hospital-onset diarrhoea (HOD). Contemporaneous data on HOD are lacking.

AIM

To investigate prevalence, aetiology and management of HOD on medical, surgical and elderly-care wards.

METHODS

A cross-sectional study in a volunteer sample of UK hospitals, which collected data on one winter and one summer day in 2016. Patients admitted ≥72 h were screened for HOD (definition: ≥2 episodes of Bristol Stool Type 5-7 the day before the study, with diarrhoea onset >48 h after admission). Data on HOD aetiology and management were collected prospectively.

FINDINGS

Data were collected on 141 wards in 32 hospitals (16 acute, 16 teaching). Point-prevalence of HOD was 4.5% (230/5142 patients; 95% confidence interval (CI) 3.9-5.0%). Teaching hospital HOD prevalence (5.9%, 95% CI 5.1-6.9%) was twice that of acute hospitals (2.8%, 95% CI 2.1-3.5%; odds ratio 2.2, 95% CI 1.7-3.0). At least one potential cause was identified in 222/230 patients (97%): 107 (47%) had a relevant underlying condition, 125 (54%) were taking antimicrobials, and 195 (85%) other medication known to cause diarrhoea. Nine of 75 tested patients were Clostridium difficile toxin positive (4%). Eighty (35%) patients had a documented medical assessment of diarrhoea. Documentation of HOD in medical notes correlated with testing for C. difficile (78% of those tested vs 38% not tested, P<0.001). One-hundred and forty-four (63%) patients were not isolated following diarrhoea onset.

CONCLUSION

HOD is a prevalent symptom affecting thousands of patients across the UK health system each day. Most patients had multiple potential causes of HOD, mainly iatrogenic, but only a third had medical assessment. Most were not tested for C. difficile and were not isolated.

Tuberculosis in the Circumpolar Region, 2006-2012

SETTING

The northern circumpolar jurisdictions Canada (Northwest Territories, Nunavik, Nunavut, Yukon), Finland, Greenland, Norway, Russian Federation (Arkhangelsk), Sweden and the United States (Alaska).

OBJECTIVE

To describe and compare demographic, clinical and laboratory characteristics, including drug resistance and treatment completion, of tuberculosis (TB) cases in the northern circumpolar populations.

DESIGN

Descriptive analysis of all active TB cases reported from 2006 to 2012 for incidence rate (IR), age and sex distribution, sputum smear and diagnostic site characteristics, drug resistance and treatment completion rates.

RESULTS

The annual IR of TB disease ranged from a low of 4.3 per 100 000 population in Northern Sweden to a high of 199.5/100 000 in Nunavik, QC, Canada. For all jurisdictions, IR was higher for males than for females. Yukon had the highest proportion of new cases compared with retreatment cases (96.6%). Alaska reported the highest percentage of laboratory-confirmed cases (87.4%). Smear-positive pulmonary cases ranged from 25.8% to 65.2%. Multidrug-resistant cases ranged from 0% (Northern Canada) to 46.3% (Arkhangelsk). Treatment outcome data, available up to 2011, demonstrated >80% treatment completion for four of the 10 jurisdictions.

CONCLUSION

TB remains a serious public health issue in the circumpolar regions. Surveillance data contribute toward a better understanding and improved control of TB in the north.

Can We Accurately Predict Cost Effectiveness Without Access to Overall Survival Data? The Case Study of Nivolumab in Combination with Ipilimumab for the Treatment of Patients with Advanced Melanoma in England

BACKGROUND

Nivolumab with ipilimumab (the Regimen) is the first immuno-oncology combination treatment to demonstrate long-term clinical benefit for advanced melanoma patients. We evaluated the cost effectiveness of the Regimen in this population, with and without the availability of overall survival (OS) data.

METHODS

A partitioned survival model and a Markov state-transition model were developed to estimate the lifetime costs and benefits of the Regimen versus ipilimumab. These models were built with and without the availability of OS data, as only progression-free survival data were available from the head-to-head, phase III trial against ipilimumab at the time of the National Institute for Health and Care Excellence (NICE) submission. Patient utilities and resource use data were sourced from trial data or the literature.

RESULTS

Incremental cost-effectiveness ratios (ICERs) and absolute costs were similar between the models with and without OS data, but the model with OS data generated more than 1 additional quality-adjusted life-year (QALY) across both treatment arms. In both models, based on list prices, the Regimen was the most cost-effective treatment.

CONCLUSIONS

The analyses show that the Regimen is a cost-effective treatment for advanced melanoma patients in England, and methods to overcome the lack of OS can give reasonable estimates of QALYs gained and ICERs.

Correction to: Can We Accurately Predict Cost Effectiveness Without Access to Overall Survival Data? The Case Study of Nivolumab in Combination with Ipilimumab for the Treatment of Patients with Advanced Melanoma in England

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Saxitoxin Exposure Confirmed by Human Urine and Food Analysis

A case of an elderly female with suspected paralytic shellfish poisoning (PSP) is presented. The patient shared a meal of recreationally-harvested shellfish with her family and soon began to experience nausea and weakness. She was taken to the local emergency department and then transported to a larger hospital in Anchorage where she was admitted to the intensive care unit with respiratory depression and shock. Her condition improved, and she was discharged from the hospital 6 days later. No others who shared the meal reported symptoms of PSP. A clam remaining from the meal was collected and analyzed for paralytic shellfish toxins (PST) by the Alaska Department of Environmental Conservation Environmental Health Laboratory; the clam tested positive for saxitoxin (STX; 277 μg/100 g), neosaxitoxin (NEO; 309 μg/100 g), multiple gonyautoxins (GTX; 576-2490 μg/100 g), decarbamoyl congeners (7.52-11.3 μg/100 g) and C-toxins (10.8-221 μg/100 g) using high-pressure liquid chromatography with post-column oxidation (AOAC Method 2011.02). Urine from the patient was submitted to Centers for Disease Control for analysis of selected PSTs and creatinine. STX (64.0 μg/g-creatinine), NEO (60.0 μg/g-creatinine) and GTX1-4 (492-4780 μg/g-creatinine) were identified in the urine using online solid phase extraction with HPLC and tandem mass spectrometry. This was the first time GTX were identified in urine of a PSP case from Alaska, highlighting the need to include all STX congeners in testing to protect the public's health through a better understand of PST toxicity, monitoring and prevention of exposures.

Platelet packing density is an independent regulator of the hemostatic response to injury

Essentials Platelet packing density in a hemostatic plug limits molecular movement to diffusion. A diffusion-dependent steep thrombin gradient forms radiating outwards from the injury site. Clot retraction affects the steepness of the gradient by increasing platelet packing density. Together, these effects promote hemostatic plug core formation and inhibit unnecessary growth.

SUMMARY

Background Hemostasis studies performed in vivo have shown that hemostatic plugs formed after penetrating injuries are characterized by a core of highly activated, densely packed platelets near the injury site, covered by a shell of less activated and loosely packed platelets. Thrombin production occurs near the injury site, further activating platelets and starting the process of platelet mass retraction. Tightening of interplatelet gaps may then prevent the escape and exchange of solutes. Objectives To reconstruct the hemostatic plug macro- and micro-architecture and examine how platelet mass contraction regulates solute transport and solute concentration in the gaps between platelets. Methods Our approach consisted of three parts. First, platelet aggregates formed in vitro under flow were analyzed using scanning electron microscopy to extract data on porosity and gap size distribution. Second, a three-dimensional (3-D) model was constructed with features matching the platelet aggregates formed in vitro. Finally, the 3-D model was integrated with volume and morphology measurements of hemostatic plugs formed in vivo to determine how solutes move within the platelet plug microenvironment. Results The results show that the hemostatic mass is characterized by extremely narrow gaps, porosity values even smaller than previously estimated and stagnant plasma velocity. Importantly, the concentration of a chemical species released within the platelet mass increases as the gaps between platelets shrink. Conclusions Platelet mass retraction provides a physical mechanism to establish steep chemical concentration gradients that determine the extent of platelet activation and account for the core-and-shell architecture observed in vivo.

The Incremental Cost of Incompatible Living Donor Kidney Transplantation: A National Cohort Analysis

Incompatible living donor kidney transplantation (ILDKT) has been established as an effective option for end-stage renal disease patients with willing but HLA-incompatible living donors, reducing mortality and improving quality of life. Depending on antibody titer, ILDKT can require highly resource-intensive procedures, including intravenous immunoglobulin, plasma exchange, and/or cell-depleting antibody treatment, as well as protocol biopsies and donor-specific antibody testing. This study sought to compare the cost and Medicare reimbursement, exclusive of organ acquisition payment, for ILDKT (n = 926) with varying antibody titers to matched compatible transplants (n = 2762) performed between 2002 and 2011. Data were assembled from a national cohort study of ILDKT and a unique data set linking hospital cost accounting data and Medicare claims. ILDKT was more expensive than matched compatible transplantation, ranging from 20% higher adjusted costs for positive on Luminex assay but negative flow cytometric crossmatch, 26% higher for positive flow cytometric crossmatch but negative cytotoxic crossmatch, and 39% higher for positive cytotoxic crossmatch (p < 0.0001 for all). ILDKT was associated with longer median length of stay (12.9 vs. 7.8 days), higher Medicare payments ($91 330 vs. $63 782 p < 0.0001), and greater outlier payments. In conclusion, ILDKT increases the cost of and payments for kidney transplantation.

International validation of the European Organisation for Research and Treatment of Cancer QLQ-BRECON23 quality-of-life questionnaire for women undergoing breast reconstruction

Background

The aim was to carry out phase 4 international field-testing of the European Organisation for Research and Treatment of Cancer (EORTC) breast reconstruction (BRECON) module. The primary objective was finalization of its scale structure. Secondary objectives were evaluation of its reliability, validity, responsiveness, acceptability and interpretability in patients with breast cancer undergoing mastectomy and reconstruction.

Methods

The EORTC module development guidelines were followed. Patients were recruited from 28 centres in seven countries. A prospective cohort completed the QLQ-BRECON15 before mastectomy and the QLQ-BRECON24 at 4–8 months after reconstruction. The cross-sectional cohort completed the QLQ-BRECON24 at 1–5 years after reconstruction, and repeated this 2–8 weeks later (test–retest reliability). All participants completed debriefing questionnaires.

Results

A total of 438 patients were recruited, 234 in the prospective cohort and 204 in the cross-sectional cohort. A total of 414 reconstructions were immediate, with a comparable number of implants (176) and donor-site flaps (166). Control groups comprised patients who underwent two-stage implant procedures (72, 75 per cent) or delayed reconstruction (24, 25 per cent). Psychometric scale validity was supported by moderate to high item-own scale and item-total correlations (over 0·5). Questionnaire validity was confirmed by good scale-to-sample targeting, and computable scale scores exceeding 50 per cent, except nipple cosmesis (over 40 per cent). In known-group comparisons, QLQ-BRECON24 scales and items differentiated between patient groups defined by clinical criteria, such as type and timing of reconstruction, postmastectomy radiotherapy and surgical complications, with moderate effect sizes. Prospectively, sexuality and surgical side-effects scales showed significant responsiveness over time (P &lt; 0·001). Scale reliability was supported by high Cronbach's α coefficients (over 0·7) and test–retest (intraclass correlation more than 0·8). One item (finding a well fitting bra) was excluded based on high floor/ceiling effects, poor test–retest and weak correlations in factor analysis (below 0·3), thus generating the QLQ-BRECON23 questionnaire.

Conclusion

The QLQ-BRECON23 is an internationally validated tool to be used alongside the EORTC QLQ-C30 (cancer) and QLQ-BR23 (breast cancer) questionnaires for evaluating quality of life and satisfaction after breast reconstruction.

Position statement on radiopharmaceutical production for clinical trials

The EU regulation 536/2014 aims to facilitate the experimental use of diagnostic radiopharmaceuticals in particular for GMP requirements and needs to be applied in EU countries. As definitely clarified by this survey, the application is still far from being completed due to national restrictions that are conflicting with the content of the above EU regulation. Although the nuclear medicine centers are obliged to be compliant with national regulatory, national authorities have to be required to work towards full application of the regulation. On the other hand, an update of 536/2014 that includes therapeutic radiopharmaceuticals would also be beneficial to a rational and safe advance of nuclear medicine.

Investigating the genetic underpinnings of early-life irritability

Severe irritability is one of the commonest reasons prompting referral to mental health services. It is frequently seen in neurodevelopmental disorders that manifest early in development, especially attention-deficit/hyperactivity disorder (ADHD). However, irritability can also be conceptualized as a mood problem because of its links with anxiety/depressive disorders; notably DSM-5 currently classifies severe, childhood-onset irritability as a mood disorder. Investigations into the genetic nature of irritability are lacking although twin studies suggest it shares genetic risks with both ADHD and depression. We investigated the genetic underpinnings of irritability using a molecular genetic approach, testing the hypothesis that early irritability (in childhood/adolescence) is associated with genetic risk for ADHD, as indexed by polygenic risk scores (PRS). As a secondary aim we investigated associations between irritability and PRS for major depressive disorder (MDD). Three UK samples were utilized: two longitudinal population-based cohorts with irritability data from childhood (7 years) to adolescence (15-16 years), and one ADHD patient sample (6-18 years). Irritability was defined using parent reports. PRS were derived from large genome-wide association meta-analyses. We observed associations between ADHD PRS and early irritability in our clinical ADHD sample and one of the population samples. This suggests that early irritability traits share genetic risk with ADHD in the general population and are a marker of higher genetic loading in individuals with an ADHD diagnosis. Associations with MDD PRS were not observed. This suggests that early-onset irritability could be conceptualized as a neurodevelopmental difficulty, behaving more like disorders such as ADHD than mood disorders.

Variants on chromosome 4q21 near PKD2 and SIBLINGs are associated with dental caries

A recent genome-wide association study for dental caries nominated the chromosomal region 4q21 near ABCG2, PKD2 and the SIBLING gene family. In this investigation we followed-up and fine-mapped this region using a tag-SNP (single nucleotide polymorphism) approach in 13 age- and race-stratified samples from 6 independent studies (N=4,089). Participants were assessed for dental caries via intra-oral examination and 49 tag-SNPs were genotyped capturing much of the variation in the 4q21 locus. Linear models were used to test for genetic association, while adjusting for sex, age, and components of ancestry. SNPs in and near PKD2 showed significant evidence of association in individual samples of black adults (rs17013735, p-value=0.0009) and white adults (rs11938025; p-value=0.0005; rs2725270, p-value=0.003). Meta-analyses across black adult samples recapitulated the association with rs17013735 (p-value=0.003), which occurs at low frequency in non-African populations, possibly explaining the race-specificity of the effect. In addition to race-specific associations, we also observed evidence of gene-by-fluoride exposure interaction effects in white adults for SNP rs2725233 upstream of PKD2 (p=0.002). Our results show evidence of regional replication, though no single variant clearly accounted for the original GWAS signal. Therefore, while we interpret our results as strengthening the hypothesis that chromosome 4q21 may impact dental caries, additional work is needed.

Acute adrenal insufficiency: an aide-memoire of the critical importance of its recognition and prevention

Adrenal crisis is a life-threatening emergency that causes significant excess mortality in patients with adrenal insufficiency. Delayed recognition by medical staff of an impending adrenal crisis and failure to give timely hydrocortisone therapy within the emergency department continue to be commonly encountered, even in metropolitan teaching hospitals. Within the authors' institutions, several cases of poorly handled adrenal crises have occurred over the last 2 years. Anecdotal accounts from members of the Addison's support group suggest that these issues are common in Australia. This manuscript is a timely reminder for clinical staff on the critical importance of the recognition, treatment and prevention of adrenal crisis. The manuscript: (i) outlines a case and the clinical outcome of sub-optimally managed adrenal crisis, (ii) summarises the clinical features and acute management of adrenal crisis, (iii) provides recommendations on the prevention of adrenal crisis and (iv) provides guidance on the management of 'sick days' in patients with adrenal insufficiency.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Health literacy, literacy, numeracy and nutrition label understanding and use: a scoping review of the literature

BACKGROUND

Low health literacy, literacy and numeracy have been identified as barriers to consumer understanding and the interpretation of nutrition-related information. To inform policy and dietetic practice, we examined the extent, range and nature of research on empirical relationships between health literacy, literacy or numeracy and the understanding and use of nutrition labels.

METHODS

A scoping review of the literature was conducted. A search of eight databases on 15 April 2014 and 26 May 2016 returned 651 and 173 records, respectively. After de-duplication and two levels of relevance screening, 16 studies were deemed eligible for inclusion in the present review.

RESULTS

The majority of studies were conducted in the USA and focused primarily on the use of back-of-pack nutrition labels. Empirical relationships reported between health literacy and nutrition label use were inconsistent and, in some cases, contradictory. The findings from studies examining empirical relationships between literacy, numeracy and nutrition label use suggest that consumers with lower literacy and numeracy: (i) differ from those with higher levels in some of the judgements that they make about food and (ii) may benefit from interventions designed to improve their understanding and use of nutrition label information. Measurement-related issues were identified, such as a reliance on self-reports of nutrition label use, as well as a lack of independence between some measures of health literacy and nutrition label understanding and use.

CONCLUSIONS

The empirical relationships between health literacy, literacy, numeracy and nutrition label understanding and use have not been well-studied. Additional attention is needed regarding the measurement-related issues identified in the present review.

Training Teachers to Maximize Instructional Time Provided to Severely and Profoundly Handicapped Children

Observations affirming the considerable time required for caretaking in classrooms for the severely and profoundly handicapped led to the development of a teacher-training module with the objective of maximizing instructional time. With a minimum of direct training focused on integrating instruction with caretaking, student teachers were able to significantly increase the amount of daily instruction. The importance of quantity of schooling as a critical education variable is discussed.

Combined Carotid Endarterectomy and Vertebral Transposition or Bypass for Cerebral and Vertebrobasilar Insufficiency

The purpose of this report is to determine the indication for a combined carotid endarterectomy and vertebral transposition or bypass in patients who have transient ischemic attack (TIA) or stroke and intractable vertebral ischemic symptoms of dizziness and syncope. A retrospective review was made on 49 patients with the combined symptoms of generalized global ischemia, TIA, amaurosis fugax or stroke, and vertebral basilar insufficiency manifested as syncope, intractable dizziness, and unsteady gait. Diagnostic studies employed were carotid duplex scan, computed tomography (CT) or magnetic resonance imaging (MRI) brain scan, xenon blood flow study, transcranial Doppler analysis, electronystagmography, electroencephalography, and cardiac arrhythmia evaluation. Twenty-one of 49 patients (43%) with internal carotid occlusion underwent carotid endarterectomy plus vein patch or internal carotid to external carotid onlay patch angioplasty and proximal vertebral to common carotid artery transposition (n: 19), or bypass (n:2). Twenty-seven of 49 patients (57%) received carotid endarterec tomy and vertebral transposition (n:27) or bypass (n:2) for carotid and vertebral stenosis. There was no operative mortality, stroke, or neurologic deficit following the carotid and vertebral operations in the 49 patients. Six patients had transient palpebral ptosis. Postoperative cerebral angiogram or magnetic resonance angiogram showed patent vertebral arteries. All 49 patients have resolution of TIA, dizziness, syncope, and unsteady gait. Combined carotid endarterectomy and vertebral transposition or bypass should be considered in patients with solitary, dominant, or bilateral vertebral artery critical stenosis whose symptoms are unrelated to vestibular, cardiac, or seizure disorders and lateralized TIA or stroke.