Spontaneous Coronary Artery Dissection (SCAD) in an Atypical Patient Without Risk Factors and Prior Asymptomatic COVID-19 Infection.

Spontaneous coronary artery dissection (SCAD) is a condition primarily seen in young women and is characterized by non-atherosclerotic arterial damage. It can occur with or without conventional risk factors for coronary heart disease and is often associated with chronic inflammatory conditions. Here, we present a unique instance of a 67-year-old woman without known risk factors who developed sudden onset chest pain in the setting of an asymptomatic coronavirus 2019 (COVID-19) infection three weeks earlier. Subsequent evaluation revealed SCAD in the distal left anterior descending (LAD) artery.

Impact of a phage cocktail targeting Escherichia coli and Enterococcus faecalis as members of a gut bacterial consortium in vitro and in vivo.

Escherichia coli and Enterococcus faecalis have been implicated as important players in human gut health that have been associated with the onset of inflammatory bowel disease (IBD). Bacteriophage (phage) therapy has been used for decades to target pathogens as an alternative to antibiotics, but the ability of phage to shape complex bacterial consortia in the lower gastrointestinal tract is not clearly understood. We administered a cocktail of six phages (either viable or heat-inactivated) targeting pro-inflammatory Escherichia coli LF82 and Enterococcus faecalis OG1RF as members of a defined community in both a continuous fermenter and a murine colitis model. The two target strains were members of a six species simplified human microbiome consortium (SIHUMI-6). In a 72-h continuous fermentation, the phage cocktail caused a 1.1 and 1.5 log (log10 genome copies/mL) reduction in E. faecalis and E. coli numbers, respectively. This interaction was accompanied by changes in the numbers of other SIHUMI-6 members, with an increase of Lactiplantibacillus plantarum (1.7 log) and Faecalibacterium prausnitzii (1.8 log). However, in germ-free mice colonized by the same bacterial consortium, the same phage cocktail administered twice a week over nine weeks did not cause a significant reduction of the target strains. Mice treated with active or inactive phage had similar levels of pro-inflammatory cytokines (IFN-y/IL12p40) in unstimulated colorectal colonic strip cultures. However, histology scores of the murine lower GIT (cecum and distal colon) were lower in the viable phage-treated mice, suggesting that the phage cocktail did influence the functionality of the SIHUMI-6 consortium. For this study, we conclude that the observed potential of phages to reduce host populations in in vitro models did not translate to a similar outcome in an in vivo setting, with this effect likely brought about by the reduction of phage numbers during transit of the mouse GIT.

A completely precious metal-free alkaline fuel cell with enhanced performance using a carbon-coated nickel anode.

SignificanceWe present a groundbreaking advance in completely nonprecious hydrogen fuel cell technologies achieving a record power density of 200 mW/cm2 with Ni@CNx anode and Co-Mn cathode. The 2-nm CNx coating weakens the O-binding energy, which effectively mitigates the undesirable surface oxidation during hydrogen oxidation reaction (HOR) polarization, leading to a stable fuel cell operation for Ni@CNx over 100 h at 200 mA/cm2, superior to a Ni nanoparticle counterpart. Ni@CNx exhibited a dramatically enhanced tolerance to CO relative to Pt/C, enabling the use of hydrogen gas with trace amounts of CO, critical for practical applications. The complete removal of precious metals in fuel cells lowers the catalyst cost to virtually negligible levels and marks a milestone for practical alkaline fuel cells.

Electrocatalysis in Alkaline Media and Alkaline Membrane-Based Energy Technologies.

Hydrogen energy-based electrochemical energy conversion technologies offer the promise of enabling a transition of the global energy landscape from fossil fuels to renewable energy. Here, we present a comprehensive review of the fundamentals of electrocatalysis in alkaline media and applications in alkaline-based energy technologies, particularly alkaline fuel cells and water electrolyzers. Anion exchange (alkaline) membrane fuel cells (AEMFCs) enable the use of nonprecious electrocatalysts for the sluggish oxygen reduction reaction (ORR), relative to proton exchange membrane fuel cells (PEMFCs), which require Pt-based electrocatalysts. However, the hydrogen oxidation reaction (HOR) kinetics is significantly slower in alkaline media than in acidic media. Understanding these phenomena requires applying theoretical and experimental methods to unravel molecular-level thermodynamics and kinetics of hydrogen and oxygen electrocatalysis and, particularly, the proton-coupled electron transfer (PCET) process that takes place in a proton-deficient alkaline media. Extensive electrochemical and spectroscopic studies, on single-crystal Pt and metal oxides, have contributed to the development of activity descriptors, as well as the identification of the nature of active sites, and the rate-determining steps of the HOR and ORR. Among these, the structure and reactivity of interfacial water serve as key potential and pH-dependent kinetic factors that are helping elucidate the origins of the HOR and ORR activity differences in acids and bases. Additionally, deliberately modulating and controlling catalyst-support interactions have provided valuable insights for enhancing catalyst accessibility and durability during operation. The design and synthesis of highly conductive and durable alkaline membranes/ionomers have enabled AEMFCs to reach initial performance metrics equal to or higher than those of PEMFCs. We emphasize the importance of using membrane electrode assemblies (MEAs) to integrate the often separately pursued/optimized electrocatalyst/support and membranes/ionomer components. Operando/in situ methods, at multiscales, and ab initio simulations provide a mechanistic understanding of electron, ion, and mass transport at catalyst/ionomer/membrane interfaces and the necessary guidance to achieve fuel cell operation in air over thousands of hours. We hope that this Review will serve as a roadmap for advancing the scientific understanding of the fundamental factors governing electrochemical energy conversion in alkaline media with the ultimate goal of achieving ultralow Pt or precious-metal-free high-performance and durable alkaline fuel cells and related technologies.

A Case of High-Output Heart Failure.

CASE PRESENTATION: A 55-year-old woman with a medical history of hereditary hemorrhagic telangiectasia (HHT) complicated by recurrent nosebleeds, severe blood loss anemia, hepatic arterial-venous malformation (AVM), pulmonary hypertension, and severe tricuspid regurgitation presented to the HHT specialty clinic with acute hypoxic respiratory failure (new 3-L O2 requirement), weight gain, and volume overload. She was directly admitted to the pulmonary hypertension unit of our hospital. She had two recent admissions for similar symptoms thought to be due to worsening pulmonary arterial hypertension. In prior admissions, she had undergone right heart catheterization demonstrating mild pulmonary hypertension (pulmonary arterial pressure, 29 mm Hg, cardiac output by Fick 5.76, and cardiac index 3.22, mildly elevated pulmonary vascular resistance to 5.5 woods units). She would undergo diuresis with symptomatic improvement; however, after discharge she would rapidly develop recurrent heart failure symptoms. She reported compliance with guideline-directed medications, diuretics, and dietary restrictions and was still suffering severe symptoms. Notably she had previously elevated liver enzymes concerning for cirrhosis and had begun a workup to evaluate for causes of cirrhosis; she had a history of mild alcohol use, negative hepatitis viral serology, and no known history of liver disease.

The Advantages and Challenges of Using Endolysins in a Clinical Setting.

Antibiotic-resistant pathogens are increasingly more prevalent and problematic. Traditional antibiotics are no longer a viable option for dealing with these multidrug-resistant microbes and so new approaches are needed. Bacteriophage-derived proteins such as endolysins could offer one effective solution. Endolysins are bacteriophage-encoded peptidoglycan hydrolases that act to lyse bacterial cells by targeting their cell's wall, particularly in Gram-positive bacteria due to their naturally exposed peptidoglycan layer. These lytic enzymes have received much interest from the scientific community in recent years for their specificity, mode of action, potential for engineering, and lack of resistance mechanisms. Over the past decade, a renewed interest in endolysin therapy has led to a number of successful applications. Recombinant endolysins have been shown to be effective against prominent pathogens such as MRSA, Listeria monocytogenes, Staphylococcus strains in biofilm formation, and Pseudomonas aeruginosa. Endolysins have also been studied in combination with other antimicrobials, giving a synergistic effect. Although endolysin therapy comes with some regulatory and logistical hurdles, the future looks promising, with the emergence of engineered "next-generation" lysins. This review will focus on the likelihood that endolysins will become a viable new antimicrobial therapy and the challenges that may have to be overcome along the way.

Tuberculosis Screening, Testing, and Treatment of US Health Care Personnel: ACOEM and NTCA Joint Task Force on Implementation of the 2019 MMWR Recommendations.

: On May 17, 2019, the US Centers for Disease Control and Prevention and National Tuberculosis Controllers Association issued new Recommendations for Tuberculosis Screening, Testing, and Treatment of Health Care Personnel, United States, 2019, updating the health care personnel-related sections of the Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Health-Care Settings, 2005. This companion document offers the collective effort and experience of occupational health, infectious disease, and public health experts from major academic and public health institutions across the United States and expands on each section of the 2019 recommendations to provide clarifications, explanations, and considerations that go beyond the 2019 recommendations to answer questions that may arise and to offer strategies for implementation.

Anisotropic Synthesis of Armchair Graphene Nanoribbon Arrays from Sub-5 nm Seeds at Variable Pitches on Germanium.

At widths below 10 nm, armchair graphene nanoribbons become semiconductors. One promising route to synthesize nanoribbons is chemical vapor deposition (CVD) of hydrocarbons on Ge(001), and synthesis from seeds reduces nanoribbon polydispersity. In this contribution, we advance the seed-initiated synthesis of nanoribbons and explore the impact of seed size and nanoribbon spacing on growth kinetics. Periodic arrays of graphene seeds are lithographically patterned and etched to reduce their diameter. The viability of initiating synthesis from sub-5 nm seeds is demonstrated, and the pitch between nanoribbons is reduced from 500 to 50 nm to show that crowding effects do not perturb nanoribbon growth kinetics. The invariance of kinetics with pitch in combination with density functional theory (DFT) calculations indicate that (1) the growth species for synthesis has a diffusion length of ≪50 nm and/or (2) the kinetics are strongly attachment-limited. These results demonstrate that seed-initiated synthesis on Ge(001) is a promising route for creating dense arrays of armchair graphene nanoribbons for semiconductor electronics applications.

Alignment of semiconducting graphene nanoribbons on vicinal Ge(001).

Chemical vapor deposition of CH4 on Ge(001) can enable anisotropic growth of narrow, semiconducting graphene nanoribbons with predominately smooth armchair edges and high-performance charge transport properties. However, such nanoribbons are not aligned in one direction but instead grow perpendicularly, which is not optimal for integration into high-performance electronics. Here, it is demonstrated that vicinal Ge(001) substrates can be used to synthesize armchair nanoribbons, of which ∼90% are aligned within ±1.5° perpendicular to the miscut. When the growth rate is slow, graphene crystals evolve as nanoribbons. However, as the growth rate increases, the uphill and downhill crystal edges evolve asymmetrically. This asymmetry is consistent with stronger binding between the downhill edge and the Ge surface, for example due to different edge termination as shown by density functional theory calculations. By tailoring growth rate and time, nanoribbons with sub-10 nm widths that exhibit excellent charge transport characteristics, including simultaneous high on-state conductance of 8.0 µS and a high on/off conductance ratio of 570 in field-effect transistors, are achieved. Large-area alignment of semiconducting ribbons with promising charge transport properties is an important step towards understanding the anisotropic nanoribbon growth and integrating these materials into scalable, future semiconductor technologies.

Genomic Investigation of a Mycobacterium tuberculosis Outbreak Involving Prison and Community Cases in Florida, United States.

We used whole-genome sequencing to investigate a tuberculosis outbreak involving U.S.-born persons in the prison system and both U.S.- and foreign-born persons in the community in Florida over a 7-year period (2009-2015). Genotyping by spacer oligonucleotide typing and 24-locus mycobacterial interspersed repetitive unit-variable number tandem repeat suggested that the outbreak might be clonal in origin. However, contact tracing could not link the two populations. Through a multidisciplinary approach, we showed that the cluster involved distinct bacterial transmission networks segregated by country of birth. The source strain is of foreign origin and circulated in the local Florida community for more than 20 years before introduction into the prison system. We also identified novel transmission links involving foreign and U.S.-born cases not discovered during contact investigation. Our data highlight the potential for spread of strains originating from outside the United States into U.S. "high-risk" populations, such as prisoners, with subsequent movement back to the general community.

Monocyte Function and Clinical Outcomes in Febrile and Afebrile Patients With Severe Sepsis.

INTRODUCTION: Absence of fever is associated with higher mortality in septic patients, but the reason for this is unknown. Immune dysfunction may be a potential link between failure to mount a fever and poor outcomes. The purpose of this study was to evaluate monocyte function and clinical surrogates of immunity (i.e., mortality and acquisition of secondary infections) in febrile and afebrile septic patients. METHODS: Single-center, prospective cohort study of 92 critically ill septic patients. Patients were categorized into febrile (≥38.0°C) and afebrile (<38.0°C) groups based on temperature measurements within 24 hours of sepsis diagnosis. HLA-DR expression and LPS-induced TNF-α production were quantified on days 1-2, days 3-4, and days 6-8 after sepsis diagnosis. A repeated measures mixed models analysis was used to compare these markers between the two groups. RESULTS: Forty-four patients (47.8%) developed a fever within 24 h of sepsis diagnosis. There were no significant differences in HLA-DR expression or LPS-induced TNF-α production between febrile and afebrile patients at any individual time point. However, HLA-DR expression significantly increased between days 1-2 and days 6-8 (median difference 8118 [IQR 1,662, 9,878] antibodies/cell, P = 0.002) in febrile patients, but not in afebrile patients (median difference 403 [-3,382, 3,507] antibodies/cell, P = 0.25). Afebrile patients demonstrated higher 28-day mortality (37.5% vs 18.2%) and increased acquisition of secondary infections (35.4% vs. 15.9%). CONCLUSIONS: Absence of fever is associated with suppressed HLA-DR expression over time, a finding suggestive of monocyte dysfunction in sepsis, as well as worse clinical outcomes.

Antipyretic Therapy in Critically Ill Septic Patients: A Systematic Review and Meta-Analysis.

OBJECTIVE: This meta-analysis aimed to examine the impact of antipyretic therapy on mortality in critically ill septic adults. DATA SOURCES: Literature searches were implemented in Ovid Medline, Embase, Scopus, Cumulative Index of Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, and ClinicalTrials.gov through February 2016. STUDY SELECTION: Inclusion criteria were observational or randomized studies of septic patients, evaluation of antipyretic treatment, mortality reported, and English-language version available. Studies were excluded if they enrolled pediatric patients, patients with neurologic injury, or healthy volunteers. Criteria were applied by two independent reviewers. DATA EXTRACTION: Two reviewers independently extracted data and evaluated methodologic quality. Outcomes included mortality, frequency of shock reversal, acquisition of nosocomial infections, and changes in body temperature, heart rate, and minute ventilation. Randomized and observational studies were analyzed separately. DATA SYNTHESIS: Eight randomized studies (1,507 patients) and eight observational studies (17,432 patients) were analyzed. Antipyretic therapy did not reduce 28-day/hospital mortality in the randomized studies (relative risk, 0.93; 95% CI, 0.77-1.13; I = 0.0%) or observational studies (odds ratio, 0.90; 95% CI, 0.54-1.51; I = 76.1%). Shock reversal (relative risk, 1.13; 95% CI, 0.68-1.90; I = 51.6%) and acquisition of nosocomial infections (relative risk, 1.13; 95% CI, 0.61-2.09; I = 61.0%) were also unchanged. Antipyretic therapy decreased body temperature (mean difference, -0.38°C; 95% CI, -0.63 to -0.13; I = 84.0%), but not heart rate or minute ventilation. CONCLUSIONS: Antipyretic treatment does not significantly improve 28-day/hospital mortality in adult patients with sepsis.

Comparison of monocyte human leukocyte antigen-DR expression and stimulated tumor necrosis factor alpha production as outcome predictors in severe sepsis: a prospective observational study.

BACKGROUND: Identifying patients in the immunosuppressive phase of sepsis is essential for development of immunomodulatory therapies. Little data exists comparing the ability of the two most well-studied markers of sepsis-induced immunosuppression, human leukocyte antigen (HLA)-DR expression and lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-ɑ) production, to predict mortality and morbidity. The purpose of this study was to compare HLA-DR expression and LPS-induced TNF-ɑ production as predictors of 28-day mortality and acquisition of secondary infections in adult septic patients. METHODS: A single-center, prospective observational study of 83 adult septic patients admitted to a medical or surgical intensive care unit. Blood samples were collected at three time points during the septic course (days 1-2, days 3-4, and days 6-8 after sepsis diagnosis) and assayed for HLA-DR expression and LPS-induced TNF-ɑ production. A repeated measures mixed model analysis was used to compare values of these immunological markers among survivors and non-survivors and among those who did and did not develop a secondary infection. RESULTS: Twenty-five patients (30.1 %) died within 28 days of sepsis diagnosis. HLA-DR expression was significantly lower in non-survivors as compared to survivors on days 3-4 (p = 0.04) and days 6-8 (p = 0.002). The change in HLA-DR from days 1-2 to days 6-8 was also lower in non-survivors (p = 0.04). Median HLA-DR expression decreased from days 1-2 to days 3-4 in patients who developed secondary infections while it increased in those without secondary infections (p = 0.054). TNF-ɑ production did not differ between survivors and non-survivors or between patients who did and did not develop a secondary infection. CONCLUSIONS: Monocyte HLA-DR expression may be a more accurate predictor of mortality and acquisition of secondary infections than LPS-stimulated TNF-ɑ production in adult medical and surgical critically ill patients.

Assessing the utility of an online registry for patients monitoring their own warfarin therapy.

AIMS: To evaluate the utility of an online self-report registry for patient self-monitoring and self-management (PSM) of warfarin therapy. METHODS: A prospective observational study of UK-based patients undertaking PSM and recording their international normalised ratio (INR) data via an online registry. Consenting participants recorded INR test dates, results and warfarin dosages using the online registry for a period of 12 months. Participants reported demographic data, disease characteristics and treatment-related adverse events and provided feedback via a survey. Data accuracy was assessed through comparison of INR results recorded online with results stored on 19 INR testing devices. Percentage time spent within therapeutic time in range (TTR) was also examined. RESULTS: Eighty-seven per cent (39/45) completed the study period. Age ranged from 26 to 83 years, 44% had undertaken PSM for >5 years. Sixty-six per cent (25/38) reported that the registry was easy to navigate and use. Forty-two participants contributed a total of 1669 INR results. Agreement between self-reported INR results and source INR data was high (99%). Mean TTR was 76% (SD 18.58) with 83% having >60% TTR. CONCLUSIONS: Findings suggest that an online PSM registry is feasible, accurate and acceptable to patients. These findings require confirmation in a larger cohort of PSM patients. An online self-report registry could provide a valuable resource for gathering real world evidence of clinical effectiveness and safety of these developing models of care.

Controlled delivery of antibodies from injectable hydrogels.

Therapeutic antibodies are currently used for the treatment of various diseases, but large doses delivered systemically are typically required. Localized controlled delivery techniques would afford major benefits such as decreasing side effects and required doses. Injectable biopolymer systems are an attractive solution due to their minimally invasive potential for controlled release in a localized area. Here, alginate-chitosan hydrogels are demonstrated to provide controlled delivery of IgG model antibodies and also of Fab antibody fragments. Also, an alternate delivery system comprised of poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with antibodies and encapsulated in alginate was shown to successfully provide another level of control over release. These biopolymer systems that offer controlled delivery for antibodies and antibody fragments will be promising for many applications in drug delivery and regenerative medicine.

Possible role of the microbiome in the development of acute malnutrition and implications for food-based strategies to prevent and treat acute malnutrition.

A pattern of changes in the microbiome composition have been observed in the normal maturation of the human gut. Perturbations from this pattern have been described in malnourished humans and reproduced in animal models of severe malnutrition. Treatment and prevention of malnutrition in the future may be more effective if the interventions not only restore body composition, but the composition of the microbiome as well.

Extending supplementary feeding for children younger than 5 years with moderate acute malnutrition leads to lower relapse rates.

OBJECTIVES: Children with moderate acute malnutrition (MAM) have a high rate of relapse and death in the year following recovery. In this pilot study, we evaluate the long-term benefits of an extended course of nutritional therapy for children with MAM. METHODS: Rural Malawian children 6 to 59 months old with MAM, defined as a weight-for-height z score (WHZ) between -2 and -3, were provided supplementary feeding for a fixed duration of 12 weeks. The children were then studied for 12 months to assess long-term nutritional status, and compared with children initially treated only until they first reached WHZ > -2. RESULTS: Compared with children treated until they reached WHZ > -2, children treated for 12 weeks were more likely to remain well nourished (71% vs 63%, P = 0.0015) and maintain more normal anthropometric indices during 12 months of follow-up; there was also a trend towards lower rates of severe acute malnutrition (7% vs 10%, P = 0.067) and death (2% vs 4%, P = 0.082). Regression modeling showed that mid-upper arm circumference and WHZ at the end of supplementary feeding were the most important factors in predicting which children remained well nourished (P < 0.001 for each). CONCLUSIONS: The duration of supplementary feeding for children with MAM may not be as important as their anthropometry in terms of remaining well nourished after initial recovery. The presently accepted recovery criteria of WHZ of -2 may be insufficient for ensuring long-term nutritional health; consideration should be given to setting higher recovery criteria.

Home-based therapy for severe acute malnutrition with ready-to-use food.

Severe acute malnutrition is a devastating condition afflicting under-5 children in many developing countries, but concentrated in sub-Saharan Africa. This paper examines the development of home-based lipid-nutrient therapeutic foods for the treatment of acute malnutrition in sub-Saharan Africa and the adoption of these therapies as a standard of care for non-complicated cases of acute malnutrition. Several of the early key clinical and operational effectiveness trials are discussed as well as the adoption of home-based treatment as a standard operating procedure in regions where malnutrition is present.

Zinc or albendazole attenuates the progression of environmental enteropathy: a randomized controlled trial.

BACKGROUND & AIMS: Environmental enteropathy (EE) is a subclinical condition among children in the developing world, characterized by T-cell infiltration of the small-bowel mucosa and diffuse villous atrophy. EE leads to macronutrient and micronutrient malabsorption and stunting, with a resultant increased risk for infection and reduced cognitive development. We tested the hypothesis that zinc and albendazole treatments would reduce the severity of EE in rural African children. METHODS: In a randomized, double-blind, placebo-controlled trial in rural southern Malawi, asymptomatic children, 1 to 3 years old and at high risk for EE, received either a single dose of albendazole, a 14-day course of 20 mg zinc sulfate, or a placebo. Subjects were given the dual-sugar absorption test, and the ratio of lactulose to mannitol (L:M) in urine was used to determine the severity of EE at baseline and 34 days after completion of the assigned regimen. The primary outcome was the change in the L:M. RESULTS: A complete set of urine samples was obtained from 222 of 234 children enrolled and analyzed. The mean baseline L:M was 0.32 ± 0.18 among all children and did not differ among groups (normal L:M range, <0.12). At the end of the study, the L:M ratio had increased more in the placebo group (0.12 ± 0.31) than in the zinc group (0.03 ± 0.20; P < .03) or the albendazole group (0.04 ± 0.22; P < .04). CONCLUSIONS: Treatment with zinc or albendazole protects against a significant increase in the L:M ratio, a biomarker for EE, in asymptomatic rural Malawian children. These findings could provide insight into the etiology and pathogenesis of EE. Clinicaltrials.gov Number: NCT01440608.

ExPeKT--Exploring prevention and knowledge of venous thromboembolism: a two-stage, mixed-method study protocol.

INTRODUCTION: There is little awareness of venous thromboembolism (VTE) in the public arena. Most commonly known causes are-travellers' thrombosis and thrombosis associated with oral contraception, both frequently referred to in the media. However, VTE is a substantial healthcare problem, resulting in mortality, morbidity and economic cost. Most hospitalised patients have one or more risk factors for VTE. Around 60% of people undergoing hip or knee replacement will suffer a deep vein thrombosis without preventative intervention. Studies demonstrate a risk reduction for VTE of up to 70% with preventative medicine for medical and surgical conditions: cancer, orthopaedic surgery, general surgery and acutely ill medical admissions. Results will be used to identify methods of increasing knowledge of VTE prevention and for the development of educational and patient information materials. METHODS AND ANALYSIS: A two-stage, mixed-method study using surveys with primary healthcare professionals and patients followed by interviews with primary healthcare professionals, patients, acute trusts and other relevant organisations. Survey and qualitative interview data will examine the current practice of thromboprophylaxis, and the knowledge and experience of VTE prevention for the development of education initiatives for primary healthcare professionals and patients to adopt thromboprophylaxis outside the hospital setting. As this is a scientific exploratory study for the generation, rather than testing, of new hypotheses a sample-size analysis is not called for. Survey data will be analysed using SPSS version 20. Open-ended responses will be analysed using qualitative thematic methods. The recorded and transcribed semistructured interview data will be analysed using constant comparative methods. ETHICS AND DISSEMINATION: Ethics approval has been provided by the National Research Ethics Committee (reference: 11/H0605/5) and site-specific R&D approval granted by the relevant R&D National Health Service trusts. Findings will be disseminated at healthcare and academic conferences and written for peer-reviewed publication. TRIAL GRANT NUMBER: NIHR RP-PG-0608-10073.