Informing the management of multiple stressors on estuarine ecosystems using an expert-based Bayesian Network model.

The approach of applying stressor load limits or thresholds to aid estuarine management is being explored in many global case studies. However, there is growing concern regarding the influence of multiple stressors and their cumulative effects on the functioning of estuarine ecosystems due to the considerable uncertainty around stressor interactions. Recognising that empirical data limitations hinder parameterisation of detailed models of estuarine ecosystem responses to multiple stressors (suspended sediment, sediment mud and metal content, and nitrogen inputs), an expert driven Bayesian network (BN) was developed and validated. Overall, trends in estuarine condition predicted by the BN model were well supported by field observations, including results that were markedly higher than random (71-84% concordance), providing confidence in the overall model dynamics. The general BN framework was then applied to a case study estuary to demonstrate the model's utility for informing management decisions. Results indicated that reductions in suspended sediment loading were likely to result in improvements in estuarine condition, which was further improved by reductions in sediment mud and metal content, with an increased likelihood of high abundance of ecological communities relative to baseline conditions. Notably, reductions in suspended sediment were also associated with an increased probability of high nuisance macroalgae and phytoplankton if nutrient loading was not also reduced (associated with increased water column light penetration). Our results highlight that if stressor limit setting is to be implemented, limits must incorporate ecosystem responses to cumulative stressors, consider the present and desired future condition of the estuary of interest, and account for the likelihood of unexpected ecological outcomes regardless of whether the experts (or empirical data) suggest a threshold has or has not been triggered.

Patient-reported outcomes of immediate implant-based breast reconstruction with and without biological or synthetic mesh.

BACKGROUND: Biological and synthetic meshes may improve the outcomes of immediate implant-based breast reconstruction (IBBR) by facilitating single-stage procedures and improving cosmesis. Supporting evidence is, however, limited. The aim of this study was to explore the impact of biological and synthetic mesh on patient-reported outcomes (PROs) of IBBR 18 months after surgery. METHODS: Consecutive women undergoing immediate IBBR between February 2014 and June 2016 were recruited to the study. Demographic, operative, oncological and 3-month complication data were collected, and patients received validated BREAST-Q questionnaires at 18 months. The impact of different IBBR techniques on PROs were explored using mixed-effects regression models adjusted for clinically relevant confounders, and including a random effect to account for clustering by centre. RESULTS: A total of 1470 participants consented to receive the questionnaire and 891 completed it. Of these, 67 women underwent two-stage submuscular reconstructions. Some 764 patients had a submuscular reconstruction with biological mesh (495 women), synthetic mesh (95) or dermal sling (174). Fourteen patients had a prepectoral reconstruction. Compared with two-stage submuscular reconstructions, no significant differences in PROs were seen in biological or synthetic mesh-assisted or dermal sling procedures. However, patients undergoing prepectoral IBBR reported better satisfaction with breasts (adjusted mean difference +6.63, 95 per cent c.i. 1.65 to11.61; P = 0.009). PROs were similar to those in the National Mastectomy and Breast Reconstruction Audit 2008-2009 cohort, which included two-stage submuscular procedures only. CONCLUSION: This study found no difference in PROs of subpectoral IBBR with or without biological or synthetic mesh, but provides early data to suggest improved satisfaction with breasts following prepectoral reconstruction. Robust evaluation is required before this approach can be adopted as standard practice.

Experiences of implant loss after immediate implant-based breast reconstruction: qualitative study.

BACKGROUND: Immediate implant-based breast reconstruction (IBBR) is the most commonly performed reconstructive procedure in the UK, but almost one in ten women experience implant loss and reconstructive failure after this technique. Little is known about how implant loss impacts on patients' quality of life. The first phase of the Loss of implant Breast Reconstruction (LiBRA) study aimed to use qualitative methods to explore women's experiences of implant loss and develop recommendations to improve care. METHODS: Semistructured interviews were conducted with a purposive sample of women who experienced implant loss after immediate IBBR, performed for malignancy or risk reduction across six centres. Interviews explored decision-making regarding IBBR, and experiences of implant loss and support received. Thematic analysis was used to explore the qualitative interview data. Sampling, data collection and analysis were undertaken concurrently and iteratively until data saturation was achieved. RESULTS: Twenty-four women were interviewed; 19 had surgery for malignancy and five for risk reduction. The median time between implant loss and interview was 42 (range 22-74) months. Ten women had undergone secondary reconstruction, two were awaiting surgery, and 12 had declined further reconstruction. Three key themes were identified: the need for accurate information about the risks and benefits of IBBR; the need for more information about 'early-warning' signs of postoperative problems, to empower women to seek help; and better support following implant loss. CONCLUSION: Implant loss is a devastating event for many women. Better preoperative information and support, along with holistic patient-centred care when complications occur, may significantly improve the experience and outcome of care.

ANTECEDENTES: La reconstrucción mamaria inmediata con prótesis (implant-based breast reconstruction, IBBR) es el procedimiento reconstructivo más utilizado en el Reino Unido, pero casi una de cada diez mujeres presentará pérdida de la prótesis y fallo del procedimiento reconstructivo tras esta técnica. Se sabe poco de cómo la pérdida de la prótesis afecta la calidad de vida de las pacientes. La primera fase del estudio LiBRA tuvo como objetivo explorar la percepción de las mujeres ante la pérdida de la prótesis, utilizando métodos cualitativos, y proponer una serie de medidas para mejorar la atención sanitaria de estas pacientes. MÉTODOS: Se realizaron entrevistas semiestructuradas en una muestra de mujeres que padecieron la pérdida de la prótesis tras una IBBR inmediata, realizada por neoplasia o como procedimiento de reducción de riesgo, en seis centros. Las entrevistas analizaron la toma de decisiones con respecto a la IBBR inmediata, así como la percepción ante la pérdida del implante y el soporte recibido. Se utilizó un análisis por temas para examinar los datos de la entrevista cualitativa. El muestreo, la recopilación de datos y el análisis se realizaron de forma simultánea e iterativa hasta que se logró la saturación de datos. RESULTADOS: Se entrevistaron 24 pacientes; 19 en las que la indicación quirúrgica fue por cáncer y 5 por reducción de riesgo. La mediana del tiempo entre la pérdida del implante y la entrevista fue de 42 (rango 22-52) meses. Diez mujeres se habían sometido a una reconstrucción secundaria; dos estaban a la espera de la cirugía y 12 habían rechazado la reconstrucción posterior. Se identificaron tres temas clave, siendo las necesidades de: i) información precisa sobre los riesgos y beneficios de la IBBR, ii) más información sobre los signos de "alarma precoz" de las complicaciones postoperatorias que permitiesen a las mujeres buscar ayuda, y iii) mejor soporte tras la pérdida de la prótesis. CONCLUSIÓN: La pérdida de una prótesis es una complicación catastrófica para muchas mujeres. Una mejor información y apoyo preoperatorios, junto con una atención holística centrada en la paciente cuando se presentan las complicaciones, podrían mejorar significativamente la experiencia y el resultado de la atención.

Acellular dermal matrix (ADM) assisted breast reconstruction procedures: joint guidelines from the Association of Breast Surgery and the British Association of Plastic, Reconstructive and Aesthetic Surgeons.

Tissue expansion with delayed insertion of a definitive prosthesis is the most common form of immediate breast reconstruction performed in the United Kingdom. However, achieving total muscle coverage of the implant and natural ptosis is a key technical challenge. The use of acellular dermal matrices (ADM) to supplement the pectoralis major muscle at the lower and lateral aspects of the breast has been widely adopted in the UK, potentially allowing for a single stage procedure. There is however little published data on the clinical and quality criteria for its use, and no long term follow-up. The guidelines have been jointly produced by the Association of Breast Surgery and the British Association of Plastic, Reconstructive and Aesthetic Surgeons and their aims are: to inform those wishing to undertake ADM assisted breast reconstruction and, to identify clinical standards and quality indicators for audit purposes. The guidelines are based on expert opinion of a multi-disciplinary working group, who are experienced in the technique, and a review of the published data.

Interaction networks in coastal soft-sediments highlight the potential for change in ecological resilience.

Recent studies emphasize the role of indirect relationships and feedback loops in maintaining ecosystem resilience. Environmental changes that impact on the organisms involved in these processes have the potential to initiate threshold responses and fundamentally shift the interactions within an ecosystem. However, empirical studies are hindered by the difficulty of designing appropriate manipulative experiments to capture this complexity. Here we employ structural equation modeling to define and test the architecture of ecosystem interaction networks. Using survey data from 19 estuaries we investigate the interactions between biological (abundance of large bioturbating macrofauna, microphytobenthos, and detrital matter) and physical (sediment grain size) processes. We assess the potential for abrupt changes in the architecture of the network and the strength of interactions to occur across environmental gradients. Our analysis identified a potential threshold in the relationship between sediment mud content and benthic chlorophyll a, at -12 microg/g, using quantile regression. Below this threshold, the interaction network involved different variables and fewer feedbacks than above. This approach has potential to improve our empirical understanding of thresholds in ecological systems and our ability to design manipulative experiments that test how and when a threshold will be passed. It can also be used to indicate to resource managers that a particular system has the potential to exhibit threshold responses to environmental change, emphasizing precautionary management and facilitating a better understanding of how persistent multiple stressors threaten the resilience and long-term use of natural ecosystems.

Primary hyperparathyroidism: how many cases are being missed?

INTRODUCTION: Primary hyperparathyroidism (PHPT) is a common condition (250 per million population per year) with significant associated morbidity and mortality. Surgery is the only curative option for PHPT; results from medical treatment remain disappointing. The aim of this study was to evaluate the referral patterns of patients with PHPT and identify the number of missed cases with a biochemical diagnosis of PHPT. MATERIALS AND METHODS: All chemistries for Worcestershire were performed and analysed at the Worcestershire Royal Hospital. Patients with chronic renal failure were identified and excluded. Routes of patient referral were identified and missed cases documented. General practitioners (GPs) were contacted by letter for all patients not referred or treated. Outcomes of diagnosis and specialist assessment were recorded. RESULTS: A total of 102 cases of PHPT were identified: 64 (62.7%) remained untreated and without a specialist referral in place, 36 (35.3%) had undergone parathyroidectomy and 2 (2.0%) were being monitored. The GP response rate was 90% (46/51). Of these, 30 (65%) were subsequently referred, 9 (20%) underwent repeat tests with a view to referral and 7 (15%) were lost to follow up. CONCLUSIONS: A significant proportion of patients with PHPT remain in the community untreated and having not seen a specialist. All patients should be referred to a specialist for assessment and consideration of surgical treatment and follow-up. Improvements in GP education and referral systems are required if patients are to benefit.

Pseudoangiomatous stromal hyperplasia (PASH): a brief review.

Pseudoangiomatous stromal hyperplasia (PASH) is a benign entity of the breast and typically found incidentally. It warrants thorough investigation in order to exclude more sinister pathology masquerading as this form of benign breast disease and can often be managed expectantly without the need for surgical intervention. We provide a brief review of the literature on PASH, discussing its clinicopathological features and management.

Pseudomonal breast infection.

Breast infection and breast sepsis secondary to Pseudomonas aeruginosa is uncommon. We report two cases of pseudomonal breast infection leading to septic shock and abscess formation in women with non-responding breast infection. The management of breast infection is broad-spectrum antibiotics and ultrasound with aspiration of any collection. To treat breast infection effectively, the causative organism must be isolated to enable appropriate antibiotic therapy.

Trophic structure of coastal Antarctic food webs associated with changes in sea ice and food supply.

Predicting the dynamics of ecosystems requires an understanding of how trophic interactions respond to environmental change. In Antarctic marine ecosystems, food web dynamics are inextricably linked to sea ice conditions that affect the nature and magnitude of primary food sources available to higher trophic levels. Recent attention on the changing sea ice conditions in polar seas highlights the need to better understand how marine food webs respond to changes in such broad-scale environmental drivers. This study investigated the importance of sea ice and advected primary food sources to the structure of benthic food webs in coastal Antarctica. We compared the isotopic composition of several seafloor taxa (including primary producers and invertebrates with a variety of feeding modes) that are widely distributed in the Antarctic. We assessed shifts in the trophic role of numerically dominant benthic omnivores at five coastal Ross Sea locations. These locations vary in primary productivity and food availability, due to their different levels of sea ice cover, and proximity to polynyas and advected primary production. The delta15N signatures and isotope mixing model results for the bivalves Laternula elliptica and Adamussium colbecki and the urchin Sterechinus neumeyeri indicate a shift from consumption of a higher proportion of detritus at locations with more permanent sea ice in the south to more freshly produced algal material associated with proximity to ice-free water in the north and east. The detrital pathways utilized by many benthic species may act to dampen the impacts of large seasonal fluctuations in the availability of primary production. The limiting relationship between sea ice distribution and in situ primary productivity emphasizes the role of connectivity and spatial subsidies of organic matter in fueling the food web. Our results begin to provide a basis for predicting how benthic ecosystems will respond to changes in sea ice persistence and extent along environmental gradients in the high Antarctic.

Effective long-term ecological monitoring using spatially and temporally nested sampling.

Effective environmental management requires documentation of ecosystem status and changes to that status. Without long-term data, short-term natural variability can mask chronic and/or cumulative impacts, often until critical levels are reached. However, a trade-off generally occurs between sampling in space and time. This study analyses a spatially and temporally nested long-term (12 years) monitoring programme conducted on benthic macrofauna in a large harbour. Sampling was carried out at six sites for 5.5 years, after which only two sites were sampled for the next 5 years. After this period, all six sites were sampled for another 2 years. While ecology is frequently thought of being highly variable, this design was able to detect trends, and cycles, in abundance, with only around 10% of species at each site exhibiting unpredictable temporal variability. Sites exhibiting similar trends in the abundance of a species over the 12.5-year period were generally spatially contiguous, and the spatial scale of change could be assessed. Continuous sampling at two sites identified whether changes in unsampled sites were related to long-term cycles. Moreover, this sampling provided a long-term background of temporal fluctuations against which to assess the ecological significance of observed changes.

Surgeons' views on multi-disciplinary breast meetings.

The aim of this study was to assess surgeons' views and their current commitments to multi-disciplinary breast meetings (MDMs). Two hundred and fifty questionnaires were sent out to registered members of the British Association of Surgical Oncology. Hundred and fifty-three were returned (reply rate 61.2%), of which 136 were suitable for analysis. All those who replied were involved in MDMs. 80.9% held MDMs once a week. Only 28% of MDMs were held during a protected session. Over 95% of surgeons and breast care nurses were present for the whole meeting. Radiologists and pathologists were present for the whole meeting in 90-95% of cases. In contrast, clinical oncologists were present for the whole MDM in 70% of cases and medical oncologists attended the whole meeting in only 44.1% of cases. There was variability in which patients were discussed in MDMs, and in many centres not all patients with cancer were discussed before surgery. Suggestions for improvement of MDMs included more time on protected sessions (72.8% in favour), time to prepare for meetings (29% in favour), allocation of a designated co-ordinator (30.9% in favour) and attendance of oncologists for the whole meeting (over 35% in favour). The majority of Breast MDMs were held at breakfast, lunch or the evening. There was variable attendance with a significant percentage of both clinical and medical oncologists not being present for the whole meeting. A quarter of units did not discuss patients with breast cancer before operation. This study shows that there is a need to improve provision for MDMs and to produce guidelines for these meetings.

Intra-operative peritoneal lavage--who does it and why?

INTRODUCTION: Intra-operative peritoneal lavage (IOPL) is widely practised but its benefits are unclear. The frequency and pattern of its use amongst general surgeons is investigated. METHODS: A postal questionnaire was sent to 153 general surgical consultants and registrars enquiring about their use of IOPL. The surgeon was asked the volume and type of lavage fluid used, under various circumstances. RESULTS: 118 (77%) questionnaires were returned. 115 (97%) surgeons used IOPL. The majority of surgeons (61%) lavaged until the fluid was clear, 20% used more than 1 l and 17% used between 500-1000 ml. In the case of the dirty abdomen (i.e. gross pus or faecal peritonitis), 47% used saline as the lavage fluid, 38% aqueous betadine, 9% water and 3% antibiotic lavage. Similar results were found in the case of a contaminated abdomen (i.e. a breached hollow viscus). 34% of surgeons used IOPL during clean cases. 36% used water lavage during intra-abdominal cancer surgery; 21% lavaged with saline and 17% with betadine. More registrars (47%) than consultants (29%) lavaged with water during cancer surgery. Consultants, however, used more aqueous betadine. CONCLUSIONS: The frequency of use and choice of lavage fluid varies widely. The successful management of the septic abdomen rests on at least 3 tenants - systemic antibiotics, control of the source of infection and aspiration of gross contaminants. There is little good evidence in the literature to support IOPL in the management of the septic abdomen. The use of IOPL during cancer surgery is supported by in vitro evidence. The current use of IOPL, as shown by this study, appears not to be evidence based.

Does radical surgery to the axilla give a survival advantage in more severe breast cancer?

There is some evidence that more radical treatment of the axilla may improve survival in node-positive disease, but there are concerns about the resultant morbidity from axillary surgery and radiotherapy. The aim of this study was to compare the outcome of axillary node clearance with axillary sampling in similar patients by comparing loco-regional recurrence and overall survival. Patients with invasive breast cancer undergoing axillary surgery between 1986 and 1997 were included. The axillary procedure performed in these patients was either an axillary sample or a level III axillary clearance. To compare like with, the patients were separated into good, moderate and poor prognostic groups by the Nottingham Prognostic Index (NPI) and overall survival was compared by a Kaplan-Meier life table analysis and the log rank test. 734 consecutive patients with operable invasive breast cancer were treated by axillary clearance n=350 or sampling n=384. The mean follow-up in the clearance group was 65 months versus 66 months in the sampled group. Local recurrence in the clearance group was 11% versus 6% in the sampled group, regional recurrence 2% versus 3% and distant metastasis 28% versus 13%. Kaplan-Meier analysis of the three prognostic groups for the clearance versus sampled groups showed no differences in the absolute survival (log rank: P=0.3, P=0.8 and P=0.6 for the good, moderate and poor prognostic groups, respectively). A conservative surgical approach to the axilla did not significantly increase the incidence of local or regional recurrence and the expected survival benefit from a radical axillary clearance was not apparent.

Terrigenous clay deposition on estuarine sandflats: using stable isotopes to determine the role of the mud crab, Helice crassa Dana, in the recovery process.

Clay slurries, mixed in seawater, were deposited on intertidal mudflats in two contrasting estuaries in an experiment designed to evaluate the potential impact of soil erosion from adjacent urban developments on the biodiversity of the benthic communities, and the subsequent recovery mechanisms. Profiles of the natural abundance of stable isotopes from sediment cores where examined to determine immediate and longer-term impacts of the clay on the ambient sediments. The source clays with delta13C values of about -26 per thousand were easily distinguished from natural sediments with delta13C values of -19.7 +/- 1.1 per thousand at site OK and -14.2 +/- 0.9 per thousand at site WP, and bioturbation was seen to generate a gradient between these values. Physical processes of burial, or erosion and dispersal by estuarine flows initiated the recovery process. Repeated drying cycles left the clay surface cracked and able to trap natural sediments and food on the otherwise barren surface. Colonisation of the clay plots by the mud crab, Helice crassa, was important to the recovery process and depended on proximity to adjacent crab colonies. Burrowing activity by larger crabs enhanced the erosion of the clay surface while the resultant bioturbation blended the clay into the underlying sediments. Smaller crabs had less effect on erosion and bioturbation from their burrowing was mostly confined within the clay layer. Where the clay was more than 3 cm thick, they did not break through the bottom of the clay and the interface between clay and sediment was still sharp after 12 months. 13C variations also indicated that crab burrows and cracking of the clay surface moved natural sediment deep into the plots where it could be worked into the clay by subsequent crab burrowing activities thus enhancing recovery from the clay impact.