Placoid scales in bioluminescent sharks: Scaling their evolution using morphology and elemental composition

Elasmobranchs are characterised by the presence of placoid scales on their skin. These scales, structurally homologous to gnathostome teeth, are thought to have various ecological functions related to drag reduction, predator defense or abrasion reduction. Some scales, particularly those present in the ventral area, are also thought to be functionally involved in the transmission of bioluminescent light in deep-sea environments. In the deep parts of the oceans, elasmobranchs are mainly represented by squaliform sharks. This study compares ventral placoid scale morphology and elemental composition of more than thirty deep-sea squaliform species. Scanning Electron Microscopy and Energy Dispersive X-ray spectrometry, associated with morphometric and elemental composition measurements were used to characterise differences among species. A maximum likelihood molecular phylogeny was computed for 43 shark species incuding all known families of Squaliformes. Character mapping was based on this phylogeny to estimate ancestral character states among the squaliform lineages. Our results highlight a conserved and stereotypical elemental composition of the external layer among the examined species. Phosphorus-calcium proportion ratios (Ca/P) slightly vary from 1.8-1.9, and fluorine is typically found in the placoid scale. By contrast, there is striking variation in shape in ventral placoid scales among the investigated families. Character-mapping reconstructions indicated that the shield-shaped placoid scale morphotype is likely to be ancestral among squaliform taxa. The skin surface occupied by scales appears to be reduced in luminous clades which reflects a relationship between scale coverage and the ability to emit light. In luminous species, the placoid scale morphotypes are restricted to pavement, bristle- and spine-shaped except for the only luminescent somniosid, Zameus squamulosus, and the dalatiid Mollisquama mississippiensis. These results, deriving from an unprecedented sampling, show extensive morphological diversity in placoid scale shape but little variation in elemental composition among Squaliformes.publishedVersio

Hospital-level evaluation of the effect of a national quality improvement programme: time-series analysis of registry data.

BACKGROUND AND OBJECTIVES: A clinical trial in 93 National Health Service hospitals evaluated a quality improvement programme for emergency abdominal surgery, designed to improve mortality by improving the patient care pathway. Large variation was observed in implementation approaches, and the main trial result showed no mortality reduction. Our objective therefore was to evaluate whether trial participation led to care pathway implementation and to study the relationship between care pathway implementation and use of six recommended implementation strategies. METHODS: We performed a hospital-level time-series analysis using data from the Enhanced Peri-Operative Care for High-risk patients trial. Care pathway implementation was defined as achievement of >80% median reliability in 10 measured care processes. Mean monthly process performance was plotted on run charts. Process improvement was defined as an observed run chart signal, using probability-based 'shift' and 'runs' rules. A new median performance level was calculated after an observed signal. RESULTS: Of 93 participating hospitals, 80 provided sufficient data for analysis, generating 800 process measure charts from 20 305 patient admissions over 27 months. No hospital reliably implemented all 10 processes. Overall, only 279 of the 800 processes were improved (3 (2-5) per hospital) and 14/80 hospitals improved more than six processes. Mortality risk documented (57/80 (71%)), lactate measurement (42/80 (53%)) and cardiac output guided fluid therapy (32/80 (40%)) were most frequently improved. Consultant-led decision making (14/80 (18%)), consultant review before surgery (17/80 (21%)) and time to surgery (14/80 (18%)) were least frequently improved. In hospitals using ≥5 implementation strategies, 9/30 (30%) hospitals improved ≥6 care processes compared with 0/11 hospitals using ≤2 implementation strategies. CONCLUSION: Only a small number of hospitals improved more than half of the measured care processes, more often when at least five of six implementation strategies were used. In a longer term project, this understanding may have allowed us to adapt the intervention to be effective in more hospitals

Socioeconomic deprivation and mortality after emergency laparotomy: an observational epidemiological study

Background: Socioeconomic circumstances can influence access to healthcare, the standard of care provided, and a variety of outcomes. This study aimed to determine the association between crude and risk-adjusted 30-day mortality and socioeconomic group after emergency laparotomy, measure differences in meeting relevant perioperative standards of care, and investigate whether variation in hospital structure or process could explain any difference in mortality between socioeconomic groups. / Methods: This was an observational study of 58 790 patients, with data prospectively collected for the National Emergency Laparotomy Audit in 178 National Health Service hospitals in England between December 1, 2013 and November 31, 2016, linked with national administrative databases. The socioeconomic group was determined according to the Index of Multiple Deprivation quintile of each patient's usual place of residence. / Results: Overall, the crude 30-day mortality was 10.3%, with differences between the most-deprived (11.2%) and least-deprived (9.8%) quintiles (P<0.001). The more-deprived patients were more likely to have multiple comorbidities, were more acutely unwell at the time of surgery, and required a more-urgent surgery. After risk adjustment, the patients in the most-deprived quintile were at significantly higher risk of death compared with all other quintiles (adjusted odds ratio [95% confidence interval]: Q1 [most deprived]: reference; Q2: 0.83 [0.76–0.92]; Q3: 0.84 [0.76–0.92]; Q4: 0.87 [0.79–0.96]; Q5 [least deprived]: 0.77 [0.70–0.86]). We found no evidence that differences in hospital-level structure or patient-level performance in standards of care explained this association. / Conclusions: More-deprived patients have higher crude and risk-adjusted 30-day mortality after emergency laparotomy, but this is not explained by differences in the standards of care recorded within the National Emergency Laparotomy Audit

Association between surgeon special interest and mortality after emergency laparotomy

© 2019 BJS Society Ltd Published by John Wiley & Sons Ltd Background: Approximately 30 000 emergency laparotomies are performed each year in England and Wales. Patients with pathology of the gastrointestinal tract requiring emergency laparotomy are managed by general surgeons with an elective special interest focused on either the upper or lower gastrointestinal tract. This study investigated the impact of special interest on mortality after emergency laparotomy. Methods: Adult patients having emergency laparotomy with either colorectal or gastroduodenal pathology were identified from the National Emergency Laparotomy Audit database and grouped according to operative procedure. Outcomes included all-cause 30-day mortality, length of hospital stay and return to theatre. Logistic and Poisson regression were used to analyse the association between consultant special interest and the three outcomes. Results: A total of 33 819 patients (28 546 colorectal, 5273 upper gastrointestinal (UGI)) were included. Patients who had colorectal procedures performed by a consultant without a special interest in colorectal surgery had an increased adjusted 30-day mortality risk (odds ratio (OR) 1·23, 95 per cent c.i. 1·13 to 1·33). Return to theatre also increased in this group (OR 1·13, 1·05 to 1·20). UGI procedures performed by non-UGI special interest surgeons carried an increased adjusted risk of 30-day mortality (OR 1·24, 1·02 to 1·53). The risk of return to theatre was not increased (OR 0·89, 0·70 to 1·12). Conclusion: Emergency laparotomy performed by a surgeon whose special interest is not in the area of the pathology carries an increased risk of death at 30 days. This finding potentially has significant implications for emergency service configuration, training and workforce provision, and should stimulate discussion among all stakeholders

Hospital-level evaluation of the effect of a national quality improvement programme: time-series analysis of registry data

Background and objectives: A clinical trial in 93 National Health Service hospitals evaluated a quality improvement programme for emergency abdominal surgery, designed to improve mortality by improving the patient care pathway. Large variation was observed in implementation approaches, and the main trial result showed no mortality reduction. Our objective therefore was to evaluate whether trial participation led to care pathway implementation and to study the relationship between care pathway implementation and use of six recommended implementation strategies. Methods: We performed a hospital-level time-series analysis using data from the Enhanced Peri-Operative Care for High-risk patients trial. Care pathway implementation was defined as achievement of &gt;80% median reliability in 10 measured care processes. Mean monthly process performance was plotted on run charts. Process improvement was defined as an observed run chart signal, using probability-based €shift' and €runs' rules. A new median performance level was calculated after an observed signal. Results: Of 93 participating hospitals, 80 provided sufficient data for analysis, generating 800 process measure charts from 20 305 patient admissions over 27 months. No hospital reliably implemented all 10 processes. Overall, only 279 of the 800 processes were improved (3 (2-5) per hospital) and 14/80 hospitals improved more than six processes. Mortality risk documented (57/80 (71%)), lactate measurement (42/80 (53%)) and cardiac output guided fluid therapy (32/80 (40%)) were most frequently improved. Consultant-led decision making (14/80 (18%)), consultant review before surgery (17/80 (21%)) and time to surgery (14/80 (18%)) were least frequently improved. In hospitals using ≥5 implementation strategies, 9/30 (30%) hospitals improved ≥6 care processes compared with 0/11 hospitals using ≤2 implementation strategies. Conclusion: Only a small number of hospitals improved more than half of the measured care processes, more often when at least five of six implementation strategies were used. In a longer term project, this understanding may have allowed us to adapt the intervention to be effective in more hospitals.</p

Methods of the 7th National Audit Project (NAP7) of the Royal College of Anaesthetists: peri-operative cardiac arrest

Cardiac arrest in the peri-operative period is rare but associated with significant morbidity and mortality. Current reporting systems do not capture many such events, so there is an incomplete understanding of incidence and outcomes. As peri-operative cardiac arrest is rare, many hospitals may only see a small number of cases over long periods, and anaesthetists may not be involved in such cases for years. Therefore, a large-scale prospective cohort is needed to gain a deep understanding of events leading up to cardiac arrest, management of the arrest itself and patient outcomes. Consequently, the Royal College of Anaesthetists chose peri-operative cardiac arrest as the 7th National Audit Project topic. The study was open to all UK hospitals offering anaesthetic services and had a three-part design. First, baseline surveys of all anaesthetic departments and anaesthetists in the UK, examining respondents' prior peri-operative cardiac arrest experience, resuscitation training and local departmental preparedness. Second, an activity survey to record anonymised details of all anaesthetic activity in each site over 4 days, enabling national estimates of annual anaesthetic activity, complexity and complication rates. Third, a case registry of all instances of peri-operative cardiac arrest in the UK, reported confidentially and anonymously, over 1 year starting 16 June 2021, followed by expert review using a structured process to minimise bias. The definition of peri-operative cardiac arrest was the delivery of five or more chest compressions and/or defibrillation in a patient having a procedure under the care of an anaesthetist. The peri-operative period began with the World Health Organization 'sign-in' checklist or first hands-on contact with the patient and ended either 24 h after the patient handover (e.g. to the recovery room or intensive care unit) or at discharge if this occured earlier than 24 h. These components described the epidemiology of peri-operative cardiac arrest in the UK and provide a basis for developing guidelines and interventional studies

Specialist Peri-Operative Allergy Clinic Services in the UK 2016: Results from the Royal College of Anaesthetists Sixth National Audit Project (NAP6)

BACKGROUND: Guidelines for investigation of perioperative drug allergy exist, but the quality of services is unknown. Specialist perioperative anaphylaxis services were surveyed through the Royal College of Anaesthetists 6(th) National Audit Project. OBJECTIVES: We compare self-declared UK practice in specialist perioperative allergy services with national recommendations. METHODS: A SurveyMonkey(™) questionnaire was distributed to providers of allergy services in the UK. Responses were assessed for adherence to the best practice recommendations of the British Society for Allergy and Clinical Immunology, the Association of Anaesthetists of Great Britain and Ireland and the National Institute for Health and Care Excellence (NICE) Guidance on Drug Allergy - CG183. RESULTS: Over 1200 patients were evaluated in 44 centres annually. Variation in workload, waiting times, access, staffing and diagnostic approach was noted. Paediatric centres had the longest routine waiting times (most wait >13 weeks) in contrast to adult centres (most wait <12 weeks). Service leads are allergists/immunologists (91%) or anaesthetists (7%). Potentially important differences were seen in: testing repertoire [10/44 (23%) lacked BSACI compliant NMBA panels and 17/44 (39%) lacked a NAP6-defined extended panel; many failed to screen all cases for chlorhexidine 19/44 (43%) or latex 21/44 (48%)], staffing [only 26/44 (59%) had specialist nurses and 18/44 (41%) an anaesthetist], and provision of information [18/44 (41%) gave immediate information in clinic, and 5/44 (11%) on support groups]. Most centres were able to provide diagnostic challenges to antibiotics [40/44 (91%]) and local anaesthetics [41/44 (93%)]. CONCLUSIONS AND CLINICAL RELEVANCE: Diagnostic testing is not harmonised, with marked variability in the NMBA panels used to identify safe alternatives. Chlorhexidine and latex are not part of routine testing in many centres. Poor access to services and patient information provision require attention. Harmonisation of diagnostic approach is desirable, particularly with regard to a minimum NMBA panel for identification of safe alternatives. This article is protected by copyright. All rights reserved

Predicting severe pain after major surgery: a secondary analysis of the Peri-operative Quality Improvement Programme (PQIP) dataset

Acute postoperative pain is common, distressing and associated with increased morbidity. Targeted interventions can prevent its development. We aimed to develop and internally validate a predictive tool to pre-emptively identify patients at risk of severe pain following major surgery. We analysed data from the UK Peri-operative Quality Improvement Programme to develop and validate a logistic regression model to predict severe pain on the first postoperative day using pre-operative variables. Secondary analyses included the use of peri-operative variables. Data from 17,079 patients undergoing major surgery were included. Severe pain was reported by 3140 (18.4%) patients; this was more prevalent in females, patients with cancer or insulin-dependent diabetes, current smokers and in those taking baseline opioids. Our final model included 25 pre-operative predictors with an optimism-corrected c-statistic of 0.66 and good calibration (mean absolute error 0.005, p = 0.35). Decision-curve analysis suggested an optimal cut-off value of 20–30% predicted risk to identify high-risk individuals. Potentially modifiable risk factors included smoking status and patient-reported measures of psychological well-being. Non-modifiable factors included demographic and surgical factors. Discrimination was improved by the addition of intra-operative variables (likelihood ratio χ2 496.5, p < 0.001) but not by the addition of baseline opioid data. On internal validation, our pre-operative prediction model was well calibrated but discrimination was moderate. Performance was improved with the inclusion of peri-operative covariates suggesting pre-operative variables alone are not sufficient to adequately predict postoperative pain

Design, Construction and Installation of the ATLAS Hadronic Barrel Scintillator-Tile Calorimeter

The scintillator tile hadronic calorimeter is a sampling calorimeter using steel as the absorber structure and scintillator as the active medium. The scintillator is located in "pockets" in the steel structure and the wavelength-shifting fibers are contained in channels running radially within the absorber to photomultiplier tubes which are located in the outer support girders of the calorimeter structure. In addition, to its role as a detector for high energy particles, the tile calorimeter provides the direct support of the liquid argon electromagnetic calorimeter in the barrel region, and the liquid argon electromagnetic and hadronic calorimeters in the endcap region. Through these, it indirectly supports the inner tracking system and beam pipe. The steel absorber, and in particular the support girders, provide the flux return for the solenoidal field from the central solenoid. Finally, the end surfaces of the barrel calorimeter are used to mount services, power supplies and readout crates for the inner tracking systems and the liquid argon barrel electromagnetic calorimeter