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11.
Ultrasound scanning of bladder volume is used for prevention of postoperative urinary retention (POUR). Accurate assessment of bladder volume is needed to allow clinical decision-making regarding the need for postoperative catheterization. Two commonly used ultrasound devices, the BladderScan® BVI 9400 and the newly released Prime® (Verathon Medical®, Bothell, WA, USA), with or without the ‘pre-scan’ option, have not been validated in clinical practice. The aim of this study was to assess the performance of these devices in daily clinical practice. Between June and September 2016 a prospective observational study was conducted in 318 surgical patients (18 years or older) who needed a urinary catheter perioperatively for clinical reasons. For acceptable performance, we required that the volume as estimated by the BladderScan® differs by no more than 5% from the actual urine volume after catheterization. The Schuirmann’s two one-sided test was performed to assess equivalence between the BladderScan® estimate and catheterization. The BVI 9400® overestimated the actual bladder volume by +?17.5% (95% CI +?8.8 to +?26.3%). The Prime® without pre-scan underestimated by ? 4.1% (95% CI ? 8.8 to +?0.5%) and the Prime® with pre-scan underestimated by ? 6.3% (95% CI ? 11.6 to ? 1.1%). This study shows that while both ultrasound devices were able to approximate current bladder volume, both BVI 9400® and Prime®—with and without pre-scan—were not able to measure the actual bladder volume within our predefined limit of ±?5%. Using the pre-scan feature of the Prime® did not further improve accuracy.  相似文献   
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Peer support is increasingly provided as a component of mental health care, where people in recovery from mental health problems use their lived experiences to provide support to those experiencing similar difficulties. In the present study, we explored the evolution of peer support workers’ (PSW) occupational identities. A qualitative study was undertaken alongside a pilot randomized, controlled trial of peer support for service users discharged from a mental hospital in London, UK. Two focus groups were conducted with eight PSW. Semistructured interviews were conducted with 13 service users receiving peer support and on two occasions with a peer support coordinator. The data were analysed using theoretical thematic analysis, focussing on occupational identity formation. We discuss how the occupational identity of PSW evolved through the interplay between their lived experience, their training, and their engagement in the practice environment in such a way as to construct a liminal identity, with positive and negative outcomes. While the difficulties associated with the liminality of PSW could be eased through the formalization and professionalization of the PSW role, there are concerns that this could lead to an undermining of the value of PSW in providing a service by peers for peers that is separate from formal mental health care and relationships. Skilled support is essential in helping PSW negotiate the potential stressors and difficulties of a liminal PSW identity.  相似文献   
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The discourse of leaderism in health care has been a subject of much academic and practical debate. Recently, distributed leadership (DL) has been adopted as a key strand of policy in the UK National Health Service (NHS). However, there is some confusion over the meaning of DL and uncertainty over its application to clinical and non‐clinical staff. This article examines the potential for DL in the NHS by drawing on qualitative data from three co‐located health‐care organisations that embraced DL as part of their organisational strategy. Recent theorising positions DL as a hybrid model combining focused and dispersed leadership; however, our data raise important challenges for policymakers and senior managers who are implementing such a leadership policy. We show that there are three distinct forms of disconnect and that these pose a significant problem for DL. However, we argue that instead of these disconnects posing a significant problem for the discourse of leaderism, they enable a fantasy of leadership that draws on and supports the discourse.  相似文献   
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OBJECTIVES: The purpose of this study was to evaluate the hypothesis that presumed reversion of electrical remodeling after cardioversion of atrial fibrillation (AF) restores the efficacy of flecainide. BACKGROUND: Flecainide loses its efficacy to cardiovert when AF has been present for more than 24 hours. Most probably, the loss is caused by atrial electrical remodeling. Studies suggest electrical remodeling is completely reversible within 4 days after restoration of sinus rhythm (SR). METHODS: One hundred eighty-one patients with persistent AF (median duration 3 months) were included in this prospective study. After failure of pharmacologic cardioversion by flecainide 2 mg/kg IV (maximum 150 mg in 10 minutes) and subsequent successful electrical cardioversion, we performed intense transtelephonic rhythm monitoring three times daily for 1 month. In case of AF recurrence, a second cardioversion by flecainide was attempted as soon as possible. RESULTS: AF recurred in 123 patients (68%). Successful cardioversion by flecainide occurred only when SR had been maintained for more than 4 days (7/51 patients [14%]). Failure to cardiovert was associated with a prolonged duration of the recurrent AF episode and concurrent digoxin use. Multivariate logistic regression confirmed that successful cardioversion was determined by digoxin use (odds ratio [OR] 0.093, P = .047) and by the interaction between the duration of SR and the (inverse) duration of recurrent AF (OR 6.499, P < .001). When flecainide was administered within 10 hours after AF onset and the duration of SR was greater than 4 days, the success rate was 58%. CONCLUSIONS: Flecainide recovers its antiarrhythmic action after cardioversion of AF. However, successful pharmacologic cardioversion occurs only after SR has lasted at least 4 days and is expected only for recurrences having duration of a few hours. Immediate pharmacologic cardioversion of AF recurrence may be a worthwhile strategy for management of persistent AF.  相似文献   
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Abstract – Aims: This study sought to establish the prevalence of traumatic dental injuries in the primary dentition of Irish children and to investigate the relationship between dental trauma and non‐nutritive sucking habits. Materials and methods: Following ethical approval, a variety of schools and crèches in an urban setting were identified and parents of over 1000 children were contacted. Consent was obtained, and parental questionnaires were completed prior to a clinical examination of the children by one operator in a non‐dental setting. Signs of previous dental trauma were noted, and overbite and overjet were measured. Results: Eight hundred and thirty‐nine children were examined. The prevalence of dental trauma was 25.6%, with boys more frequently affected. The most commonly observed dental injury was fracture of enamel (39.4%), followed by crown discolouration (20.2%). Only 38.8% of the children with a reported history of trauma sought dental care. Non‐nutritive sucking habits were reported in 63.5% of the sample, and these habits, if prolonged, were significantly associated with anterior open bites and increased overjet (P < 0.001). Using regression analysis, it was established that the risk of dental injury is 2.99 times greater if the child has an overjet >6 mm and 2.02 times greater if the child has an anterior open bite. Conclusions: Non‐nutritive sucking habits are associated with the establishment of anterior open bite and increased overjet in the primary dentition. These malocclusions are, in turn, significantly associated with an increased prevalence of dental trauma in the primary dentition.  相似文献   
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No previous research in squash has considered the time between shots or the proximity of the ball to a wall, which are two important variables that influence shot outcomes. The aim of this paper was to analyse shot types to determine the extent to which they are played in different court areas and a more detailed analysis to determine whether the time available had an influence on the shot selected. Ten elite matches, contested by fifteen of the world’s top right handed squash players (age 27 ± 3.2, height 1.81 ± 0.06 m, weight 76.3 ± 3.7 kg), at the men’s World Team Championships were processed using the SAGIT/Squash tracking system with shot information manually added to the system. Results suggested that shot responses were dependent upon court location and the time between shots. When these factors were considered repeatable performance existed to the extent that one of two shots was typically played when there was limited time to play the shot (< 1.20s). For example, it was clear that when players did not have a lot of time to hit the ball (low time i.e. < 1.06s, and mid time i.e. 1.06 - 1.20s) in the front left corner close to the side wall, the crosscourt lob was used frequently (44.30% and 36.31% respectively) whereas when there was more time this shot was seldom used (13.64%). Consequently variant and invariant behaviour were shown to exist in elite squash although for the first time it was suggested that the availability of time to play a shot contributed to which of these behaviours was evident. This analysis could be extended by adopting a case study approach to see how individual differences in strategy and tactics affect shot selections.

Key points

  • Previous research has suggested that a playing strategy, elements decided in advance of the match, may be evident for elite players by examining court location and preceding shot type, however these parameters alone are unlikely to be sufficient predictors.
  • At present there is no known analysis in squash, or indeed in any of the racket sports, that has quantified the time available to respond to different shot types. An understanding of the time interval between shots and the movement characteristics of the player responding to different shots according to the court positions might facilitate a better understanding of the dynamics that determine shot selection.
  • Some elements of a general playing strategy were evident e.g. predominately hitting to the back left of the court, but tactical differences in shot selection were also evident on the basis of court location and time available to play a shot.
Key words: Strategy, tactics, SAGIT, invariant behaviour.  相似文献   
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