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Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement—atrial functional TR (AF‐TR)—remains largely underappreciated. AF‐TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF‐TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF‐TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR.  相似文献   
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Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.

Methods

Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.

Results

A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.

Conclusions

Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.  相似文献   
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A comparative study involving bimetallic nickel catalysts designed from disubstituted N,N,N′,N′‐tetra(diphenylphosphanylmethyl)benzene diamine bridging ligands is reported. Catalyst behavior is explored in the Kumada catalyst‐transfer polymerization (KCTP) using poly(3‐hexylthiophene) (P3HT) as the model system. The success of a controlled polymerization is monitored by analyzing monomer conversion, degree of polymerization, end‐group identity, and molecular weight distribution. The characterization of P3HT obtained from KCTP initiated with the bimetallic catalysts shows chain‐growth behavior; however, the presence of Br/Br end‐groups and broader molecular weight distribution reveals a reduced controlled polymerization compared to the commonly employed Ni(dppp)Cl2. The observed increase in intermolecular chain transfer and termination processes in KCTP initiation with the bimetallic catalysts can be attributed to a weaker Ni(0)‐π‐aryl complex interaction, which is caused by increased steric crowding of the coordination sphere.  相似文献   
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Echoes     
Hazel Edwards 《Ultrasound》2015,23(2):131-132
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The profile and reach of physiotherapy has expanded in areas of extended scope of practice, and broader engagement with population needs beyond the individual treatment encounter. These changes raise increasingly complex ethical challenges evidenced by growth in physiotherapy-based ethics studies and discussions. This paper examines how a broad cross section of Australian physiotherapists perceive, interpret, and respond to ethical challenges in their work contexts and how professional codes of conduct are used in their practice. Using an interpretive qualitative methodology, purposive sampling of 88 members of national clinical special interest groups were recruited for focus group discussions. Narrative-based and thematic data analysis identified ethical challenges as emerging from specific clinical contexts, and influenced by health organizations, funding policies, workplace relationships, and individually held perspectives. Five themes were developed to represent these findings: (1) the working environment, (2) balancing diverse needs and expectation, (3) defining ethics, (4) striving to act ethically, and (5) talking about ethics. The results portray a diverse and complex ethical landscape where therapists encounter and grapple with ethical questions emerging from the impact of funding models and policies affecting clinical work, expanding boundaries and scope of practice and changing professional roles and relationships. Codes of conduct were described as foundational ethical knowledge but not always helpful for “in the moment” ethical decision-making. Based on this research, we suggest how codes of conduct, educators, and professional associations could cultivate and nurture ethics capability in physiotherapy practitioners for these contemporary challenges.  相似文献   
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