2,166 research outputs found
Estudo numérico do comportamento de ancoragens de pré-esforço por aderência
Com a procura crescente na área da reabilitação de edifícios surge a necessidade de desenvolver métodos e técnicas de reforço que permitam soluções integradas nas construções existentes, conferindo desempenho e segurança. Neste contexto pretende-se desenvolver um estudo sobre a utilização de um sistema de pré-esforço por pós-tensão com ancoragens por aderência. Uma das técnicas associadas a este sistema de pré-esforço tem vindo a ser desenvolvida na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, à qual se pretende dar continuidade.
Este trabalho tem como objetivo principal analisar o desenvolvimento de tensões no betão, mediante a utilização de ancoragens de pré-esforço por aderência. Este estudo é conseguido através de análises numéricas elaboradas no software, ATENA 3D (Advanced Tool for Engineering Nonlinear Analysis Three-Dimensional), que considera o comportamento não linear dos materiais.
Foram considerados 3 modelos diferentes com recurso a uma lei de aderência uniforme elaborada a partir dos resultados da campanha experimental, tendo sido calibrados de forma a obter um afastamento inferior a 10 % entre resultados experimentais e numéricos. Na parametrização foram consideradas as especificações de cada modelo, analisando a variação do comprimento aderente num cordão sem introdução de força de pré-esforço, a variação do comprimento aderente para uma força de pré-esforço constante e a variação da força de pré-esforço para um comprimento aderente constante.
Do estudo desenvolvido foi possível verificar que o comprimento aderente é responsável pelo aumento da força última e que a introdução de uma força de pré-esforço permite uma melhor distribuição das tensões no betão
Factors associated to vascular pedicle width in ARDS
Introduction: In previous studies, vascular pedicle width (VPW) was the best radiographic sign of intravascular volume status in critically ill patients and may enhance implementation and acceptance of the conservative fluid strategy into routine clinical practice. Objective: Our aim was to find the relationship among VPW and parameters of mechanical ventilation (MV) and baseline data. The hypothesis was that pressures, tidal volume and baseline data, as age, could be related to VPW in acute respiratory distress syndrome (ARDS). Methodology: It was a retrospective cohort study enrolled in the Open Lung Approach trial performed in moderate-severe acute respiratory distress syndrome recruited in São Paulo, Brazil. VPW was measured by two investigators in chestradiographs taken at diagnosis and after 24 hours of mechanical ventilation adjustments. The relationship between VPW, age, predicted body weight (PBW), positive end-expiratory pressure (PEEP), plateau pressure and tidal volume adjusted by PBW were evaluated. Results: 26 patients were included in analysis, with a total of 52 chest radiography analyzed. There was a significant change in VPW between diagnosis and after 24hours from MV adjustments (r = 0.64, p < 0.01). Age was related to VPW before and after adjustments in MV (r= 0.57, p < 0.01). No correlation was found between MV parameters (PEEP, plateau pressure and tidal volume) with VPW. Conclusions: There was no correlation among pressures and tidal volume applied during MV and PDW, reinforcing thismethod as an easy, wide available and noninvasive way to estimate intravascular volume status in ARDS patients. Age was related to VPW, suggesting that the measure of VPW could be improved after correction based in this parameter
Brazilian guidelines for the treatment of outpatients with suspected or confirmed COVID-19 : a joint guideline of the Brazilian Association of Emergency Medicine (ABRAMEDE), Brazilian Medical Association (AMB), Brazilian Society of Angiology and Vascular Surgery (SBACV), Brazilian Society of Geriatrics and Gerontology (SBGG), Brazilian Society of Infectious Diseases (SBI), Brazilian Society of Family and Community Medicine (SBFMC), and Brazilian Thoracic Society (SBPT)
Background: Several therapies have been used or proposed for the treatment of COVID-19, although their effectiveness and safety have not been properly evaluated. The purpose of this document is to provide recommendations to support decisions about the drug treatment of outpatients with COVID-19 in Brazil. Methods: A panel consisting of experts from different clinical fields, representatives of the Brazilian Ministry of Health, and methodologists (37 members in total) was responsible for preparing these guidelines. A rapid guideline development method was used, based on the adoption and/or adaptation of recommendations from existing international guidelines combined with additional structured searches for primary studies and new recommendations whenever necessary (GRADE-ADOLOPMENT). The rating of quality of evidence and the drafting of recommendations followed the GRADE method. Results: Ten technologies were evaluated, and 10 recommendations were prepared. Recommendations were made against the use of anticoagulants, azithromycin, budesonide, colchicine, corticosteroids, hydroxychloroquine/chloroquine alone or combined with azithromycin, ivermectin, nitazoxanide, and convalescent plasma. It was not possible to make a recommendation regarding the use of monoclonal antibodies in outpatients, as their benefit is uncertain and their cost is high, with limitations of availability and implementation. Conclusion: To date, few therapies have demonstrated effectiveness in the treatment of outpatients with COVID-19. Recommendations are restricted to what should not be used, in order to provide the best treatment according to the principles of evidence-based medicine and to promote resource savings by aboiding ineffective treatments
Shortening ventilatory support with a protocol based on daily extubation screening and noninvasive ventilation in selected patients
BACKGROUND: Prolonged invasive mechanical ventilation and reintubation are associated with adverse outcomes and increased mortality. Daily screening to identify patients able to breathe without support is recommended to reduce the length of mechanical ventilation. Noninvasive positive-pressure ventilation has been proposed as a technique to shorten the time that patients remain on invasive ventilation. METHODS: We conducted a before-and-after study to evaluate the efficacy of an intervention that combined daily screening with the use of noninvasive ventilation immediately after extubation in selected patients. The population consisted of patients who had been intubated for at least 2 days. RESULTS: The baseline characteristics were similar between the groups. The intervention group had a lower length of invasive ventilation (6 [4;9] vs. 7 [4;11.5] days, p = 0.04) and total (invasive plus noninvasive) ventilator support (7 [4;11] vs. 9 [6;8], p = 0.01). Similar reintubation rates within 72 hours were observed for both groups. In addition, a lower ICU mortality was found in the intervention group (10.8% vs. 24.3%, p = 0.03), with a higher cumulative survival probability at 60 days (p = 0.05). Multivariate analysis showed that the intervention was an independent factor associated with survival (RR: 2.77; CI 1.14-6.65; p = 0.03), whereas the opposite was found for reintubation at 72 hours (RR: 0.27; CI 0.11-0.65; p = 0.01). CONCLUSION: The intervention reduced the length of invasive ventilation and total ventilatory support without increasing the risk of reintubation and was identified as an independent factor associated with survival
Prevalência de infecção em unidades de terapia intensiva de um hospital escola terciário
OBJECTIVE: To determine the prevalence rates of infections among intensive care unit patients, the predominant infecting organisms, and their resistance patterns. To identify the related factors for intensive care unit-acquired infection and mortality rates. DESIGN: A 1-day point-prevalence study. SETTING:A total of 19 intensive care units at the Hospital das Clínicas - University of São Paulo, School of Medicine (HC-FMUSP), a teaching and tertiary hospital, were eligible to participate in the study. PATIENTS: All patients over 16 years old occupying an intensive care unit bed over a 24-hour period. The 19 intensive care unit s provided 126 patient case reports. MAIN OUTCOME MEASURES: Rates of infection, antimicrobial use, microbiological isolates resistance patterns, potential related factors for intensive care unit-acquired infection, and death rates. RESULTS: A total of 126 patients were studied. Eighty-seven patients (69%) received antimicrobials on the day of study, 72 (57%) for treatment, and 15 (12%) for prophylaxis. Community-acquired infection occurred in 15 patients (20.8%), non- intensive care unit nosocomial infection in 24 (33.3%), and intensive care unit-acquired infection in 22 patients (30.6%). Eleven patients (15.3%) had no defined type. The most frequently reported infections were respiratory (58.5%). The most frequently isolated bacteria were Enterobacteriaceae (33.8%), Pseudomonas aeruginosa (26.4%), and Staphylococcus aureus (16.9%; [100% resistant to methicillin]). Multivariate regression analysis revealed 3 risk factors for intensive care unit-acquired infection: age >; 60 years (p = 0.007), use of a nasogastric tube (p = 0.017), and postoperative status (p = 0.017). At the end of 4 weeks, overall mortality was 28.8%. Patients with infection had a mortality rate of 34.7%. There was no difference between mortality rates for infected and noninfected patients (p=0.088). CONCLUSION: The rate of nosocomial infection is high in intensive care unit patients, especially for respiratory infections. The predominant bacteria were Enterobacteriaceae, Pseudomonas aeruginosa, and Staphylococcus aureus (resistant organisms). Factors such as nasogastric intubation, postoperative status, and age ³60 years were significantly associated with infection. This study documents the clinical impression that prevalence rates of intensive care unit-acquired infections are high and suggests that preventive measures are important for reducing the occurrence of infection in critically ill patients.OBJETIVO: Determinar a prevalência de infecções em pacientes de Terapia Intensiva, os agentes infecciosos mais comuns e seus padrões de resistência. Identificar os fatores relacionados a infecção adquirida na Unidade de Terapia Intensiva e as taxas de mortalidade. DESENHO: Estudo de prevalência de um dia. LOCAL:Um total de 19 Unidades de Terapia Intensiva do Hospital das Clínicas da FMUSP (HC-FMUSP) participaram do estudo. PACIENTES: Todos os pacientes com idade superior a 16 anos internados em leitos de terapia intensiva por mais de 24 horas foram incluídos. As 19 Unidades de Terapia Intensiva forneceram 126 casos. VARIÁVEIS:Taxas de infecção, uso de antibióticos, padrões de resistência microbiológica, fatores relacionados à infecção adquirida na Unidade de Terapia Intensiva, taxas de mortalidade. RESULTADOS: Um total de 126 pacientes foi estudado. Oitenta e sete (69%) receberam antibióticos no dia do estudo, sendo 72 (57%) para tratamento e 15 (12%) para profilaxia. Baseado no tipo, observou-se que a infecção adquirida na comunidade ocorreu em 15 pacientes (20,8%), infecção hospitalar fora da Unidade de Terapia Intensiva em 24 (33,3%), e infecção adquirida na Unidade de Terapia Intensiva em 22 pacientes (30,6%). Para 11 pacientes (15,3%) não se definiu o tipo de infecção. Quanto ao sítio de infecção, as respiratórias foram as infecções mais comuns (58,5%). Os agentes mais freqüentemente isolados foram: Enterobacteriaceae (33,8%), Pseudomonas aeruginosa (26,4%) e Staphylococcus aureus (16,9%; 100% meticilina-resistentes). Análise multivariada identificou 3 fatores associados à infecção adquirida na Unidade de Terapia Intensiva: idade maior ou igual a 60 anos (p=0,007), uso de sonda nasogástrica (p=0,017) e pós-operatório (p=0,017). Ao final de quatro semanas, a taxa de mortalidade foi de 28,8%. Entre os infectados, a mortalidade foi de 34,7%. Não houve diferença entre as taxas de mortalidade para pacientes infectados e não-infectados (p=0,088). CONCLUSÃO: A taxa de infecção é alta entre os pacientes de terapia intensiva, especialmente as infecções respiratórias. As bactérias predominantes foram: Enterobacteriaceae. Pseudomonas aeruginosa e Staphylococcus aureus (agentes resistentes). Fatores como uso de sonda nasogástrica, pós-operatório e idade maior ou igual a 60 anos mostraram associação com infecção. Este estudo documenta a impressão clínica de que a prevalência de infecção adquirida na Unidade de Terapia Intensiva é alta e sugere que medidas preventivas são importantes para reduzir a ocorrência de infecção em pacientes críticos
Infection as an independent risk factor for mortality in the surgical intensive care unit
OBJECTIVES: Medical and surgical intensive care unit patients represent two different populations and require different treatment approaches. The aim of this study was to investigate the parameters associated with mortality in medical and surgical intensive care units. METHODS: This was a prospective cohort study of adult patients admitted to a medical and surgical intensive care unit teaching hospital over an 11-month period. Factors associated with mortality were explored using logistic regression analysis. RESULTS: In total, 827 admissions were observed, and 525 patients >;18 years old and with a length of stay >;24 h were analyzed. Of these patients, 227 were in the medical and 298 were in the surgical intensive care unit. The surgical patients were older (
Immunoglobulin G4-related systemic sclerosing disease in a patient with sclerosing cholangitis, inflammatory pseudotumors of the lung and multiple radiological patterns: a case report
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