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1.
Ann Thorac Surg ; 113(1): 13-24, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34536378

RESUMO

The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (ACSD) is the world's premier clinical outcomes registry for adult cardiac surgery and a driving force for quality improvement in cardiac surgery. Echocardiographic data provide a wealth of hemodynamic, structural, and functional data and have been part of STS ACSD data collection since its inception. An increasing body of evidence suggests that the use of echocardiography in patients undergoing cardiac surgery has a positive impact on postoperative outcomes. In this report, we describe and summarize the type and rate of reporting of echocardiography-related variables in the STS ACSD, including the Adult Cardiac Anesthesiology Module, from July 2017 to December 2019 for the most frequently performed cardiac surgical procedures. With this review, we aim to increase awareness of the importance of collecting accurate and consistent echocardiography data in the STS ACSD and to highlight opportunities for growth and improvement.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ecocardiografia , Adulto , Valva Aórtica/cirurgia , Ponte de Artéria Coronária , Bases de Dados Factuais , Coração Auxiliar , Humanos , Valva Mitral/cirurgia , Placa Aterosclerótica/cirurgia , Sociedades Médicas , Cirurgiões , Cirurgia Torácica , Função Ventricular Direita
2.
Trauma Case Rep ; 31: 100380, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33385056

RESUMO

Percutaneous iliosacral screw placement has become the technique of choice for treating injuries to the posterior pelvis. However, the technique requires an understanding of the anatomy surrounding the bone corridors to avoid complications and detect them early if they occur. We present the clinical case of a patient with a U-shaped fracture of the sacrum that evolves with gluteal pain and left foot equine paresis after percutaneous fixation with iliosacral screws. Angio-CT of the pelvis shows active arterial bleeding from the superior gluteal artery associated to extensive hematoma in the thickness of the gluteus medius muscle. Emergency embolization is performed by installing coil and gelatin. Successful control of bleeding is achieved. To avoid this complication, a complete imaging study is recommended in planning the surgery and to avoid multiple repositioning of the guide or screw. Arterial injury should be suspected in case of increasing pain despite analgesia, functional impairment or neurological deficit and the angiographic study and resolution by selective embolization of the bleeding vessels must be performed.

3.
J Cardiothorac Vasc Anesth ; 35(1): 22-34, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33008722

RESUMO

The Society of Cardiovascular Anesthesiologists, in partnership with The Society of Thoracic Surgeons, has developed the Adult Cardiac Anesthesiology Section of the Adult Cardiac Surgery Database. The goal of this landmark collaboration is to advance clinical care, quality, and knowledge, and to demonstrate the value of cardiac anesthesiology in the perioperative care of cardiac surgical patients. Participation in the Adult Cardiac Anesthesiology Section has been optional since its inception in 2014 but has progressively increased. Opportunities for further growth and improvement remain. In this first update report on quality and outcomes of the Adult Cardiac Anesthesiology Section, we present an overview of the clinically significant anesthesia and surgical variables submitted between 2015 and 2018. Our review provides a summary of quality measures and outcomes related to the current practice of cardiothoracic anesthesiology. We also emphasize the potential for addressing high-impact research questions as data accumulate, with the overall goal of elucidating the influence of cardiac anesthesiology contributions to patient outcomes within the framework of the cardiac surgical team.


Assuntos
Anestesia , Anestesiologia , Procedimentos Cirúrgicos Cardíacos , Cirurgia Torácica , Adulto , Humanos , Sociedades Médicas
5.
Ann Thorac Surg ; 110(5): 1447-1460, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33008569

RESUMO

The Society of Cardiovascular Anesthesiologists, in partnership with The Society of Thoracic Surgeons, has developed the Adult Cardiac Anesthesiology Section of the Adult Cardiac Surgery Database. The goal of this landmark collaboration is to advance clinical care, quality, and knowledge, and to demonstrate the value of cardiac anesthesiology in the perioperative care of cardiac surgical patients. Participation in the Adult Cardiac Anesthesiology Section has been optional since its inception in 2014 but has progressively increased. Opportunities for further growth and improvement remain. In this first update report on quality and outcomes of the Adult Cardiac Anesthesiology Section, we present an overview of the clinically significant anesthesia and surgical variables submitted between 2015 and 2018. Our review provides a summary of quality measures and outcomes related to the current practice of cardiothoracic anesthesiology. We also emphasize the potential for addressing high-impact research questions as data accumulate, with the overall goal of elucidating the influence of cardiac anesthesiology contributions to patient outcomes within the framework of the cardiac surgical team.


Assuntos
Anestesia/normas , Anestesiologia , Procedimentos Cirúrgicos Cardíacos/normas , Gerenciamento de Dados , Bases de Dados Factuais , Sociedades Médicas , Cirurgia Torácica , Adulto , Humanos , Complicações Pós-Operatórias/etiologia , Indicadores de Qualidade em Assistência à Saúde , Qualidade da Assistência à Saúde , Resultado do Tratamento , Estados Unidos
6.
Rev Epidemiol Sante Publique ; 68(5): 282-287, 2020 Sep.
Artigo em Francês | MEDLINE | ID: mdl-32855006

RESUMO

INTRODUCTION: Frailty is a transient and reversible condition that can lead to significant morbidity and mortality and to the loss of autonomy. It is one of the key issues in public health and the prevention of addiction. Physical activity is often described as a protective factor against addiction and as a factor in limiting frailty. Our goal is to analyze the relationship between physical activity and frailty among the elderly METHODS: A cross-sectional observational study was carried out in three general practice clinics located in the French department of Eure. Patients aged 65 and over were included during a consultation with their GP. Dependent patients under the ADL scale were excluded. Level of physical activity was assessed by the Ricci and Gagnon questionnaire, which defines an active profile as a score≥18 points. Frailty was sought out by the Fried scale and the SEGA A grid. Multivariate analysis was performed to adjust frailty scores to age, gender, and level of physical activity. RESULTS: Out of the 70 patients included, 36 were active (51%) and 34 inactive (49%). They were predominantly female with 47 women (67%). Average age was 75.3years. Twelve patients were diagnosed as frail (17%) with the Fried scale and 24 (34%) with the SEGA A grid. Bivariate analysis revealed a greater frailty according to the Fried criteria in the inactive than in the active patients (mean for active patients 0.56 IC95 [0.31; 0.80], compared to 1.76 [1.21; 2.32] in the inactive patients, p<0.0001). The difference in mean was likewise significant regarding the SEGA A score (6.42 IC95 [5.34, 7.49] in the active population, as opposed to 8.65 IC95 [7.15, 10.15] among the inactive, p=0.017). In multivariate analysis, the Fried scale was primarily influenced by age and ADL, while the SEGA score was impacted by female gender and level of physical activity. CONCLUSION: Physical activity seems to have a positive effect on frailty. It would be interesting to propose systematic screening for frailty in general medicine and to institute preventive measures, including physical activity. Initiatives encouraging and promoting seniors' physical activity should be strengthened.


Assuntos
Exercício Físico/fisiologia , Fragilidade/terapia , Medicina Geral/métodos , Padrões de Prática Médica/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Medicina Geral/estatística & dados numéricos , Avaliação Geriátrica/estatística & dados numéricos , Humanos , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Estudos Prospectivos , Encaminhamento e Consulta/estatística & dados numéricos
7.
Rev Neurol ; 70(11): 417-429, 2020 Jun 01.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-32436209

RESUMO

INTRODUCTION: Like every year, after the ECTRIMS Congress, renowned Spanish neurologists who are experts in multiple sclerosis presented the main novelties in research in this field at the Post-ECTRIMS Meeting. AIM: To summarise the content presented at the 12th edition of the Post-ECTRIMS Meeting, which took place in September 2019 in Sevilla and is presented in two parts. DEVELOPMENT: In this second part, the most recent evidence on the use of disease-modifying treatments during pregnancy is presented. Details are provided concerning the results of phase 3 clinical trials conducted to evaluate the efficacy and safety of two potential disease-modifying treatments for relapsing-remitting multiple sclerosis: ponesimod and ofatumumab. For the progressive forms, both available disease modifying treatments and others still in the research phase are reviewed. In the field of stem cell therapies, the article includes the results of the only clinical trial carried out to date comparing patients with relapsing-remitting multiple sclerosis treated with autologous haematopoietic stem cell transplantation and those treated with disease-modifying therapies. There are no important developments as regards symptomatic treatments, although the European Academy of Neurology has published a guide on palliative care. The various sources of information that collect pharmacovigilance data in the post-marketing setting are reviewed. CONCLUSIONS: Patients diagnosed in recent years tend to have less severe multiple sclerosis, probably due to the fact that it is diagnosed in its milder stages together with the steady increase in the number of treatments available.


TITLE: XII Reunión Post-ECTRIMS: revisión de las novedades presentadas en el Congreso ECTRIMS 2019 (II).Introducción. Como cada año, tras la celebración del Congreso del ECTRIMS, reconocidos neurólogos españoles expertos en esclerosis múltiple expusieron en la Reunión Post-ECTRIMS las principales novedades en investigación en este ámbito. Objetivo. Sintetizar el contenido presentado en la XII edición de la Reunión Post-ECTRIMS, que tuvo lugar en septiembre de 2019 en Sevilla y que se presenta en dos partes. Desarrollo. En esta segunda parte, se exponen las evidencias más recientes sobre el uso de tratamientos modificadores de la enfermedad durante el embarazo. Se detallan los resultados de ensayos clínicos en fase 3 en los que se ha evaluado la eficacia y la seguridad de dos potenciales tratamientos modificadores de la enfermedad para la esclerosis múltiple remitente recurrente: ponesimod y ofatumumab. Para las formas progresivas, se revisan los tratamientos modificadores de la enfermedad disponibles y en investigación. En el ámbito de las terapias con células madre, se incluyen los resultados del único ensayo clínico hasta la fecha que compara a pacientes con esclerosis múltiple remitente recurrente tratados con trasplante autólogo de células madre hematopoyéticas y a los tratados con tratamientos modificadores de la enfermedad. No hay grandes novedades sobre tratamientos sintomáticos, aunque la Academia Europea de Neurología ha publicado una guía sobre cuidados paliativos. Se revisan las distintas fuentes de información que recogen datos de farmacovigilancia en el entorno poscomercialización. Conclusiones. Los pacientes diagnosticados en los últimos años tienden a tener una menor gravedad de la esclerosis múltiple, probablemente debido al diagnóstico desde sus estadios más leves y al continuo aumento de tratamientos disponibles.


Assuntos
Esclerose Múltipla/terapia , Complicações na Gravidez/terapia , Pesquisa Biomédica , Congressos como Assunto , Feminino , Humanos , Gravidez
8.
Semin Cardiothorac Vasc Anesth ; 24(1): 104-114, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31390944

RESUMO

The clinical, educational, and research facets of lung transplantation have advanced significantly since the first lung transplant in 1963. The formation of the International Society for Heart and Lung Transplantation (ISHLT) and subsequent Registry has forged a precedent of collaborative teamwork that has significantly affected current lung transplantation outcomes. The Society for the Advancement of Anesthesia (SATA) is dedicated to developing educational platforms for all facets of transplant anesthesia. Additionally, we believe that the anesthetic training for lung transplantation has not kept pace with other advances in the field. As such, SATA presents for consideration these educational milestones and competencies for anesthetic fellowship training in the field of lung transplantation. The proposed milestones were designed on the framework of 6 core competencies created by the Accreditation Council on Graduate Medical Education. The milestones were identified by combining the expert opinion of our Thoracic Transplant Committee, our experience as educators, and literature review. We offer this White Paper to the anesthesiology and transplant communities as a starting point for the discussion and evolution of perioperative anesthetic care in the field of lung transplantation.


Assuntos
Anestesia/métodos , Anestesiologia/educação , Bolsas de Estudo , Transplante de Pulmão/educação , Acreditação , Competência Clínica , Educação de Pós-Graduação em Medicina/métodos , Humanos , Transplante de Pulmão/métodos , Assistência Perioperatória/educação , Sociedades Médicas
9.
Rev Neurol ; 68(3): 132-133, 2019 Feb 01.
Artigo em Espanhol | MEDLINE | ID: mdl-30687923
10.
Semin Cardiothorac Vasc Anesth ; 23(1): 88-107, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30229690

RESUMO

Right ventricular (RV) function is an independent prognostic factor for short- and long-term outcomes in cardiac surgical patients. Patients with mitral valve (MV) disease are at increased risk of RV dysfunction before and after MV operations. Yet RV function is not part of criteria for decision making or risk stratification in this setting. The role of MV disease in the development of pulmonary hypertension (PHTN) and the ultimate impact of PHTN on RV function have been well described. Nonetheless, there are other mechanisms by which MV disease and MV surgery affect RV performance. Research suggests that PHTN may not be the most important determinant of RV dysfunction. Both RV dysfunction and PHTN have independent prognostic significance. This review explores the unique anatomic and functional features of the RV and the pathophysiologic and prognostic implications of RV dysfunction in patients with MV disease in the perioperative period.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/cirurgia , Disfunção Ventricular Direita/complicações , Humanos , Hipertensão Pulmonar/complicações , Valva Mitral/fisiopatologia , Valva Mitral/cirurgia
11.
Ann Thorac Surg ; 107(6): 1768-1774, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30582926

RESUMO

BACKGROUND: Right heart failure occurs in 9% to 44% of left ventricular assist device (LVAD) implants, of which less than 10% require right ventricular assist device (RVAD) support either concurrently with the LVAD or staged, as a delayed procedure. We have reported our outcomes based on whether the RVAD was placed concurrently or staged. METHODS: Clinical data were obtained from the Duke University Medical Center database. The study focused on all consecutive adult patients who received continuous flow LVAD with either concurrent or staged (within 7 days) extracorporeal, temporary RVAD, between October 2007 and October 2017. Adverse event profiles and ability to wean from RVAD were compared between these two groups. RESULTS: Overall, 43 patients required an extracorporeal RVAD; 67% (n = 29) were implanted concurrently and 33% (n = 14) were implanted as staged after the LVAD. In all, 67% of patients (n = 29) could be weaned to an isolated LVAD. The 30-day, inhospital, and total mortality rates for our cohort were 14%, 28%, and 51% respectively. The mortality rate in the study period for the staged implants was 71% versus 45% for the concurrent implants (p = 0.101). In addition, staged RVAD implantation carried a significantly higher rate of postoperative renal failure (64% versus 28%, p = 0.044). CONCLUSIONS: There was a low incidence of need for RVAD in our cohort. The majority could be weaned to an isolated LVAD. Morbidity and mortality rates of this mode of biventricular support remain high. Early institution of RVAD support was associated with reduced rates of post-LVAD renal failure rates.


Assuntos
Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Complicações Pós-Operatórias/cirurgia , Adulto , Idoso , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
12.
Radiologia (Engl Ed) ; 60(6): 496-503, 2018.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30266206

RESUMO

AIM: To describe the findings and behaviour of contrast-enhanced ultrasound in the study of upper tract urothelial tumours and to assess its usefulness for diagnosis. MATERIAL AND METHODS: We reviewed our hospital's database over a period of 45 months to identify patients diagnosed with upper tract urothelial carcinomas. We reviewed the findings on mode B-ultrasound, contrast-enhanced ultrasound (location and qualitative assessment of intensity and washout of enhancement), and made a comparison with other techniques (computed tomography or magnetic resonance), and with the surgical specimen. RESULTS: We found 42 patients with a diagnosis of upper tract urothelial carcinoma confirmed with surgery over the period reviewed. Twenty-eight (67%) patients underwent contrast-enhanced ultrasound. Baseline ultrasound showed hydronephrosis with or without ureteral dilatation with echogenic content occupying the renal calyx (6), pelvis (10) or ureter (12). After injection of contrast, enhancement was noticed in 100% of the lesions, with similar intensity to the cortex in 23, and less in 5. Twenty-four lesions showed early washout, before the cortex, between 40 and 55seconds after the injection. The diagnosis was correct in 27 cases. Localisation coincided with the histological specimen in 28 cases, and 3 patients had additional distal carcinoma foci. CONCLUSION: Contrast-enhanced ultrasound is a useful technique for diagnosing upper tract urothelial tumours that increases confidence in the diagnosis.


Assuntos
Carcinoma de Células de Transição/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Pelve Renal/diagnóstico por imagem , Neoplasias Ureterais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia/métodos
13.
Can J Anaesth ; 65(1): 46-59, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29098634

RESUMO

BACKGROUND: Preoperative and postoperative anemia have been identified individually as potential risk factors for postoperative complications after coronary artery bypass grafting (CABG) surgery. Their interrelationship with acute kidney injury (AKI) and long-term mortality, however, has not been clearly defined and was the purpose of this study. METHODS: We retrospectively evaluated 6,130 adult patients undergoing CABG surgery performed at a single large academic medical center. Preoperative and postoperative hemoglobin concentrations were used as continuous predictors of postoperative AKI and mortality. Additionally, sex-specific preoperative (< 13 g·dL-1 in men and < 12 g·dL-1 in women) and postoperative anemia (the median of the lowest in-hospital values) were used as categorical predictors. AKI was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guidelines, when serum creatinine rose ≥ 50% during the period between day of surgery and postoperative day ten, or when a 0.3 mg·dL-1 (26.5 µmol·L-1) increase was detected in a rolling 48-hr window from the day of surgery to the tenth postoperative day. The association of preoperative and postoperative hemoglobin levels and anemia patterns with postoperative AKI and mortality were assessed via univariable and multivariable Cox proportional hazard analyses with time-varying effects for postoperative serum hemoglobin concentrations. RESULTS: The median preoperative and median minimum postoperative serum hemoglobin concentrations were 13.1 g·dL-1 and 8.8 g·dL-1, respectively. The incidence of AKI was 58%. Overall, 1,880 (30.7%) patients died an average of 6.8 yr after surgery. After adjusting for differences in baseline and clinical characteristics, on any given day, patients with preoperative anemia (multivariable hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.13 to 1.33; P < 0.001) and those with a combination of preoperative and postoperative anemia (multivariable HR, 1.24; 95% CI, 1.09 to 1.40; P < 0.0008) were at an elevated risk for developing postoperative AKI and mortality (preoperative anemia: multivariable HR, 1.29; 95% CI, 1.15 to 1.44; P < 0.001; preoperative and postoperative anemia: multivariable HR, 1.50; 95% CI, 1.25 to 1.79; P < 0.001). CONCLUSIONS: Our findings suggest that preoperative anemia alone and preoperative anemia combined with postoperative anemia are associated with AKI and mortality after CABG surgery.


Assuntos
Injúria Renal Aguda/epidemiologia , Anemia/complicações , Ponte de Artéria Coronária/métodos , Complicações Pós-Operatórias/epidemiologia , Centros Médicos Acadêmicos , Idoso , Idoso de 80 Anos ou mais , Anemia/epidemiologia , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/mortalidade , Creatinina/sangue , Feminino , Hemoglobinas/metabolismo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Período Pré-Operatório , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco
14.
Best Pract Res Clin Anaesthesiol ; 31(2): 237-248, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29110796

RESUMO

Cardiac transplantation remains the gold standard in the treatment of advanced heart failure. With advances in immunosuppression, long-term outcomes continue to improve despite older and higher risk recipients. The median survival of the adult after heart transplantation is currently 10.7 years. While early graft failure and multiorgan system dysfunction are the most important causes of early mortality, malignancy, rejection, infection, and cardiac allograft vasculopathy contribute to late mortality. Chronic renal dysfunction is common after heart transplantation and occurs in up to 68% of patients by year 10, with 6.2% of patients requiring dialysis and 3.7% undergoing renal transplant. Functional outcomes after heart transplantation remain an area for improvement, with only 26% of patients working at 1-year post-transplantation, and are likely related to the high incidence of depression after cardiac transplantation. Areas of future research include understanding and managing primary graft dysfunction and reducing immunosuppression-related complications.


Assuntos
Gerenciamento Clínico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/cirurgia , Transplante de Coração/mortalidade , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/tendências , Humanos , Imunossupressores/uso terapêutico , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento
15.
Rom J Anaesth Intensive Care ; 24(1): 57-63, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28913500

RESUMO

Surgical stress causes biochemical and physiologic perturbations of every homeostatic axis. These alterations include volume/baroreceptor regulation, sympathetic activation, parasympathetic suppression, neuroendocrine activation, acute phase response protein synthesis and secretion, immune response modulation and long-term behavioral adaptation. The kidney is central to the stress response because of its main role in the maintenance of water, electrolyte balance and hence, intracellular and extracellular compartments, including the intravascular volume. Acute kidney injury after cardiac surgery occurs as a result of numerous factors including ischemia-reperfusion, inflammation, oxidative stress, neurohormonal activation, metabolic factors, and nephrotoxicity or pigment nephropathy. The neuroendocrine stress response has a central role in initiating renal injury during cardiac surgery through an increased release of arginine-vasopressin and activation of the sympathetic nervous system and the intrarenal and systemic renin-angiotensin-aldosterone system. The contribution of an exaggerated neuroendocrine stress response to cardiac surgery and cardiopulmonary bypass as key pathophysiologic mechanism for acute kidney injury after cardiac surgery represents an opportunity for scientific exploration.

16.
Phys Med ; 38: 93-97, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28610703

RESUMO

PURPOSE: To analyze the air density dependence of the response of the new SourceCheck 4pi ionization chamber, manufactured by PTW. METHODS: The air density dependence of three different SourceCheck 4pi chambers was studied by measuring 125I sources. Measurements were taken by varying the pressure from 746.6 to 986.6hPa in a pressure chamber. Three different HDR 1000 Plus ionization chambers were also analyzed under similar conditions. A linear and a potential-like function of the air density were fitted to experimental data and their achievement in describing them was analyzed. RESULTS: SourceCheck 4pi chamber response showed a residual dependence on the air density once the standard pressure and temperature factor was applied. The chamber response was overestimated when the air density was below that under normal atmospheric conditions. A similar dependence was found for the HDR 1000 Plus chambers analyzed. A linear function of the air density permitted a very good description of this residual dependence, better than with a potential function. No significant variability between the different specimens of the same chamber model studied was found. CONCLUSION: The effect of overestimation observed in the chamber responses once they are corrected for the standard pressure and temperature may represent a non-negligible ∼4% overestimation in high altitude cities as ours (700m AMSL). This overestimation behaves linearly with the air density in all cases analyzed.


Assuntos
Ar , Braquiterapia , Radiometria/instrumentação , Radioisótopos do Iodo/análise , Pressão , Temperatura
17.
Phys Med ; 32(12): 1551-1558, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27890566

RESUMO

BACKGROUND AND PURPOSE: The study objective was to report our four-and-a half years experience (March 1 2011-August 15 2015) of a program to manage interruptions in fractionated radiotherapy treatments. METHODS: A program was developed, based on a specific database, to manage treatment interruptions. Benefits of the program were analyzed in reference to previously published data. Analysis was also performed of two measures to reduce OTT prolongation and improve treatment outcomes: working on public holidays and conducting treatment unit maintenance on Saturdays. RESULTS: The study included 2352 patients. Patients with head and neck cancer obtained the greatest benefit from the program, with a mean increase in TCP of 3.5% and a benefit of at least 4% in 45.6% of them. In prostate cancer patients, the likelihood of biochemical failure was reduced by a mean of 2.0% and was reduced by at least 4% in 19.7% of them. Application of the two proposed measures would have improved the TCP by a mean of 5.4% in head and neck cancer patients. The impact of the compensations program and proposed measures is lesser in the remaining cancer types studied. CONCLUSIONS: Implementation of a compensation program has a significant impact on patients with head and neck or prostate cancer but OTT prolongation remains excessive in many treatments. The introduction of fractions on public holidays would assist in the meeting of recommendations for these patients.


Assuntos
Fracionamento da Dose de Radiação , Radioterapia/métodos , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Fatores de Tempo
19.
Sci Total Environ ; 527-528: 159-64, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25965034

RESUMO

Understanding the role of biomacromolecules and their interactions with pollutants is a key for elucidating the sorption mechanisms and making an accurate assessment of the environmental fate of pollutants. The knowledge of the sorption properties of the different constituents of these biomacromolecules may furnish a significant contribution to this purpose. Suberin is a very abundant biopolymer in higher plants. In this study, suberin monomers isolated from cork were analyzed by thermally-assisted methylation with tetramethylammonium hydroxide (TMAH) in a pyrolysis unit coupled to gas chromatography-mass spectrometry (GC/MS). The isolated monomer mixture was used to study the sorption of three pesticides (isoproturon, methomyl and oxamyl). The modes of pesticide-sorbent interactions were analyzed by means of two modeling calculations, the first one representing only the mixture of suberin monomers used in the sorption study, and the second one including glycerol to the mixture of suberin monomers, as a building block of the suberin molecule. The results indicated that the highest sorption capacity exhibited by the sorbent was for isoproturon (33%) being methomyl and oxamyl sorbed by the main suberin components to a lesser extent (3% and<1%, respectively). In addition to van der Waals interactions with the apolar region of sorbent and isoproturon, modeling calculations evidenced the formation of a hydrogen bond between the isoproturon NH group and a carboxylic oxygen atom of a suberin monomer. In the case of methomyl and oxamyl only weak van der Waals interactions stabilize the pesticide-sorbent adducts. The presence of glycerol in the model provoked significant changes in the interactions with isoproturon and methomyl.


Assuntos
Lipídeos/química , Modelos Químicos , Praguicidas/química , Cromatografia Gasosa-Espectrometria de Massas
20.
Radiologia ; 57(2): 101-12, 2015.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25554118

RESUMO

Bile duct tumors are benign or malignant lesions which may be associated to risk factors or potentially malignant lesions. They constitute an heterogenous entities group with a different biological behavior and prognosis according to location and growth pattern. We revise the role of the radiologist in order to detect, characterize and stage these tumors, specially the importance of their classification when deciding an appropriate management and treatment.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Humanos , Lesões Pré-Cancerosas/diagnóstico por imagem
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