Computational fluid dynamicaccuracy in mimicking changes in blood hemodynamics in patients with acute type IIIb aortic dissection treated with TEVAR

Background: We aimed to verify the accuracy of the Computational Fluid Dynamics (CFD) algorithm for blood flow reconstruction for type IIIb aortic dissection (TBAD) before and after thoracic endovascular aortic repair (TEVAR). Methods: We made 3D models of the aorta and its branches using pre- and post-operative CT data from five patients treated for TBAD. The CFD technique was used to quantify the displacement forces acting on the aortic wall in the areas of endograft, mass flow rate/velocity and wall shear stress (WSS). Calculated results were verified with ultrasonography (USG-Doppler) data. Results: CFD results indicated that the TEVAR procedure caused a 7-fold improvement in overall blood flow through the aorta (p = 0.0001), which is in line with USG-Doppler data. A comparison of CFD results and USG-Doppler data indicated no significant change in blood flow through the analysed arteries. CFD also showed a significant increase in flow rate for thoracic trunk and renal arteries, which was in accordance with USG-Doppler data (accuracy 90% and 99.9%). Moreover, we observed a significant decrease in WSS values within the whole aorta after TEVAR compared to pre-TEVAR (1.34 ± 0.20 Pa vs. 3.80 ± 0.59 Pa, respectively, p = 0.0001). This decrease was shown by a significant reduction in WSS and WSS contours in the thoracic aorta (from 3.10 ± 0.27 Pa to 1.34 ± 0.11Pa, p = 0.043) and renal arteries (from 4.40 ± 0.25 Pa to 1.50 ± 0.22 Pa p = 0.043). Conclusions: Post-operative remodelling of the aorta after TEVAR for TBAD improved hemodynamic patterns reflected by flow, velocity and WSS with an accuracy of 99%

Biological parameters of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) assayed with Bacillus thuringiensis berliner

A bactéria Bacillus thuringiensis (Bt) é um promissor agente de controle de Spodoptera frugiperda (J.E. Smith). Além do efeito letal sobre os hospedeiros, os entomopatógenos podem causar alterações fisiológicas que comprometem o desenvolvimento dos insetos, podendo chegar a ponto de prejudicar a alimentação e/ou reprodução. No presente estudo, quatro bioensaios em laboratório foram realizados para verificar os efeitos subletais de isolados de Bt sobre os parâmetros biológicos de lagartas de segundo ínstar de S. frugiperda. A atividade de 39 isolados foi avaliada pelo peso de lagartas e de pupas fêmeas, oviposição e fecundidade de ovos de insetos sobreviventes. Foram observados efeitos subletais sobre as lagartas nos seguintes isolados: ESALQ 1.1, ESALQ 1.4, ESALQ 1.6, ESALQ 3.7, ESALQ 4.2 e ESALQ 5.2 (peso de lagartas e pupas fêmeas); ESALQ 5.1 (peso de lagartas); ESALQ 1.2 e ESALQ 3.7 (fecundidade dos ovos); ESALQ 3.7 (oviposição e fecundidade dos ovos) e ESALQ 3.7 e ESALQ 5.2 (oviposição). Quando os parâmetros foram analisados juntos, foram observadas correlações significativas entre eles, exceto no segundo bioensaio (peso de pupas fêmeas ´ oviposição, peso de pupas fêmeas ´ fecundidade dos ovos e oviposição ´ fecundidade dos ovos). Alguns isolados de Bt afetaram os parâmetros biológicos, principalmente peso de larvas e pupas fêmeas e, em alguns casos esses efeitos passaram para estágios posteriores do ciclo do inseto, afetando a oviposição e a viabilidade dos ovos. Embora, esses efeitos sejam difíceis de avaliar, especialmente em campo, eles deveriam ser considerados quando a atividade de um entomopatógeno é avaliada.The bacterium Bacillus thuringiensis (Bt) is a promising control agent of Spodoptera frugiperda (J.E. Smith). Besides the lethal effect on hosts, the entomopathogen may cause physiological alterations that hinder insects' feeding intake and reproduction. Larval and female pupa weight, oviposition and egg fecundity were determined in second instar S. frugiperda larvae infected with 39 Bt isolates in four bioassays. Sublethal effects were observed in the follow isolates: ESALQ 1.1, ESALQ 1.4, ESALQ 1.6, ESALQ 3.7, ESALQ 4.2 and ESALQ 5.2 (larval and female pupae weight); ESALQ 5.1 (larval weight); ESALQ 1.2 and ESALQ 3.7 (egg fecundity); ESALQ 3.7 (oviposition and egg fecundity); ESALQ 3.7 and ESALQ 5.2 (oviposition). Significant correlations were observed when parameters were analyzed together, except in the second bioassay (female pupal weight ´ oviposition, female pupal weight ´ egg fecundity and oviposition ´ egg fecundity). Some Bt isolates affected the biological parameters of S. frugiperda, mainly larval and female pupae weight, and in some instances these effects were passed on to further life cycle stages affecting oviposition and egg fecundity. Although sublethal effects are difficult to evaluate, mainly under field conditions, they should be considered when the activity of an entomopathogen is measured

Rationale and design of the PeriOperative ISchemic Evaluation-3 (POISE-3) : a randomized controlled trial evaluating tranexamic acid and a strategy to minimize hypotension in noncardiac surgery

Background For patients undergoing noncardiac surgery, bleeding and hypotension are frequent and associated with increased mortality and cardiovascular complications. Tranexamic acid (TXA) is an antifibrinolytic agent with the potential to reduce surgical bleeding; however, there is uncertainty about its efficacy and safety in noncardiac surgery. Although usual perioperative care is commonly consistent with a hypertension-avoidance strategy (i.e., most patients continue their antihypertensive medications throughout the perioperative period and intraoperative mean arterial pressures of 60 mmHg are commonly accepted), a hypotension-avoidance strategy may improve perioperative outcomes. Methods The PeriOperative Ischemic Evaluation (POISE)-3 Trial is a large international randomized controlled trial designed to determine if TXA is superior to placebo for the composite outcome of life-threatening, major, and critical organ bleeding, and non-inferior to placebo for the occurrence of major arterial and venous thrombotic events, at 30 days after randomization. Using a partial factorial design, POISE-3 will additionally determine the effect of a hypotension-avoidance strategy versus a hypertension-avoidance strategy on the risk of major cardiovascular events, at 30 days after randomization. The target sample size is 10,000 participants. Patients ≥45 years of age undergoing noncardiac surgery, with or at risk of cardiovascular and bleeding complications, are randomized to receive a TXA 1 g intravenous bolus or matching placebo at the start and at the end of surgery. Patients, health care providers, data collectors, outcome adjudicators, and investigators are blinded to the treatment allocation. Patients on ≥ 1 chronic antihypertensive medication are also randomized to either of the two blood pressure management strategies, which differ in the management of patient antihypertensive medications on the morning of surgery and on the first 2 days after surgery, and in the target mean arterial pressure during surgery. Outcome adjudicators are blinded to the blood pressure treatment allocation. Patients are followed up at 30 days and 1 year after randomization. Discussion Bleeding and hypotension in noncardiac surgery are common and have a substantial impact on patient prognosis. The POISE-3 trial will evaluate two interventions to determine their impact on bleeding, cardiovascular complications, and mortality

Effect of a perioperative hypotension-avoidance strategy versus a hypertension-avoidance strategy on the risk of acute kidney injury : a clinical research protocol for a substudy of the POISE-3 randomized clinical trial

Background: Most patients who take antihypertensive medications continue taking them on the morning of surgery and during the perioperative period. However, growing evidence suggests this practice may contribute to perioperative hypotension and a higher risk of complications. This protocol describes an acute kidney injury substudy of the Perioperative Ischemic Evaluation-3 (POISE-3) trial, which is testing the effect of a perioperative hypotension-avoidance strategy versus a hypertension-avoidance strategy in patients undergoing noncardiac surgery. Objective: To conduct a substudy of POISE-3 to determine whether a perioperative hypotension-avoidance strategy reduces the risk of acute kidney injury compared with a hypertension-avoidance strategy. Design: Randomized clinical trial with 1:1 randomization to the intervention (a perioperative hypotension-avoidance strategy) or control (a hypertension-avoidance strategy). Intervention: If the presurgery systolic blood pressure (SBP) is <130 mmHg, all antihypertensive medications are withheld on the morning of surgery. If the SBP is ≥130 mmHg, some medications (but not angiotensin receptor blockers [ACEIs], angiotensin receptor blockers [ARBs], or renin inhibitors) may be continued in a stepwise manner. During surgery, the patients’ mean arterial pressure (MAP) is maintained at ≥80 mmHg. During the first 48 hours after surgery, some antihypertensive medications (but not ACEIs, ARBs, or renin inhibitors) may be restarted in a stepwise manner if the SBP is ≥130 mmHg. Control: Patients receive their usual antihypertensive medications before and after surgery. The patients’ MAP is maintained at ≥60 mmHg from anesthetic induction until the end of surgery. Setting: Recruitment from 108 centers in 22 countries from 2018 to 2021. Patients: Patients (~6800) aged ≥45 years having noncardiac surgery who have or are at risk of atherosclerotic disease and who routinely take antihypertensive medications. Measurements: The primary outcome of the substudy is postoperative acute kidney injury, defined as an increase in serum creatinine concentration of either ≥26.5 μmol/L (≥0.3 mg/dL) within 48 hours of randomization or ≥50% within 7 days of randomization. Methods: The primary analysis (intention-to-treat) will examine the relative risk and 95% confidence interval of acute kidney injury in the intervention versus control group. We will repeat the primary analysis using alternative definitions of acute kidney injury and examine effect modification by preexisting chronic kidney disease, defined as a prerandomization estimated glomerular filtration rate <60 mL/min/1.73 m2. Results: Substudy results will be analyzed in 2022. Limitations: It is not possible to mask patients or providers to the intervention; however, objective measures will be used to assess acute kidney injury. Conclusions: This substudy will provide generalizable estimates of the effect of a perioperative hypotension-avoidance strategy on the risk of acute kidney injury

Estimating the direct costs of ischemic heart disease : evidence from a teaching hospital in Brazil, a retrospective cohort study

Background: Coronary artery disease is the most prevalent cardiovascular disease. In the United States, 7% of adults over 20 years of age are estimated to have coronary artery disease. In Brazil, a prevalence of 5 to 8% has been estimated in adults over 40 years of age, with an increased number of hospitalizations associated with both stable and acute clinical manifestations; and health care costs have quadrupled in the last decade. To estimate the direct costs of managing ischemic heart disease patient care in a teaching hospital in Brazil from the perspective of the service payer, the Brazilian Unified Health System. Methods: This study was a retrospective cohort study for the identification and valuation of resources used at both the outpatient and in-hospital levels in a sample of 330 patients selected from the hospital's ischemic heart disease clinic. Data were collected from computerized hospital records and patients' hospital bills from January 2000 to October 2015. A bivariate analysis and binary logistic regression were performed with p < 0.05 considered statistically significant Results: The study population consisted of 330 patients with a mean age 61 ± 10 years and a follow-up period of 107 ± 2.6 months; of the patients, 55% were male, 89% had hypertension, 48% had diabetes, and 65% had acute myocardial infarction. The mean annual cost of outpatient management was US $1,521 per patient. The mean cost per hospitalization was US$1,976, and the expenses were higher in the first and last years of follow-up. Unstable angina, revascularization procedures, diabetes, hypertension and obesity were predictors of higher hospitalization costs (p <0.05). Conclusion: The cost estimates in this study indicate a high proportion of drug treatment costs in the treatment of ischemic heart disease. Treatment costs are higher in the first year and at the end of treatment, and some clinical factors are associated with greater hospital care costs. These results may serve as a basis for the evaluation of existing public policies and inputs for cost-effectiveness studies in coronary artery disease. Trial registration: CEP HCPA 11–0460. Ethics Committee of Hospital de Clínicas de Porto Alegre

Evaluation of acute coronary syndrome in emergency departments

Dor torácica é um motivo freqüente de procura aos serviços de emergências, sendo responsável por 5-7% do atendimento nestes setores. Muito interesse tem sido focado na identificação de síndrome coronariana aguda nestes pacientes, entre eles infarto agudo do miocárdio e angina instável. Além da história clínica, do exame físico e do eletrocardiograma, os marcadores séricos de lesão miocárdica têm um papel importante em estabelecer o diagnóstico etiológico da dor e também auxiliar no encaminhamento para unidades com monitorização intensiva. As troponinas e as mioglobinas têm sido estudadas como novos marcadores séricos de lesão miocárdica. As troponinas são marcadores novos, que trouxeram um novo paradigma à avaliação de risco em síndrome coronariana aguda. Os dados levantados apontam que as mesmas apresentam uma acurácia muito boa para detecção de infarto e, de forma mais importante, identificam pacientes com pior prognóstico a curto e médio prazo. Apesar das informações sólidas na área, não existe consenso da melhor estratégia a ser seguida para utilização destes marcadores Troponinas têm sido preconizadas para todos os casos com suspeita de síndrome coronariana aguda, sendo que esta alternativa permite identificar um maior número de casos de infarto agudo do miocárdio, de acordo com classificação contemporânea. Se, por um lado, o custo do exame é um ônus para o sistema, do ponto de vista do hospital, a remuneração pelo novo diagnóstico compensa, além de sugerir maior eficiência no manejo dos casos de alto risco. Por outro lado, pacientes de baixo risco, sem alterações isquêmicas no eletrocardiograma e com marcadores séricos normais, podem se beneficiar de teste ergométrico precocemente. Se negativo, o mesmo tem um elevado valor preditivo negativo para eventos cardíacos até 6 meses da visita à emergência. A longo prazo, todos estes casos buscam atendimento médico com freqüência e precisam ser revistos em nível ambulatorial para assegurar um atendimento adequado.Chest pain is a common symptom in emergency department patients. It is responsible for 5-7% of emergency visits. Intense efforts have been given to identify patients with acute coronary syndromes, such as acute myocardial infarction or unstable angina. Besides clinical history, physical examination and ECG data, serum markers of myocardial injury play an important role in establishing diagnosis and helping triage patients to intensive care units. Troponins and myoglobins have been studied as new serum markers of myocardial injury. Troponins are new markers that brought a new paradigm in the identification of patients with acute myocardial infarction. Data presented show that troponins have a very good accuracy to identify myocardial infarction, and patients with short- and medium-term worse prognosis. In spite of the available information, there is no consensus on which strategy should be implemented to guide serum markers utilization. Troponins have been suggested for all patients with suspicion of acute coronary syndrome. This alternative allows the identification of a higher number of cases of acute myocardial infarction, according to the contemporary classification. On the one hand, troponin has a more favorable cost-effectiveness ratio when used in high risk patients. On the other hand, low risk patients, without ECG changes and with normal serum markers, could benefit from early exercise test. If negative, exercise test has a high negative predictive value for cardiac events within 6 months from emergency presentation. Long-term studies have shown increased return to emergency department, such that these patients need close follow-up in outpatient clinics