Aortic centres should represent the standard of care for acute aortic syndrome

Background Existing evidence suggests that patients affected by acute aortic syndromes (AAS) may benefit from treatment at dedicated specialized aortic centres. The purpose of the present study was to perform a meta-analysis to evaluate the impact aortic service configuration has in clinical outcomes in AAS patients. Methods The design was a quantitative and qualitative review of observational studies. We searched PubMed/ MEDLINE, EMBASE, and Cochrane Library from inception to the end of December 2017 to identify eligible articles. Areas of interest included hospital and surgeon volume activity, presence of a multidisciplinary thoracic aortic surgery program, and a dedicated on-call aortic team. Participants were patients undergoing repair for AAS, and odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were adopted for synthesizing hospital/30-day mortality. Results A total of 79,131 adult patients from a total of 30 studies were obtained. No randomized studies were identified. Pooled unadjusted ORs showed that patients treated in high-volume centres or by high-volume surgeons were associated with lower mortality rates (OR 0.51; 95% CI 0.46-0.56, and OR 0.41, 95% CI 0.25-0.66, respectively). Pooled adjusted estimates for both high-volume centres and surgeons confirmed these survival benefits (adjusted OR, 0.56; 95% CI 0.45-0.70, respectively). Patients treated in centres that introduced a specific multidisciplinary aortic program and a dedicated on-call aortic team also showed a significant reduction in mortality (OR 0.31; 95% CI 0.19-0.5, and OR 0.37; 95% CI 0.15-0.87, respectively). Conclusions We found that specialist aortic care improves outcomes and decreases mortality in patients affected by AAS

Validation of the European Multicenter Study on Coronary Artery Bypass Grafting (E-CABG) Bleeding Severity Definition

Background This study evaluated the prognostic significance of a novel bleeding severity classification in adult patients undergoing cardiac operations. Methods The European multicenter study on Coronary Artery Bypass Grafting (E-CABG) bleeding severity classification proposes 4 grades of postoperative bleeding: grade 0, no need of blood products with the exception of 1 unit of red blood cells (RBCs); grade 1, transfusion of platelets, plasma, or 2 to 4 units of RBCs, or both; grade 2, transfusion of 5 to 10 units of RBCs or reoperation for bleeding, or both; grade 3, transfusion of more than 10 units of RBCs. This classification was tested in a cohort of 7,491 patients undergoing CABG or valve operations, or combined procedures. Results The E-CABG bleeding severity grading method was an independent predictor of in-hospital death, stroke, acute kidney injury, renal replacement therapy, deep sternal wound infection, atrial fibrillation, intensive care unit stay of 5 days or more, and composite adverse events of death, stroke, renal replacement therapy, and intensive care unit stay of 5 days or more. The area under the receiver operating characteristic curve of the E-CABG bleeding severity grading method for predicting in-hospital death was 0.858 (95% confidence interval, 0.827 to 0.889). E-CABG bleeding severity grades 0 to 3 were associated with in-hospital mortality rates of 0.2%, 1.1%, 7.9%, and 29.0%, respectively (p <0.001), and with composite adverse events of 2.7%, 9.6%, 29.7%, and 75.8%, respectively (p <0.001). Conclusions The E-CABG bleeding severity classification seems to be a valuable tool in the assessment of the severity and prognostic effect of perioperative bleeding in cardiac operations

Validation of a New Classification Method of Postoperative Complications in Patients Undergoing Coronary Surgery

International audienceObjective The authors aimed to validate the European Multicenter Study on Coronary Artery Bypass Grafting (E-CABG) classification of postoperative complications in patients undergoing coronary artery bypass grafting (CABG). Design Retrospective, observational study. Setting University hospital. Participants A total of 2,764 patients with severe coronary artery disease. Complete baseline, operative, and postoperative data were available for patients who underwent isolated CABG. Interventions Isolated CABG. Measurements and Main Results The E-CABG complication classification was used to stratify the severity and prognostic impact of adverse postoperative events. Primary outcome endpoints were 30-day, 90-day, and long-term all-cause mortality. The secondary outcome endpoints was the length of intensive care unit stay. Both the E-CABG complication grades and additive score were predictive of 30-day (area under the receiver operating characteristics curve 0.866, 95% confidence interval [CI] 0.829-0.903; and 0.876; 95% CI 0.844-0.908, respectively) and 90-day (area under the receiver operating characteristics curve 0.850, 95% CI 0.812-0.887; and 0.863, 95% CI 0.829-0.897, respectively) all-cause mortality. The complication grades were independent predictors of increased mortality at actuarial (log-rank: p<0.0001) and adjusted analysis (p<0.0001; grade 1: hazard ratio [HR] 1.757, 95% CI 1.111-2.778; grade 2: HR 2.704, 95% CI 1.664-4.394; grade 3: HR 5.081, 95% CI 3.148-8.201). When patients who died within 30 days were excluded from the analysis, this grading method still was associated with late mortality (p<0.0001). The grading method (p<0.0001) and the additive score (rho, 0.514; p<0.0001) were predictive of the length of intensive care unit stay. Conclusions The E-CABG postoperative complication classification seems to be a promising tool for stratifying the severity and prognostic impact of postoperative complications in patients undergoing cardiac surger

Numerical simulation of the filling and curing stages in reaction injection moulding, using CFX

Mestrado em Engenharia MecânicaOs métodos habitualmente utilizados para a simulação de injecção em moldes envolvem um número considerável de simplificações, originando reduções significativas do esforço computacional mas, nalguns casos também limitações. Neste trabalho são efectuadas simulações de Reaction Injection Moulding (RIM) com o mínimo de simplificações, através da utilização do software de CFD multi-objectivos CFX, concebido para a simulação numérica de escoamentos e transferência de calor e massa. Verifica-se que o modelo homogéneo para escoamentos multifásicos do CFX, geralmente considerado o apropriado para a modelação de escoamentos de superfície livre em que as fases estão completamente estratificadas, é incapaz de modelar correctamente o processo de enchimento. Este problema é ultrapassado através da implementação do modelo não homogéneo juntamente com a condição de fronteira de escorregamento livre para o ar. A reacção de cura é implementada no código como uma equação de transporte para uma variável escalar adicional, com um termo fonte. São testados vários esquemas transitórios e advectivos, com vista ao reconhecimentos de quais os que produzem os resultados mais precisos. Finalmente, as equações de conservação de massa, quantidade de movimento, cura e energia são implementadas conjuntamente para simular os processos simultâneos de enchimento e cura presentes no processo RIM. Os resultados numéricos obtidos reproduzem com boa fidelidade outros resultados numéricos e experimentais disponíveis, sendo necessários no entanto tempos de computação consideravelmente longos para efectuar as simulações. ABSTRACT: Commonly used methods for injection moulding simulation involve considerable number of simplifications, leading to a significant reduction of the computational effort but, in some cases also to limitations. In this work, Reaction Injection Moulding (RIM) simulations are performed with minimum of simplifications, by using the general purpose CFD software package CFX, designed for numerical simulation of fluid flow and heat and mass transfer. The CFX’s homogeneous multiphase flow model, which is generally considered to be the appropriate choice for modelling free surface flows where the phases are completely stratified and the interface is well defined, is shown to be unable to model the filling process correctly. This problem is overcome through the implementation of the inhomogeneous model in combination with the free-slip boundary condition for the air phase. The cure reaction is implemented in the code as a transport equation for an additional scalar variable, with a source term. Various transient and advection schemes are tested to determine which ones produce the most accurate results. Finally, the mass conservation, momentum, cure and energy equations are implemented all together to simulate the simultaneous filling and curing processes present in the RIM process. The obtained numerical results show a good global accuracy when compared with other available numerical and experimental results, though considerably long computation times are required to perform the simulations

Bleeding in Patients Treated With Ticagrelor or Clopidogrel Before Coronary Artery Bypass Grafting

BackgroundWe evaluated perioperative bleeding after coronary artery bypass grafting (CABG) in patients preoperatively treated with ticagrelor or clopidogrel, stratified by discontinuation of these P2Y12 inhibitors.MethodsAll patients from the prospective, European Multicenter Registry on Coronary Artery Bypass Grafting (E-CABG) treated with ticagrelor or clopidogrel undergoing isolated primary CABG were eligible. The primary outcome measure was severe or massive bleeding defined according to the Universal Definition of Perioperative Bleeding, stratified by P2Y12 inhibitor discontinuation. Secondary outcome measures included four additional definitions of major bleeding. Propensity score matching was performed to adjust for differences in preoperative and perioperative covariates.ResultsOf 2,311 patients who were included, 1,293 (55.9%) received clopidogrel and 1,018 (44.1%) ticagrelor preoperatively. Mean time between discontinuation and the operation was 4.5 ± 3.2 days for clopidogrel and 4.9 ± 3.0 days for ticagrelor. In the propensity score–matched cohort, ticagrelor-treated patients had a higher incidence of major bleeding according to Universal Definition of Perioperative Bleeding when ticagrelor was discontinued 0 to 2 days compared with 3 days before the operation (16.0% vs 2.7%, p = 0.003). Clopidogrel-treated patients had a higher incidence of major bleeding according to the Universal Definition of Perioperative Bleeding when clopidogrel was discontinued 0 to 3 days compared with 4 to 5 days before the operation (15.6% vs 8.3%, p = 0.031).ConclusionsIn patients receiving ticagrelor 2 days before CABG and in those receiving clopidogrel 3 days before CABG, there was an increased rate of severe bleeding. Postponing nonemergent CABG for at least 3 days after discontinuation of ticagrelor and 4 days after clopidogrel should be considered.</div

Comparative Analysis of Prothrombin Complex Concentrate and Fresh Frozen Plasma in Coronary Surgery

BackgroundRecent studies suggested that prothrombin complex concentrate (PCC) might be more effective than fresh frozen plasma (FFP) to reduce red blood cell (RBC) transfusion requirement after cardiac surgery.MethodsThis is a comparative analysis of 416 patients who received FFP postoperatively and 119 patients who received PCC with or without FFP after isolated coronary artery bypass grafting (CABG).ResultsMixed-effects regression analyses adjusted for multiple covariates and participating centres showed that PCC significantly decreased RBC transfusion (67.2% vs. 87.5%, adjusted OR 0.319, 95%CI 0.136–0.752) and platelet transfusion requirements (11.8% vs. 45.2%, adjusted OR 0.238, 95%CI 0.097–0.566) compared with FFP. The PCC cohort received a mean of 2.7 ± 3.7 (median, 2.0, IQR 4) units of RBC and the FFP cohort received a mean of 4.9 ± 6.3 (median, 3.0, IQR 4) units of RBC (adjusted coefficient, −1.926, 95%CI −3.357–0.494). The use of PCC increased the risk of KDIGO (Kidney Disease: Improving Global Outcomes) acute kidney injury (41.4% vs. 28.2%, adjusted OR 2.300, 1.203–4.400), but not of KDIGO acute kidney injury stage 3 (6.0% vs. 8.0%, OR 0.850, 95%CI 0.258–2.796) when compared with the FFP cohort.ConclusionsThese results suggest that the use of PCC compared with FFP may reduce the need of blood transfusion after CABG.</p

Gender differences in outcomes after aortic aneurysm surgery should foster further research to improve screening and prevention programmes

Background: Gender-related biases in outcomes after thoracic aortic surgery are an important factor to consider in the prevention of potential complications related to aortic diseases and in the analysis of surgical results. Methods: The aim of this study is to provide an up-to-date review of gender-related differences in the epidemiology, specific risk factors, outcome, and screening and prevention programmes in aortic aneurysms. Results: Female patients affected by aortic disease still have worse outcomes and higher early and late mortality than men. It is difficult to plan new specific strategies to improve outcomes in women undergoing major aortic surgery, given that the true explanations for their poorer outcomes are as yet not clearly identified. Some authors recommend further investigation of hormonal or molecular explanations for the sex differences in aortic disease. Others stress the need for quality improvement projects to quantify the preoperative risk in high-risk populations using non-invasive tests such as cardiopulmonary exercise testing. Conclusions: The treatment of patients classified as high risk could thus be optimised before surgery becomes necessary by means of numerous strategies, such as the administration of high-dose statin therapy, antiplatelet treatment, optimal control of hypertension, lifestyle improvement with smoking cessation, weight loss and careful control of diabetes. Future efforts are needed to understand better the gender differences in the diagnosis, management and outcome of aortic aneurysm disease, and for appropriate and modern management of female patients

Direct proximal right subclavian artery cannulation during surgery of the thoracic aorta

Objective: To evaluate outcomes of single sternum access for right subclavian artery cannulation without infraclavicular incision in surgery of the thoracic aorta.Methods: Between January 2015 and December 2019, 44 consecutive patients underwent surgery of the thoracic aorta with cannulation of the right subclavian artery, after sternotomy and before pericardiotomy, through a direct percutaneous cannula with a single access without additional infraclavicular skin incision. The indication for surgery was type A acute aortic dissection in 29 patients (65.9%), proximal aortic aneurysm in 11 (25%), and aneurysm of the aortic arch in 4 (9%). Operative procedures were replacement of the ascending aorta in 23 patients, Bentall procedure in 10, hemiarch replacement in 6, and total arch replacement in 5. The mean cardiopulmonary bypass (CPB) and cross-clamp times were 185 +/- 62 minutes and 138 +/- 41 minutes, respectively.Results: The in-hospital mortality rate was 6.8%. Permanent neurologic dysfunction occurred in 3 patients (6.8%) and temporary neurologic dysfunction occurred in 4 patients (9.0%). There were no vascular complications related to this technique. No lesions to the vagus and recurrent laryngeal nerves have been reported.Conclusions: In our experience, a single sternum access for right subclavian artery cannulation avoids the risk and complications of an infraclavicular incision required for axillary artery cannulation. This technique is safe and represent a valid option for CBP and antegrade cerebral perfusion during surgery of the thoracic aorta