Bloodless open heart surgery: simple and safe

OBJECTIVES: The use of blood or blood products is routine in cardiac surgery, but is associated with various complications. Aware of this, we have always tried to avoid the use of blood products whenever possible. In this study we sought to evaluate the results of this policy. METHODS: The records of 1505 adult patients who underwent coronary (732) or valve (773) surgery under cardiopulmonary bypass (CPB) in 2002 and 2003 were reviewed retrospectively. Of these, 1058 were male (70.3%) and the mean age was 62.1+/-11.4 years. Mean weight was 68.5+/-10.2 kg and body surface area was 1.7+/-0.2 m2, corresponding to a blood volume of 4119.9+/-593.6 ml. Preoperative hematocrit (Hct) was 40.6+/-4.2% and the prothrombin index was 87.0+/-17.4%. A bloodless prime of the bypass circuit was used for all patients with Hct > or =36%. The prime volume was reduced to the minimum possible. Plasma was used when coagulation was deficient. All blood remaining in the CPB circuit was reinfused at the end of the procedure, either in the operating room or in the ICU. Shed mediastinal blood was retransfused in the first 6 hours in the ICU. RESULTS: Operative mortality was 0.7% for coronary and 0.5% for valve patients. Blood or blood products were not used in 77.3% of the patients (88.7% of coronary and 66.5% of valve patients). Blood and/or plasma was initially added to the prime in 18.2% of cases and during CPB in 11%. Hct was 28.9+/-4.0% after initiation and 28.8+/-3.9% after discontinuation of CPB. The number of units (300 cc) of blood used was 0.25.57 per patient (1.09+/-0.73 per patient transfused). The number of units (300 cc) of plasma used was 0.24+/-0.72. Reoperation for bleeding was required in 2.4% of the patients. CONCLUSIONS: This blood-sparing policy is simple, effective and safe, resulting in low mortality and morbidity rates. More than three quarters of the patients did not require blood or blood products. Additional measures are possible to further decrease the use of blood products

Mechanical and wear behaviours of nano and microfilled polymeric composite: effect of filler fraction and size

The addition of ceramic reinforced material, SiC particles, to resin matrices, results in the improvement of the overall performance of the composite, allowing the application of these materials as tribo-materials in industries such as: automotive, aeronautical and medical. Particle-reinforced polymeric composites are widely used as biomaterials, for example as dental filler materials and bone cements. These reinforced composites have improved mechanical and tribological performance and have higher values of elastic modulus and hardness, and also reduce the shrinkage during the polymerisation compared with resin matrices. However, the effect of the filler level in mechanical and tribological behaviour is not quite understood. The aim of this work is to determine the influence of the particle volume fraction and particle size in the wear loss of the composites and their antagonists. Reciprocating wear tests were conducted using a glass sphere against resin polyester silica reinforced composite in a controlled medium, with an abrasive slurry or distilled water. For 6 μm average particle dimension, seven particles contents were studied ranging from 0% to 46% of filler volume fraction (FVF). Afterwards, filler volume fractions of 10% and 30% were selected; and, for these percentages, 7 and 4 average particle dimensions were tested and were evaluated regarding their wear behaviour, respectively. The reinforcement particle dimensions used ranged from 0.1 μm to 22 μm with the 10% filler fraction, and for 30% of filler content the range extended from 3 μm to 22 μm. The results allow us to conclude that in an abrasive slurry medium the composite abrasion resistance decreases with the increase of the particle volume fraction, in spite of the accompanying rise in hardness and elastic modulus. With constant FVF, and abrasive slurry, the composite wear resistance increases with increasing average particle dimension. In a distilled water medium and with several FVF values, the minimum wear was registered for a median particle content of 24%. In this medium and with constant FVF the highest wear resistance occurred for average reinforcement particles of 6 μm. The removal mechanisms involved in the wear process are discussed, taking into account the systematic SEM observations to evaluate the wear mechanisms

Técnicas alternativas no controle de podridões pós-colheita de pêssegos.

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How to break access control in a controlled manner

The Electronic Medical Record (EMR) integrates heterogeneous information within a Healthcare Institution stressing the need for security and access control. The Biostatistics and Medical Informatics Department from Porto Faculty of Medicine has recently implemented a Virtual EMR (VEMR) in order to integrate patient information and clinical reports within a university hospital. With more than 500 medical doctors using the system on a daily basis, an access control policy and model were implemented. However, the healthcare environment has unanticipated situations (i.e. emergency situations) where access to information is essential. Most traditional policies do not allow for overriding. A policy that allows for Break-The-Glass (BTG) was implemented in order to override access control whilst providing for non-repudiation mechanisms for its usage. The policy was easily integrated within the model confirming its modularity and the fact that user intervention in defining security procedures is crucial to its successful implementation and use

A decade of cardiac transplantation in Coimbra: the value of experience

INTRODUCTION AND OBJECTIVES: To analyze the experience gained in 10 years of the heart transplantation program of the University Hospital of Coimbra. METHODS: Between November 2003 and December 2013, 258 patients with a mean age of 53.0±12.7 years (3-72 years) and predominantly male (78%) were transplanted. Over a third of patients had ischemic (37.2%) and 36.4% idiopathic cardiomyopathy. The mean age of donors was 34.4±1.3 years and 195 were male (76%), with gender difference between donor and recipient in 32% of cases and ABO disparity (non-identical groups but compatible) in 18%. Harvest was distant in 59% of cases. In all cases total heart transplantation with bicaval anastomoses, modified at this center, was used. Mean ischemia time was 89.7±35.4 minutes. All patients received induction therapy. RESULTS: Early mortality was 4.7% (12 patients) from graft failure and stroke in five patients each, and hyperacute rejection in two. Thirteen patients (5%) required prolonged ventilation, 25 (11.8%) required inotropic support for more than 48 hours, and seven required pacemaker implantation. Mean hospital stay was 15.8±15.3 days (median 12 days). Ninety percent of patients were maintained on triple immunosuppressive therapy including cyclosporine, the remainder receiving tacrolimus. In 23 patients it was necessary to change the immunosuppression protocol due to renal and/or neoplastic complications and humoral rejection. All but two patients have been followed in the Surgical Center. Fifty patients (19.4%) subsequently died from infection (18), cancer (10), vascular (eight), neuropsychiatric (four), cardiac (two) or other causes (eight). Forty-six patients (17.8%) had episodes of cellular rejection (>2 R on the ISHLT classification), eight had humoral rejection (3.1%), and 22 have evidence of graft vascular disease (8.5%). Actuarial survival at 1, 5, and 8 years was 87±2%, 78±3% and 69±4%, respectively. CONCLUSION: This 10-year series yielded results equivalent or superior to those of centers with wider and longer experience, and have progressively improved following the introduction of changes prompted by experience. This program has made it possible to raise and maintain the rate of heart transplantation to values above the European average

Proteasome-mediated reduction in proapoptotic molecule Bim renders CD4⁺CD28null T cells resistant to apoptosis in acute coronary syndrome.

BACKGROUND: The number of CD4(+)CD28(null) (CD28(null)) T cells, a unique subset of T lymphocytes with proinflammatory and cell-lytic phenotype, increases markedly in patients with acute coronary syndrome (ACS). ACS patients harboring high numbers of CD28(null) T cells have increased risk of recurrent severe acute coronary events and unfavorable prognosis. The mechanisms that govern the increase in CD28(null) T cells in ACS remain elusive. We investigated whether apoptosis pathways regulating T-cell homeostasis are perturbed in CD28(null) T cells in ACS. METHODS AND RESULTS: We found that CD28(null) T cells in ACS were resistant to apoptosis induction via Fas-ligation or ceramide. This was attributable to a dramatic reduction in proapoptotic molecules Bim, Bax, and Fas in CD28(null) T cells, whereas antiapoptotic molecules Bcl-2 and Bcl-xL were similar in CD28(null) and CD28(+) T cells. We also show that Bim is phosphorylated in CD28(null) T cells and degraded by the proteasome. Moreover, we demonstrate for the first time that proteasomal inhibition restores the apoptosis sensitivity of CD28(null) T cells in ACS. CONCLUSIONS: We show that CD28(null) T cells in ACS harbor marked defects in molecules that regulate T-cell apoptosis, which tips the balance in favor of antiapoptotic signals and endows these cells with resistance to apoptosis. We demonstrate that the inhibition of proteasomal activity allows CD28(null) T cells to regain sensitivity to apoptosis. A better understanding of the molecular switches that control the apoptosis sensitivity of CD28(null) T cells may reveal novel strategies for targeted elimination of these T cells in ACS patients

PHENYTOIN – BOUNDARIES OF THE TREATMENT

Introdução: As crises convulsivas são manifestações clínicas frequentes no período neonatal. Continua pouco claro qual a melhor abordagem terapêutica, nao existindo ainda consenso entre os diversos protocolos. A terapêutica antiepiletica usada tradicionalmente e, muitas vezes, pouco eficaz e pode originar efeitos secundários importantes. Caso Clínico: Apresenta-se o caso clínico de um recém-nascido que iniciou convulsões no primeiro dia de vida. Por persistência das crises após terapêutica com fenobarbital, foi iniciada fenitoina, tendo desenvolvido um quadro de encefalopatia devida a intoxicação por este fármaco, apesar do seu uso em doses habituais. Dado que a investigacao complementar foi normal, concluiu-se que esta se deveu provavelmente a susceptibilidade individual. Conclusão: Atendendo aos potenciais efeitos secundários da fenitoina, mais frequentes e graves em recém-nascidos, este fármaco tende a ser menos usado como segunda linha no tratamento das convulsões neste grupo etário, considerando-se atualmente as benzodiazepinas e a lidocaina alternativas mais eficazes e seguras.Introduction: Seizures are rather common in the neonatal period. It still remains unclear what is the best therapeutic approach, and there is no consensus protocol. Currently used antiepileptic drugs are sometimes ineffective and may cause significant adverse effects. Case report: We present the case of a newborn with seizures during the first day of life. After unsuccessful treatment with phenobarbital, phenytoin was added. He developed a picture of encephalopathy due to intoxication with this drug, despite the use of standard dosages. Given unchanged further investigations, individual’s susceptibility was considered to be the cause. Conclusion: Because of potential side effects, more frequent and severe in newborns, phenytoin tends to be less used in the treatment of neonatal seizures. Benzodiazepines and lidocaine seems to be safer and more effective options

Limiting performance analisys of a head protection helmet using multicriteria control optimization

In this paper the limiting performance analysis of a head protection helmet is performed. A discrete model of the human head is used. A multicriteria optimum control problem is formulated in order to minimize the risk of injuries in case of impact. Several injury criteria are minimized and are required to remain below a safety threshold value. The optimal control force acting on the head is found. The optimal control force is determined by nonlinear programming. The equations of motion are integrated at-once, as it is typical for static response, instead of the traditional step-by-step integration.info:eu-repo/semantics/publishedVersio

Chronic mild prenatal stress exacerbates the allergen-induced airway inflammation in rats.

The effects of chronic mild prenatal stress on leukocyte infiltration into the airways was investigated in rat offspring. The chronic prenatal stress consisted of transitory and variable changes in the rat's living conditions. Offspring at adult age were actively sensitized (day 0) and intratracheally challenged (day 14) with ovalbumin. Bronchoalveolar lavage was performed in the offspring at 48 h after intratracheal challenge with ovalbumin. A significant increase in total leukocyte infiltration was observed in the non-stressed offspring group and this was associated with a marked recruitment of eosinophils without a significant effect on the influx of neutrophils and mononuclear cells. In the prenatal stressed offspring, the counts of both total leukocyte and eosinophils, as well as mononuclear cells, was increased by 50% compared to the non-stressed offspring. We provide here the first experimental evidence that chronic mild unpredictable prenatal stress produces a marked increase in the allergen-induced airway inflammation in the rat offspring