Clinical review: Practical recommendations on the management of perioperative heart failure in cardiac surgery

Acute cardiovascular dysfunction occurs perioperatively in more than 20% of cardiosurgical patients, yet current acute heart failure (HF) classification is not applicable to this period. Indicators of major perioperative risk include unstable coronary syndromes, decompensated HF, significant arrhythmias and valvular disease. Clinical risk factors include history of heart disease, compensated HF, cerebrovascular disease, presence of diabetes mellitus, renal insufficiency and high-risk surgery. EuroSCORE reliably predicts perioperative cardiovascular alteration in patients aged less than 80 years. Preoperative B-type natriuretic peptide level is an additional risk stratification factor. Aggressively preserving heart function during cardiosurgery is a major goal. Volatile anaesthetics and levosimendan seem to be promising cardioprotective agents, but large trials are still needed to assess the best cardioprotective agent(s) and optimal protocol(s). The aim of monitoring is early detection and assessment of mechanisms of perioperative cardiovascular dysfunction. Ideally, volume status should be assessed by 'dynamic' measurement of haemodynamic parameters. Assess heart function first by echocardiography, then using a pulmonary artery catheter (especially in right heart dysfunction). If volaemia and heart function are in the normal range, cardiovascular dysfunction is very likely related to vascular dysfunction. In treating myocardial dysfunction, consider the following options, either alone or in combination: low-to-moderate doses of dobutamine and epinephrine, milrinone or levosimendan. In vasoplegia-induced hypotension, use norepinephrine to maintain adequate perfusion pressure. Exclude hypovolaemia in patients under vasopressors, through repeated volume assessments. Optimal perioperative use of inotropes/vasopressors in cardiosurgery remains controversial, and further large multinational studies are needed. Cardiosurgical perioperative classification of cardiac impairment should be based on time of occurrence (precardiotomy, failure to wean, postcardiotomy) and haemodynamic severity of the patient's condition (crash and burn, deteriorating fast, stable but inotrope dependent). In heart dysfunction with suspected coronary hypoperfusion, an intra-aortic balloon pump is highly recommended. A ventricular assist device should be considered before end organ dysfunction becomes evident. Extra-corporeal membrane oxygenation is an elegant solution as a bridge to recovery and/or decision making. This paper offers practical recommendations for management of perioperative HF in cardiosurgery based on European experts' opinion. It also emphasizes the need for large surveys and studies to assess the optimal way to manage perioperative HF in cardiac surgery

Coxsackievirus B infections are common in Cystic Fibrosis and experimental evidence supports protection by vaccination

Viral respiratory tract infections exacerbate airway disease and facilitate life-threatening bacterial colonization in cystic fibrosis (CF). Annual influenza vaccination is recommended and vaccines against other common respiratory viruses may further reduce pulmonary morbidity risk. Enteroviruses have been found in nasopharyngeal samples from CF patients experiencing pulmonary exacerbations. Using serology tests, we found that infections by a group of enteroviruses, Coxsackievirus Bs (CVBs), are prevalent in CF. We next showed that a CVB vaccine, currently undergoing clinical development, prevents infection and CVB-instigated lung damage in a murine model of CF. Finally, we demonstrate that individuals with CF have normal vaccine responses to a similar, commonly used enterovirus vaccine (inactivated poliovirus vaccine). Our study demonstrates that CVB infections are common in CF and provides experimental evidence indicating that CVB vaccines could be efficacious in the CF population. The role of CVB infections in contributing to pulmonary exacerbations in CF should be further studied.publishedVersionPeer reviewe

Bacterial colonisation and infection of the lower airways in cystic fibrosis : a microbiological and clinical study

Pulmonary deterioration has remained the major cause of mortality in cystic fibrosis (C17) patients despite the considerable improvement of their survival due to more efficient therapy and centralised care. The progression of the CF lung disease is correlated to inflection with a limited number of colonising bacterial species. An inflammatory reaction in the lung occurs early. The general aim of this thesis was to study the bacterial colonisation in the lower airways of CF patients, and the concomitant inflammatory reaction. Paper I is a retrospective study of the chronic bacterial colonisation with Stenotrophomonas maltophilia in 12 CF patients during 1983-1992. No background factors for chronic colonisation could be verified in our material. An epidemiologic outbreak was not seen. The patients were older at the time of first isolation of S. maltophilia compared to that of Pseudomonas aeruginosa. Chronic colonisation implied a deterioration of the lung function during follow-up. The lung function of the patients was significantly worse at first isolation of S. maltophilia compared to controls colonised with P. aeruginosa at similar ages. Chronic colonisation and repeated antibiotic treatments resulted in rapid development of antimicrobial resistance. Thus, S. maltophilia is a pathogenic bacterium in patients with CF and a marker of lung disease. Paper II evaluates multiplex PCR-based detection of P. aeruginosa, S. maltophilia and Burkholderia cepacia in 90 sputum specimens compared to culture. Our data indicate high sensitivity (93%) regarding the detection of P. aeruginosa and high specificity regarding all three genera examined. The greatest gains with this method could be made when used for the early detection of P. aeruginosa in sputum-producing CF patients. Paper III describes typing of 39 clinical isolates of B. cepacia, which is an important pathogen, often associated with deterioration of the CF lung status. It exhibits a considerable phenotypic polymorphism. Typing by arbitrarily primed (AP)-PCR. using ERIC primer was performed for epidemiologic subtyping. Genetic changes were detected by analysis of shifts in the band patterns that were individual. Partial species identification could effectively be obtained by sequencing the V3 region of the 16S RNA gene. Heterogeneity of the bases was revealed in the same region in 10 of 37 strains, indicating at least two different types of 16S rRNA in the same cell. Most of the 14 CF patients, to whom 33 of the isolates belonged, developed severe lung disease after colonisation with Burkholderia, irrespective of the typing results. Paper IV investigates TN17-oc and IL-8 levels of sputum in 10 CF patients during exacerbation and the baseline levels of IL-8 in 48 sputum-producing CF patients. High IL-8 and TNF-[alpha] values in sputum seemed to correlate with clinical symptoms of deterioration and could be valuable diagnostic parameters. Our data also indicated a correlation between current bacterial colonisation with either P. aeruginosa or S. aureus in the lower airways and IL-8 concentrations in sputum. IL-8 in the sputum of CF patients seems to be a useful marker of both current bacterial colonisation and the degree of lung damage. Paper V evaluates the effect of 14-day ibuprofen therapy with special regard to IL-8 levels in sputum of 19 CF patients in clinically stable condition. The study was performed double-blinded, placebo-controlled in a crossover manner. Ibuprofen therapy did not result in significantly decreased IL-8 concentrations in the sputum of these CF patients with relatively advanced pulmonary disease. Slightly lower levels during day 8-14 of ibuprofen therapy were seen. Prescribing ibuprofen for this group of CF patients may need individual evaluation and will probably not be a general alternative

In-situ investigation of the decomposition process in cold-rolled Nb53Ti47 alloy

The multi-layer composite development primarily aims to develop and test the components of the next generation of hadron colliders (e.g., Large Hadron Collider - LHC) consisting of superconducting raw materials. Multilayer sheet is very similar to the commonly used NbTi wire products, a 2D version of the commercial wire. These composites consist of layers such as NbTi superconductor, Nb diffusion barrier (between NbTi and Cu) and Cu stabilizer. In β-NbTi superconducting alloys, α-Ti precipitates are primary flux pinning centers that maintain stable superconductivity. A multi-step series of heat treatments and cold-forming processes can develop the flux pinning centers. Practically, this process means three heat treatments of constant period and temperature and drawing or rolling between the heat treatments.The study aimed to describe the behavior of the cold-rolled (ε = 3.35) Nb53Ti47w% alloys during isothermal heating at 673 K as a function of heating time. The processes during the aging were investigated by the in-situ XRD method in the heating chamber. The X-ray diffraction patterns were evaluated by Rietveld refinement. The thermally activated spinodal decomposition and precipitation processes were described based on the phases identified at the individual heat treatment steps and their lattice parameters. The in-situ study also revealed an increase in α-Ti precipitation with time and decomposition that co-occurs. This is the basic study that prepares the applicability of the alloy

Diagnostic significance of measurements of specific IgG antibodies to Pseudomonas aeruginosa by three different serological methods

The aim of the study was to evaluate three serological methods for their ability to identify CF patients in different infection status especially those at risk of developing chronic Pseudomonas aeruginosa (Pa) infection. Methods: Two ELISA methods: exotoxin A (ExoA) and CF-IgG-ELISA (CF-IgG) and Crossed Immunoelectrophoresis (CIE) were used for measurement of Pa-antibodies in sera from 791 Scandinavian CF patients. Results: 381 patients were cultured negative for Pa in the year before study start, 129 patients were intermittently colonized and 281 patients were chronically infected. The sensitivity of the investigated assays was 96%, 93% and 97%, specificity 89%, 89% and 83% for CIE, ExoA and CF-IgG respectively. The negative predictive value was for CIE 97%, for ExoA 95% and for CF-IgG 98% and positive predictive values 87%, 86% and 80%. Out of the 381 patients cultured negative for Pa, 11 changed status to chronically infected. Twenty-four out of the 129 patients intermittently colonized became chronically infected. The antibody levels in this latter group of patients were significantly higher already at the study start and increased significantly during the study period (p < 0.05). Elevated levels of specific anti-Pseudomonal antibodies showed to be the risk factor for developing chronic P. aeruginosa infection (OR 4.9 and OR 2.7, p < 0.05 for CF-IgG and ExoA). Conclusion: All three serological assays were equally informative. The very high sensitivity of the assays made it possible to characterize patients with different infection status. Elevated levels of specific anti-Pseudomonas antibodies showed to be the risk factor for developing chronic Pa infection. Due to the specificity of the tests, antibiotic treatment based on serology might be considered in selected cases. There is a window of opportunity for suppression and eradication of initial P aeruginosa infection making measurement of specific anti-Pseudomonas antibodies helpful. (c) 2008 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved

Differences in prevalence and treatment of Pseudomonas aeruginosa in cystic fibrosis centres in Denmark, Norway and Sweden

AbstractBackgroundChronic Pseudomonas aeruginosa (PA) infection causes increased morbidity and mortality in cystic fibrosis (CF). This study aimed to answer the following questions: Does the prevalence of chronic infection with PA differ between the CF centres in Scandinavia? Which differences exist concerning segregation and treatment of PA?Methods989 patients (86%) from all eight CF-centres in Scandinavia were included. Demographic and clinical data, including PA colonisation status based on cultures and serology, were recorded at inclusion. The patients were followed prospectively for 1 year, recording number of days with anti-PA antibiotic treatment.ResultsIn all pancreatic insufficient (PI) patients (n=890) the prevalence of chronic PA infection at each centre ranged from 25.8% to 48.9%, but were not significantly different. In PI patients <19 years the prevalence was 14.5% in Copenhagen compared to 30.9% in the Swedish centres pooled (p=0.001). In intermittently colonised PI patients <19 years the median number of days per year on anti-PA antibiotics was almost 6 times higher in Copenhagen (mean 86 (110), median 61 days) compared to the Swedish centres pooled (mean 27 (52), median 11 days) (p=0.037). The pulmonary function was similar.ConclusionsIt is possible to maintain a very low prevalence of chronic PA infection in CF patients <19 years. We speculate that this was most likely due to a very intensive treatment of intermittently colonised patients with inhaled anti-PA antibiotics over prolonged periods of time in some centres. Since lung function was similar in centres with less intensive use of inhaled antibiotics, studies comparing different treatment modalities and other parts of CF care are needed to define the best clinical practice, including how to use antibiotics in the most rational way