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A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether beatingheart on-pump coronary artery bypass grafting (BH-ONCAB) offered superior mortality and morbidity outcomes when compared with conventional on-pump coronary artery bypass grafting (C-ONCAB). Morbidity outcomes consisted of renal failure, stroke (transient or permanent), myocardial infarction, angina, congestive cardiac failure, reintervention and arrhythmias. Best evidence papers investigating BHONCAB versus C-ONCAB were considered. Where data were duplicated, the more credible evidence-based and recently published study was included. Two hundred and thirty-one papers were found using the reported search, of which 11 represented the best evidence to answer the clinical question. Two were prospective randomized controlled trials and the remaining 10 observational studies, of which one was propensity-matched. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Five of these studies demonstrated significantly improved mortality following BH-ONCAB; however, one study exhibited better survival after C-ONCAB. Notably, this study incorporated BH-ONCAB patients with significantly more haemodynamic instability, thus possibly explaining the worse mortality outcomes. In terms of morbidity, a slightly more mixed picture is drawn. Five studies report morbidity in favour of BH-ONCAB, whereas three studies include individual outcomes favouring C-ONCAB. The remaining studies showed equivalent mortality and morbidity data. In summary, the results presented here suggest that BH-ONCAB may improve survival following coronary artery bypass surgery. A key observation is that the greatest benefits of BH-ONCAB appear to be in studies including patients with considerably higher risk characteristics at the time of surgery (haemodialysis, end-stage coronary artery disease, emergency surgery, low ejection fraction). There are limitations of the current evidence presented. Only two studies were randomized controlled trials. There was variability in sample size, selection criteria and preoperative risk profiles between the studies. The studies span many years, and the outcomes may have been affected byevolving technologies and differing patient profiles between these periods.

Objective We compared the efficacy of noninvasive ventilation with bilevel positive airway pressure added to usual care versus usual care alone in patients undergoing coronary artery bypass grafting. Methods We performed a 2-group, parallel, randomized controlled trial. The primary outcome was time until fit for discharge. Secondary outcomes were partial pressure of carbon dioxide, forced expiratory volume in 1 second, atelectasis, adverse events, duration of intensive care stay, and actual postoperative stay. Results A total of 129 patients were randomly allocated to bilevel positive airway pressure (66) or usual care (63). Three patients allocated to bilevel positive airway pressure withdrew. The median duration of bilevel positive airway pressure was 16 hours (interquartile range, 11-19). The median duration of hospital stay until fit for discharge was 5 days for the bilevel positive airway pressure group (interquartile range, 4-6) and 6 days for the usual care group (interquartile range, 5-7; hazard ratio, 1.68; 95% confidence interval, 1.08-2.31; P = .019). There was no significant difference in duration of intensive care, actual postoperative stay, and mean percentage of predicted forced expiratory volume in 1 second on day 3. Mean partial pressure of carbon dioxide was significantly reduced 1 hour after bilevel positive airway pressure application, but there was no overall difference between the groups up to 24 hours. Basal atelectasis occurred in 15 patients (24%) in the usual care group and 2 patients (3%) in the bilevel positive airway pressure group. Overall, 30% of patients in the bilevel positive airway pressure group experienced an adverse event compared with 59% in the usual care group. Conclusions Among patients undergoing elective coronary artery bypass grafting, the use of bilevel positive airway pressure at extubation reduced the recovery time. Supported by trained staff, more than 75% of all patients allocated to bilevel positive airway pressure tolerated it for more than 10 hours.

Heart disease is currently the world9s leading cause of death. Many heart conditions can only be treated through surgery, during which cardio-pulmonary bypass (CPB) is often used. During CPB the heart is stopped and the blood supply diverted from the heart and lungs to allow the operation to proceed in a largely blood-free environment. CPB is still associated with severe systemic inflammation and tissue damage and post-operative lung dysfunction of various degrees occurs in 30% of patients. In order to ascertain the mechanisms of lung injury we carried out non-biased transcriptomic (microarray) and proteomic analysis (Tandem Mass Tagging) on lung tissue from 36 patient both pre-surgery and post-CPB, immediately before reperfusion. 52 genes were significantly induced following CPB, including genes linked to inflammation: CCL2 9 (5x induction, p=5e-20), IL6 (4.6x, p=1.5e-14) and stress: EGR1 (4.6x p6.8e-17) and IER3 (4.1x, p=3.2e-17). Pathway analysis showed significant induction of the response to stress, immune system process and cellular process pathways. Proteomic analysis identified 95 proteins with greater than 50% change post-CPB, including inflammation (eosinophil peroxidase and Mucin-5B), metabolic changes (NADH dehydrogenase and TBC1 domain family), signalling molecules (calcium channels and lipid binding) and haemoglobin. Analysis of biological process identified changes including blood circulation, biogenesis and morphogenesis. Therefore, there is increased stress and inflammation in the lungs of patients undergoing CPB. Understanding the relationship between the cellular signalling pathways and the stress and inflammatory response in the lung may help us to reduce the damage to the lungs that occurs during CPB.

Pulmonary dysfunction is a common complication of cardiac surgery. The mechanisms involved in the development of pulmonary dysfunction are multifactorial and can be related to the activation of inflammatory and oxidative stress pathways. Clinical manifestation varies from mild atelectasis to severe respiratory failure. Managing pulmonary dysfunction postcardiac surgery is a multistep process that starts before surgery and continues during both the operative and postoperative phases. Different pulmonary protection strategies have evolved over the years; however, the wide acceptance and clinical application of such techniques remain hindered by the poor level of evidence or the sample size of the studies. A better understanding of available modalities and/or combinations can result in the development of customised strategies for the different cohorts of patients with the potential to hence maximise patients and institutes benefits.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether beating-heart on-pump coronary artery bypass grafting (BH-ONCAB) offered superior mortality and morbidity outcomes when compared with conventional on-pump coronary artery bypass grafting (C-ONCAB). Morbidity outcomes consisted of renal failure, stroke (transient or permanent), myocardial infarction, angina, congestive cardiac failure, reintervention and arrhythmias. Best evidence papers investigating BH-ONCAB versus C-ONCAB were considered. Where data were duplicated, the more credible evidence-based and recently published study was included. Two hundred and thirty-one papers were found using the reported search, of which 11 represented the best evidence to answer the clinical question. Two were prospective randomized controlled trials and the remaining 10 observational studies, of which one was propensity-matched. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Five of these studies demonstrated significantly improved mortality following BH-ONCAB; however, one study exhibited better survival after C-ONCAB. Notably, this study incorporated BH-ONCAB patients with significantly more haemodynamic instability, thus possibly explaining the worse mortality outcomes. In terms of morbidity, a slightly more mixed picture is drawn. Five studies report morbidity in favour of BH-ONCAB, whereas three studies include individual outcomes favouring C-ONCAB. The remaining studies showed equivalent mortality and morbidity data. In summary, the results presented here suggest that BH-ONCAB may improve survival following coronary artery bypass surgery. A key observation is that the greatest benefits of BH-ONCAB appear to be in studies including patients with considerably higher risk characteristics at the time of surgery (haemodialysis, end-stage coronary artery disease, emergency surgery, low ejection fraction). There are limitations of the current evidence presented. Only two studies were randomized controlled trials. There was variability in sample size, selection criteria and preoperative risk profiles between the studies. The studies span many years, and the outcomes may have been affected by evolving technologies and differing patient profiles between these periods.

Behçet's syndrome is a chronic multisystem inflammatory disease characterised classically by recurrent oral and genital ulcers with ocular lesions. It can affect blood vessels of all sizes, but involves veins more commonly than arterie. The presence of chylothorax in Behçet's syndrome is rare, with only a few cases cited in the literature. The most likely pathogenesis is SVC thrombosis with obstruction of the orifice of the thoracic duct resulting in leakage of chyle from the pleural lymphatics into the pleural space. The majority of the previously reported cases were managed medically without surgical intervention. We believe that this report describes the first use of surgery to ligate the thoracic duct and create a pericardial window in a Behçet's syndrome with chylothorax and chylopericardium.