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.

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.

BackgroundPulmonary dysfunction is a known complication after cardiac surgery using cardiopulmonary bypass, ranging from subclinical functional changes to prolonged postoperative ventilation, acute lung injury, and acute respiratory distress syndrome. Whether human pulmonary arterial function is compromised is unknown. The aim of the present study was to compare the structure and function of isolated and cannulated human pulmonary arteries obtained from lung biopsies after the chest was opened (pre–cardiopulmonary bypass) to those obtained at the end of cardiopulmonary bypass (post–cardiopulmonary bypass) from patients undergoing coronary artery bypass graft surgery.Methods and ResultsPre‐ and post–cardiopulmonary bypass lung biopsies were received from 12 patients undergoing elective surgery. Intralobular small arteries were dissected, cannulated, pressurized, and imaged using confocal microscopy. Functionally, the thromboxane mimetic U46619 produced concentration‐dependent vasoconstriction in 100% and 75% of pre‐ and post–cardiopulmonary bypass arteries, respectively. The endothelium‐dependent agonist bradykinin stimulated vasodilation in 45% and 33% of arteries pre‐ and post–cardiopulmonary bypass, respectively. Structurally, in most arteries smooth muscle cells aligned circumferentially; live cell viability revealed that although 100% of smooth muscle and 90% of endothelial cells from pre–cardiopulmonary bypass biopsies had intact membranes and were considered viable, only 60% and 58%, respectively, were viable from post–cardiopulmonary bypass biopsies.ConclusionsWe successfully investigated isolated pulmonary artery structure and function in fresh lung biopsies from patients undergoing heart surgery. Pulmonary artery contractile tone and endothelium‐dependent dilation were significantly reduced in post–cardiopulmonary bypass biopsies. The decreased functional responses were associated with reduced cell viability.Clinical Trial Registration URL: http://www.isrctn.com/ISRCTN34428459. Unique identifier: ISRCTN 34428459.

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.

Objective: Pulmonary dysfunction is a common complication in patients undergoing heart surgery. Current clinical practice does not include any specific strategy for lung protection. To compare the anti-inflammatory effects of low-frequency ventilation (LFV), as measured by nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) p65 pathway activation, for the entire cardiopulmonary bypass (CPB) vs both lungs left collapsed in patients undergoing coronary artery bypass grafting (CABG).Methods: Two groups parallel randomized controlled trial. The primary outcome was inflammation measured by NF-κB p65 activation in pre-and post-CPB lung biopsies.Secondary outcomes were additional inflammatory markers in both biopsy tissue and blood.Results: Thirty-seven patients were randomly allocated to LFV (18) and to both lungs left collapsed (19). The mean concentration of NF-κB p65 in the biopsies before chest closure (adjusted for pre-CPB concentration) was higher in the LFV group compared to both lungs left collapsed group but this was not significant (0.102, 95% confidence interval, −0.022 to 0.226, P = 0.104). There were no significant differences between groups in the other inflammatory markers measured in tissue and blood. Conclusions:In patients undergoing elective CABG, the use of LFV during CPB when compared to both lungs left collapsed does not seem to reduce inflammation in lung biopsies and blood.

Coronary artery bypass grafting (CABG) remains the gold standard treatment in patients with complex multivessel coronary artery disease (CAD). Reversed long saphenous vein is the most commonly used conduit despite the known early thrombotic failure and low long-term patency rate. Post-operative antiplatelet therapy is an established treatment to improve graft patency and also a secondary treatment of the underlying native CAD.Aspirin has traditionally been the first line therapy; however, aspirin resistance especially in the early period after CABG, has been reported over the years and as a result, the use of dual antiplatelet therapy (DAPT) has become more common. However, there is limited evidence about the effect of DAPT and duration of use after CABG on graft patency, clinical outcomes (such as bleeding and myocardial infarction), and survival. The optimal dose of aspirin when given in DAPT is unclear and the duration of DAPT in association with quality of life is unknown.Furthermore, a better understanding of the pathology of vein graft disease and how available drugs influence it, could lead to the development of customised therapy for cohorts of patients undergoing CABG with potential benefits to early and long term outcomes. Here we review the available evidence on the routine use of DAPT after CABG. Coronary artery bypass grafting (CABG)Ischaemic heart disease (IHD) is the main leading cause of death in the world, with 7.4 million deaths in 2012 [1,2]. Coronary artery bypass grafting (CABG) is the gold standard intervention in patients with complex multivessel disease [3]. In the UK, there are about 25,000 CABG operations performed annually [4] and the majority of these operations is carried out on patients over 70 years of age [5]. Demand for CABG is likely to increase considerably in the future as a result of rapidly ageing populations [6] and increased expectations of patients and surgeons to expand their indications for surgery.During the early years of coronary surgery, saphenous vein grafts (SVGs) were the only conduits used [7]. Over the years different arterial conduits were introduced with variable degree of success [8][9][10]. Contemporary data on international use of grafts are available from the SYNTAX trial that included 1541 patients who underwent CABG at 85 sites in 18 countries between 2005 and 2007 [11]. The SYNTAX trial confirmed that the long saphenous vein (LSV) graft, is the most used conduit for multivessel revascularisation, despite its known low early and late patency rates.The underlying mechanism behind vein graft disease is multifactorial and can include conduit trauma/graft thrombosis (within 1 month, early failure), activation of intimal hyperplasia associated with harvest and implantation into the arterial high-pressure system (1 to 12 months, intermediate failure), superimposed atherosclerosis (beyond 12 months, late failure) [12][13][14][15]. A prospective cohort study of 1,388 patients carried out between 1969 to 1994, in which patency was assessed using coronary...

Omic analysis of lungs ventilation during open heart surgery.

No abstract